ABSTRACT
BACKGROUND: The demand of a burr hole surgery for chronic subdural hematoma (CSDH) is increasing in the global aging society. Burr hole-derived autologous bone dusts are not associated with extra costs compared with other commonly used synthetic materials. In addition, postoperative calvarium ossification requires periosteum-mediated blood supply, which is lacking after using avascular synthetic materials. Based on these findings, we hypothesized that the combination of the bone plugs and the preserved periosteum during burr hole surgeries for CSDH would induce efficient calvarium ossification. METHODS: We evaluated the long-term effects of bone plugs on the degree of ossification and cosmetic appearance of the skin covering the burr hole sites. We included 8 patients (9 burr holes) who received the autologous bone dust derived from burr holes. As the control group, 9 burr holes that did not receive any burr hole plugs were retrospectively selected. These burr holes were evaluated by computed tomography (CT) scan for the calvarium defect ratios, CT value-based ossification, and the degree of skin sinking. RESULTS: Ossification was observed in all the bone plugs by the bone density CT scans; they maintained their volume at 12 months after the surgeries. The calvarium defect ratios (volume ratios of the unossified parts in the burr holes) gradually increased during the first 6 months and reached 0.44 at 12 months. The mean CT values also increased from 527 HU to 750 HU for the first 6 months and reached 905 HU at 12 months. The degrees of skin sinking at the burr hole sites with the bone plugs were 1.24 mm whereas those without the bone plugs were 2.69 mm (P = 0.004). CONCLUSION: Application of burr hole-derived autologous bone dust is associated with better ossification and objective cosmetic result following burr hole surgery after CSDH.
ABSTRACT
BACKGROUND: Sylvian dissection is an essential microneurosurgical skill for neurosurgeons. The safe and accurate opening of the sylvian fissure is desirable for a good prognosis. METHODS: The aim of this report is to demonstrate the use of indocyanine green (ICG) videoangiography to recognize the superficial sylvian vein (SSV) and thus enable a wide opening of the sylvian fissure, especially in patients with subarachnoid hemorrhage (SAH). RESULTS: The small tributary flowing into the SSV was distinguishable from a passing one, which deeply entered the insula. In addition, an entering point of a tributary to the SSV, which ran perpendicular to the insula, was occasionally determined. SSV, which was barely discernable in a reddish SAH involving the sylvian fissure, was clearly demarcated using ICG videoangiography. Two representative cases of sylvian dissection are herein presented. CONCLUSION: The performance of ICG videoangiography before sylvian dissection is a simple and useful method for identifying a vital approach route for safe and accurate sylvian dissection, and it reduces the risk of causing any accidental injury to the veins in the sylvian fissure.
