Neurosurgery

Kulkarni, Abhaya V.; Drake, James M.; Kestle, John R.W.; Mallucci, Conor L.; Sgouros, Spyros; Constantini, Shlomi; For the Canadian Pediatric Neurosurgery Study Group

Neurosurgery. 67(3):588-593, September 2010.

doi: 10.1227/01.NEU.0000373199.79462.21

BACKGROUND: Endoscopic third ventriculostomy (ETV) has more favorable prognostic features compared with shunt. OBJECTIVE: To determine whether ETV survival is superior to shunt survival. METHODS: An international cohort of children (≤ 19 years of age) with newly diagnosed hydrocephalus treated with ETV (n = 489) or shunt (n = 720) was analyzed. We used propensity score adjustment techniques to account for 2 important patient prognostic factors: age and cause of hydrocephalus. Cox regression survival analysis was performed to compare time-to-treatment failure in an unadjusted model and 3 propensity score—adjusted models, each of which would adjust for the imbalance in prognostic factors. RESULTS: In the unadjusted Cox model, the ETV failure rate was lower than the shunt failure rate from the immediate postoperative phase and became even more favorable with longer duration from surgery. Once patient prognostic factors were corrected for in the 3 adjusted models, however, the early failure rate for ETV was higher than that for shunt; about 3 months after surgery the ETV failure rate was lower than the shunt failure rate. CONCLUSIONS: The relative risk of ETV failure is initially higher than that for shunt, but after about 3 months, the relative risk becomes progressively lower for ETV.

Abstract:

Sameshima, Tetsuro; Fukushima, Takanori; McElveen, John T. Jr; Friedman, Allan H.

Neurosurgery. 67(3):640-645, September 2010.

doi: 10.1227/01.NEU.0000374853.97891.FB

BACKGROUND: The middle fossa (MF) or retrosigmoid (RS) approach can be used for hearing preservation in acoustic neuroma (AN) surgery. OBJECTIVE: To present our operative results in these 2 approaches. METHODS: We reviewed 504 consecutive AN resections performed between November 1998 and September 2007 and identified 43 MF and 82 RS approaches for tumors smaller than 1.5 cm. were examined hearing ability, facial nerve activity, operative time, blood loss, and symptoms resulting from retraction. RESULTS: Good hearing function (AAO-HNS class B or better) was preserved in 76.7% of patients with the MF approach and in 73.2% in the RS group (P = .9024). Temporary facial nerve weakness was more frequent in the MF group (P = .0249). However, late (8–12 months) examinations showed good recovery in both. The mean operative time was 7.45 hours for the MF group and 5.2 hours for the RS group (P = .0318). The mean blood loss was 280.5 mL for the MF group and 80.8 mL for the RS group (P < .0001). Temporary symptoms of temporal lobe edema (drowsiness or speech disturbance) were noted in 6 MF cases. No cerebellar dysfunction was noted in the RS group. CONCLUSIONS: Although hearing and facial nerve function assessed at approximately 1 year was similar with these 2 approaches, the RS approach provided several advantages over the MF approach for ANs smaller than 1.5 cm.

Abstract:

Sughrue, Michael E.; Shah, Jugal K.; Devin, Jessica K.; Kunwar, Sandeep; Blevins, Lewis S. Jr.

Neurosurgery. 67(3):688-695, September 2010.

doi: 10.1227/01.NEU.0000374722.50042.FF

BACKGROUND: Serial measurements of serum cortisol in the days following pituitary surgery are recommended to identify patients at risk of recurrence. OBJECTIVE: We systematically reviewed the literature and analyzed the usefulness of this measurement in our patient population. METHODS: We identified studies regarding recurrence rates after transsphenoidal surgery for Cushing's disease, focusing on studies with data of early postoperative cortisol levels. We determined a cumulative relative risk of a subnormal versus normal cortisol level postoperatively using a fixed-effects meta-analysis model. Additionally, we analyzed our patients with Cushing's disease undergoing transsphenoidal surgery and performed Kaplan-Meier analysis of recurrence-free survival for patients with undetectable, subnormal but detectable, and normal immediate 8 AM serum cortisol levels. RESULTS: Fourteen studies met inclusion criteria. The length of follow-up varied between 32 and 115 months. The cumulative rate of recurrence in the group of patients with subnormal cortisol levels was 9% (95% confidence interval: 6%–12%). The cumulative rate of recurrence in the group with normal cortisol levels was 24% (95% confidence interval: 17%–31%). We analyzed 73 of our patients and found similar recurrence rates in patients with subnormal versus normal early postoperative cortisol levels (4% vs 22%, χ2 test, P < .05). CONCLUSION: Although a subnormal early postoperative cortisol level is predictive of improved outcome after transsphenoidal surgery for Cushing's disease, it is not analogous with cure, nor is a normal level predictive of failure.

Abstract:

Schatlo, Bawarjan; Dreier, Jens P.; Gläsker, Sven; Fathi, Ali-Reza; Moncrief, Travis; Oldfield, Edward H.; Vortmeyer, Alexander O.; Pluta, Ryszard M.

Neurosurgery. 67(3):721-729, September 2010.

doi: 10.1227/01.NEU.0000378024.70848.8F

BACKGROUND: In autopsy studies, 70% to 80% of patients with aneurysmal subarachnoid hemorrhage (SAH) showed infarcts in cerebral cortex covered by subarachnoid blood. Thus far, no animal model of SAH produces this peculiar infarct pattern. OBJECTIVE: To investigate whether such infarcts occur in the clot model of SAH in primates. METHODS: A retrospective pathological review of 16 primate brains. In 13 cynomolgus monkeys, a blood clot was placed around the middle cerebral artery. Three animals underwent sham surgery without placement of a blood clot. The brains were examined by a neuropathologist blinded to study group between days 1 and 28 after SAH. RESULTS: We identified 2 types of cortical infarcts. A band of selective cortical laminar necrosis parallel to the cortical surface (“horizontal”) was found in 5 animals. The second category of cortical lesions had a “vertical” extension. It included wedge-shaped (n = 2) or pillarlike (n = 2) necrosis. Both horizontal and vertical infarcts were located exclusively in areas adjacent to subarachnoid blood. The presence of a cortical infarct did not correlate with the degree of middle cerebral artery vasospasm (r2 = .24, P = .13). CONCLUSION: A modified nonhuman primate model of SAH is suitable to examine the pathogenesis of proximal vasospasm and permits investigation of cortical lesions similar to those reported in patients after SAH. Furthermore, direct effects of the blood clot on the brain and microcirculation may contribute to the development of cortical infarcts.

Abstract:

de Almeida, João Paulo C.; Sherman, Jonathan H.; Salvatori, Roberto; Quiñones-Hinojosa, Alfredo

Neurosurgery. 67(3):770-780, September 2010.

doi: 10.1227/01.NEU.0000373013.75994.CD

BACKGROUND: Stem cell characteristics, including renewal, proliferation and markers, have been demonstrated in adult pituitary cells from mammals. However, the proliferation ability observed so far is limited, and the potential of differentiation into hormone-secreting cells remains to be conclusively proven. OBJECTIVE: We discuss which cells in the adult pituitary gland might play a role as pituitary stem cells, the potential for these cells to initiate pituitary adenomas, and possible future clinical implications. METHODS: We reviewed the English literature for articles related to stem cells in the adult pituitary, cells with embryonic profile in the adult gland, mitogenic characteristics of adult pituitary cells, and pituitary adenoma oncogenesis. RESULTS: We identified and analyzed 135 articles published since 1965. CONCLUSION: Better understanding of pituitary stem cells may lead to clinical applications for treatment of pituitary adenomas and the implantation of pituitary stem cells for hormonal deficiencies may be developed.

Abstract:

Natarajan, Sabareesh K.; Hauck, Erik F.; Hopkins, L. Nelson; Levy, Elad I.; Siddiqui, Adnan H.

Neurosurgery. 67(3):794-798, September 2010.

doi: 10.1227/01.NEU.0000374724.78276.A6

OBJECTIVE: To describe endovascular access for treatment of vasospasm of a radial artery bypass graft in a patient with moyamoya disease. CLINICAL PRESENTATION: A 32-year-old woman presented with recurrent right-sided ischemic symptoms. Angiographic findings were consistent with moyamoya disease. TECHNIQUE: The patient underwent a left MCA bypass graft. She returned with an occluded bypass graft, collateralization of the anterior MCA territory through a spontaneous synangiosis, and a severe perfusion deficit. She underwent a revision bypass graft procedure with the radial artery. She developed repeated symptomatic vasospasm of the radial artery graft. The graft was accessed through the occipital artery, and intra-arterial verapamil was injected. When this failed to resolve the graft spasm, the radial artery graft was accessed with a 0.14-inch Synchro-2 microwire (Boston Scientific, Natick Massachusetts), and sequential angioplasties were performed. RESULTS: No complications occurred. Graft patency with robust flow was observed on the 5-month follow-up angiogram. CONCLUSION: Endovascular techniques can be safely used for salvage of spastic extracranial-intracranial grafts.

Abstract:

Kulcsár, Zsolt; Wetzel, Stephan G.; Augsburger, Luca; Gruber, Andreas; Wanke, Isabel; Andre Rüfenacht, Daniel

Neurosurgery. 67(3):789-793, September 2010.

doi: 10.1227/01.NEU.0000372920.39101.55

BACKGROUND: Ruptured aneurysms of < 2 mm are not amenable to endovascular coiling. OBJECTIVE: To test recently introduced flow diverters that allow endovascular reconstruction as an alternate method to treat these aneurysms. PATIENTS AND METHODS: Three female patients presented with subarachnoid hemorrhage. An aneurysm of < 2 mm was identified as the cause of bleeding. The aneurysms were located at the C2 segment of the internal carotid in 2 patients and on the basilar bifurcation in the other. All patients had failed early endovascular treatment attempts. Flow diversion with the SILK flow diverter was offered as an alternative in each patient. RESULTS: SILK deployment successfully eliminated all the aneurysms. There was no treatment-related morbidity, and none of the aneurysms reruptured after SILK implantation during a clinical follow-up of at least 4 months (range, 4–10 months). Imaging follow-up showed complete vessel remodeling in all cases. CONCLUSION: Flow diversion treatment prevented rebleeding during the follow-up period.

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