Yoshihiko Okinaka

Progress of caloric response of vestibular neuronitis

Progress of caloric response and subjective symptoms of 60 patients with vestibular neuronitis was evaluated by a long term follow-up study. Normalization of caloric responses was confirmed in 25 (41.7%) out of 60 patients, 20 of whom had recovered within 2 years of the onset of vertigo. The rate of the patients with canal paresis was about 90% after 1 month of the onset, and 80% after 6 months, while 50% of them still showed canal paresis after 5 or 10 years had passed. Complete relief from subjective symptoms was recognized in 34 (56.7%) cases during the follow-up period. We conclude that the prognosis of vestibular neuronitis is not always good, because vestibular function did not recover within normal levels in about half of the patients in spite of complete relief from subjective symptoms in many of them.

Orbital Blowout Fracture with Persistent Mobility Deficit Due to Fibrosis of the Inferior Rectus Muscle and Perimuscular Tissue

A case of orbital blowout fracture accompanied by fibrosis of the inferior rectus muscle resulting in an irreversible orbital mobility deficit is reported. An 8-year-old girl with an orbital blowout fracture was treated with steroids for 10 days, as with other cases in our department. She exhibited a disturbance of vertical eye movement and a positive forced duction test result. Although surgery was performed on day 13, and on day 27 due to poor recovery after the first operation, almost no improvement of the ocular movement was noted. The results of a traction test, performed during the second operation, suggested that the inferior rectus muscle had adhered to the periosteum. Magnetic resonance imaging performed 3 days after the second operation revealed fibrosis of the inferior rectus muscle and perimuscular tissue, resulting in an irreversible disturbance of the vertical ocular movement. The present findings suggest that the need for and timing of surgery in patients with blowout fractures should be determined on an individual basis.

Serovirological Study of Vestibular Neuronitis

A serovirological study to clarify the pathogenesis of vestibular neuronitis was made on 44 patients. The diagnosis of vestibular neuronitis was made under the diagnostic criteria. Sera from all 44 cases were collected twice or more at defined intervals. Of these, 36 cases were treated as paired sera. Seventeen out of 36 paired cases showed significant change in serum viral antibody titer (HSV, 2 cases; CMV, 1 case; EBV, 7 cases; rubella, 2 cases; adeno., 2 cases; influ. A, 1 case; influ. B, 2 cases). It was assumed that infection caused by these detected viruses played an important role in the onset of vertigo in each case.

Optic Neuropathy Caused by an Isolated Mucocele in an Onodi Cell

A rare case of retrobulbar optic neuropathy caused by an isolated mucocele in an Onodi cell is presented. A 63-year-old man suffering from left recurrent optic neuropathy had shown improved visual acuity with steroid treatment at the age of 48 and 56 years. Impaired visual acuity and blurred vision in the left eye appeared again, and a marked inferior decrease in the left visual field was noted. Although axial computed tomography (CT) showed no abnormal findings, magnetic resonance imaging (MRI) revealed a small squamous-shaped lesion (17 × 17 × 7.3 mm) in the left posterior ethmoidal air cell (Onodi cell) hanging over the left optic nerve. Endoscopic sinus surgery was performed. The optic canal was extruding into the Onodi cell cavity, and the superior bony wall of the canal was eroded by the mucocele. The isolated mucocele in the Onodi cell seemed to be compressing the optic nerve downward and causing retrobulbar optic neuropathy. An Onodi cell lesion, even if it was isolated and small, would cause optic neuropathy. MRI and coronal CT scanning should be performed for the diagnosis and preoperative planning in a case of retrobulbar optic neuropathy.

A case of cerebellar infarction occurred with the 8th cranial nerve symptoms.

A rare case, 32-year-old man, of cerebellar infarction with the occurrence of the 8th cranial nerve symptoms was reported. On the neuro-otological examination, hearing test and caloric test showed a severe hearing loss and no response on the right side, respectively, and the spontaneous horizontal nystagmus fixed to the left direction was observed. Magnetic resonance (MR) imaging showed the infarctions in the areas of anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA) on the right side. On the 14th illness day, the 8th cranial nerve symptoms disappeared, and on the 12th illness day, right hearing level and caloric response were significantly improved. We suggested that such an early recovery of the subjective symptoms and neuro-otological findings may be attributable to the recanalized circulation disturbance or the development of collateral circulation.

Mucoepidermoid Carcinoma of the Vocal Cord

A case of mucoepidermoid carcinoma of the vocal cord is described in a 51-year-old man who presented with a thickened right vocal cord at the midportion without any limitation of movement. Histological examination revealed a mucoepidermoid carcinoma of low-grade malignancy. Partial laryngectomy was performed, but 10 months after the operation a squamous cell carcinoma developed on the other vocal cord. Primary vocal cord involvement of this tumor is rare. The literature is reviewed.

Cell Culture Study of the Vestibular Ganglion Cells: Morphology and Immunohistochemical Activity

Incubation of vestibular ganglion cells from the rat fetus and chick embryos was successfully done demonstrating bipolar cells and two types of multipolar cells, small round cells and large cells, in the cell cultures produced. Vestibular ganglion cells were found to be highly irregular in size. Furthermore, the presence of neurotransmitters (choline acetyl-transferase and substance P) was confirmed immunohistochemically. Substance P positive cells had many bipolar cells and some multipolar cells. However, choline acetyl transferase positive cells had some small multipolar cells but few bipolar cells. These findings suggest that all vestibular ganglion cells do not have the same function.

The Findings of Magnetic Resonance Imaging in Thyroid Masses.

We studied the findings of magnetic resonance imaging in thyroid masses. The study subjects included 44 cases of thyroid disease (16 of follicular adenoma, 16 of adenomatous goiter, 10 of papillary carcinoma, and 2 of follicular carcinoma). We compared 5 variables (irregularity of margin, heterogeneity of tumor, invasion to out of thyroid gland, pseudocapsule, and enhancement effect). The findings suggest that identifying irregularity of margin is the most useful finding in diagnosing a thyroid tumor as malignant.

Comparative Study of Cerebrospinal Fluid and Serological Data from Patients with Vestibular Neuronitis and Herpes Zoster

1) 前庭神経炎7症例全例に経過中, 髄液の総蛋白量の軽度増加を認め, 経過と共に増加する傾向がみられた. 細胞数の増加は認めなかった.2) 前庭神経炎全例の CSF/serum albumin index 及び IgG index は正常範囲であり, 特定な変動は認めなかった.3) 前庭神経炎症例で髄液中にHSV IgG (FA) かEB・VCA IgG (FA) のいずれかの抗体価を認めた例が5例存在した.4) 前庭神経炎症例でHSV IgG (FA) とEB・VCA IgG (FA) の髄液と血清の抗体価の比はそれぞれ1:160と≦1:80であった.5) 帯状疱疹例では急性期に測定し得た例についていずれも髄液の総蛋白の軽度増加を認め, 経過につれて正常化する傾向がみられた. 2例に髄液の細胞数の増加を認めた.6) 帯状疱疹症例の CSF/serum albumin index は全例正常範囲であったが, IgG index は, 細胞数の増加を認めた2例において上昇を認めた.7) 帯状疱疹症例の髄液中のVZV IgG (FA) の抗体価は, 細胞数の増加のみられた2例において認め, 血清との同抗体価の比は1:40～80であった.8) 帯状疱疹症例で髄液中にHSV IgG (FA) かEBV IgG (FA) のいずれかの抗体価を認めたものは4例で, 血清との同抗体価の比は, それぞれ1:160と1:320であった.