Coiling Using Dual Microcatheter Technique—A Novel Approach

Posterior circulation aneurysms are difficult to treat, and if an incorporated artery is arising from the neck of aneurysm, management becomes much more challenging. Here, we are describing a novel technique used to treat a patient with a large, wide-necked left vertebral artery (VA)-posterior inferior cerebellar artery (PICA) junctional aneurysm. PICA seems to be arising from the aneurysm neck, but the aneurysm neck was not very clearly defined. So, we placed a second microcatheter into PICA, which not only allowed the coils to be placed in the aneurysm, without disrupting the flow through PICA but also helpful in assessing the aneurysmal occlusion. This technique allowed coils to be placed successfully without compromising flow through PICA.

Eosinophilic meningitis following suboccipital craniotomy without bovine dural graft: illustrative case

BACKGROUND Eosinophilic meningitis is a rare known complication after brain surgery associated with duraplasty using artificial bovine graft. However, eosinophilic meningitis after craniotomy without bovine dural graft has not been reported. OBSERVATIONS A 48-year-old female presented with lateral medullary infarction caused by a vertebral artery dissecting aneurysm incorporating the posterior inferior cerebellar artery (PICA). The authors performed occipital artery–PICA anastomosis and repaired the dura by primary suture without bovine graft. Thereafter, endovascular internal trapping using coils was conducted. Severe headache developed at postoperative day 17, and the patient was diagnosed with eosinophilic meningitis. After administration of a high-dose corticosteroid for 2 weeks, her symptoms and laboratory findings were improved. LESSONS Postoperative eosinophilic meningitis is rarely related to craniotomy without using bovine graft. Neurosurgeons should consider the possibility of eosinophilic meningitis after craniotomy without a xenogeneic dural material.

Anatomical variations of posterior inferior cerebellar artery (PICA) on digital subtraction angiography (DSA)

Introduction: The posterior inferior cerebellar artery (PICA) often exhibits anatomical variations at the craniovertebral junction. Few studies investigated variations of the posterior inferior cerebellar artery, and the prevalence of other variations has not been reported. The study aimed to identify variations of the posterior inferior cerebral artery using cerebral Digital Subtraction Angiography (DSA). Method: 50 patients underwent 64-slice cerebral Digital Subtraction Angiography. Four types of variations were observed. Results: Out of a total of 50 patients, 23 (46%) were males and 27 (54%) females (all age groups). Our study has shown the utility of the 2 sequences - fluoroscopy and cine. All 2 sequences have their significance in evaluating anatomical variations in PICA. Only 20% of the 50 patients had all the posterior inferior cerebellar artery without anatomical variations. Anatomic variations commonly involve the distal segment of the vertebral artery (VA). Most of them are seen arising from the C1, C2, and both C1 and C2 origins. Anatomic variations involve arising from the C1 origin in 9 patients, C2 origin in 11 patients, C1 & C2 origin in 8 patients, and other variations observed in 12 patients. Conclusion: Variations of the posterior inferior cerebellar artery can be easily evaluated by cerebral Digital Subtraction Angiography (CDSA). Recognizing and reporting them at cerebral CDSA may be clinically important. Surgeons should be mindful of this variation during operations.

Predicting Early Loss of Lateral Spread Response before Decompression in Hemifacial Spasm Surgery

Recent studies have shown the evocation of lateral spread response (LSR) due to the compression of the facial nerve in hemifacial spasm (HFS). Intraoperative monitoring (IOM) of LSR could help locate neurovascular conflicts and confirm adequate micro-vascular decompression (MVD) while treatment of hemifacial spasm (HFS). However, studies on early LSR loss before decompression in HFS surgery are sparse, indicating the need to understand various perceptions on it. Therefore, we retrospectively analyzed 50 adult HFS patients who underwent MVD during the period of September 2018–June 2021. We employed IOM combining traditional LSR (tLSR) and dual LSR (dLSR). One patient was excluded owing to the lack of LSR induction throughout the surgery, while 49 were divided into groups A (n = 14) and B (n = 35), designated as with or without early LSR loss groups, respectively, and offending vessels were analyzed. The mean age of group A patients was significantly younger (47.8 ± 8.6) than that of group B (53.9 ± 10.6) (p = 0.0393). The significant predominating offending vessel in group A was the anterior inferior cerebellar artery (AICA, 78.57%). However, group B included those with AICA (28.57%), posterior inferior cerebellar artery (PICA, 22.86%), vertebral artery (VA) involved (25.71%), and combined AICA and PICA (22.86%). Group B exhibited poorer clinical outcomes with more complications. Conclusively, early LSR loss might occur in the younger population, possibly due to the AICA offending vessel. The compression severity of offending vessels may determine the occurrence of early LSR loss.

Clinical and radiological risk factors for rupture of vertebral artery dissecting aneurysm: significance of the stagnation sign

OBJECTIVE The aim of this study was to investigate the clinical and radiological factors associated with the rupture of a vertebral artery dissecting aneurysm (VADA) and to evaluate whether the stagnation sign is a significant risk factor for rupture of VADA. METHODS Clinical and radiological variables of 117 VADAs treated in a tertiary hospital from September 2008 to December 2020 were retrospectively reviewed. The stagnation sign is defined as the finding of contrast agent remaining in the lesion until the venous phase of angiography. Univariate and multivariate analyses were executed to reveal the associations between rupture status and VADA characteristics. RESULTS The rate of ruptured VADAs was 29.1% (34 of 117) and the stagnation sign was observed in 39.3% (46 of 117). Fusiform shape (OR 5.105, 95% CI 1.591–16.383, p = 0.006), irregular surface (OR 4.200, 95% CI 1.412–12.495, p = 0.010), posterior inferior cerebellar artery (PICA) involvement (OR 3.788, 95% CI 1.288–11.136, p = 0.016), and the stagnation sign (OR = 3.317, 95% CI 1.131–9.732, p = 0.029) were significantly related to rupture of VADA in multivariate logistic regression analysis. CONCLUSIONS This study showed that fusiform shape, irregular surface, PICA involvement, and the stagnation sign may be independent risk factors for the rupture of VADA. Therefore, when the potential risk factors are observed in unruptured VADA, more aggressive treatment rather than follow-up or medical therapy may be considered.

Vertebrobasilar dissecting aneurysms: microsurgical management in 42 patients

OBJECTIVE Vertebrobasilar dissecting (VBD) aneurysms are rare, and patients with these aneurysms often present with thromboembolic infarcts or subarachnoid hemorrhage (SAH). The morphological nature of VBD aneurysms often precludes conventional clip reconstruction or coil placement and encourages parent artery exclusion or endovascular stenting. Treatment considerations include aneurysm location along the vertebral artery (VA), the involvement of the posterior inferior cerebellar artery (PICA), and collateral blood flow. Outcomes after endovascular treatment have been well described in the neurosurgical literature, but microsurgical outcomes have not been detailed. Patient outcomes from a large, single-surgeon, consecutive series of microsurgically managed VBD aneurysms are presented, and 3 illustrative case examples are provided. METHODS The medical records of patients with dissecting aneurysms affecting the intracranial VA (V4), basilar artery, and PICA that were treated microsurgically over a 19-year period were reviewed. Patient demographics, aneurysm characteristics, surgical procedures, and clinical outcomes (according to modified Rankin Scale [mRS] scores at last follow-up) were analyzed. RESULTS Forty-two patients with 42 VBD aneurysms were identified. Twenty-six aneurysms (62%) involved the PICA, 14 (33%) were distinct from the PICA origin on the V4 segment of the VA, and 2 (5%) were located at the vertebrobasilar junction. Thirty-four patients (81%) presented with SAH with a mean Hunt and Hess grade of 3.2 at presentation. Six (14%) of the 42 patients had been previously treated using endovascular techniques. Nineteen aneurysms (45%) underwent clip wrapping, 17 (40%) were treated with bypass trapping, and 6 (14%) underwent parent artery sacrifice. The complete aneurysm obliteration rate was 95% (n = 40), and the surgical complication rate was 7% (n = 3). The 8 patients with unruptured VBD aneurysms were significantly more likely to be discharged home (n = 6, 75%) compared with 34 patients with ruptured aneurysms (n = 9, 27%; p = 0.01). Good outcomes (mRS score ≤ 2) were observed in 20 patients (48%). Eight patients (19%) died. CONCLUSIONS These data demonstrate that patients with VBD aneurysms often present after a rupture in poor neurological condition, but favorable results can be achieved with open microsurgical repair in almost half of such cases. Microsurgery remains a viable treatment option, with the choice between bypass trapping and clip wrapping largely dictated by the specific location of the aneurysm and its relationship to the PICA.

Abstract 1122‐000052: Endovascular Management of Infectious PICA Aneurysm in the Setting of Recent Dental Work

Introduction : Infectious intracranial aneurysms (IIA) of the posterior inferior cerebellar artery (PICA) are exceedingly rare and have been infrequently reported. IIAs are typically distal and located in the anterior circulation, particularly the middle cerebral artery and its distal branches. Etiology is secondary to hematogenous spread of septic emboli from a proximal source such as infective endocarditis. Few cases have documented an association between IIA and dental disease or procedures. We describe a rare case of an infectious PICA aneurysm in the setting of recent dental work and successfully treated with endovascular intervention. Methods : An 88‐year‐old male with medical history of atrial fibrillation on anticoagulation presented with one month duration of recurrent falls and progressive generalized weakness. CT head demonstrated left cerebral hemorrhage with scattered subarachnoid hemorrhage. MRI brain noted a rounded enhancing intra‐axial lesion located at the left paramedian cerebellum measuring 7 mm in maximal dimension. Further investigation with cerebral angiography demonstrated an infectious intracranial aneurysm of the left PICA. He underwent workup with an echocardiogram that noted a mobile echo density on the aortic valve consistent with a vegetation. Blood cultures were positive for Streptococcus salivarius and viridans. Investigation revealed that he had recent dental work performed and missed taking his prophylactic amoxicillin. Infectious disease was consulted and etiology was determined to be seeding of aortic valve from recent dental procedure that ultimately led to IIA formation. Results : Patient was treated with 6‐week course of intravenous ceftriaxone and underwent glue embolization for his left PICA aneurysm. Post embolization angiogram did not reveal any evidence of contrast filling within the aneurysm. He tolerated the procedure well with no complications and was subsequently discharged to inpatient rehabilitation with a modified Rankin scale (mRS) score of 3. Conclusions : IIAs of PICA in the setting of recent dental procedures are exceptionally rare and challenging to diagnose. They may be clinically silent until rupture and are usually identified incidentally on imaging or during autopsy. Physicians should maintain vigilance for this unique entity as prompt recognition and timely intervention may prevent severe morbidity and mortality.

Abstract 1122‐000148: Rare Anterior Inferior Cerebellar Artery Origin of Middle Meningeal Artery

Introduction : Middle meningeal artery (MMA) anatomy has very important surgical implications during endovascular and open based skull procedures. Various anatomical origins have been identified in the literature besides its most common origin as the largest branch of the maxillary artery. It runs parallel and close contact of the lateral skull face therefore during trauma to this area is prone to rupture resulting in subdural hemorrhage(SDH). In our case report, we present its peculiar origin from anterior inferior cerebellar artery which has never been reported before. The origin of MMA may reflects the risk involved with embolization therapy for chronic SDH. Methods : A case of MMA originated form AICA. A literature review was conducted of reports of MMA origins. Results : A 35‐year‐old male with a history of alcohol abuse presented to the ED after falling down from the stairs. In the ED, the patient had multiple episodes of seizures along with respiratory distress therefore was intubated due to concern of airway protection. CT head showed bilateral SDH. Patient underwent diagnostic angiogram for possible bilateral embolization of MMA. During the procedure, the left MMA origin was seen from the AICA whereas the right MMA arising from the external carotid artery. Embolization of the left MMA was aborted. Patient remained intubated and was later transferred to a long term care facility. Conclusions : In the last 80 years, the anatomy of the MMA has been part of the discussion of various literature. Seeger et.al, highlighted the embryological changes manifested as anastomosis between Sphenomaxillary artery and lateral pontine artery resulting in origin of MMA from Basilar artery along with absence of foramen spinosum. Since 1973, multiple literature highlighted the origin of MMA including the lacrimal artery, ICA, ascending pharyngeal artery, opthalmic and occipital arteries. Recently, In 2011 Kuruvuilla et.al showed the origin of MMA from posterior inferior cerebellar artery. MMA clinical significance can be seen in multiple diseases. Older populations with chronic subdural hematomas, embolization of MMA has shown to be a less invasive and cost effective procedure. In patients with anterior and middle cranial fossa meningiomas embolization of MMA has been a crucial part of management. Similarly, understanding of its anatomy is also important while treating MMA aneurysm or pseudoaneurysms. In our case, the origin of middle meningeal artery from AICA has been significant as it supplies the posterior fossa structures and was not reported in the literature before, hence the procedure was aborted. This anatomical variant has shown us a new light upon embryological evolution and has helped us widen the horizons of our approach towards brain vasculature. This finding will help the future Interventionists to develop new ways of embolization of the MMA and understanding its anatomy.