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Tadashi Kitahara - One of the best experts on this subject based on the ideXlab platform.
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Three-Dimensional Magnetic Resonance Imaging Reveals the Relationship Between the Control of Vertigo and Decreases in Endolymphatic Hydrops After Endolymphatic Sac Drainage With Steroids for Meniere's Disease
Frontiers Media S.A., 2019Co-Authors: Taeko Ito, Hiroshi Inui, Toshiteru Miyasaka, Tomoyuki Shiozaki, Shohei Matsuyama, Toshiaki Yamanaka, Kimihiko Kichikawa, Noriaki Takeda, Tadashi KitaharaAbstract:Meniere's disease is a common disease, that presents with recurrent vertigo and cochlear symptoms. The pathology of Meniere's disease was first reported to involve Endolymphatic hydrops in 1938. The Endolymphatic Sac is thought to have a role to keep the hydrostatic pressure and endolymph homeostasis for the inner ear. As a surgery for intractable Meniere's disease, Endolymphatic Sac drainage with intraEndolymphatic Sac application of large doses of steroids is performed to control the Endolymphatic hydrops and preserve or improve inner ear function. In the present study, to observe the effect of this surgery, we calculated the Endolymphatic space size using 3-Tesla magnetic resonance imaging (MRI) 4 h after intravenous injection of gadolinium enhancement at two time points: just before surgery and 2 years after. To reveal the condition of the Endolymphatic space, we constructed three-dimensional MR images semi-automatically and fused the three-dimensional images of the total fluid space of inner ear and the Endolymphatic space. After fusing the images, we calculated the volume of the total fluid space and Endolymphatic space. Two years after surgery, 16 of 20 patients (80.0%) showed relief from vertigo/dizziness and reductions in the ratio of the volume of the Endolymphatic size to the total fluid space of inner ear. Endolymphatic Sac drainage with intraEndolymphatic Sac application of large doses of steroids could control vertigo/dizziness and decrease the Endolymphatic hydrops. These results indicate that Endolymphatic Sac drainage is a good treatment option for patients with intractable Meniere's disease. In addition, volumetric measurement of inner ear volume could be useful for confirming the effect of treatments on Meniere's disease
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Endolymphatic Sac tumor with overexpression of v2 receptor mrna and inner ear hydrops
Acta Oto-laryngologica, 2011Co-Authors: Tadashi Kitahara, Chie Maekawa, Kaoru Kizawa, Takefumi Kamakura, Arata Horii, Hidenori InoharaAbstract:Abstract Conclusion: We reported previously that hyperactivation of vasopressin type-2 receptor (V2R)-mediated signaling in the Endolymphatic Sac could affect Endolymphatic fluid metabolism, resulting in the pathogenesis of Endolymphatic hydrops. Taken together with the present Endolymphatic Sac tumor (ELST) study, it is suggested that disorder of V2R signaling in the Endolymphatic Sac for any reason could be involved in the pathogenesis of Endolymphatic hydrops. Although it is due to tumor genesis in ELST, it is idiopathic in nature in Meniere's disease. Objective: We encountered two cases of ELST showing Meniere's disease-like symptoms. Both cases were suspected of having Endolymphatic hydrops using neuro-otological examinations. To clarify the histopathological diagnosis of ELST and the molecular pathogenesis of Endolymphatic hydrops, we performed histopathological and molecular biological examinations of the Endolymphatic Sac. Methods: ELSTs in two rare cases were removed completely through the transm...
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low tone air bone gaps after Endolymphatic Sac surgery
Auris Nasus Larynx, 2011Co-Authors: Tadashi Kitahara, Arata Horii, Takao Imai, Yasuo Mishiro, Takayuki Kawashima, Suetaka Nishiike, Hidenori InoharaAbstract:Abstract Objectives We detected chronic low-tone air-bone gaps (LTABGs) in some patients with Meniere's disease after Endolymphatic Sac surgery. The aim of the present study was to elucidate the mechanism of LTABGs after Endolymphatic Sac surgery. Methods We investigated 50 patients with Meniere's disease, who underwent surgery more than two years prior. LTABGs were defined as the three-tone-average = 20 dB formulated by ( a + b + c )/3, where a , b , and c are ABGs at 0.25, 0.5, and 1 kHz, respectively (ABG ±). The intra-operative finding was focused on identifying operculum (OPC ±). Results The ratio of post-operative ABG(+) was 50.0% (25/50). The ratio of intra-operative OPC(+) was 72.0% (36/50). The surgery results were as follows: the ratio of complete vertigo suppression (VS(+)) was 84.0% (42/50), air-conduction hearing gain (aHG(+)) was 40% (20/50), bone-conduction hearing gain (bHG(+)) was 64% (32/50), and speech discrimination gain (SDG(+)) was 28% (14/50). The post-operative ABG(+) was commonly observed in patients with intra-operative OPC(+) (chi-square test, p = 0.013). aHG(+) and SDG(+) results were related to the post-operative ABG(+) (chi-square test, p = 0.021 and p = 0.0018, respectively). Conclusions These data suggest that intra-operative OPC(+) may be causative for post-operative ABG(+), resulting in post-operative aHG(+) and SDG(+). Thus, as enlarged vestibular aqueduct syndrome and superior semicircular canal deficiency syndrome exhibit LTABGs due to the third mobile inner ear window, Endolymphatic Sac surgery with adequate Endolymphatic Sac decompression and exposure to high doses of steroids, might induce LTABGs and the beneficial results of Endolymphatic Sac surgery.
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expression and translocation of aquaporin 2 in the Endolymphatic Sac in patients with meniere s disease
Journal of Neuroendocrinology, 2010Co-Authors: Chie Maekawa, Tadashi Kitahara, Kaoru Kizawa, Takefumi Kamakura, Arata Horii, Hidenori Inohara, Suzuyo Okazaki, Takao Imai, Katsumi Doi, Hiroshi KiyamaAbstract:Meniere's disease, characterised by episodic vertigo, fluctuating hearing loss and tinnitus, can occur under conditions of stress. Its pathology was first revealed to be inner ear hydrops through temporal bone studies in 1938. Although its pathogenesis has been proposed to be a disorder of water transport in the inner ear, subsequently, it remains unsolved, until now. A recent study revealed that both plasma stress hormone, vasopressin (pAVP) and its receptor, V2 (V2R) expression in the inner ear Endolymphatic Sac were significantly higher in Meniere's patients. In the present study, to link V2R-related molecules and inner ear hydrops, we examined V2R-linked water channel molecule, aquaporin-2 (AQP2) expression and translocation in human Endolymphatic Sac. AQP2 mRNA expression in the Endolymphatic Sac was significantly higher in Meniere's patients by using real-time polymerase chain reaction, as further confirmed by western blotting. AQP2-like immunoreactivity (-LIR) was translocated from luminal to baso-lateral side with endosomal trapping in the Endolymphatic Sac at the time of AVP exposure in human Endolymphatic Sac tissue culture. The similar AQP2-LIR translocation was also demonstrated by forskolin and blocked by vasopressin/V2R specific antagonist, OPC31260 and protein kinase A (PKA) specific antagonists, H-89 and KT-5720. We concluded that in the pathogenesis of inner ear hydrops resulting in Meniere's attacks, pAVP elevation as a result of stress and subsequent V2R-cAMP-PKA-AQP2 activation and endosomal trapping of AQP2 in the Endolymphatic Sac, might be important as a basis of this disease. Further experimental and clinical studies are needed to better clarify the neuroscientific relationship between stress and Meniere's disease.
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effects of Endolymphatic Sac drainage with steroids for intractable meniere s disease a long term follow up and randomized controlled study
Laryngoscope, 2008Co-Authors: Tadashi Kitahara, Takeshi Kubo, Shinichi Okumura, Masaaki KitaharaAbstract:Objective: Meniere's disease is a common inner ear disease with an incidence of 15 to 50 per 100,000 population. Since Meniere's disease is thought to be triggered by an immune insult to the inner ear, we examined intraEndolymphatic Sac application of steroids as a new therapeutic strategy for intractable Meniere's disease. Study Design: Prospective randomized controlled study. Methods: Between 1996 and 2005, we enrolled and assigned 197 intractable Meniere's patients to three groups in a randomized controlled trial: Group I (G-I)— patients who underwent Endolymphatic Sac drainage and steroid-instillation; Group II (G-II)—those who underwent Endolymphatic Sac drainage without steroid-instillation; and Group III (G-III)—those who declined Endolymphatic Sac drainage. Definitive spells and hearing in all three groups were determined for 2 to 7 years after treatment. Results: According to the 1995 American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS) criteria, 2-year results demonstrated that vertigo was completely controlled in 88.0% of patients in G-I (n = 100), 85.1% of patients in G-II (n = 47), and 8.0% in G-III (n = 50). Statistically, G-I = G-II>G-III. Hearing was improved in 49.0% of patients in G-I, 31.9% in G-II, and 6.0% in G-III (G-I>G-II>G-III). Results after 7 years showed that vertigo was completely controlled in 78.8% of patients in G-I, 79.2% in G-II, and 25.0% in G-III (G-I = G-II>G-III). Hearing improved in 36.5% of patients in G-I, 8.3% in G-II, and 0.0% in G-III (G-I>G-II = G-III). Conclusions: From non-surgical observation in G-III for at least 7 years after treatment, steroids instilled into Endolymphatic Sac in G-I patients significantly improved hearing in intractable Meniere's patients, more so than Endolymphatic Sac drainage without steroids in G-II patients.
Tracy Miesner - One of the best experts on this subject based on the ideXlab platform.
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SLC26A4 Targeted to the Endolymphatic Sac Rescues Hearing and Balance in Slc26a4 Mutant Mice
2016Co-Authors: Joel D. Sanneman, Donald G. Harbidge, Fei Zhou, Taku Ito, Raoul Nelson, Nicolas Picard, Dominique Eladari, Tracy Miesner, Andrew J. GriffithAbstract:Mutations of SLC26A4 are a common cause of human hearing loss associated with enlargement of the vestibular aqueduct. SLC26A4 encodes pendrin, an anion exchanger expressed in a variety of epithelial cells in the cochlea, the vestibular labyrinth and the Endolymphatic Sac. Slc26a4D/D mice are devoid of pendrin and develop a severe enlargement of the membranous labyrinth, fail to acquire hearing and balance, and thereby provide a model for the human phenotype. Here, we generated a transgenic mouse line that expresses human SLC26A4 controlled by the promoter of ATP6V1B1. Crossing this transgene into the Slc26a4D/D line restored protein expression of pendrin in the Endolymphatic Sac without inducing detectable expression in the cochlea or the vestibular sensory organs. The transgene prevented abnormal enlargement of the membranous labyrinth, restored a normal endocochlear potential, normal pH gradients between endolymph and perilymph in the cochlea, normal otoconia formation in the vestibular labyrinth and normal sensory functions of hearing and balance. Our study demonstrates that restoration of pendrin to the Endolymphatic Sac is sufficient to restore normal inner ear function. This finding in conjunction with our previous report that pendrin expression is required for embryonic development but not for the maintenance of hearing opens the prospect that a spatially and temporally limited therapy wil
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SLC26A4 targeted to the Endolymphatic Sac rescues hearing and balance in Slc26a4 mutant mice.
PLoS genetics, 2013Co-Authors: Joel D. Sanneman, Raoul D. Nelson, Donald G. Harbidge, Fei Zhou, Taku Ito, Nicolas Picard, Dominique Eladari, Régine Chambrey, Tracy MiesnerAbstract:Mutations of SLC26A4 are a common cause of human hearing loss associated with enlargement of the vestibular aqueduct. SLC26A4 encodes pendrin, an anion exchanger expressed in a variety of epithelial cells in the cochlea, the vestibular labyrinth and the Endolymphatic Sac. Slc26a4Δ/Δ mice are devoid of pendrin and develop a severe enlargement of the membranous labyrinth, fail to acquire hearing and balance, and thereby provide a model for the human phenotype. Here, we generated a transgenic mouse line that expresses human SLC26A4 controlled by the promoter of ATP6V1B1. Crossing this transgene into the Slc26a4Δ/Δ line restored protein expression of pendrin in the Endolymphatic Sac without inducing detectable expression in the cochlea or the vestibular sensory organs. The transgene prevented abnormal enlargement of the membranous labyrinth, restored a normal endocochlear potential, normal pH gradients between endolymph and perilymph in the cochlea, normal otoconia formation in the vestibular labyrinth and normal sensory functions of hearing and balance. Our study demonstrates that restoration of pendrin to the Endolymphatic Sac is sufficient to restore normal inner ear function. This finding in conjunction with our previous report that pendrin expression is required for embryonic development but not for the maintenance of hearing opens the prospect that a spatially and temporally limited therapy will restore normal hearing in human patients carrying a variety of mutations of SLC26A4.
Alfio Ferlito - One of the best experts on this subject based on the ideXlab platform.
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Current Treatment of Endolymphatic Sac Tumor of the Temporal Bone
Advances in Therapy, 2018Co-Authors: William M. Mendenhall, Carlos Suárez, Alena Skálová, Primož Strojan, Asterios Triantafyllou, Kenneth O. Devaney, Michelle D. Williams, Alessandra Rinaldo, Alfio FerlitoAbstract:An Endolymphatic Sac tumor (ELST) is a rare, indolent but locally aggressive tumor arising in the posterior petrous ridge. Patients present with sensorineural hearing loss and tinnitus. As the tumor progresses, patients may experience vertigo, ataxia, facial nerve paresis, pain and otorrhea. Most patients present in their 4th or 5th decade with a wide age range. Patients with von Hippel–Lindau disease have an increased likelihood of developing ELST. Histologically, ELST is a low-grade adenocarcinoma. As it progresses, it destroys bone and extends into adjacent tissues. The likelihood of regional or distant metastases is remote. The optimal treatment is resection with negative margins. Patients with positive margins, gross residual disease, or unresectable tumor are treated with radiotherapy or radiosurgery. Late recurrences are common, so long follow-up is necessary to assess efficacy. The likelihood of cure depends on tumor extent and is probably in the range of 50–75%.
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Endolymphatic Sac tumor (low-grade papillary adenocarcinoma) of the temporal bone.
Acta oto-laryngologica, 2003Co-Authors: Kenneth O. Devaney, Alfio Ferlito, Alessandra RinaldoAbstract:The entity which has come to be known as an Endolymphatic Sac tumor (ELST) has, in the past, been known as adenocarcinoma of Endolymphatic Sac origin, aggressive papillary tumor of the temporal bone and Heffner's tumor. ELSTs arise in the vicinity of the inner ear and may extend to involve both the posterior fossa as well as the middle ear and the external ear canal, which may complicate the differential diagnosis ELSTs are typically seen in adults, with only rare descriptions in pediatric patients. They may be sporadic tumors or they may arise as part of the symptom complex of von Hippel-Lindau disease. Clinical signs at presentation range from a mass in the external ear canal to sensorineural deafness to cranial nerve palsies. Imaging studies reveal a destructive lesion of the petrous bone which is heterogeneous on MR scanning. Light microscopy reveals two chief patterns: a follicular pattern, reminiscent of thyroid parenchyma; and a papillary/solid pattern. Both patterns are often admixed in the same tumor, and the individual tumor cells are cytologically bland. Immunohistochemically, ELSTs are typically keratin-, vimentin- and epithelial membrane antigen-positive; they are often S-100 protein-positive and neuron-specific enolase-positive as well. ELSTs are difficult to extirpate surgically (owing to their locally aggressive nature); nevertheless, surgical excision remains the mainstay of current therapy. These are slow-growing (albeit locally aggressive) tumors which have only rarely been reported to metastasize; as such, they remain principally a problem of local control.
Alessandra Rinaldo - One of the best experts on this subject based on the ideXlab platform.
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Current Treatment of Endolymphatic Sac Tumor of the Temporal Bone
Advances in Therapy, 2018Co-Authors: William M. Mendenhall, Carlos Suárez, Alena Skálová, Primož Strojan, Asterios Triantafyllou, Kenneth O. Devaney, Michelle D. Williams, Alessandra Rinaldo, Alfio FerlitoAbstract:An Endolymphatic Sac tumor (ELST) is a rare, indolent but locally aggressive tumor arising in the posterior petrous ridge. Patients present with sensorineural hearing loss and tinnitus. As the tumor progresses, patients may experience vertigo, ataxia, facial nerve paresis, pain and otorrhea. Most patients present in their 4th or 5th decade with a wide age range. Patients with von Hippel–Lindau disease have an increased likelihood of developing ELST. Histologically, ELST is a low-grade adenocarcinoma. As it progresses, it destroys bone and extends into adjacent tissues. The likelihood of regional or distant metastases is remote. The optimal treatment is resection with negative margins. Patients with positive margins, gross residual disease, or unresectable tumor are treated with radiotherapy or radiosurgery. Late recurrences are common, so long follow-up is necessary to assess efficacy. The likelihood of cure depends on tumor extent and is probably in the range of 50–75%.
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Endolymphatic Sac tumor (low-grade papillary adenocarcinoma) of the temporal bone.
Acta oto-laryngologica, 2003Co-Authors: Kenneth O. Devaney, Alfio Ferlito, Alessandra RinaldoAbstract:The entity which has come to be known as an Endolymphatic Sac tumor (ELST) has, in the past, been known as adenocarcinoma of Endolymphatic Sac origin, aggressive papillary tumor of the temporal bone and Heffner's tumor. ELSTs arise in the vicinity of the inner ear and may extend to involve both the posterior fossa as well as the middle ear and the external ear canal, which may complicate the differential diagnosis ELSTs are typically seen in adults, with only rare descriptions in pediatric patients. They may be sporadic tumors or they may arise as part of the symptom complex of von Hippel-Lindau disease. Clinical signs at presentation range from a mass in the external ear canal to sensorineural deafness to cranial nerve palsies. Imaging studies reveal a destructive lesion of the petrous bone which is heterogeneous on MR scanning. Light microscopy reveals two chief patterns: a follicular pattern, reminiscent of thyroid parenchyma; and a papillary/solid pattern. Both patterns are often admixed in the same tumor, and the individual tumor cells are cytologically bland. Immunohistochemically, ELSTs are typically keratin-, vimentin- and epithelial membrane antigen-positive; they are often S-100 protein-positive and neuron-specific enolase-positive as well. ELSTs are difficult to extirpate surgically (owing to their locally aggressive nature); nevertheless, surgical excision remains the mainstay of current therapy. These are slow-growing (albeit locally aggressive) tumors which have only rarely been reported to metastasize; as such, they remain principally a problem of local control.
J M Tubiana - One of the best experts on this subject based on the ideXlab platform.
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papillary adenoma of Endolymphatic Sac origin a temporal bone tumor in von hippel lindau disease case report
Journal of Neurosurgery, 1997Co-Authors: J C Ouallet, K Marsotdupuch, R Van Effenterre, M Kujas, J M TubianaAbstract:This report describes a patient with von Hippel-Lindau disease who presented with an 8-year history of a slow-growing, locally invasive vascularized lesion of the temporal bone involving the cerebellopontine angle. The mass, studied by computerized tomography scanning and magnetic resonance imaging techniques, was partly cystic in appearance. After removal of the mass, pathological studies confirmed a papillary cystic tumor with characteristics that have been described in tumors with an Endolymphatic Sac origin. These rare neoplasms constitute a distinct pathological entity and deserve wider recognition.