Pediatric vestibular schwannoma without evidence of neurofibromatosis: consecutive 18 microsurgical experiences.

PURPOSE: Sporadic vestibular schwannoma (VS) is rare in children in contrast to adults, and detailed investigations of case series of these patients using a single fixed protocol are scarce. This study presents our surgical experience of pediatric VSs without clinical evidence of neurofibromatosis type 2 (NF2) at the initial diagnosis. METHODS: Among 1385 consecutive sporadic VS surgeries, 18 pediatric patients (1.3%; 11-18 years old) were retrospectively investigated. RESULTS: The most common initial symptom was hearing disturbance (72.2%), and 6 patients (33.3%) experienced a delayed diagnosis (over 2 years after initial symptom onset). Preoperative image characteristics of these tumors included a solid tumor, hypervascularity, and significant extension into the internal acoustic meatus, when compared with adults. Preoperative embolization was successfully accomplished for 2 recent hypervascular tumors. The tumor resection rate was 95-100% under sufficient intraoperative neuromonitoring, and no additional surgery was required during the follow-up period (average: 57.9 months). No patients experienced permanent facial nerve palsy, and serviceable hearing function was preserved in 6 of 11 patients. Signs of NF2, such as bilateral VSs, were not identified in any patients during the follow-up. CONCLUSION: Safe and sufficient tumor resection was achieved under detailed neuromonitoring in pediatric patients with sporadic VS, although this tends to be difficult owing to hypervascularity, a small cranium, and significant meatal extension. Preoperative embolization may help safe resection of hypervascular tumors. Subsequent development of NF2 has not been observed up to the most recent follow-up, but careful observation is essential for these younger patients.

Management of Sigmoid Sinus Injury: Retrospective Study of 450 Consecutive Surgeries in the Cerebellopontine Angle and Intrapetrous Region.

BACKGROUND: The sigmoid sinus is the biggest obstacle when approaching the posterior fossa and temporal bone. Adequate sinus exposure is required to obtain a sufficient operative field, but sinus injury is a potentially life-threatening complication. OBJECTIVE: To present our experience of sigmoid sinus injury and its management during surgeries in the cerebellopontine angle and intrapetrous region, with operative videos. METHODS: A total of 450 consecutive surgeries (385 retrosigmoid and 65 transmastoid approaches) over a 4-yr period were retrospectively investigated, focusing on sigmoid sinus injury, its repair technique, and long-term patency of the sinus. RESULTS: Pinhole-sized bleedings were controlled sufficiently by bipolar coagulation or fibrin glue-soaked hemostatic fabric. For lacerations of smaller than 3 mm, the sinus wall was reconstructed by suturing. For larger or unsuturable holes, patching a Gore-Tex membrane on a fibrin glue sheet (without any suturing) was used for the reconstruction. Hemostatic agents were not used for large lacerations to avoid any potential risks of delayed sinus occlusion. Major sinus injury requiring suturing or Gore-Tex patching occurred in 13 cases (2.9%). The bleeding was immediately controlled without sinus clamping, and surgery was not discontinued owing to the injury in any of them. The patients had no postoperative symptoms associated with sinus injury. In all the reconstructed sinuses, patency was confirmed on magnetic resonance imaging at the final follow-up. CONCLUSION: Sigmoid sinus injury can be well managed with long-term patency by utilizing different repair techniques. Initial safe and adequate exposure around the injury site was essential for all of these repair procedures.