ABSTRACT
BACKGROUND: Cystic vestibular schwannoma (CVS) traditionally considered as poor responder to gammaknife radiosurgery (GKRS). Their longterm radiobiological behavior is less known. Here we discuss 38 cases with intra tumoral cyst CVS primarily treated with GKRS. Tumor morphology was assessed to understand their response to GKRS. METHODS: Total 38 patients(21 male and 17 female with median age of 41.7 years) of CVS treated with GKRS were retrospectively analysed. Tumors were divided as predominantly (greater than50% of total tumor volume) cystic or solid. They were subclassified as type 1 (predominantly cystic CVS, single cyst), type 2 (predominantly solid CVS, single cysts), type 3 (multicystic CVS). The entire cyst was incorporated for radiosurgery. The results were compared with volume matched control of 58 solid tumors(SVS). RESULT: The median tumor volume of CVS was 5.8 cc. The median tumor volume reduction was 44.5 % at a median follow-up of 68.5 months (30-110 months). Median tumor volume reduction was 68.5 %, 34.0%, 11.0.%, 30.5% at a median follow up of 52.5months, 66 months, 78.6 months, 96.5 months for type 1 CVS, type 2 CVS, type 3 CVS and SVS respectively. One patient with multicystic CVS showed increased tumor volume and expired after 9 months of surgery.The tumor volume reduction in type 1CVS was statistically significant as compared to type 3 CVS and SVS. However the tumor volume reduction among other groups did not differ significantly. CONCLUSION: Intra tumoral cystic components respond better to gammaknife radiosurgery in CVS. Tumor with single cyst respond better than multicystic vestibular schwannoma.
Subject(s)
Cysts , Neuroma, Acoustic , Radiosurgery , Humans , Male , Female , Adult , Neuroma, Acoustic/diagnostic imaging , Neuroma, Acoustic/radiotherapy , Neuroma, Acoustic/surgery , Treatment Outcome , Radiosurgery/methods , Retrospective Studies , Cysts/surgery , Follow-Up StudiesABSTRACT
OBJECTIVES: Craniotomies/craniostomies have been categorized as aerosol-generating procedures and are presumed to spread coronavirus disease 2019 (COVID-19). However, the presence of severe acute respiratory distress syndrome coronavirus 2 virus in the generated bone dust has never been proved. Our objective is to evaluate the presence of virus in the bone dust (aerosol) generated during emergency neurosurgical procedures performed on patients with active COVID-19. This would determine the true risk of disease transmission during the surgery. METHODS: Ten patients with active COVID-19 infection admitted to our institute in 1 month required emergency craniotomy/craniostomy. The bone dust and mucosal scrapings form paranasal sinuses (if opened) collected during these procedures were tested for the virus using reverse transcription polymerase chain reaction. The entire surgical team was observed for any symptoms related to COVID-19 for 14 days following surgery. RESULTS: Nine patients had moderate viral load in their nasopharyngeal cavity, as detected on reverse transcription polymerase chain reaction. None of the samples of bone dust from these 10 patients tested positive. Mucosal scrapping obtained in 1 patient in which mastoid air cells were inadvertently opened tested negative as well. No health workers from the operating room developed COVID-19-related symptoms. CONCLUSIONS: The bone dust generated during craniotomy/stomy of active patients does not contain the virus. The procedure on an active patient is unlikely to spread the disease. However, a study with larger cohort would be confirmatory.