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The Johns Hopkins School Of Medicine - One of the best experts on this subject based on the ideXlab platform.

  • Oculopalatal tremor and internuclear ophthalmoplegia due to hemorrhagic pontine cavernoma
    Spencer S. Eccles Health Sciences Library University of Utah, 2018
    Co-Authors: Tony Brune, Department Of Neurology, The Johns Hopkins School Of Medicine
    Abstract:

    This is a 60-year-old woman who experienced 2 episodes of vertigo, nausea and vomiting, which was felt to be related to recurrent hemorrhage of a pontine cavernoma that was adjacent to the fourth ventricle. The cavernoma was resected, and diplopia and left facial palsy were noted after the surgery. About 6 months later, balance worsened and oscillopsia was experienced for the first time. At the time that this video was taken, more than 12 months had passed since the surgery. Deficits included left lower motor neuron (LMN) facial palsy (damage to the left fascicle of CN7), left internuclear ophthalmoplegia (INO -damage to the left medial longitudinal fasciculus), in addition to vertical-torsional pendular nystagmus and palatal tremor, consistent with oculopalatal tremor. Review of a recently obtained MRI showed bilateral hyperintensity of the inferior olives (IO) on MRI T2/FLAIR sequences due to hypertropic olivary degeneration (HOD). In her case, HOD was related to injury of the descending Central Tegmental Tract (CTT) as it passed through the pons, thereby removing normal inhibition of the IO by the CTT (https://collections.lib.utah.edu/details?id=1278831)

  • Oculopalatal tremor and one-and-a-half syndrome due to pontine hemorrhage
    Spencer S. Eccles Health Sciences Library University of Utah, 2018
    Co-Authors: Tony Brune, Department Of Neurology, The Johns Hopkins School Of Medicine
    Abstract:

    This is a 65-year-old man who was put on a blood thinner, and shortly thereafter experienced a midline pontine hemorrhage, which was more dense on the left side. Immediately afterwards, right hemiparesis and hemi-anesthesia, left lower motor neuron (LMN) facial palsy and ophthalmoparesis were noted. Months later, he experienced oscillopsia as well. At the time that this video was taken, he was about 6 months from the pontine hemorrhage. There was mainly vertical pendular nystagmus noted in the left eye, and there were vertical and horizontal (convergent-divergent) components in the right eye, along with palatal tremor, which is known as oculopalatal tremor (OPT). Vertical movements were normal and horizontal motility exam demonstrated a left internuclear ophthalmoplegia (INO -damage to the left medial longitudinal fasciculus [MLF]) and left horizontal gaze palsy (damage to left 6th nucleus affecting fibers destined for left lateral rectus and interneurons destined for right medial rectus via right MLF), and a partial right 6th nerve palsy, related to injury of the right 6th fascicle. The combination of left INO and left horizontal gaze palsy is also referred to as a one-and-a-half syndrome. Disjunctive nystagmus is common in OPT, and given the proximity of the descending Central Tegmental Tract (CTT) to the fascicle/nucleus of CN6 and MLF, horizontal motility deficits may cause disjunctive horizontal components as in this patient who couldn't adduct or abduct OS (i.e., nystagmus was pure vertical OS). Typically, pendular nystagmus in OPT is vertical, torsional, or vertical-torsional, although there may be horizontal components as well, sometimes with a convergent-divergent pattern. Review of a recently obtained MRI showed hyperintensity of the left inferior olive (IO) on MRI T2/FLAIR sequences due to hypertropic olivary degeneration (HOD). In his case, HOD was related to injury of the descending Central Tegmental Tract (CTT) as it passed through the pons, thereby removing normal inhibition of the IO by the CTT (https://collections.lib.utah.edu/details?id=1278831)

  • Slow saccades due to unilateral paramedian pontine reticular formation (PPRF) injury with preserved movements using the vestibulo-ocular reflex
    Spencer S. Eccles Health Sciences Library University of Utah, 2018
    Co-Authors: Tony Brune, Department Of Neurology, The Johns Hopkins School Of Medicine
    Abstract:

    This is a 60-year-old man who presented for imbalance and oscillopsia 10 months after surgery and 8 months after radiation for Merkel cell carcinoma of the neck. He developed imbalance after surgery and diplopia and oscillopsia 6 months prior to our evaluation. MRI showed enhancement of both 6th nerves, as well as the left 9th, 10th, 11th and ascending portions of the 12th cranial nerve. There was a mild left lower motor neuron facial palsy as well. Exam demonstrated mild right adduction and bilateral abduction deficits, without clear evidence of a right partial 3rd nerve palsy otherwise. Convergence was relatively spared compared to adduction OD. Saccades to the left were very slow, seemingly out of proportion to his mild motility deficits. Pursuit appeared normal vertically and horizontally. There was a right hypertropia due to a skew deviation with a left head tilt, and ocular counterroll with top poles deviated toward the left ear (i.e., a leftward ocular tilt reaction). There was very mild vertical-torsionalpendular nystagmus OS>OD, seen best with the ophthalmoscope (unable to appreciate in this video because it was so subtle). ; To an optokinetic stimulus moved to the right, there were no leftward fast phases. With head impulse testing to the left, there was were abnormal catch-up saccades suggesting unilateral vestibular loss on the left. Given the fact that leftward saccades were so slow, with head impulses to the right, leftward movements were very normal appearing -if slow leftward saccades were due to nuclear(left 6th nucleus)/infranuclear motility deficits, leftward movements with the vestibulo-ocular reflex (VOR) should look just as slow. In this case, the VOR resulted in much faster movements, which strongly suggests a supranuclear mechanism (in addition to the fact that his right adduction deficit improved with convergence); therefore, it was felt that the left paramedian pontine reticular formation (PPRF) had been preferentially affected as well. Additionally, there was no impairment of smooth pursuit to the left. A left dorsal pontine localization was also supported by pendular nystagmus that had the appearance of oculopalatal tremor, which is commonly related to pathology in the vicinity of the descending Central Tegmental Tract in the pons (in his case without palatal tremor or inferior olivary hypertrophy on MRI -perhaps full-blown ‘oculopalatal tremor' was evolving), and a left lower motor neuron (LMN) facial palsy, which if ‘Central', would also support a left pontine localization. However, in his case, a left peripheral LMN facial palsy was entirely possible. The skew deviation (right hypertropia) could theoretically relate to damage just caudal to the decussation involving the utricule-ocular motor fibers at the left pontomedullary junction, although since his disease was so multi-focal and given otherwise unremarkable imaging of the cerebellum and brainstem, it was difficult to localize all of his deficits

  • Oculopalatal tremor with prominent nystagmus, bilateral horizontal gaze palsy, and bilateral facial palsies Figure 1
    Spencer S. Eccles Health Sciences Library University of Utah, 2017
    Co-Authors: Tony Brune, Department Of Neurology, The Johns Hopkins School Of Medicine
    Abstract:

    Figure 1, MRI T2 sequence demonstrating hyperintensities involving bilateral inferior olives of the medulla. This is a 50-year-old woman who experienced the acute onset of right sixth and seventh nerve palsies and left hemiparesis. Two cavernomas within the right pons (one in the region of the facial colliculus) were demonstrated by MRI. Five years after her initial presentation she developed recurrent right facial palsy and dysphagia. Imaging revealed acute pontine hemorrhage and she underwent surgical resection of the cavernoma. Post-operatively, she had facial diplegia and bilateral horizontal gaze palsies. Several months later, she experienced vertical oscillopsia. On examination, she had continuous large amplitude vertical pendular nystagmus and symmetric palatal myoclonus. She had bilateral horizontal gaze palsies with intact vertical movements. Convergence increased her ability to adduct OU slightly. Review of her MRI two months post-operatively revealed surgical changes to the floor of the fourth ventricle as well as marked hyperintensities of the bilateral inferior olivary nuclei. This patient presented with classic features of oculopalatal tremor (OPT), including vertical pendular nystagmus, palatal myoclonus, and MRI evidence of inferior (medullary) olivary hypertrophy. Given the proximity of the Central Tegmental Tract to the abducens nuclei and facial nerve fascicles, she also had horizontal gaze palsy and facial diplegia. OPT develops weeks to months following an injury to the Guillain-Mollaret triangle, which is an imaginary triangle connecting the inferior olive of the medulla to the contralateral dentate nucleus of the cerebellum, with fibers then travelling from the dentate to the contralateral red nucleus (fibers wrap around the red nucleus) of the midbrain, and these fibers descend the Central Tegmental Tract to synapse on the ipsilateral inferior olive. Increased (and synchronous) transmission via gap junctions between olivary neurons and maladaptive cerebellar changes have been implicated in generating OPT. Treatment options for her pendular nystagmus include gabapentin or memantine. [[See video case: https://collections.lib.utah.edu/details?id=1290929 ]

  • Pons: 6th and 7th nerve anatomy and the Central Tegmental Tract
    Spencer S. Eccles Health Sciences Library University of Utah, 2017
    Co-Authors: Daniel R. Gold, Departments Of Neurology, Otolaryngology Head Neck - & Surgery, Emergency Medicine, And Medicine, The Johns Hopkins School Of Medicine
    Abstract:

    From this cross-section of the pons, the proximity of the 6th nucleus to the 7th nerve fascicles is apparent. This is the basis of the so-called facial colliculus syndrome, where an ipsilesional horizontal gaze palsy from a nuclear 6th lesion (usually related to stroke or demyelination) can be seen with an ipsilesional lower motor neuron (i.e., upper and lower face) facial palsy.; ; Ex) A right-sided lesion would cause inability to 1) abduct OD or 2) adduct OS, in addition to a right facial palsy.; ; Or, if the nucleus of 6 is affected in addition to the ipsilateral medial longitudinal fasciculus (MLF), there is an ipsilesional horizontal gaze palsy + an ipsilateral internuclear ophthalmoplegia (INO), the so-called "one-and-a-half" syndrome.; ; Ex) A right-sided lesion would cause inability to 1) abduct OD or 2) adduct OS due to right 6th nucleus lesion, and inability to adduct OD (INO) due to right MLF lesion. Commonly, a lower neuron facial palsy will be seen with a one-and-a-half syndrome as well. ; ; Also, it's important to note that the Central Tegmental Tract (CTT) courses through the vicinity of cranial nerves 6 and 7, so months following a lesion (usually hemorrhagic stroke>ischemic stroke>>demyelination or other), vertical-torsional pendular nystagmus and palatal tremor (together known as oculopalatal tremor) will develop given disruption within Mollaret's triangle, where the cerebellum normally has an inhibitory influence over the inferior olives via the CTT - i.e., with CTT damage, there is less inhibition of the inferior olives, resulting in inferior olivary hypertrophy on MRI, which is demonstrated by T2/FLAIR hyperintensity of one or both medullary olives

Junichi Takanashi - One of the best experts on this subject based on the ideXlab platform.

  • Central Tegmental Tract Involvement in an Infant with 6-Pyruvoyltetrahydropterin Synthetase Deficiency
    2015
    Co-Authors: Junichi Takanashi, Masaki Kanazawa, Yoichi Kohno
    Abstract:

    SUMMARY: We report the case of an asymptomatic 2-month-old infant with 6-pyruvoyltetrahydrop-terin synthetase deficiency detected through a neonatal phenylketonuria screening program. MR imaging revealed symmetrical lesions in the Central Tegmental Tract with reduced diffusion, which resolved after treatment. A possible explanation for these lesions is intramyelinic edema resulting from brain insults in utero. Tetrahydrobiopterin (BH4) deficiency comprises a heterog-enous group of disorders caused bymutations of one of the genes encoding enzymes involved in the synthesis or regener-ation of BH4. 1 It presents mostly with hyperphenylalaninemia (HPA) and a deficiency of neurotransmitter precursors L-dopa and 5-hydroxytryptophan and may be detected through neonatal phenylketonuria (PKU) screening pro-grams. BH4 deficiency (1/1,000,000) is much rarer than PKU (1/10,000). 6-Pyruvoyltetrahydropterin synthetase (PTPS) deficiency is the most common enzyme defect of BH4 defi

  • lesions in the Central Tegmental Tract in autopsy cases of developmental brain disorders
    Brain & Development, 2011
    Co-Authors: Mutsuki Shioda, Junichi Takanashi, Masaharu Hayashi, Makiko Osawa
    Abstract:

    We retrospectively analyzed Central Tegmental Tract (CTT) lesions in 120 consecutive autopsy cases of developmental brain disorders to investigate the significance of symmetrical CTT lesions. Magnetic resonance imaging (MRI) findings of CTT lesions have been sporadically reported in various cases of child neurological diseases. In this study, symmetrical CTT lesions were observed in 25 (20.8%) among 120 cases of developmental brain disorders. These 25 cases were classified into three groups (groups I–III) in decreasing order of the severity of the lesion. Compared to five cases of group I in which CTT lesions were accompanied by diffuse Tegmental damage, 20 cases of groups II or III developed relatively selective CTT lesions in which the medial longitudinal fasciculus and/or medial or lateral lemniscus were preserved. The causes of brain disorders in all three groups seemed to be different, and lysosomal disorders and congenital brain anomalies were frequently seen in cases in groups II and III, respectively. The dentato-rubro-olivary system is known to be involved in palatal myoclonus, and five out of 13 cases in group II showed myoclonic epilepsy. Compared with 95 cases without the CTT lesion, the changes in the pontine reticular formation were more closely associated with the CTT lesion than those in the inferior olivary nucleus. In conclusion, in cases of developmental brain disorders, the neuropathology of the symmetrical CTT lesion should be investigated.

  • Central Tegmental Tract involvement in an infant with 6 pyruvoyltetrahydropterin synthetase deficiency
    American Journal of Neuroradiology, 2006
    Co-Authors: Junichi Takanashi, Masaki Kanazawa, Yoichi Kohno
    Abstract:

    We report the case of an asymptomatic 2-month-old infant with 6-pyruvoyltetrahydropterin synthetase deficiency detected through a neonatal phenylketonuria screening program. MR imaging revealed symmetrical lesions in the Central Tegmental Tract with reduced diffusion, which resolved after treatment. A possible explanation for these lesions is intramyelinic edema resulting from brain insults in utero.

Philip T. Hicks - One of the best experts on this subject based on the ideXlab platform.

  • A Comparative Neuroanatomical Study of the Red Nucleus of the Cat, Macaque and Human
    2013
    Co-Authors: Satoru Onodera, Philip T. Hicks
    Abstract:

    Background: The human red nucleus (Nr) is comparatively less well-studied than that of cats or monkeys. Given the functional importance of reticular and midbrain structures in control of movement and locomotion as well as from an evolutionary perspective, we investigated the nature and extent of any differences in Nr projections to the olivary complex in quadrupedal and bipedal species. Using neuroanatomical Tract-tracing techniques we developed a ‘‘neural sheet’’ hypothesis allowing us to propose how rubro-olivary relations differ among the three species. Methods and Findings: Wheat germ agglutinin-horseradish peroxidase staining supports findings that the cat’s nucleus accessories medialis of Bechtrew (NB) projects mainly to the lateral bend of the principal olive. We clarified boundaries among nucleus of Darkschewitsch (ND), NB and parvicellular red nucleus (pNr) of the cat’s neural sheet. The macaque’s NDmedial accessory olivary projection is rostro-caudally organized and the dorsomedial and ventrolateral parts of the macaque’s pNr may project to the principal olive’s rostral and caudal dorsal lamella; in cat it projects as well to pNr. Myelinand Nissl-stained sections show that a well-developed dorsomedial part of the human Nr consists of densely packed cells, deriving small myelinated fibers that continue into the medial Central Tegmental Tract. Conclusions: Based on these findings we suggest there are distinct bipedal-quadrupedal differences for Nr projections to the olivary complex. We propose the Nr of cats and monkeys comprise the ND, NB and pNr in a zonal sheet-like structure

  • Human parvicellular red nucleus.
    2013
    Co-Authors: Satoru Onodera, Philip T. Hicks
    Abstract:

    Photomicrographs showing the distribution of myelinated fibers around NB and its adjacent nuclei (A, C, E and G). B, D, F and H show the distribution of small myelinated fibers. The arrowheads indicate nucleoli of small neurons. CTT – Central Tegmental Tract, dmpNr – dorsomedial part of parvicellular red nucleus, FR – fasciculus retroflexus, mNr – magnocellular red nucleus, NB – nucleus accessorius medialis of Bechterew, ND – nucleus of Darkschewitsch, Nint – interstitial nucleus of Cajal, PBP – parabrachial pigmented nucleus, SNc – substantia nigra pars compacta, vlpNr – ventrolateral part of parvicellular red nucleus. Scale bar  = 200 µm.

  • Human red nucleus and its surrounding structures.
    2013
    Co-Authors: Satoru Onodera, Philip T. Hicks
    Abstract:

    Upper photomicrographs (A-H) showing distribution of myelinated fiber bundles stained by myelin stain in the human mesodiencephalic structure of successive serial sections. Section A is the most rostral. The human NB is the dorsomedial cell-rich area of the red nucleus. Scale bar = 500 µm in H (also applies to A–G). Lower scale drawing showing the distribution of Nissl-stained cells found in the human mesodiencephalic structure as indicated by dots in the drawings of 15 successive serial sections. Section 1 is the most rostral. Sections 13 and 14 show giant mNr cells as large dots indicated by arrowheads. The number in the left corner of each photomicrograph and drawing is the rostrocaudal distance (in micrometers) from the rostral tip of the red nucleus. (A) – (H) correspond to Figs. 11A–H. CTT–Central Tegmental Tract, dmpNr–dorsomedial part of parvicellular red nucleus, EW–Edinger-Westphal nucleus, FR–fasciculus retroflexus, MLF–medial longitudinal fasciculus, mNr–magnocellular red nucleus, MTT–medial Tegmental Tract, NB–nucleus accessorius medialis of Bechterew, ND–nucleus of Darkschewitsch, SCP–superior cerebellar peduncle, vlpNr–ventorlateral part of parvicellular red nucleus, III–oculomotor nucleus, IV–trochlear nucleus.

  • Human parvicellular red nucleus.
    2013
    Co-Authors: Satoru Onodera, Philip T. Hicks
    Abstract:

    Photomicrographs showing the distribution of Nissl-stained pNr cells in A(1), B(3), C(4), E(7), and F(10) which correspond to sections 1, 3, 4, 7 and 10 of Fig. 10 and the distribution of myelinated fiber bundles stained by myelin stain in D which corresponds to section Fig. 10B. The number in the left corner of each photomicrograph is the rostrocaudal distance (in micrometers) from the rostral tip of the red nucleus. CTT–Central Tegmental Tract, dmpNr–dorsomedial part of parvicellular red nucleus, EW–Edinger-Westphal nucleus, FR–fasciculus retroflexus, MLF–medial longitudinal fasciculus, MTT–medial Tegmental Tract, NB–nucleus accessorius medialis of Bechterew, ND–nucleus of Darkschewitsch, Nint–interstitial nucleus of Cajal, vlpNr–ventorlateral part of parvicellular red nucleus. Scale bar = 200 µm in F (also applies to A–E).

  • Neural sheet model of red nucleus.
    2013
    Co-Authors: Satoru Onodera, Philip T. Hicks
    Abstract:

    A. In the cat, the poorly-developed neural sheet curves. B. In the macaque, the moderately developed neural sheet curves. C. In the human, the extremely well-developed neural sheet is completely rolled. The human NB is defined as the dorsomedial part of the red nucleus and it projects to the vl of PO via the medial part of the CTT. A strong stream of these well-developed CTT fibers separates the NB from ND. The gray color indicates a “still uncertain” projection. CTT–Central Tegmental Tract, dmpNr–dorsomedial part of parvicellular red nucleus, lb–lateral bend, MAO–medial accessory olive, MTT–medial Tegmental Tract, NB–nucleus accessorius medialis of Bechterew, ND–nucleus of Darkschewitsch, PO–principal olive, vl–ventral lamella, vlpNr–ventorlateral part of parvicellular red nucleus.

Yoichi Kohno - One of the best experts on this subject based on the ideXlab platform.

  • Central Tegmental Tract Involvement in an Infant with 6-Pyruvoyltetrahydropterin Synthetase Deficiency
    2015
    Co-Authors: Junichi Takanashi, Masaki Kanazawa, Yoichi Kohno
    Abstract:

    SUMMARY: We report the case of an asymptomatic 2-month-old infant with 6-pyruvoyltetrahydrop-terin synthetase deficiency detected through a neonatal phenylketonuria screening program. MR imaging revealed symmetrical lesions in the Central Tegmental Tract with reduced diffusion, which resolved after treatment. A possible explanation for these lesions is intramyelinic edema resulting from brain insults in utero. Tetrahydrobiopterin (BH4) deficiency comprises a heterog-enous group of disorders caused bymutations of one of the genes encoding enzymes involved in the synthesis or regener-ation of BH4. 1 It presents mostly with hyperphenylalaninemia (HPA) and a deficiency of neurotransmitter precursors L-dopa and 5-hydroxytryptophan and may be detected through neonatal phenylketonuria (PKU) screening pro-grams. BH4 deficiency (1/1,000,000) is much rarer than PKU (1/10,000). 6-Pyruvoyltetrahydropterin synthetase (PTPS) deficiency is the most common enzyme defect of BH4 defi

  • Central Tegmental Tract involvement in an infant with 6 pyruvoyltetrahydropterin synthetase deficiency
    American Journal of Neuroradiology, 2006
    Co-Authors: Junichi Takanashi, Masaki Kanazawa, Yoichi Kohno
    Abstract:

    We report the case of an asymptomatic 2-month-old infant with 6-pyruvoyltetrahydropterin synthetase deficiency detected through a neonatal phenylketonuria screening program. MR imaging revealed symmetrical lesions in the Central Tegmental Tract with reduced diffusion, which resolved after treatment. A possible explanation for these lesions is intramyelinic edema resulting from brain insults in utero.

Massachusetts General Hospital - One of the best experts on this subject based on the ideXlab platform.

  • Sixth Nerve Palsy
    Spencer S. Eccles Health Sciences Library University of Utah, 1995
    Co-Authors: Shirley H. Wray, Professor Of Neurology Harvard Medical School, Unit For Neurovisual Disorders, Massachusetts General Hospital
    Abstract:

    Esotropia; Abduction Weakness; Sixth Nerve PalsyPowerPoint Presentation: Clivus Chordoma: http://library.med.utah.edu/NOVEL/Wray/PPT/Clivus_Chordoma.ppt Shirley H. Wray, M.D., Ph.D., FRCP Harvard Medical SchoolDifficulty focusingThis 46 year old patient had at age 6, a tendency for the left eye to wander out. Her face photograph at that age shows an exotropia and at age 7, a year later, the exotropia was not quite as prominent. It was assumed that the exotropia was due to a non-paralytic strabismus. Past History: At age 1 fracture of the skull Since childhood the left eye wandered out She was never told she had a strabismus and never wore prism glasses. In Sept 1994 at age 46, she experienced intermittent double vision, seeing the image split apart horizontally, and persisting for approximately 2 minutes. By blinking her eyes she was able to refocus a single image. In December 1994 she had transient "kaleidoscopic" vision, by which she meant horizontal and oblique diplopia when she woke up. She noted this looking at the television set, the window frame or her bedside clock. By mid-December she had persistent horizontal double vision in primary gaze worse on looking to the left and was no longer able to refocus a single image but saw only one image if she closed one eye. She was referred to the Neurovisual Clinic at the Massachusetts General Hospital and admitted. Symptomatic Inquiry: No headaches, vertigo, ptosis, or unsteadiness Family History: Positive for diabetes and hypertension No history of neurological disease. Neuro-ophthalmological examination: Visual acuity 20/20 OD, 20/30 reads J2 OS Visual fields, pupils and fundus examination normal. Ocular Motility OS: Esotropia Weakness of full abduction Cranial nerves 3 and 4 normal Convergence normal Alternating exophoria at distance Vertical gaze normal Lower cranial nerves normal Neurological examination: Normal Diagnosis: Left sixth nerve palsy superimposed on a childhood non-paralytic esotropia Brain CT showed: 1. A lytic destructive lesion in the clivus with bony particles within the lesion. 2. The mass extended from the sella to the foramen magnum with extension laterally to the petrous apices and carotid canals. 3. There was a suggestion of erosion of the petrous apex on the left. 4. Partial erosion of the posterior wall of the sella 5. The mass abutted the posterior part of the left and right cavernous sinus Brain MRI showed: 1. A clival mass with extension into Meckel's cave and cavernous sinus on the left and circumferential encasement of the proximal left cavernous internal carotid artery (ICA). 2. Partial encasement of the right proximal cavernous ICA. Diagnosis: Clivus Chordoma Differential Diagnosis: Chondrosarcoma Neurosurgery Consult: The important features that established the tumor as inoperable, were the imaging studies showing infiltration and destruction of bone along the midline of the clivus stretching from the pituitary down to the lower clivus in addition to extension of the tumor into the left cavernous sinus encasing the left ICA. The patient was advised that the tumor was inoperable and biopsy was recommended. A transsphenoidal biopsy was performed. Pathology: Chordoma Treatment: Proton beam radiation to the mass and skull base.This 46 year old patient with an inoperable clivus chordoma has in her childhood photographs At age 6 exotropia of the left eye (OS) At age 7 exotropia appears less prominent The assumption was an exotropia due to a non-paralytic strabismus. At age 46 she became symptomatic with horizontal diplopia on looking left and OS deviated in. She had: • Esotropia OS • Paresis of full abduction • Paresis of abduction with OS fixing alone confirmed a paralytic sixth nerve palsy • An alternating exophoria at distanceNo neuroimaging studies are available in this patient.The abducens nucleus of the sixth nerve lies in the floor of the fourth ventricle, at the level of the lower pons, and contains three groups of neurons: 1. Abducens motoneurons which innervate the ipsilateral lateral rectus muscle. 2. Abducens internuclear neurons, which project to the contralateral medial rectus subnucleus of the oculomotor nucleus via the medial longitudinal fasciculus 3. Neurons that project to the cerebellar flocculus The genu of the facial nerve curves over the dorsal and lateral surfaces of the nucleus, while the medial longitudinal fasciculus lies medial to each nucleus. The abducens nerve fascicle join its passage in the pons, lies adjacent to the motor nucleus and fascicle of the facial nerve, the motor nucleus of the trigeminal nerve, the spinal Tract of the trigeminal nerve, the superior olivary nucleus, the Central Tegmental Tract, and the corticospinal Tract. The sixth nerve emerges from the brainstem between the pons and medulla, lateral to the pyramidal prominence. It then runs upwards along the ventral surface of the pons, lateral to the basilar artery, and passes between the pons and the anterior inferior cerebellar artery to ascend through the subarachnoid space along the clivus. It then pierces the dura mata, crosses around and through the inferior petrosal sinus, and passes under the petroclinoid (Gruber's ligament) in Dorello's canal to enter the cavernous sinus. In the cavernous sinus, the nerve bends laterally around the intracavernous segment of the internal carotid artery (ICA) and runs medial and parallel to the ophthalmic division (V1) of the trigeminal nerve. The ocular sympathetic fibers leave the ICA and join briefly with the abducens nerve before joining the ophthalmic division (V1) of the trigeminal nerve. Unlike the oculomotor (third nerve) and trochlear (fourth nerve) nerves, the abducens nerve does not lie within the lateral wall of the sinus, but rather it runs within the body of the sinus. The sixth nerve enters the orbit through the superior orbital fissure, passes through the annulus of Zinn, and innervates the lateral rectus muscle. See Ref (8) and (12) for full discussion.Review ref (8)Proton beam therapy to the mass and skull base.1. Chen KS, Hung IJ, Lin KL. Isolated abducens nerve palsy: an unusual presentation of leukemia. J Child Neurol 2002;17:850-851. http://www.ncbi.nlm.nih.gov/pubmed/12585727 2. Currie JN, Lubin JH, Lessell S. Chronic isolated abducens paresis from tumors at the base of the brain. Arch Neurol 1983;40:226-229. http://www.ncbi.nlm.nih.gov/pubmed/6830471 3. Harada T, Ohashi T, Ohki K et al. Clival chordoma presenting as acute esotropia due to bilateral abducens palsy. Ophthalmologica 1997;21:109-111. http://www.ncbi.nlm.nih.gov/pubmed/9097318 4. Harbison JW, Lessell S, Selhorst JB. Neuro-ophthalmology of sphenoid sinus carcinoma. Brain 1984;108:855-870. http://www.ncbi.nlm.nih.gov/pubmed/6478180 5. Ikezaki K, Toda K, Abe M, Tabuchi K. Intracavernous epidermoid tumor presenting with abducens nerve paresis - case report. Neurologia Medico-Chirurgica 1992;32:360-364. http://www.ncbi.nlm.nih.gov/pubmed/1381064 6. Ilhan O, Sener EC, Ozyar E. Outcome of abducens nerve paralysis in patients with nasopharyngeal carcinoma. Eur J Ophthalmol 2002;12:55-59. http://www.ncbi.nlm.nih.gov/pubmed/11936446 7. Keane JR. Bilateral sixth nerve palsy. Analysis of 125 cases. Arch Neurol 1976;33:681-683. http://www.ncbi.nlm.nih.gov/pubmed/184766 8. Leigh RJ, Zee DS. Diagnosis of Peripheral Ocular Motor Palsies and Strabismus. Ch 9:385-474. In: The Neurology of Eye Movements, Fourth Edition. Oxford University Press, NY 2006. 9. Lopez R, David NJ, Gargano F, Post JD. Bilateral sixth nerve palsies in a patient with massive pituitary adenoma. Neurology 1981;31:1137-1138. http://www.ncbi.nlm.nih.gov/pubmed/7196535 10. Morioka T, Matsushima T, Yokoyama N. Muratami H, Fujii K, Fukui M. Isolated bilateral abducens nerve palsies caused by rupture of a vertebral artery aneurysm. J Clin Neuroopthalmol 1992;12:263-267. http://www.ncbi.nlm.nih.gov/pubmed/1287052 11. Volpe NJ, Liebach NJ, Munzenrider JE, Lessell S. Neuro-ophthalmological findings in chordoma and chondrosarcoma of the skull base. Am J Ophthalmol 1993;115:97-104. http://www.ncbi.nlm.nih.gov/pubmed/8420385 12. Wong AM. Nuclear and Infranuclear Ocular Motor Disorders Chp 12:191-242. In: Eye Movement Disorders. Oxford University Press, 2008.curriculum_fellow; VBchordoma; MTemspsixthabducen

  • Pendular Vertical Oscillations
    Spencer S. Eccles Health Sciences Library University of Utah, 1992
    Co-Authors: Shirley H. Wray, Professor Of Neurology Harvard Medical School, Unit For Neurovisual Disorders, Massachusetts General Hospital
    Abstract:

    Pendular Vertical Oscillations; Lid Nystagmus; Bilateral Sixth Nerve Palsy; Bilateral Horizontal Gaze PalsyPowerPoint Presentations: Palatal Tremor: http://library.med.utah.edu/NOVEL/Wray/PPT/Palatal_Tremor.ppt Shirley H. Wray, M.D., Ph.D., FRCP Harvard Medical School Pendular Vertical Oscillations: http://library.med.utah.edu/NOVEL/Wray/PPT/Pendular_Vertical_Oscillations.ppt Shirley H. Wray, M.D., Ph.D., FRCP, Harvard Medical SchoolDouble visionIn 1996 this 50 year old woman had the acute onset of tingling in the left arm and mild ataxia. In 1974 because of progressive symptoms and the onset of double vision attributed to a bilateral sixth nerve palsy, she consulted a neurologist at an outside hospital. She was given a diagnosis of Multiple Sclerosis. In 1990, she developed slurred speech and difficulty swallowing, due to a pseudobulbar palsy and a right facial weakness. Brain MRI showed a pontomedullary cavernous angioma with evidence of previous hemorrhage. In 1992, she was admitted to the Massachusetts General Hospital for surgical treatment. Neurological Examination: Alert and oriented x3 Speech dysarthric Pupils equal, normal reflexes. Complete bilateral 6th nerve palsy with esotropia Trigeminal sensation intact to light touch and pinprick Brisk corneal reflex OU Right lower motor neuron 7th nerve palsy Decreased hearing on the right Tongue protruded in the midline Palatal tremor (myoclonus) Motor System: 5/5 throughout without drift Reflexes 2+ upper extremity,1+ lower extremity with equivocal plantar responses Sensory Examination: Normal Co-ordination: Ataxia finger-to-nose, left > right Left dysdiadochokinesis Wide based ataxic gait On 7/20/92 Posterior Fossa Craniectomy and C1 arch removal. Microsurgical resection of a pontomedullary cavernous angioma with placement of a right occipital ventriculosotomy. The operative course was remarkable for several episodes of severe bradycardia. Post-operatively she had labile blood pressure and was slow to recover from the anesthesia On examination of her eye movements she was found to have pendular vertical oscillations (PVOs). A CT brain scan showed the cavernous bed had only a minimal rim of blood. The ventricles were small, the ventriculostomy was in good position and there was no hemorrhage or hydrocephalus. Hospital Course: In the Neurosurgical ICU she had a tracheostomy and gastrostomy. On 7/25/92 she was able to move her head, shoulders, right arm and both legs on command. The left arm was paretic. She became decerebrate to deep pain. Neuro-ophthalmic Consultation: Alert and followed one step commands Ocular Motility: Pendular vertical oscillations Bilateral 6th nerve palsy Bilateral horizontal gaze palsy Esotropia OD > OS Skew deviation with vertical misalignment left eye hypertropic Vertical gaze full on command Horizontal oculocephalic reflex absent Vertical oculocephalic reflex normal Bilateral lower motor neuron facial palsy Palatal tremor (myoclonus) Hospital Course: On 8/8/92 bilateral tarsorrhaphies were performed to protect the cornea. She had a stormy post-operative course in the Neurosurgical ICU. In September 1992 she was transferred to the Respiratory ICU to help wean her off the ventilator. In the RICU she remained neurologically stable but had great difficulty being weaned off the ventilator. On 9/10/92 Brain MRI showed: Resection of a portion of the pons, and a portion of the rostral medulla in the floor of the 4th ventricle, with post surgical filling of the space with cerebrospinal fluid. In addition, there was T2 hypointensity in the surgical bed with a blooming effect on the susceptibility sequence due to chronic blood products. On the flow sequence imaging, there was a punctate region of slightly increase signal in the upper pons which was thought to represent blood products or a small residual portion of the cavernos angioma with slow flow within it. The patient left the MGH to go to a skilled nursing facility.This patient was filmed in the intensive care unit shortly after surgical resection of a pontomedullary cavernous angioma. The striking signs are: • Pendular vertical oscillations • Bilateral 6th nerve palsy • Bilateral horizontal gaze palsy • Esotropia OD > OS • Skew deviation with vertical misalignment left eye hypertropic • Vertical gaze full on command • Horizontal oculocephalic reflex absent • Vertical oculocephalic reflex normal • Bilateral lower motor neuron facial palsy • Palatal tremor (myoclonus) PVO's are characterized by • Smooth, pendular movements occurring at a frequency of 1 to 3 Hz (typically 2 Hz). • PVOs are accentuated under closed lids as in this patient • PVOs are synchronized with movements of the palate • Patient had no synchronous movements of the face, tongue or pharynx. Review ID923-1 and 936-4 alongside this case.No neuroimaging studies are available in this patient. Brain MRI findings in two other patients with palatal tremor are illustrated: Case 1: Figure 1. Axial NECT scan shows a large pontine hemorrhage extending to the midbrain in a patient (ID936-4), who survived this massive hypertensive intracranial hemorrhage. Two years later he developed a palatal tremor. Case 2: Figure 2. Axial T2WI in a patient who developed palatal tremor 6 months after a midbrain bleed from a cavernous malformation show a small mixed signal intensity in the dorsal midbrain tegmentum. Figure 3. Axial T2WI (same case as Fig. 2) shows bilateral enlargement of the inferior olivary nucleus with striking hyperintensity characteristic of classic hypertrophic olivary degeneration. Courtesy Anne Osborn, M.D.According to Guillain and Mollaret the crucial location for the lesion(s) producing palatal tremor is one that involves the dentato-olivary pathway through the superior cerebellar peduncle. This pathway is an interconnecting circuit connecting three brainstem nuclei - the dentate, the red nucleus and the inferior olivary nucleus. The lesion can be located in one of four places: 1. The dentate nucleus 2. The dentate outflow through the superior cerebellar peduncle 3. At the level of the red nucleus where the pathway passes dorsally and inferior to the contralateral red nucleus or 4. In the descending Central Tegmental Tract to the contralateral inferior olivary nucleus. More recent studies have implicated interruption of a pathway from the deep cerebellar nuclei through the superior cerebellar peduncle, which then loops caudally through the Central Tegmental Tract to the inferior olive. When the syndrome is due to unilateral infarction of the dentate nucleus and superior cerebellar peduncle, hypertrophic changes in the inferior olivary nucleus appear on the contralateral side.Histologically, the olivary nucleus is enlarged, due to hypertrophy of neurons that contain increased acetylcholinesterase reaction product. Such changes begin within a month of the stroke and maximize in about six months, and are accompanied by astrocytosis, and synaptic and axonal remodeling. At the same time, the number of olivary neurons progressively declines, so that after six years, they are less than 10% of control brains. Also, both the myelin and the axons of efferent fibers from olivary neurons are severely degenerated in patients with persistent palatal tremor who survive several years. Despite the anatomic demonstration of atrophy, functional imaging studies suggest increased metabolism of the inferior olive.Pontomedullary cavernous angioma with hemorrhageSurgical resection and placement of a ventriculostomy1. Dubinsky RM, Hallett M, Di Chiro G, Fulham M, Schwankhaus J. Increased glucose metabolism in the medulla of patients with palatal myoclonus. Neurology. 1991 Apr;41(4):557-562. http://www.ncbi.nlm.nih.gov/pubmed/2011257 2. Gautier JC, Blackwood W. Enlargement of the inferior olivary nucleus in association with lesions of the Central Tegmental Tract or dentate nucleus. Brain 1961;84(3):342-361. http://www.ncbi.nlm.nih.gov/pubmed/13897315 3. Goyal M, Versnick E, Tuite P, Saint Cyr J, Kucharczyk W, Montanera W, Willinsky R, Mikulis D. Hypertrophic olivary degeneration: meta-analysis of the temporal evolution of MR findings. Am J Neuroradiol 2000; 21:1073-1077. http://www.ncbi.nlm.nih.gov/pubmed/10871017 4. Guillain G, Mollaret P. Deux cas myoclonies synchrones et rhythmées vélo-pharyngo-laryngo-oculodiaphragmatiques: Le problèm anatomique et physiolopathologique de ce syndrome. rev. Neurol (Paris) 1931;2:545-566. 5. Keane JR. Acute vertical ocular myoclonus. Neurology 1986;36:86-89. http://www.ncbi.nlm.nih.gov/pubmed/3941790 6. Leigh RJ, Hong S, Zee DS, Optican LM. Oculopalatal tremor: clinical and computational study of a disorder of the inferior olive. Soc Neurosci Abstr 2005; 933.8. 7. Leigh RJ, Zee DS. Diagnosis of Nystagmus and Saccadic Intrusions. Chp 10:475-558. In: The Neurology of Eye Movements, 4th Edition. Oxford University Press, New York 2006. 8. Lopez LI, Bronstein AM, Gresty MA, Du Boulay EP, Rudge P. Clinical and MRI correlates in 27 patients with acquired pendular nystagmus. Brain. 1996;119:465-472. http://www.ncbi.nlm.nih.gov/pubmed/8800942 9. Nishie M, Yoshida Y, Hirata Y, Matsunaga M. Generation of symptomatic palatal tremor is not correlated with inferior olivary hypertrophy. Brain. 2002;125:1348-1357. http://www.ncbi.nlm.nih.gov/pubmed/12023323curriculum_fellow; VBneurodispontinehemorrhage; VBcavernnoushemangioma

  • Palatal Tremor
    Spencer S. Eccles Health Sciences Library University of Utah, 1991
    Co-Authors: Shirley H. Wray, Professor Of Neurology Harvard Medical School, Unit For Neurovisual Disorders, Massachusetts General Hospital
    Abstract:

    Pendular Vertical Oscillations; Full Vertical GazePowerPoint presentations: http://library.med.utah.edu/NOVEL/Wray/PPT/Palatal Tremor: Palatal_Tremor.ppt Shirley H. Wray, M.D., Ph.D., FRCP, Harvard Medical School Pendular Vertical Oscillations: http://library.med.utah.edu/NOVEL/Wray/PPT/Pendular_Vertical_Oscillations.ppt Shirley H. Wray, M.D., Ph.D., FRCP, Harvard Medical SchoolConstant movement of the eyes.The patient is a 60 year old woman with insulin dependent diabetes mellitus. She was legally blind as a result of diabetic retinopathy and bilateral vitreous hemorrhage. In 1987, she was admitted to her local hospital with slurred speech and a right hemiparesis progressing over a period of three days. Investigations revealed: Hypertension Cerebrovascular disease with 30% stenosis of the left internal carotid artery A small infarct in the left substantia nigra extending inferiorly into the left cerebral peduncle. She made an excellent recovery from her stroke and was treated with coumadin for six months. Coumadin was stopped when she developed progressive diabetic retinopathy. She lost vision in her left eye from a vitreous hemorrhage and unsuccessful vitreous surgery. In the right eye, she had a successful cataract exTraction and vitrectomy for a small vitreous hemorrhage. This was followed, however, by a recurrent vitreous hemorrhage which reduced her vision to light perception only. In 1991, four years after her stroke, she became aware that her eyes were constantly moving. Her daughter commented on her eyes "oscillating" and when the patient touched her eyeball she could feel her eyes moving up and down. Symptomatic inquiry: Negative for vertigo, headache or difficulty in swallowing. Past History: Diabetic peripheral neuropathy Thyroid disease, on replacement synthyroid Neuro-ophthalmological examination: Visual acuity OD light perception, OS NLP Pupil OD oval and fixed OS distorted and fixed The eye movements showed: • Constant low amplitude pendular vertical oscillations (PVOs) with eyes open and closed • Lid nystagmus • Normal horizontal saccades • Normal vertical saccades • Poor convergence • No suppression of the PVOs on attempted convergence to look at her finger held at near. The presence of PVOs prompted an examination of the palate which showed: Palatal tremor (myoclonus) with rhythmic movement of the soft palate at 3 to 4 Hz synchronous with the ocular PVOs. Neurological examination: Speech normal Minimal drift of the right upper extremity with hyperreflexia. Flexor plantar responses Peripheral motor-sensory neuropathy, absent ankle jerks, Co-ordination intact. Normal gait Investigations: Brain MRI: 1. Small cavitary infarct in the left substantia nigra extending inferiorly in the left cerebral peduncle. 2. Ill-defined signal abnormalities involving the pons bilaterally and a small (1-2 mm) lacune in the posterior limb of the internal capsule/thalamus on the right. 3. Extensive bilateral periventricular white matter signal abnormalities, and T2 bright signal in the right external capsule. These findings were non-specific and probably related to microangiopathic leukoencephalopathy. Brainstem MRI: A gradient echo volume acquisition through the brainstem with T1 weighting was obtained and the data reformatted in the axial plane with 1 mm sections. This study showed asymmetry of the ventral medulla at the level of the olives. The left olivary nucleus appeared smaller than the right. No other abnormality of the brainstem was detected. Impression: Asymmetry of the medullary olivary complexes with probable degenerative hypertrophy of the right inferior olivary nucleus. Chest fluoroscopy, at the time of intermittent hiccups, ruled out diaphragmatic myoclonus. Diagnosis: Brainstem infarction in the left substantia nigra/left cerebral peduncle Palatal tremor Pendular vertical oscillationsThis patient with palatal tremor had striking pendular vertical oscillations (PVOs) in Central gaze. The eye movements show: • Constant low amplitude PVOs with eyes open and closed • Lid nystagmus • Normal horizontal saccades • Normal vertical saccades • Poor convergence • No suppression of the PVOs on attempted convergence to look at her finger held at near. The palatal tremor filmed in the same frame as her face and eyes can be seen to be synchronous with the PVOs. The term ‘tremor' is more accurate than "myoclonus", since the movements of affected muscles are to-and-fro, and are approximately synchronized, typically at a rate of about two cycles per second. PVOs are characterized by: • Smooth, pendular movements occurring at a frequency of 1 to 3 Hz (typically 2 Hz). • PVOs are accentuated under closed lids • PVOs are synchronized with movements of the palate, facial muscles, pharynx, tongue, larynx and diaphragm. Conclusions from the analysis of eye movement recordings 1. PVOs are smooth rather than saccadic and have the velocity characteristics of normal convergence and divergence eye movements. Despite the absence of other components of the near triad (miosis and accommodation), the disorder retains certain features characteristic of normal vergence movements. 2. The eye movements are disjunctive, and furthermore the peak velocities achieved for various amplitudes are typical of normal vergence movements. 3. The pathological alterations resulting in PVO implicate a separately functioning, physiologically normal vergence system within the brainstem. 4. The continuous nature of PVOs distinguishes them from the nystagmus that occurs with Parinaud's syndrome, which is episodic and provoked by voluntary saccadic eye movements, especially attempted upgaze. 5. In cerebral Whipple's disease the abnormal eye movements have been ascribed to oscillations of the vergence system; hence the term pendular vergence oscillations.MRI in two cases of palatal tremor are illustrated: Case 1: Figure 1. Axial NECT scan shows a large pontine hemorrhage extending to the midbrain in patient (ID936-4), who survived this massive hypertensive intracranial hemorrhage and 2 years later developed palatal tremor. Case 2: Figure 2. Axial T2WI in a patient who developed palatal tremor 6 months after a midbrain bleed from a cavernous malformation shows a small mixed signal intensity lesion in the dorsal midbrain tegmentum. Figure 3. Axial T2WI (same case as Fig. 2) shows enlarged olives with striking hyperintensity characteristic for classic hypertrophic olivary degeneration. Courtesy Anne Osborn, M.D.According to Guillain and Mollaret the crucial location for the lesion(s) producing palatal tremor is one that involves the dentato-olivary pathway through the superior cerebellar peduncle. This pathway is an interconnecting circuit connecting three brainstem nuclei - the dentate, the red nucleus and the inferior olivary nucleus. The lesion can be located in one of four places: 1. The dentate nucleus 2. The dentate outflow through the superior cerebellar peduncle 3. At the level of the red nucleus where the pathway passes dorsally and inferior to the contralateral red nucleus or 4. In the descending Central Tegmental Tract to the contralateral inferior olivary nucleus. More recent studies have implicated interruption of a pathway from the deep cerebellar nuclei through the superior cerebellar peduncle, which then loops caudally through the Central Tegmental Tract to the inferior olive. When the syndrome is due to unilateral infarction of the dentate nucleus and superior cerebellar peduncle, hypertrophic changes in the inferior olivary nucleus appear on the contralateral side, as in this patient with a cavitary infarct in the left brainstem and contralateral hypertrophy of the right inferior olivary nucleus.Histologically, the olivary nucleus is enlarged, due to hypertrophy of neurons that contain increased acetylcholinesterase reaction product. Such changes begin within a month of the stroke and maximize in about six months, and are accompanied by astrocytosis, and synaptic and axonal remodeling. At the same time, the number of olivary neurons progressively declines, so that after six years, they are less than 10% of control brains. Also, both the myelin and the axons of efferent fibers from olivary neurons are severely degenerated in patients with persistent palatal tremor who survive several years. Despite the anatomic demonstration of atrophy, functional imaging studies suggest increased metabolism of the inferior olive.Pontine infarctionOnly rarely does palatal tremor resolve spontaneously. Gabapentin, ceruletide, memantine, and anticholinergic agents may help some patients. Drugs that block connexin channels and there by reduce synchronized discharge of electronically coupled olivary neurons might provide a new therapeutic approach.1. Averbuch-Heller L, Tusa RJ, Fubry L, Rottach KG, Ganser GL, Heide W, Büttner U, Leigh RJ. A double-blind controlled study of gabapentin and baclofen as treatment for acquired nystagmus. Ann Neurol 1997;41:818-825. http://www.ncbi.nlm.nih.gov/pubmed/9189045 2. Barton JJ, Cox TA. Acquired pendular nystagmus in multiple sclerosis: clinical observations and the role of optic neuropathy. J Neurol Neurosurg Psychiatry. 1993 Mar;56(3):262-267. http://www.ncbi.nlm.nih.gov/pubmed/8459242 3. Dehaene I., Van Zandycke M, Appel B. Acquired pendular nystagmus. Neuro-ophthalmol 1987;7(5);297-300. 4. Deuschl G, Toro C, Valls-Solé J, Zeffiro T, Zee DS, Hallett M. Symptomatic and essential palatal tremor. 1. Clinical, physiological and MRI analysis. Brain. 1994 Aug;117 ( Pt 4):775-788. http://www.ncbi.nlm.nih.gov/pubmed/7922465 5. Dubinsky RM, Hallett M, Di Chiro G, Fulham M, Schwankhaus J. Increased glucose metabolism in the medulla of patients with palatal myoclonus. Neurology. 1991 Apr;41(4):557-562. http://www.ncbi.nlm.nih.gov/pubmed/2011257 6. Gautier JC, Blackwood W. Enlargement of the inferior olivary nucleus in association with lesions of the Central Tegmental Tract or dentate nucleus. Brain 1961;84(3):342-361. http://www.ncbi.nlm.nih.gov/pubmed/13897315 7. Goyal M, Versnick E, Tuite P, Saint Cyr J, Kucharczyk W, Montanera W, Willinsky R, Mikulis D. Hypertrophic olivary degeneration: meta-analysis of the temporal evolution of MR findings. Am J Neuroradiol 2000; 21:1073-1077. http://www.ncbi.nlm.nih.gov/pubmed/10871017 8. Guillain G, Mollaret P. Deux cas myoclonies synchrones et rhythmées vélo-pharyngo-laryngo-oculodiaphragmatiques: Le problèm anatomique et physiolopathologique de ce syndrome. rev. Neurol (Paris) 1931;2:545-566. 9. Katz B, Hoyt W, Townsend J. Ocular Bobbing and Unilateral Pontine Hemorrhage. Report of a Case. J Clin Neuro-ophthalmol 1982;2:193-195. http://www.ncbi.nlm.nih.gov/pubmed/6217223 10. Keane JR. Acute vertical ocular myoclonus. Neurology 1986;36:86-89. http://www.ncbi.nlm.nih.gov/pubmed/3941790 11. Koeppen AH. Olivary hypertrophy; histochemical demonstration of hydrolytic enzymes. Neurology 1980;30:471-480. http://www.ncbi.nlm.nih.gov/pubmed/6245389 12. Leigh RJ, Hong S, Zee DS, Optican LM. Oculopalatal tremor: clinical and computational study of a disorder of the inferior olive. Soc Neurosci Abstr 2005; 933.8. 13. Leigh RJ, Zee DS. Diagnosis of Nystagmus and Saccadic Intrusions. Chp 10:475-558. In: The Neurology of Eye Movements, 4th Edition. Oxford University Press, New York 2006. 14. Lopez LI, Bronstein AM, Gresty MA, Du Boulay EP, Rudge P. Clinical and MRI correlates in 27 patients with acquired pendular nystagmus. Brain. 1996 Apr;119 ( Pt 2):465-472. http://www.ncbi.nlm.nih.gov/pubmed/8800942 15. Nishie M, Yoshida Y, Hirata Y, Matsunaga M. Generation of symptomatic palatal tremor is not correlated with inferior olivary hypertrophy. Brain. 2002 Jun;125(Pt 6):1348-1357. http://www.ncbi.nlm.nih.gov/pubmed/12023323 16. Ruigrok TJ, deZeeuw CI, Vogel J. Hypertrophy of inferior olivary neurons : a degenerative regenerative or plasticity phenomenon. Eur J Morphol 1990 ;28 :224-239. http://www.ncbi.nlm.nih.gov/pubmed/2245132 17. Samuel M, Torun N, Tuite PJ, Sharpe JA, Lang AE. Progressive ataxia and palatal tremor (PAPT): clinical and MRI assessment with review of palatal tremors. Brain. 2004 Jun;127(Pt 6):1252-1268. Epub 2004 Apr 16. http://www.ncbi.nlm.nih.gov/pubmed/15090471 18. Yokota T, Hirashima F, Furukawa T, Tsukagoshi H, Yoshikawa H. MRI findings of inferior olives in palatal myoclonus J Neurol 1989;236:115-116. http://www.ncbi.nlm.nih.gov/pubmed/270905

  • Bilateral Sixth Nerve Palsy
    Spencer S. Eccles Health Sciences Library University of Utah, 2026
    Co-Authors: Shirley H. Wray, Professor Of Neurology Harvard Medical School, Unit For Neurovisual Disorders, Massachusetts General Hospital
    Abstract:

    Esotropia; Bilateral Abduction Weakness; Bilateral Sixth Nerve PalsyDouble visionThe patient is a 60 year old woman who consulted her ophthalmologist with a chief complaint of double vision looking to the left. He diagnosed of a left sixth nerve palsy. No investigations were done. Two years later she complained of diplopia looking to the right. A diagnosis of bilateral sixth nerve palsy was made. She was referred to the Neurovisual Clinic at the Massachusetts General Hospital and was admitted. Brain CT showed: A large clivus vascular tumor without bone destruction consistent with a meningioma. Neuro-ophthalmological Examination: Visual acuity 20/25 OU Visual fields, pupils and fundus examination normal. Ocular Motility: Esotropia OD > OS Bilateral abduction weakness Cranial nerves 3 and 4 normal Lower cranial nerves normal Neurological examination: Motor System: Normal Sensory System: Normal Coordination: No ataxia Diagnosis: Bilateral sixth nerve palsy Clivus meningioma Neurosurgical Consult: Advised conservative management without a biopsy. She was lost to follow-up.This patient with a clivus tumor, diagnosed as an inoperable meningioma, had bilateral sixth nerve palsies. • Esotropia OD > OS • Bilateral abduction weakness • Cranial nerves 3 and 4 normal • Lower cranial nerves normal Bilateral isolated sixth nerve palsies are generally "bad news" and when present should be considered due to a posterior fossa tumor until proved otherwise. The etiology of bilateral sixth nerve palsies include: • CNS lymphoma infiltrating the cavernous sinus(ID946-2) • Demyelination • Wernicke's encephalopathy (ID163-3) • Meningitis • Increased intracranial pressure • Other clivus tumors such as chordoma (ID26-1) • Leptomeningeal carcinomatosisNo imaging studies are available in this patientThe abducens nucleus of the sixth nerve lies in the floor of the fourth ventricle, at the level of the lower pons, and contains three groups of neurons: 1. Abducens motoneurons which innervate the ipsilateral lateral rectus muscle. 2. Abducens internuclear neurons, which project to the contralateral medial rectus subnucleus of the oculomotor nucleus via the medial longitudinal fasciculus 3. Neurons that project to the cerebellar flocculus The genu of the facial nerve curves over the dorsal and lateral surfaces of the nucleus, while the medial longitudinal fasciculus lies medial to each nucleus. The abducens nerve fascicle during its passage in the pons, lies adjacent to the motor nucleus and fascicle of the facial nerve, the motor nucleus of the trigeminal nerve, the spinal Tract of the trigeminal nerve, the superior olivary nucleus, the Central Tegmental Tract, and the corticospinal Tract. The sixth nerve emerges from the brainstem between the pons and medulla, lateral to the pyramidal prominence. It then runs upwards along the ventral surface of the pons, lateral to the basilar artery, and passes between the pons and the anterior inferior cerebellar artery to ascend through the subarachnoid space along the clivus. It then pierces the dura mata, crosses around and through the inferior petrosal sinus, and passes under the petroclinoid (Gruber's ligament) in Dorello's canal to enter the cavernous sinus. In the cavernous sinus, the nerve bends laterally around the intracavernous segment of the internal carotid artery (ICA) and runs medial and parallel to the ophthalmic division (V1) of the trigeminal nerve. The ocular sympathetic fibers leave the ICA and join briefly with the abducens nerve before joining the ophthalmic division (V1) of the trigeminal nerve. Unlike the oculomotor (third nerve) and trochlear (fourth nerve), the abducens nerve does not lie within the lateral wall of the sinus, but rather it runs within the body of the sinus. The sixth nerve enters the orbit through the superior orbital fissure, passes through the annulus of Zinn, and innervates the lateral rectus muscle. See Ref (8) and (12) for full discussion.Review ref (8)Conservative1. Chen KS, Hung IJ, Lin KL. Isolated abducens nerve palsy: an unusual presentation of leukemia. J Child Neurol 2002;17:850-851. http://www.ncbi.nlm.nih.gov/pubmed/12585727 2. Currie JN, Lubin JH, Lessell S. Chronic isolated abducens paresis from tumors at the base of the brain. Arch Neurol 1983;40:226-229. http://www.ncbi.nlm.nih.gov/pubmed/6830471 3. Harada T, Ohashi T, Ohki K et al. Clival chordoma presenting as acute esotropia due to bilateral abducens palsy. Ophthalmologica 1997;21:109-111. http://www.ncbi.nlm.nih.gov/pubmed/9097318 4. Harbison JW, Lessell S, Selhorst JB. Neuro-ophthalmology of sphenoid sinus carcinoma. Brain 1984;108:855-870. http://www.ncbi.nlm.nih.gov/pubmed/6478180 5. Ikezaki K, Toda K, Abe M, Tabuchi K. Intracavernous epidermoid tumor presenting with abducens nerve paresis - case report. Neurologia Medico-Chirurgica 1992;32:360-364. http://www.ncbi.nlm.nih.gov/pubmed/1381064 6. Ilhan O, Sener EC, Ozyar E. Outcome of abducens nerve paralysis in patients with nasopharyngeal carcinoma. Eur J Ophthalmol 2002;12:55-59. http://www.ncbi.nlm.nih.gov/pubmed/11936446 7. Keane JR. Bilateral sixth nerve palsy. Analysis of 125 cases. Arch Neurol 1976;33:681-683. http://www.ncbi.nlm.nih.gov/pubmed/184766 8. Leigh RJ, Zee DS. Diagnosis of Peripheral Ocular Motor Palsies and Strabismus. Ch 9:385-474. In: The Neurology of Eye Movements, Fourth Edition. Oxford University Press, NY 2006. 9. Lopez R, David NJ, Gargano F, Post JD. Bilateral sixth nerve palsies in a patient with massive pituitary adenoma. Neurology 1981;31:1137-1138. http://www.ncbi.nlm.nih.gov/pubmed/7196535 10. Morioka T, Matsushima T, Yokoyama N. Muratami H, Fujii K, Fukui M. Isolated bilateral abducens nerve palsies caused by rupture of a vertebral artery aneurysm. J Clin Neuroopthalmol 1992;12:263-267. http://www.ncbi.nlm.nih.gov/pubmed/1287052 11. Volpe NJ, Liebach NJ, Munzenrider JE, Lessell S. Neuro-ophthalmological findings in chordoma and chondrosarcoma of the skull base. Am J Ophthalmol 1993;115:97-104. http://www.ncbi.nlm.nih.gov/pubmed/8420385 12. Wong AM. Nuclear and infranuclear ocular motor disorders. Chp 12:919-242. In: Eye Movement Disorders. Oxford University Press, 2008.curriculum_fellow; MTemspsixthabducens; MTemspsixthabducen