Aneurysm Isolation is Associated with Complete Occlusion of Aneurysms After Flow Diverter Treatment.

PURPOSE: Some aneurysms remain patent after treatment with flow diverters (FD) due to residual blood flow in the aneurysm. Several studies have proposed that branches and residual flow are associated with delayed aneurysm occlusion. We propose that aneurysm isolation (i.e., the complete disconnection of the aneurysm from surrounding vessels) might be a possible factor facilitating aneurysm occlusion. This study aimed to determine if aneurysm isolation was a factor associated with aneurysm occlusion after FD treatment. METHODS: We reviewed 80 internal carotid artery (ICA) aneurysms treated with FDs between October 2014 and April 2021. Aneurysm isolation was assessed in high-resolution cone-beam computed tomograms at the end of each treatment. Aneurysms with incorporated branches and those with connections to other branches due to stent malapposition were deemed to be nonisolated. Other factors, such as patient age, sex, anticoagulant use, aneurysm size, adjunct coil use, and the presence of incorporated branches, were considered. The degree of aneurysm occlusion (complete or incomplete) was assessed by follow-up angiograms 12 months after treatment. RESULTS: Complete occlusion was achieved in 57 of 80 aneurysms (71%). Completely occluded aneurysms had a significantly higher ratio of isolation compared to incompletely occluded aneurysms (91.2% vs. 69.6%, P = 0.032). Multivariate logistic regression analysis showed that aneurysm isolation was the sole significant predictor of complete aneurysm occlusion (odds ratio, OR 19.38; 95% confidence interval, CI 2.280-164.657; P = 0.007). CONCLUSION: Aneurysm isolation is a significant factor contributing to complete occlusion after FD treatment.

Ventral Clival Branch of the Ascending Pharyngeal Artery as a Transosseous Feeder of an Arteriovenous Fistula Surrounding the Clival Lesions.

PURPOSE: Arteriovenous fistulas (AVFs) adjacent to the clivus, such as cavernous sinus dural AVFs (CSDAVFs) and condylar AVFs, sometimes have an intraosseous shunted pouch and recruit blood supply from transosseous feeders. Precise analysis of transosseous feeders regarding the clival lesion has not yet been performed. Therefore, this study aimed to clarify the characteristics and identity of transosseous feeders in clival lesions. METHODS: Patients with CSDAVFs and condylar AVFs, who underwent high-resolution cone-beam computed tomography or three-dimensional rotational angiography in our institute, were included. The frequency, type of branch, penetrating point, and termination of intraosseous feeders were retrospectively evaluated. RESULTS: A total of 31 patients with 36 lesions in CSDAVFs and 8 patients with 8 lesions in condylar AVFs underwent angiography. For CSDAVFs, 38 transosseous feeders were detected in 23 out of 31 patients, including 22 in the pharyngeal branch of the ascending pharyngeal artery (APhA), 6 in the hypoglossal branch of the APhA, 6 in the accessory meningeal artery, 3 in the meningohypophyseal trunk (MHT), and 1 in the anterior branch of the middle meningeal artery. For condylar AVFs, 24 transosseous feeders were detected in all 8 patients, including 11 in the pharyngeal branches of the APhA, 7 in the hypoglossal branch of the APhA, 6 in the segmental artery from the vertebral artery, and 2 in the MHT. CONCLUSION: Transosseous feeders of AVFs around the clivus, which are frequently seen in AVFs of this area, mainly arise from ventral clival branches and from pharyngeal branches of the APhA.

Involvement of the optic pathway and outcome of visual function in patients with neurohypophyseal germ cell tumor.

BACKGROUND: Patients with neurohypophyseal germ cell tumors (GCTs) typically present with visual problems. Hence, this study aimed to assess optic pathway involvement based on clinical and radiological findings and to validate the outcome of visual function. METHODS: A total of 16 patients with newly diagnosed neurohypophyseal GCTs who were treated at the University of Tsukuba Hospital between 2000 and 2020 were included in this study. RESULTS: The median interval from symptom onset to diagnosis was 173.5 days (range, 33-1588 days). Patients with visual disturbance at diagnosis had a longer time to diagnosis compared with those without. Ophthalmologic abnormalities were frequently observed, with an incidence rate of 69%. Fifty percent of patients exhibited optic pathway involvement detected via magnetic resonance imaging (MRI). Visual impairment was more severe in the patients with optic pathway involvement (p = 0.002). Post-treatment visual impairment was improved but was still significantly severe in patients with optic pathway involvement than in those without involvement (p = 0.010). Visual field deficit more likely remained with an improvement rate of 50%, whereas the improvement rate of visual acuity was 78%. Further, none developed late-onset visual deterioration during the follow-up period. CONCLUSIONS: Visual disturbance and optic pathway involvement are common in neurohypophyseal GCTs. Visual impairment particularly in patients with optic pathway involvement on MRI is more likely to remain at follow-up, although the outcome of visual function is acceptable in most cases.

Unusual Form of Obstructive Hydrocephalus in Association with 6q Terminal Deletion Syndrome: A Case Report and Literature Review.

INTRODUCTION: Terminal deletion of chromosome 6q is a rare chromosomal abnormality associated with intellectual disabilities and various structural brain abnormalities. We present a case of 6q terminal deletion syndrome with unusual magnetic resonance imaging (MRI) findings in a neonate. CASE PRESENTATION: The neonate, who was prenatally diagnosed with dilation of both lateral ventricles, was born at 38 weeks of gestation. MRI demonstrated abnormal membranous structure continuing to the hypertrophic massa intermedia in the third ventricle that had obscured the cerebrospinal fluid pathway, causing hydrocephalus. G-band analysis revealed a terminal deletion of 6q with the karyotype 46, XY, add(6)(q25.3) or del(6)(q26). He underwent ventriculoperitoneal shunt successfully, and his head circumference has been stable. DISCUSSION/CONCLUSION: 6q terminal deletion impacts the molecular pathway, which is an essential intracellular signaling cascade inducing neurological proliferation, migration, and differentiation during neuronal development. In patients with hydrocephalus in association with hypertrophy of the massa intermedia, this chromosomal abnormality should be taken into consideration. This case may offer an insight into the pathogenesis of hydrocephalus in this rare chromosomal abnormality.

Delayed Brain Edema and Swelling following Craniectomy for Evacuation of an Epidural Abscess that Improved by Cranioplasty: Case Report.

We report a unique case of delayed brain swelling following craniectomy that improved rapidly after cranioplasty, and discuss the potential mechanism underlying this delayed and reversible brain swelling. A 22-year-old woman developed surgical site infection after removal of a convexity meningioma. Magnetic resonance imaging revealed an epidural abscess around the surgical site. Subsequently, the abscess was evacuated, and the bone flap was removed. Later, brain edema around the skull defect emerged and progressed gradually, despite resolution of the infection. The edematous brain developed focal swelling outward through the bone defect without ventricle dilatation. Because we suspected that the edema and swelling were caused by the state of the bone defect, we performed a cranioplasty 10 weeks after the bone flap removal, and brain edema improved rapidly. We hypothesized that the brain edema was initially caused by surgical stress and inflammation, followed by compression of cortical veins between the dural edge and brain tissue, leading to disruption of venous return and exacerbation of brain edema. When delayed focal brain edema and external swelling progress gradually after bone flap removal, after excluding other pathological conditions, cranioplasty should be considered to improve cortical venous congestion caused by postsurgical adhesion.