Total removal of cavernous hemangioma using the tonsillouveal transaqueductal approach (method)

Recent advances in microsurgical techniques facilitate surgical resection of brainstem lesions that were previously considered inoperable. Cavernous hemangiomas with repeated hemorrhage that reach the pial surface or display progressive neurological deficits can be resected safely with acceptable morbidity. Various approaches to the mesencephalon or midbrain, tailored to the exact location of the lesion, have been described. In this chapter we describe a novel approach to the mesencephalic tegmentum via the aqueduct, adding to contemporary microneurosurgery, respecting functional anatomy and minimizing neurological deficits.</p

Immediate results of microsurgical clipping of posterior communicating artery aneurysms using the pretemporal transclinoidal approach

Background: We evaluated adverse ischemic events as early surgical results of microsurgical clipping of 44 and 34 posterior communicating artery (PComA) aneurysms through the pterional transsylvian and pretemporal transclinoidal approach, respectively, between January 2007 and October 2010. Methods: Patients undergoing PComA aneurysm clipping were divided into two groups, and their immediate surgical results were compared and analyzed. Those who underwent the pterional transsylvian approach (group A) comprised 42 patients with 44 PComA aneurysms (24 ruptured and 20 unruptured). Those who underwent the pretemporal transclinoidal approach (group B) comprised 32 patients with 34 PComA aneurysms (20 ruptured and 14 unruptured). Results: The immediate postoperative total occlusion rates were 97.7% in group A and 100% in group B. The pretemporal transclinoidal approach significantly reduced the overall risk of silent and symptomatic ischemic strokes (p = 0.04) in ruptured PComA clippings and tended to lower the incidence of intraoperative aneurysm rupture (p = 0.07) as well as the overall ischemic events (p = 0.06) in a total of 78 aneurysm clippings, as compared with the pterional transsylvian approach. Although not significantly, the pretemporal transclinoidal approach also tended to have a lower incidence of intraoperative aneurysm rupture in ruptured aneurysm clippings (p = 0.11), which were mainly responsible for the symptomatic ischemia. The pretemporal transclinoidal approach had no additional advantage over the traditional pterional transsylvian approach in unruptured PComA aneurysm clippings in the present study. Conclusion: The pretemporal transclinoidal approach achieved better visualization of the vital neurovascular structures surrounding PComA aneurysms, which might be a key improvement in lowering the risk of intraoperative aneurysm rupture and obtaining significantly satisfactory immediate surgical results in the microsurgical clipping of PComA aneurysms, especially ruptured ones

Growth of unruptured aneurysms: A meta-analysis of natural history and endovascular studies

The growth of unruptured intracranial aneurysms (UIAs) is a strong predictor of rupture. Clinical observations suggest that some UIAs might grow faster after endovascular treatment than untreated UIAs. There are no head-to-head comparisons of incidence rates of UIAs thus far. Methods: We searched PubMed, Embase and Google Scholar for relevant articles from the inception of the databases to March 2020. We pooled and compared the incidence rates for the growth of aneurysms from natural history studies and endovascular treatment studies. Generalized linear models were used for confounder adjustment for the prespecified confounders age, size and location. Results: Twenty-five studies (10 describing growth in natural history and 15 reporting growth after endovascular therapy) considering 6325 aneurysms were included in the meta-analysis. The median size of aneurysms was 3.7 mm in the natural history studies and 6.4 mm in endovascular treatment studies (p = 0.001). The pooled incidence rate (IR) of growth was significantly higher in endovascular treatment studies (IR 52 per 1000 person-years, with a 95% confidence interval (CI) 36–79) compared to natural history studies (IR 28 per 1000 person-years, 95% CI 17 – 46, p-value < 0.01) after adjustment for confounders. Conclusion: Our results suggest that the incidence rate of cerebral aneurysm growth might be higher after endovascular therapy than the incidence rates reported in natural history studies. These results should be viewed in light of the risk of bias of the individual studies and the risk of ecological bias