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Intracranial infection is one of the most common complications of open craniocerebral injury and of conventional craniotomy in neurosurgery. The presence of blood-brain barrier leads to lower drug concentrations in the cerebrospinal fluid than in the venous blood. Increasing the intravenous dosage or frequency carries the risk of systemic adverse reactions or infections in other parts of the body. Developing an artificial dura mater (ADM) for sustained antibiotic release for use during neurosurgery can solve the problems perfectly.Three types of drug-loaded ADMs made of collagen and containing cefuroxime sodium, ceftriaxone sodium, or norvancomycin were prepared. The antibacterial activity and sustained release characteristics of the ADMs were examined using bacteriostatic and release tests.Single-layered collagen based ADMs (40 mm×50 mm×5 mm) containing 18 mg cefuroxime sodium or ceftriaxone sodium were not suitable for continued development because of drug preservation and stability issues. Using smaller ADMs (20 mm×30 mm×7 mm), containing 4.86 mg of norvancomycin, with increased collagen density and a three-layered film with two outer drug-free films above and below the antibiotic layer resulted in sustained cumulative release of 2.91 mg (59.9%) of norvancomycin over 72 hours. The similar factor (f2) comparison method proved that products from a same batch were statistically significant similar (f250).Artificial ADMs made of collagen can be processed to provide a mature dural repair material for the sustained release of norvancomycin. This system may provide a basis for developing sustained release materials for other drugs.

Standard superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery is an effective treatment for moyamoya disease, but recent evidence suggests that postoperative cerebral hyperperfusion can occur. In this study, the trendline of changes in regional cerebral blood flow (rCBF) after surgery were continually monitored near the site of anastomosis in order to investigate both the efficacy of the procedure for improving rCBF and the possible risk of hyperperfusion.Standard STA-MCA bypass surgery was performed on 13 patients. rCBF was measured continually using laser Doppler flowmetry (LDF) until the 5th day after the operation with the LDF probe implanted adjacent to the area of the anastomosis. The trendline of rCBF changes postoperatively was recorded for the analysis performed using SPSS 13.0.The baseline LDF value of cortical rCBF was (84.68 + or - 14.39) perfusion unit (PU), which was linear relative to absolute perfusion volume before anastomosis and (88.90 + or - 11.26) PU immediately after anastomosis (P0.05). The value changed significantly from before to after anastomosis (P0.05); it was (417.72 + or - 21.35) PU on the 1st day after surgery, and (358.99 + or - 18.01) PU, (323.46 + or - 17.38) PU, (261.60 + or - 16.38) PU and (375.72 + or - 18.45) PU on the following 4 days, respectively. The rCBF decreased gradually from the 2nd day until the 4th postoperative day, but still was at a high level (P0.05). However, on the 5th postoperative day the rCBF increased again to the second highest level, which was significantly different compared with the baseline value (P0.05), but not significantly different compared with the values on the other 4 days (P0.05).STA-MCA anastomosis improves the cerebral blood supply significantly in the early stage after surgery, however, the risk of symptomatic hyperperfusion may exist, which may possibly occur on the 1st day and 5th day after surgery. A LDF is useful for postoperative monitoring for both the efficacy of bypass and possible risk of neurologic deterioration or bleeding from hyperperfusion.