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Jeongmin Hwang - One of the best experts on this subject based on the ideXlab platform.
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association of lateral rectus muscle volume and ocular motility with the Abducens Nerve in duane s retraction syndrome
Graefes Archive for Clinical and Experimental Ophthalmology, 2021Co-Authors: Jeongmin Hwang, Hee Kyung Yang, Jounghan Kim, Daeseung LeeAbstract:PURPOSE To investigate the relationship between ocular motility and lateral rectus (LR) muscle volume according to the presence or absence of the Abducens Nerve in patients with Duane's retraction syndrome (DRS) using high-resolution magnetic resonance imaging (MRI). METHODS A total of 54 unilateral DRS patients were divided into two groups according to high-resolution MRI findings: DRS without an Abducens Nerve on the affected side (absent CN6 group, n = 45) and DRS with symmetric Abducens Nerves on both sides (present CN6 group, n = 9). Ocular motility was measured by image analysis based on nine gaze photographs. LR volume was measured on T2-weighted coronal MRI of the orbit, and the ratio of paretic/normal side (P/N) LR volume was investigated. Association of the Abducens Nerve with various parameters including ocular motility, LR volume, and ratios of P/N LR volume were determined. RESULTS LR volume was smaller in the affected eye than the non-affected eye in both groups. In the present CN6 group, Abducens Nerve diameter and the ratio of P/N LR volume showed a positive correlation. A smaller LR volume and more limitation of abduction in the affected eye were predictive of an absent Abducens Nerve in DRS. CONCLUSIONS LR muscle hypoplasia was apparent in the affected eye of DRS patients. Abducens Nerve diameter positively correlated with the ratio of P/N LR volume in the present CN6 group. Graphical abstract.
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postoperative full abduction in a patient of duane retraction syndrome without an Abducens Nerve a case report
BMC Ophthalmology, 2017Co-Authors: Jae Hyoung Kim, Jeongmin HwangAbstract:Duane retraction syndrome (DRS) consists of abduction deficit, globe retraction and upshoots or downshoots with adduction. The Abducens Nerve on the affected side is absent in type 1 DRS. After bilateral medial rectus muscle recession in unilateral type 1 DRS may improve the abduction limitation, but still more than −3 limitation remains. A 6-month-old boy presented with esotropia which had been noticed in early infancy. He showed limited abduction, fissure narrowing on attempted adduction and a small upshoot OS. Left Abducens Nerve was not identified on magnetic resonance imaging compatible with Duane retraction syndrome type 1. He showed full abduction after bilateral medial rectus recession of 6.0 mm at the age of 9 months, and remained orthotropia with full abduction OU 2 years postoperatively. He is my only patient with Duane retraction syndrome who showed full abduction after bilateral medial rectus recession. A patient with the type 1 Duane retraction syndrome rarely may show full abduction after bilateral medial rectus recession mimicking infantile esotropia.
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Horner’s Syndrome and Contralateral Abducens Nerve Palsy Associated with Zoster Meningitis
2016Co-Authors: Bum-joo Cho, Ji-soo Kim, Jeongmin HwangAbstract:Horner’s syndrome, first described by Johann Friedrich Horner in 1929, is characterized by the classic triad of mi-osis, ipsilateral blepharoptosis, and facial anhidrosis [1]. It can be caused by a viral infection, trauma, carotid dissec-tion, or a tumor which interrupts the sympathetic innerva-tion to the eyes and ocular adnexae [1]. Although the syn-drome usually manifests by itself, it occasionally presents with other conditions such as ipsilateral Abducens Nerve palsy or herpes zoster ophthalmicus [2,3]. Many research-ers have described the concurrence of Horner’s syndrome and ipsilateral Abducens Nerve palsy [4-6], and the under-lying causes were primary or metastatic tumors in the cav-ernous sinus, sphenodial sinus cyst, carotid aneurysm, or viral infections [2,3,7,8]. Herein, we describe a case of Horner’s syndrome associ
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Abducens Nerve in patients with type 3 duane s retraction syndrome
PLOS ONE, 2016Co-Authors: Hee Kyung Yang, Jae Hyoung Kim, Jeongmin HwangAbstract:Background We have previously reported that the presence of the Abducens Nerve was variable in patients with type 3 Duane’s retraction syndrome (DRS), being present in 2 of 5 eyes (40%) and absent in 3 (60%) on magnetic resonance imaging (MRI). The previous study included only 5 eyes with unilateral DRS type 3. Objectives To supplement existing scarce pathologic information by evaluating the presence of the Abducens Nerve using high resolution thin-section MRI system in a larger number of patients with DRS type 3, thus to provide further insight into the pathogenesis of DRS. Data Extraction A retrospective review of medical records on ophthalmologic examination and high resolution thin-section MRI at the brainstem level and orbit was performed. A total of 31 patients who showed the typical signs of DRS type 3, including abduction and adduction deficit, globe retraction, narrowing of fissure on adduction and upshoot and/or downshoot, were included. The Abducens Nerve and any other extraocular muscle abnormalities discovered by MRI were noted. Results DRS was unilateral in 26 patients (84%) and bilateral in 5 patients (16%). Two out of 5 bilateral patients had DRS type 3 in the right eye and DRS type 1 in the left eye. Of the 34 affected orbits with DRS type 3 in 31 patients, the Abducens Nerve was absent or hypoplastic in 31 eyes (91%) and present in 3 eyes (9%). Patients with a present Abducens Nerve showed more limitation in adduction compared to patients with an absent Abducens Nerve (P = 0.030). Conclusions The Abducens Nerve is absent or hypoplastic in 91% of DRS type 3. Patients with a present Abducens Nerve showed more prominent limitation of adduction. As DRS type 3 partly share the same pathophysiology with type 1 and 2 DRS, the classification of DRS may have to be revised according to MRI findings.
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Clinical manifestations of patients with type 3 Duane retraction syndrome were compared between patients with a present Abducens Nerve (present group) and absent/hypoplastic Abducens Nerve (absent or hypoplastic group).
2016Co-Authors: Hee Kyung Yang, Jae Hyoung Kim, Jeongmin HwangAbstract:Clinical manifestations of patients with type 3 Duane retraction syndrome were compared between patients with a present Abducens Nerve (present group) and absent/hypoplastic Abducens Nerve (absent or hypoplastic group).
Jae Hyoung Kim - One of the best experts on this subject based on the ideXlab platform.
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postoperative full abduction in a patient of duane retraction syndrome without an Abducens Nerve a case report
BMC Ophthalmology, 2017Co-Authors: Jae Hyoung Kim, Jeongmin HwangAbstract:Duane retraction syndrome (DRS) consists of abduction deficit, globe retraction and upshoots or downshoots with adduction. The Abducens Nerve on the affected side is absent in type 1 DRS. After bilateral medial rectus muscle recession in unilateral type 1 DRS may improve the abduction limitation, but still more than −3 limitation remains. A 6-month-old boy presented with esotropia which had been noticed in early infancy. He showed limited abduction, fissure narrowing on attempted adduction and a small upshoot OS. Left Abducens Nerve was not identified on magnetic resonance imaging compatible with Duane retraction syndrome type 1. He showed full abduction after bilateral medial rectus recession of 6.0 mm at the age of 9 months, and remained orthotropia with full abduction OU 2 years postoperatively. He is my only patient with Duane retraction syndrome who showed full abduction after bilateral medial rectus recession. A patient with the type 1 Duane retraction syndrome rarely may show full abduction after bilateral medial rectus recession mimicking infantile esotropia.
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Abducens Nerve in patients with type 3 duane s retraction syndrome
PLOS ONE, 2016Co-Authors: Hee Kyung Yang, Jae Hyoung Kim, Jeongmin HwangAbstract:Background We have previously reported that the presence of the Abducens Nerve was variable in patients with type 3 Duane’s retraction syndrome (DRS), being present in 2 of 5 eyes (40%) and absent in 3 (60%) on magnetic resonance imaging (MRI). The previous study included only 5 eyes with unilateral DRS type 3. Objectives To supplement existing scarce pathologic information by evaluating the presence of the Abducens Nerve using high resolution thin-section MRI system in a larger number of patients with DRS type 3, thus to provide further insight into the pathogenesis of DRS. Data Extraction A retrospective review of medical records on ophthalmologic examination and high resolution thin-section MRI at the brainstem level and orbit was performed. A total of 31 patients who showed the typical signs of DRS type 3, including abduction and adduction deficit, globe retraction, narrowing of fissure on adduction and upshoot and/or downshoot, were included. The Abducens Nerve and any other extraocular muscle abnormalities discovered by MRI were noted. Results DRS was unilateral in 26 patients (84%) and bilateral in 5 patients (16%). Two out of 5 bilateral patients had DRS type 3 in the right eye and DRS type 1 in the left eye. Of the 34 affected orbits with DRS type 3 in 31 patients, the Abducens Nerve was absent or hypoplastic in 31 eyes (91%) and present in 3 eyes (9%). Patients with a present Abducens Nerve showed more limitation in adduction compared to patients with an absent Abducens Nerve (P = 0.030). Conclusions The Abducens Nerve is absent or hypoplastic in 91% of DRS type 3. Patients with a present Abducens Nerve showed more prominent limitation of adduction. As DRS type 3 partly share the same pathophysiology with type 1 and 2 DRS, the classification of DRS may have to be revised according to MRI findings.
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Clinical manifestations of patients with type 3 Duane retraction syndrome were compared between patients with a present Abducens Nerve (present group) and absent/hypoplastic Abducens Nerve (absent or hypoplastic group).
2016Co-Authors: Hee Kyung Yang, Jae Hyoung Kim, Jeongmin HwangAbstract:Clinical manifestations of patients with type 3 Duane retraction syndrome were compared between patients with a present Abducens Nerve (present group) and absent/hypoplastic Abducens Nerve (absent or hypoplastic group).
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Abducens Nerve is present in patients with type 2 duane s retraction syndrome
Ophthalmology, 2012Co-Authors: Jae Hyoung Kim, Jeongmin HwangAbstract:Objective To determine whether the Abducens Nerve is present in patients with type 2 Duane's retraction syndrome (DRS). Design Retrospective, observational case series. Participants Twelve consecutive patients diagnosed with type 2 DRS. Methods A retrospective review of medical records of ophthalmologic examination and thin-sectioned magnetic resonance imaging (MRI) at the brainstem level and the orbit was performed on 12 patients who showed the typical signs of type 2 DRS, including adduction deficit; globe retraction; narrowing of fissure on adduction; and upshoot, downshoot, or both. Main Outcome Measures Presence of the Abducens Nerve and any other extraocular muscle abnormalities discovered by MRI scan. Results Magnetic resonance imaging revealed the presence of the Abducens Nerve in all the affected eyes (n = 13) of 12 patients with type 2 DRS. Conclusions The Abducens Nerve is present on the affected side in type 2 Duane's retraction syndrome. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.
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hypoplastic oculomotor Nerve and absent Abducens Nerve in congenital fibrosis syndrome and synergistic divergence with magnetic resonance imaging
Ophthalmology, 2005Co-Authors: Jae Hyoung Kim, Jeongmin HwangAbstract:Objective There is only one neuropathologic report of congenital fibrosis of the extraocular muscles (CFEOM), and none of synergistic divergence. The aim of this report was to study the oculomotor Nerve and the Abducens Nerve in 2 such patients with magnetic resonance imaging. Design Observational case reports. Methods Ophthalmologic examination and thin-sectioned magnetic resonance imaging across the brainstem level were performed in 2 patients with CFEOM and synergistic divergence. To confirm the accuracy of the procedure, we compared the results obtained with those of a control group of 40 individuals using the same technique. Main Outcome Measures The oculomotor Nerve and the Abducens Nerve on magnetic resonance imaging. Results Magnetic resonance imaging disclosed bilateral hypoplasia of the oculomotor Nerve in both patients, and absence of the Abducens Nerve on the affected side of synergistic divergence. The oculomotor and Abducens Nerves were observed in 80 of 80 eyes (100%) screened as controls. Conclusions In both patients with CFEOM and synergistic divergence, the oculomotor Nerve was hypoplastic bilaterally, and the Abducens Nerve was absent on the side exhibiting synergistic divergence.
Hee Kyung Yang - One of the best experts on this subject based on the ideXlab platform.
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association of lateral rectus muscle volume and ocular motility with the Abducens Nerve in duane s retraction syndrome
Graefes Archive for Clinical and Experimental Ophthalmology, 2021Co-Authors: Jeongmin Hwang, Hee Kyung Yang, Jounghan Kim, Daeseung LeeAbstract:PURPOSE To investigate the relationship between ocular motility and lateral rectus (LR) muscle volume according to the presence or absence of the Abducens Nerve in patients with Duane's retraction syndrome (DRS) using high-resolution magnetic resonance imaging (MRI). METHODS A total of 54 unilateral DRS patients were divided into two groups according to high-resolution MRI findings: DRS without an Abducens Nerve on the affected side (absent CN6 group, n = 45) and DRS with symmetric Abducens Nerves on both sides (present CN6 group, n = 9). Ocular motility was measured by image analysis based on nine gaze photographs. LR volume was measured on T2-weighted coronal MRI of the orbit, and the ratio of paretic/normal side (P/N) LR volume was investigated. Association of the Abducens Nerve with various parameters including ocular motility, LR volume, and ratios of P/N LR volume were determined. RESULTS LR volume was smaller in the affected eye than the non-affected eye in both groups. In the present CN6 group, Abducens Nerve diameter and the ratio of P/N LR volume showed a positive correlation. A smaller LR volume and more limitation of abduction in the affected eye were predictive of an absent Abducens Nerve in DRS. CONCLUSIONS LR muscle hypoplasia was apparent in the affected eye of DRS patients. Abducens Nerve diameter positively correlated with the ratio of P/N LR volume in the present CN6 group. Graphical abstract.
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Abducens Nerve in patients with type 3 duane s retraction syndrome
PLOS ONE, 2016Co-Authors: Hee Kyung Yang, Jae Hyoung Kim, Jeongmin HwangAbstract:Background We have previously reported that the presence of the Abducens Nerve was variable in patients with type 3 Duane’s retraction syndrome (DRS), being present in 2 of 5 eyes (40%) and absent in 3 (60%) on magnetic resonance imaging (MRI). The previous study included only 5 eyes with unilateral DRS type 3. Objectives To supplement existing scarce pathologic information by evaluating the presence of the Abducens Nerve using high resolution thin-section MRI system in a larger number of patients with DRS type 3, thus to provide further insight into the pathogenesis of DRS. Data Extraction A retrospective review of medical records on ophthalmologic examination and high resolution thin-section MRI at the brainstem level and orbit was performed. A total of 31 patients who showed the typical signs of DRS type 3, including abduction and adduction deficit, globe retraction, narrowing of fissure on adduction and upshoot and/or downshoot, were included. The Abducens Nerve and any other extraocular muscle abnormalities discovered by MRI were noted. Results DRS was unilateral in 26 patients (84%) and bilateral in 5 patients (16%). Two out of 5 bilateral patients had DRS type 3 in the right eye and DRS type 1 in the left eye. Of the 34 affected orbits with DRS type 3 in 31 patients, the Abducens Nerve was absent or hypoplastic in 31 eyes (91%) and present in 3 eyes (9%). Patients with a present Abducens Nerve showed more limitation in adduction compared to patients with an absent Abducens Nerve (P = 0.030). Conclusions The Abducens Nerve is absent or hypoplastic in 91% of DRS type 3. Patients with a present Abducens Nerve showed more prominent limitation of adduction. As DRS type 3 partly share the same pathophysiology with type 1 and 2 DRS, the classification of DRS may have to be revised according to MRI findings.
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Clinical manifestations of patients with type 3 Duane retraction syndrome were compared between patients with a present Abducens Nerve (present group) and absent/hypoplastic Abducens Nerve (absent or hypoplastic group).
2016Co-Authors: Hee Kyung Yang, Jae Hyoung Kim, Jeongmin HwangAbstract:Clinical manifestations of patients with type 3 Duane retraction syndrome were compared between patients with a present Abducens Nerve (present group) and absent/hypoplastic Abducens Nerve (absent or hypoplastic group).
Bulent Sam - One of the best experts on this subject based on the ideXlab platform.
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the mechanism of injury of the Abducens Nerve in severe head trauma a postmortem study
Forensic Science International, 2004Co-Authors: Bulent Sam, Mehmet Faik Ozveren, Ismail Akdemir, Cahide Topsakal, Bengu Cobanoglu, Cetin Lutfi Baydar, Ozer UlukanAbstract:The aim of this study is to investigate the mechanism of injury of Abducens Nerve at petroclival region in severe head trauma. Twenty specimens provided from 10 autopsied cases due to severe head trauma were investigated macroscopically and histopathogically. The slices of the Abducens Nerve taken consecutively along its course at petroclival region were stained with Hematoxylline-Eosin and evaluated under light microscope. In addition, coexisting cervical injuries in these cases were assessed macroscopically. Edema and perineural hemorrhagia of Abducens Nerve were identified in all cases. Nerve injury was found more exaggerated at the sites of dural entry point and petrous apex than any other parts of the Abducens Nerve. Furthermore, microscopically, also remarkable perineural hemorrhage of the Abducens Nerve was observed at the site of its anastomoses with the sympathetic plexus on the lateral wall of the internal carotid artery (ICA). Abducens Nerve is injured at the sites of dural entry point, petrous apex and lateral wall of the ICA, directly proportional with the severity of the trauma. This finding is also significant in verification of the severe head trauma.
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duplication of the Abducens Nerve at the petroclival region an anatomic study
Neurosurgery, 2003Co-Authors: Faik M Ozveren, Bulent Sam, Ismail Akdemir, Alpay Alkan, Ibrahim Tekdemir, Haluk DedaAbstract:OBJECTIVE: During its course between the brainstem and the lateral rectus muscle, the Abducens Nerve usually travels forward as a single trunk, but it is not uncommon for the Nerve to split into two branches, The objective of this study was to establish the incidence and the clinical importance of the duiplication of the Nerve METHODS: The study was performed on 100 sides of 50 autopsy materioals. in 10 of 11 cases of duplicated Abducens Nerve, colored latex was injected into the common carotid arteries and the internal jugular veins. The remaining case was used for bistological examination. RESULTS: four of 50 cases had duplicated Abducens Nerve bilatecally. In seves cases, the duplicated Abducens Nerve was unilateral. In 9 of these 15 specimens, the Abducens Nerve emerged from the brainstem as a single trunk, entered the subarachnoid space, split into two branches, merged again in the cavernous sinus, and innervated the lateral rectus muscle as a single trunk. In six specimens, conversely, the Abducens Nerve exited the pontomedullary suicus as two separate cadices but joined in the cavernous sinus to innervate the lateral rectas muscle. in 13 specimens, both branches of the Nerve passed beneath the petrosphenoidal ligament. In two specimens, one of the branches passed under the ligament and the other passed over it. In one of these last two specimens, one branch passed over the petrosphenoidal ligament and the other through a bony canal formed by the petrous apex and the superolateral border of the clivus. In all of the specimens, both brauches were wrapped by two layers: an inner layer made up of the arachnoid membrane and an outer layer composed of the dura during its course between their dural openings and the lateral wall of the cavernous segment of the internal carotid artery, This finding was also confirmed by histological examination in one specimen. CONCLUSION: Double abduceos Nerve is is not a rate variation, keping such variations in mind could spare us from injuring the Vith cranial Nerve during cranlal base operations and transvenous endovascular interventions.
William F Hoyt - One of the best experts on this subject based on the ideXlab platform.
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absence of the Abducens Nerve in duane syndrome verified by magnetic resonance imaging
American Journal of Ophthalmology, 1998Co-Authors: Cameron F Parsa, Ellen P Grant, William P Dillon, Sascha Du Lac, William F HoytAbstract:Purpose To demonstrate that currently available magnetic resonance imaging techniques may verify the absence of the Abducens Nerve in Duane syndrome. Methods We performed magnetic resonance imaging in a 36-year-old woman with left Duane syndrome, type 1, using spoiled gradient recalled acquisition in the steady state to obtain high-resolution T1-weighted images through the Abducens Nerve in its subarachnoid segment. Scans were obtained in the axial plane from the medulla to the midbrain and then reformatted along the plane of the Abducens Nerve. Result Unilateral absence of the left Abducens Nerve was verified using magnetic resonance imaging. Conclusion The absence of the Abducens Nerve in Duane syndrome can be verified by modern magnetic resonance imaging techniques.
