Pneumosinus dilatans of the sphenoid and visual loss: when should the optic nerve be decompressed?

Pneumosinus dilatans of the sphenoid sinus is a rare disorder which can be responsible for visual impairment and blindness. We present the case of an adolescent female who experienced progressive decrease in right-eye vision over 2 years. CT scan of the head showed an extensive pneumatization of the sphenoid bone extending to the lesser wing of the sphenoid and to the anterior clinoid process on the right side. MRI revealed right nerve atrophy in the optic canal and in the posterior part of the orbit. A surgical decompression of the right optic canal was performed via an intradural fronto-pterional approach. Postoperatively, her vision worsened, and at 3 years the patient was able to count fingers at 2.5 m. Our case and literature review of symptomatic sphenoidal pneumosinus dilatans confirmed that visual prognosis in such cases depended on the preoperative visual status. Early surgical decompression should be proposed whenever possible, before signs of severe visual disorders and optic atrophy.

Functional sparing surgery policy for giant vestibular schwannomas.

OBJECTIVE: The objective of this study was to compare the tumour control and facial nerve outcome according to the therapeutic strategy, that is extent of resection and post-operative radiotherapy. DESIGN: Retrospective study of patients with a giant vestibular schwannoma surgically treated from 4 academic skull base centres. SETTING: Extent of resection, neurological complications, facial nerve function, MRI follow-up and occurrence of complementary treatment were reviewed. PARTICIPANTS: Sixty patients were included from 2000 to 2018. MAIN OUTCOME MEASURES: Primary end points were comparison the tumour control rate and the post-operative House-Brackmann grade at last follow-up according to the extent of tumour removal (ie total or subtotal removal). Secondary end points were assessment risk factors of poor facial nerve function and comparison complication rate according to extent of tumour removal. RESULTS: Sixty patients had initial surgery at diagnosis. A total resection was realised in 21 cases and a subtotal resection in 39 cases. Thirteen patients needed further treatment. One patient had a recurrence and needed a second surgery 108 months after the initial total resection surgery. Twelve patients underwent post-operative radiotherapy, for an evolutive residual tumour. Tumour control was more successful in the total resection group (log-rank test, P = .015). There was no tumour recurrence after post-operative radiotherapy. The facial nerve outcome was significantly better in the subtotal resection group (Mean House-Brackmann grade at last follow-up: 2.2 ± 1.9) than in the total resection group (House-Brackmann grade: 3.5 ± 2.2) (P = .033). Vestibular schwannoma with a cystic component had better facial nerve outcome (P = .0082). Other than facial paralysis, neurological complications were observed in six patients (10% of patients): lower cranial nerves dysfunction in five cases and hemiparesis in one case. CONCLUSIONS: Subtotal resection of giant vestibular schwannomas leads to favourable tumour control and facial nerve function and therefore seems to be a valuable strategy.

Ruptured intracranial arachnoid cysts in the subdural space: evaluation of subduro-peritoneal shunts in a pediatric population.

PURPOSE: Rupture of arachnoid cysts (AC) in the subdural space after trauma may cause a subacute/chronic subdural hematoma or a hygroma. Treatment of this complication still remains controversial, and no consensual strategy is to date clearly proposed. In this study, the authors evaluated the clinical and radiological evolution of patients treated by a subduro-peritoneal shunt for symptomatic subdural collections complicating ruptured AC. METHODS: Medical records of the 10 patients treated at our institution between January 2005 and December 2018 for a subdural collection associated with an intracranial AC were reviewed. Subduro-peritoneal shunts consisted of low-pressure valves from 2005 to 2012 (6 cases) and medium-pressure valves after 2012 (4 cases). RESULTS: A benign head trauma was retrospectively found in the history of 8 patients. The mean time to diagnosis ranged from 15 days to 5 months. Symptoms resulted mainly from intracranial hypertension. Six patients had an ipsilateral hygroma to the AC, 2 patients had a bilateral hygroma predominantly to the AC side, and 2 patients presented an ipsilateral chronic subdural hematoma. Arachnoid cysts were classified as Galassi I in 5 cases and Galassi II in 5 cases. Patients with chronic subdural hematoma were given a medium-pressure valve. Patients with subdural hygroma received a low-pressure valve in 6 cases and a medium-pressure valve in 2 cases. There were no complications during surgical procedures. All patients were rapidly free of symptoms after surgery and were discharged from hospital 1 to 4 days postoperatively. The subdural collection completely disappeared in all cases. In the long term, only 2 patients with low-pressure valves underwent shunt removal without any consequences, while a second surgical procedure was necessary to treat recurrence of intracranial hypertension in the 4 remaining cases. All the medium-pressure valves were removed without problems. The size of the AC was reduced in 3 cases, remained stable in 4 cases, and increased in 3 cases. No patients experienced recurrence of subdural collection during follow-up. CONCLUSIONS: Medium-pressure subduro-peritoneal shunts should be considered as part of the arsenal of surgical strategy in symptomatic ruptured AC in the subdural space. The procedure is simple with a very low morbidity, and it allows rapid improvement of symptoms. Although the shunt is located in the subdural space, we strongly recommend avoiding devices which may create an overdrainage and expose the patient to shunt dependency such as low-pressure shunts.