Hemostatic Thrombin-Gelatin Matrix-Related Intracranial Cyst Formation.

BACKGROUND: Local hemostatic agents have been used in the neurosurgical field for many years; it is safe and efficient with no fatal complication reported in the literature. We routinely used a gelatin-thrombin hemostatic agent (FloSeal Hemostatic Matrix) for hemostasis in minimally invasive endoscopic-assisted surgery for more than 500 patients with intracerebral hemorrhage. However, 2 cases with sterile cyst formation were encountered. CASE DESCRIPTION: We reported 2 cases with sterile cyst formation after the use of a gelatin-thrombin hemostatic agent. Both of them had intracerebral hemorrhage. One received endoscopic hematoma evacuation, and the other had traditional craniotomy. They all received drainage of the cyst due to progressive enlargement and the mass effect they exert. CONCLUSIONS: These sterile cysts were very close to the ventricle wall on images. We hypothesized that cyst wall may be formed not only by hemostatic agent-related fibrosis and inflammation according to the previous literature review but also by the presence of the check valve mechanism between the cyst and the ventricle, which caused further dilation of the cyst.

Estimation of the Craniectomy Surface Area by Using Postoperative Images.

Decompressive craniectomy (DC) is a neurosurgical procedure performed to relieve the intracranial pressure engendered by brain swelling. However, no easy and accurate method exists for determining the craniectomy surface area. In this study, we implemented and compared three methods of estimating the craniectomy surface area for evaluating the decompressive effort. We collected 118 sets of preoperative and postoperative brain computed tomography images from patients who underwent craniectomy procedures between April 2009 and April 2011. The surface area associated with each craniectomy was estimated using the marching cube and quasi-Monte Carlo methods. The surface area was also estimated using a simple AC method, in which the area is calculated by multiplying the craniectomy length (A) by its height (C). The estimated surface area ranged from 9.46 to 205.32 cm2, with a median of 134.80 cm2. The root-mean-square deviation (RMSD) between the marching cube and quasi-Monte Carlo methods was 7.53 cm2. Furthermore, the RMSD was 14.45 cm2 between the marching cube and AC methods and 12.70 cm2 between the quasi-Monte Carlo and AC methods. Paired t-tests indicated no statistically significant difference between these methods. The marching cube and quasi-Monte Carlo methods yield similar results. The results calculated using the AC method are also clinically acceptable for estimating the DC surface area. Our results can facilitate additional studies on the association of decompressive effort with the effect of craniectomy.