Speakers

APPROACHES TO VENTRAL BRAIN STEM LESIONS
1108 14:30-14:40
Neuro-oncology/305
Background: Technological advancements have made brain stem lesions operable. However, the majority of lesions operated are exophytic, dorsal and close to a pial surface. Ventral lesions have been thought to be “non-operable” as results were often poor. The use of technology and the better understanding of anatomy has made these ventral lesions approachable and operable with good results. Methods: A retrospective study was done of the brain stem lesions operated over the last 20 years. The ventral lesions were then studied for location, approach used, outcome and pathology. Results: 145 patients with brain stem lesions were operated between 2003 and 2023.Forty eight were ventrally located. The lesions were Thalamo-peduncular or Midbrain in 13, Pontine in 30 and Medullary in 5. The approaches used were Antero-lateral basal for Midbrain lesions. A Para-oculomotor entry was used to access the lesions. Pontine lesions were approached using retrosigmoid approach and a para-trigeminal entry. The medullary lesions were accessed using a far lateral infratonsillar approach and a para-olivary entry. Navigation and intra-operative monitoring were used in majority of cases. The pathologies encountered were Gliomas (28/48) and cavernomas (16/48) with other pathologies seen rarely. Maximal safe resection was done in the gliomas while a radical excision was performed in the cavernomas. There was transient worsening of neurology in 5/21 gliomas, with new cranial nerve deficits in 4 patients. Most patients improved in their neurology at discharge. Conclusion A Ventral location of a brain stem lesion does not preclude surgical excision. Classical approaches with modifications suitable for the individual case allows access to the lesions. The combination of advanced neuroimaging and intraoperative adjuncts along with good microsurgical techniques helps deliver good results.

MICROVASCULAR DECOMPRESSION FOR TINNITUS - A RAY OF HOPE
1108 16:55-17:05
Skull Base/304A
Background Janetta popularized Microvascular decompression (MVD) surgery not only for Trigeminal neuralgia but also extended the concept to other cranial nerves including the vestibulo-cochlear nerve. Tinnitus is a relatively common clinical complaint and most often is related to a problem in the middle ear. However MVD for tinnitus has not gained popularity due to the variable results seen post-surgery. Materials and Methods A retrospective study was carried out of patients undergoing MVD surgery for Tinnitus and operated on by the author between 2021 and 2023. All patients underwent a detailed ENT and audiological evaluation, psychological evaluation, Tinnitus Handicap Scoring (THI), and had some form of treatment for the tinnitus before they were offered MVD surgery. Outcomes were based on the patients’ response to level of residual disability due to the tinnitus and were grouped as Poor (disability more than 80%), Fair (disability 30%-80%) and good (disability less than 30%). Results: A total of 21 patients underwent 26 MVD procedures, with 5 patients undergoing bilateral surgery. Tinnitus was the primary symptom for which surgery was done. Associated symptoms included hearing loss in patients and Vertigo in . None of the patients had HFS. The age range was 28 years to 69 years with a mean of 36.8 years. A majority of patients were in the 4th decade and were male. The mean THI was 88.9 (range 45-100). The tinnitus was bilateral in 7 patients, on the left in 8 patients and 6 on the right side. An Endoscope assisted Microvascular decompression was performed in all cases. Follow up of patients showed a good outcome in 5, 11 and 19 of 21 patients at 14 days, 3 months and 12 months respectively. A poor outcome (with a Tinnitus disability of more than 80%) was seen in 8 patients at 14 days and 1 of 21 patients at 12 months. There was no increase in hearing disability nor any facial weakness seen post-operatively. Wound problems including Pseudomenngocele and superficial SSI were seen in 5 and 2 patients respectively. Conclusions: Microvascular decompression surgery can be performed safely and achieves good outcomes in a majority of patients with tinnitus. Patient selection is very important and should be done in a protocolized manner. The surgery provides relief and an improved quality of life to patients suffering from an extremely disabling problem.