Effects of Cerebral Ischemia on Levels of Vascular Endothelial Growth Factor (VEGF) and Its Soluble Receptors: A Possible Link to Angiogenesis in Arteriovenous Malformations.

AIM: To investigate the levels of vascular endothelial growth factor (VEGF) in the brain, and its soluble forms, namely sVEGFR1 and sVEGFR2, levels in the plasma of rats after cerebral ischemia. MATERIAL AND METHODS: Rats were divided into three groups as follows: Group 1: Sham-operated group, Group 2: Complete occlusion of the right carotid artery, Group 3: Complete occlusion of the right carotid artery and temporary occlusion of the left carotid artery for 10 min. Blood samples were collected on days 0 and 10 prior to the sacrification to measure the sVEGFR1 and sVEGFR2 levels. On day 10, animals were sacrificed, and brain tissue was collected to analyze VEGF expression. RESULTS: Postoperative sVEGFR1 levels reduced significantly in Group 3, while it remained stable in other groups. sVEGFR2 levels did not change in any group. Although VEGF staining scores in the groups that underwent ischemia procedures increased compared to group 1, no significant differences were observed. CONCLUSION: Decreased levels of sVEGFR1 can be a mechanism contributing to angiogenesis in arteriovenous malformations by increasing the levels of VEGF available to bind membrane-bound VEGFRs.

Comparison of TachoComb and TissuDura in Terms of Adverse Effects and Complications in Duraplasty in Rats.

AIM: To compare two synthetic graft materials, TachoComb®, a fibrin sealant composed of collagen, fibrinogen, thrombin and aprotinin and TissuDura®, a collagen-based biomatrix. MATERIAL AND METHODS: Thirty Sprague?Dawley rats were randomly divided into three groups with 10 animals in each group. A dural defect was created on the left parietal bone of each animal, and the dural defect was repaired using either TachoComb® (TachoComb group) or TissuDura® (TissuDura group). Sham animals did not receive any dural graft. After 21 days of follow-up, the brain was dissected, and inflammation, oedema, gliosis and foreign body reaction in the bone and parenchymal tissue were investigated histopathologically. RESULTS: The TachoComb group showed significantly greater inflammation, gliosis and parenchymal foreign body reaction compared with the sham group. By contrast, the TissuDura group had significantly lower gliosis and insignificantly less inflammation in the bone and parenchymal foreign body reaction compared with the TachoComb group. CONCLUSION: In conclusion, our results suggest that TissuDura® may be considered more biocompatible than TachoComb® in duraplasty.

Surgical Treatment of a Child With Acute Cortical Blindness Caused by Depressed Skull Fracture.

Linear skull fractures are relatively common in children, however, it is rarer to see depressed fractures. This report details the case of a 7-year-old boy who was admitted to the emergency department with complete blindness after having experienced an in-car traffic accident. Brain tomography of the patient showed that a large, island-shaped piece of occipital bone was depressed on the visual cortex and superior sagittal sinus in the midline. Presentation of complete loss of vision after an isolated head trauma is very rare, and there are no similar cases in existing literature. The limits of surgical indications for depressed skull fractures are well established in neurosurgical practice. Surgical intervention should be performed immediately, especially in cases where neurological changes develop in the earliest stages after a trauma. The patient underwent emergency surgery to correct the blindness without affecting the vascular neighborhood. The depressed cranium was raised to its original position. The blindness had completely resolved shortly after the patient woke up during the postoperative period.