Posterior Cerebral Artery-to-Superior Cerebellar Artery Side-to-Side Bypass via Extreme Lateral Supracerebellar Infratentorial Approach: Technical Note

BACKGROUND

Difficult-to-treat aneurysms of the distal posterior cerebral artery (PCA) can often be treated by parent artery occlusion. A cerebrovascular bypass can complement PCA occlusion to curb the risk of ischemic complications. An in situ bypass may be considered when the occipital artery or superficial temporal artery cannot serve as a bypass donor. This article describes the use of a side-to-side bypass of superior cerebellar artery as a donor to the PCA via an extreme lateral supracerebellar infratentorial approach (ELSCIT). This bypass approach can be a useful surgical strategy for PCA revascularization.

METHODS

A 40-year-old woman underwent a side-to-side PCA-superior cerebellar artery bypass via the ELSCIT approach for to treat a complex and previously coiled PCA aneurysm. The bypass was followed by endovascular aneurysm and parent artery occlusion.

RESULTS

Postoperatively, the patient experienced transient, partial trochlear nerve palsy of the left eye without ischemic lesions on magnetic resonance imaging. The clinical condition was stable, and angiography showed a patent bypass and complete aneurysm occlusion 12 months after surgery.

CONCLUSIONS

The ELSCIT approach offers access to the medial and distal PCA that is suitable for a side-to-side PCA-superior cerebellar artery bypass. This type of approach and bypass may be of value when revascularization of a P2-P3 portion of the PCA is needed, but a suitable occipital artery or superficial temporal artery is not available.

Efficacy and histopathological effects of self-assembling peptides RADA16 and IEIK13 in neurosurgical hemostasis

There is a continued need for effective hemostatic agents that are safe for neurosurgical use. Self-assembling peptide hydrogels have been suggested as novel hemostatic agents. They offer some advantages for neurosurgical hemostasis (e.g., transparency), but their efficacy and safety for neurosurgery has not been established. In this paper, the efficacy and safety of two self-assembling peptides, RADA16 and IEIK13, are explored for hemostasis of oozing bleeding on the rat cerebral cortex (n=56). Chronic safety was evaluated by neuropathological evaluation at one, four, and twelve weeks after craniotomy (n=32). An inactive control and oxidized cellulose served as comparators. Mean time-to-hemostasis was significantly shorter for RADA16 and IEIK13 compared to controls, while safety evaluation yielded similar results. Histopathological response consisted primarily of macrophage infiltration at the lesion site in all groups. This study confirms the hemostatic potential and safety of RADA16 and IEIK13 for hemostasis in the rat brain.

Polyvinyl Alcohol Sponges to Facilitate Cerebral Bypass Surgery: Technical Note

OBJECTIVE

The standard way of isolating bypass vessels from surrounding structures during cerebral bypass surgery has been to use a rubber dam or neurosurgical patty. Here, the use of polyvinyl alcohol (PVA) sponges is described as a possible upgrade from these traditional bypass dams.

METHODS

PVA sponges were used to isolate bypass arteries from surrounding tissues during microvascular anastomosis in 25 patients undergoing bypass surgery at our institution.

RESULTS

There were no adverse events related to the use of PVA for microvascular anastomosis. PVA sponges offered some specific advantages when compared with rubber and cottonoid dams.

CONCLUSIONS

Although preliminary, our experience using PVA sponges during microvascular anastomosis suggests some of their properties can facilitate cerebral bypass surgery.

Extreme Lateral Supracerebellar Infratentorial Approach (ELSCIT) for Occipital Artery-to-Posterior Cerebral Artery Bypass: Results in 3 Cases

OBJECTIVE/BACKGROUND

The need for revascularization of the distal posterior cerebral artery (PCA) in the treatment of PCA aneurysms is a contentious issue. Approaches to the PCA, such as the subtemporal route, carry significant perioperative risk. This risk at times outweighs the risk of ischemia associated with endovascular PCA sacrifice. This paper describes the use of an extreme lateral supracerebellar infratentorial (ELSCIT) approach as an alternative technique for distal PCA revascularization.

METHODS

Between 2016 and 2019, 3 patients underwent a PCA bypass via the ELSCIT approach for the treatment of a PCA aneurysm. In all cases, an end-to-side anastomosis to the P2- or P3-segment of the PCA was made, with the occipital artery as a donor. Bypass procedures were followed by endovascular parent artery occlusion, without ischemic complications.

RESULTS

In all 3 cases, the ELSCIT approach offered a broad enough surgical corridor to perform an occipital artery-to-PCA bypass. One patient suffered a cerebrospinal fluid leak that was surgically treated. Patients' clinical conditions were stable on follow-up (mean follow-up of 34 months). All 3 aneurysms remained occluded, and no ischemia was detected on magnetic resonance imaging.

CONCLUSIONS

The ELSCIT approach offers an alternative route to the distal PCA for extracranial-to-intracranial bypass with seemingly low perioperative morbidity and good surgical access to the PCA.

Ruptured blood blister like aneurysm: does the best therapeutic option really exist?

Our study aimed to evaluate the outcome of patients with ruptured blood-blister like aneurysm (BBLA) in our institution by comparing microsurgical selective treatment to endovascular treatment using flow-diverter stent (FD). Our study included 18 consecutive patients treated for BBLA between 2004 and 2020. Until 2014, microsurgery was preferred in all patients with BBLA (n = 10). Significant postoperative morbi-mortality was recorded at this time and led us to change therapeutic strategy and to favor FD as first-line treatment in all patients (n = 8). Postprocedural complications and BBLA occlusion were recorded. High WFNS score (> 2) was noted in 6 patients of microsurgical group and in 2 of endovascular group. In microsurgical group, ischemic lesions were noted in 6 patients and led to death in 3 patients. Immediate BBLA occlusion was obtained in all patients. Favorable outcome after 3 months (mRS < 3) was recorded in 4 of the 7 survivors. In endovascular group, ischemic lesions were noted in 4 patients. One patient died from early postprocedural BBLA rebleeding. Scarpa hematoma was noted in 3 patients with surgical evacuation in 1. Persistent BBLA at 3 months was recorded in 4 patients without rebleeding, but further FD was required in 1 with growing BBLA. Favorable outcome was noted in 6 of the 7 survivors. Although, rate of morbi-mortality appear lower in patients treated with FD, neurological presentation was better and BBLA diagnosis remains questionable in this group. Moreover, persistent BBLA imaging with potential risk of rebleeding after FD deserves to be discussed.

Preinduction cervical ripening with prostaglandin E2: influence on psychomotor evolution in the first year

The long-term effects of elective preinduction of labor at term by extra-amniotic instillation of prostaglandin E2 in methylhydroxyethylcellulose gel were evaluated in 20 children. No untoward effect of this procedure on the neurologic state of the newborn or the psychomotor development of the children during the first 12 months was found.