ICAR: endoscopic skull‐base surgery

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Diagnóstico e localização de tumores intracranianos mediante mapeamento com mercúrio radioativo (Hg203)

Os autores discutem sua experiência com o emprêgo de mercúrio radioativo para o mapeamento de tumores e granulomas intracranianos, concluindo que êste método é atualmente o melhor para demonstrar e localizar lesões expansivas intracranianas, pois seu valor foi demonstrado em 83,1% dos casos. Entretanto nem todos os tumores são demonstráveis por êste método: os glioblastomas e meningeomas forneceram mapas de valor diagnóstico na maioria dos casos; os astrocitomas podem passar despercebidos: os epidermóides não foram demonstrados. Os tumores da base do crânio e os da fossa posterior podem ser mascarados pela alta apacidade dos músculos do pescoço e das mucosas dos seios paranasai m absorver a substância radioativa. O método é segúro, de aplicação econômica e não causa desconfôrto ao doente. Êle não deve ser usado por médicos que não estejam orientados no sentido neurológico para o diagnóstico de tumores intracranianos. Infelizmente os tumores que não são evidenciados por êste método são de caráter relativamente benigno e, portanto, os mais suscetíveis de tratamento cirúrgico

Intrasellar schwannomas: Report of two cases

OBJECTIVE AND IMPORTANCE: The complex regional anatomic features surrounding the sella turcica make the differential diagnosis of intrasellar and parasellar lesions complicated. Sellar and parasellar schwannomas are rare. With the exclusion of parasellar schwannomas arising from cranial nerves within the cavernous sinus and extending into the sella, there have been only two reported cases of true intrasellar schwannomas. CLINICAL PRESENTATION: We describe the clinical, radiological, and pathological features of two cases in which the histopathological diagnosis of schwannoma was confirmed with immunohistochemical analyses and/or electron microscopy. INTERVENTION: The two cases were grossly resected via a transsphenoidal approach. Follow-up monitoring revealed no evidence of recurrence. CONCLUSION: Schwannomas may atypically occur in the sellar region, in which they demonstrate the typical light microscopic, immunohistochemical, and ultrastructural features observed in the peripheral nervous system. New and existing hypotheses regarding the histopathogenesis of intrasellar and parasellar schwannomas are presented

Use of FloSeal hemostatic sealant in transsphenoidal pituitary surgery: Technical note

OBJECTIVE: Bleeding during transsphenoidal pituitary surgery can lead to a variety of operative difficulties. When the endonasal transsphenoidal approach is used, even mild intraoperative hemorrhage can lessen visibility in the confined operative field of view. This technical note describes the use of a hemostatic agent we have found of benefit in obtaining prompt hemostasis during this operation. METHODS: Operative records were reviewed for an 18-month period for all patients who underwent transsphenoidal surgery since we began using FloSeal hemostatic sealant in January 2000. RESULTS: During the study period, 293 transsphenoidal operations were performed for pituitary lesions. Of these, 20 procedures involved vigorous or persistent bleeding. When the standard techniques for hemostasis failed or were inadequate, FloSeal, a sterile mixture of a gelatin matrix and thrombin component mixed at the time of use, was applied to the site of hemorrhage by use of a 14-gauge angiocatheter to reach the sella. We observed complete hemostasis immediately on application of FloSeal in all cases except one, which required a second application. Hemostasis was obtained immediately after the second application. No operations were aborted during this period as a consequence of undue bleeding. CONCLUSION: We detail the method in which we use FloSeal in transsphenoidal surgery and report our impression of its effectiveness. FloSeal has been demonstrated to be safe and biocompatible as compared with hemostatic agents currently in use