Polytome-pantopaque: a technique for the diagnosis of small acoustic tumors. Technical note

The history of neurosurgery at the House Clinic in Los Angeles

Although most widely known as the birthplace of neuro-otology, the House Clinic in Los Angeles has been the site of several major contributions to the field of neurosurgery. From the beginning of the formation of the Otologic Medical Group in 1958 (later renamed the House Ear Clinic), these contributions have been largely due to the innovative and collaborative work of neurosurgeon William E. Hitselberger, MD, and neuro-otologist William F. House, MD, DDS. Together they were responsible for the development and widespread adoption of the team approach to skull-base surgery. Specific neurosurgical advances accomplished at the House Clinic have included the first application of the operative microscope to neurosurgery, the application of middle fossa and translabyrinthine approaches for vestibular schwannoma, and the development of combined petrosal, retrolabyrinthine, and other alternative petrosal approaches and of hearing preservation surgery for vestibular schwannoma. The auditory brainstem implant, invented at the House Clinic in 1979, was the first ever successful application of central nervous system neuromodulation for restoration of function. Technological innovations at the House Clinic have also advanced neurosurgery. These include the first video transmission of microsurgery, the first suction irrigator, the first debulking instrument for tumors, and the House-Urban retractor for middle fossa surgery.

The Management and Imaging of Vestibular Schwannomas

Vestibular schwannomas are the most common cerebellopontine angle tumor. During the past century, the management goals of vestibular schwannomas have shifted from total resection to functional preservation. Current treatment options include surgical resection, stereotactic radiosurgery, and observation. Imaging has become a crucial part of the initial screening, evaluation, and follow-up assessment of vestibular schwannomas. Recognizing and understanding the management objectives, various treatment modalities, expected posttreatment findings, and complications allows the radiologist to play an essential role in a multidisciplinary team by providing key findings relevant to treatment planning and outcome assessment. The authors provide a comprehensive discussion of the surgical management, role of radiation therapy and observation, imaging differential, and pre- and posttreatment imaging findings of vestibular schwannomas.

Intra and extracranial meningiomas involving the temporal bone

Meningiomas involving the temporal bone are very rare. Until 1964, only 39 cases had been reported in the world literature. Most series reported are very small and a physician is unable, based on his own experience, to acquire a sufficient knowledge about this entity and may raise serious doubts regarding the diagnosis and management of these tumors. In the past nine years the author has encountered five cases of meningiomas involving the temporal bone. This became a stimulus for a thorough research of the world literature of meningiomas in general, with emphasis on temporal bone involvement. Nine more cases were collected from cooperative physicians with whom the author has been associated. These 14 cases are the clinical material analysed in this study. This thesis is divided into three sections: 1. Exhaustive review of the world literature on meningiomas with emphasis on involvement of the temporal bone. 2. A detailed presentation and discussion of the clinical material stressing the importance of the newer diagnostic methods available and the most modern microsurgical techniques used in otological and neurological surgery procedures, applied to the treatment of those lesions. A light microscopic histopathological study of all cases reported is presented. Electronmicroscopy demonstrates the true intracellular nature of an atypical, recurrent meningioma occurring in a child. 3. A critical evaluation of the cases presented and the value of the diagnostic and therapeutic methods applied in this series of patients are here analysed. Conclusions are then drawn based on the experience and knowledge accumulated in this study. The histopathological diagnosis of meningiomas sometimes is difficult. Probably those tumors involve the temporal bone more commonly than has been reported in the literature. Some of these lesions probably are being misdiagnosed as chemodectomas or other neoplasias. Computerized axial tomography, particularly applied to the diagnosis of brain lesions, is the major break-through of recent modern medicine. A noninvasive technique, when used with contrast enhancement, offers great diagnostic possibilities. Early diagnosis of meningiomas and their complete surgical excision are the key factors necessary for a successful result with a good prognosis and a low recurrence rate. Although these tumors are classically considered radioresistant, radiotherapy may play a role in the treatment of incompletely excised lesions or in patients of a poor surgical risk. Further experiences and time will probably lead to more definite conclusions regarding the role of radiation therapy or the combined surgical and postoperative radiation treatment. Of all brain tumors, meningiomas offer the best prognosis.

Unilateral dilatation of the internal auditory canal

An unusual and functionally insignificant variant of the internal auditory canal is presented. Marked dilatation of one canal was demonstrated by petrous bone tomography. Pantopaque cisternography revealed a large intracanalicular extension of the subarachnoid space with no evidence of tumor. No patients should undergo exploration of this region without prior Pantopaque studies.

Iophendylate cisternography in diagnosis of cerebellopontine angle tumors. Report of 60 cases

60 cases of bilateral cerebellopontine angle pantopaque cisternography done between May, 1972, and April, 1974, are reported. Of these, 9 showed a unilateral acoustic neurinoma of different sizes, 1 showed a bilateral acoustic neurinoma all confirmed by operation. Technical details and advantages of the procedure are discussed. There were no complications related to the procedure.

Cerebellopontine angle myelography

✓ Review of more than 1400 positive-contrast myelograms of the posterior fossa performed at the Mayo Clinic indicates that this is an excellent method for depicting normal and pathological anatomy in the basal cisterns, if an adequate amount of medium and a precise technique are used. However, the technique is not without its sources of diagnostic error and these are discussed.

Suboccipital transmeatal microneurosurgical resection of acoustic tumors

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