Brainstem Compression Research Articles

Early Postoperative Magnetic Resonance Imaging Findings Related to Electrocauterization for Cerebellar Reduction During Chiari Decompression Surgery.

Cerebellar tonsillar reduction or resection can be performed as part of the surgical management of Chiari type 1 malformation when it is accompanied by symptomatic brainstem compression or syringomyelia. The purpose of this study is to characterize the early postoperative magnetic resonance imaging (MRI) findings in patients with Chiari type 1 malformations who undergo cerebellar tonsillar reduction via electrocautery. The extent of cytotoxic edema and microhemorrhages demonstrated on MRI scans obtained within 9 days following surgery was assessed and correlated with neurological symptoms. Cytotoxic edema was found on all postoperative MRI examinations included in this series, with superimposed hemorrhage in 12 of 16 patients (75%) and was primarily located along the margins of the cauterized inferior cerebellum. Cytotoxic edema was present beyond the margins of the cauterized cerebellar tonsils in 5 of 16 patients (31%) and was associated with new focal neurological deficits in 4 of 5 patients (80%). Cytotoxic edema and hemorrhages along the cerebellar tonsil cautery margins can be expected findings in early postoperative MRI in patients who undergo Chiari decompression accompanied by tonsillar reduction. However, the presence of cytotoxic edema beyond these regions can be associated with new focal neurological symptoms.

Symptoms: Sudden Sensorineural Hearing Loss and Aural Fullness

Symptoms: Sudden Sensorineural Hearing Loss and Aural Fullness

Association Between Serum Homocysteine Concentration, Aneurysm Wall Inflammation, and Aneurysm Symptoms in Intracranial Fusiform Aneurysm

The pathophysiology of fusiform intracranial aneurysm (FIA) involves inflammatory processes, and homocysteine plays a role in the inflammatory processes in the vessel wall. Moreover, aneurysm wall enhancement (AWE) has emerged as a new imaging biomarker of aneurysm wall inflammatory pathologies. To investigate the pathophysiological mechanisms of aneurysm wall inflammation and FIA instability, we aimed to determine the associations between the homocysteine concentration, AWE, and FIAs' related symptoms. We retrospectively reviewed the data of 53 patients with FIA who underwent both high-resolution magnetic resonance imaging and serum homocysteine concentration measurement. FIAs' related symptoms were defined as ischemic stroke or transient ischemic attack, cranial nerve compression, brainstem compression, and acute headache. The contrast ratio of the signal intensity of the aneurysm wall to the pituitary stalk (CRstalk) was used to indicate AWE. Multivariate logistic regression and receiver operating characteristic (ROC) curve analyses were performed to determine how well the independent factors could predict FIAs' related symptoms. Predictors of CRstalk were also investigated. Spearman's correlation coefficient was used to identify the potential associations between these predictors. Fifty-three patients were included, of whom 23 (43.4%) presented with FIAs' related symptoms. After adjusting for baseline differences in the multivariate logistic regression analysis, the CRstalk (odds ratio [OR]=3.207, P=.023) and homocysteine concentration (OR=1.344, P=.015) independently predicted FIAs' related symptoms. The CRstalk was able to differentiate between FIAs with and without symptoms (area under the ROC curve [AUC]=0.805), with an optimal cutoff value of 0.76. The homocysteine concentration could also differentiate between FIAs with and without symptoms (AUC=0.788), with an optimal cutoff value of 13.13. The combination of the CRstalk and homocysteine concentration had a better ability to identify symptomatic FIAs (AUC=0.857). Male sex (OR=0.536, P=.018), FIAs' related symptoms (OR=1.292, P=.038), and homocysteine concentration (OR=1.254, P=.045) independently predicted the CRstalk. A higher serum homocysteine concentration and greater AWE indicate FIA instability. Serum homocysteine concentration may be a useful biomarker of FIA instability; however, this needs to be verified in future studies.

Surgical outcomes of premeatal and retromeatal cerebellopontine angle meningioma in Vietnam: a single-center prospective cross-sectional study.

A prospective study on 33 patients treated with microsurgery from August 2020 to May 2022 at the Neurosurgery Center, Viet Duc University Hospital. The mean age of 27 females (85%) and 6 (15%) males was 54±12 years. Based on their location to the IAC, there were 16 premeatal cases (49%) (anterior to the IAC) and 17 retromeatal cases (15%) (posterior to the IAC). The time of diagnosis of the retromeatal group was later (16.5 vs. 9.7 months), the average tumor size of the 2 groups was not different, but when there was brainstem compression, the average tumor size of retromeatal group was larger (49 vs. 44mm). The clinical presentations of the retromeatal group were related to the cerebellar symptoms, while trigeminal neuropathy symptoms all came from the premeatal group. Gross total resection of the premeatal group was 31% and of the retrometal group was 71%. The results of preserving the facial nerve function of the premeatal group were lower (44 vs. 82%). Postoperative Karnofsky score of the retromeatal group improved, while the premeatal group did not change. Classification of CPA meningiomas according to their location to the IAC plays an important role in diagnosis and treatment, affecting clinical symptoms, surgical strategy as well as surgical outcomes.

A Case of Infant-type Hemispheric Glioma with NTRK1 fusion (P9-13.003)

<h3>Objective:</h3> Not applicable <h3>Background:</h3> The incidence of childhood central nervous system tumors in infants is about 6 per 100,000 children with glioma having the highest incidence at 1.38 per 100,000. A study by Wu et al. showed recurrent fusion of the <i>NTRK</i> gene in 10% of non-brainstem high grade glioma in very young children suggesting an oncogenic effect of the <i>NTRK</i> fusion genes. Here we present a rare case of a full-term neonate who was noted to have widely splayed sutures and a bulging fontanelle at birth who was found to have infant-type hemispheric glioma with <i>NTRK1</i> fusion. <h3>Design/Methods:</h3> Not applicable <h3>Results:</h3> A full-term infant with normal prenatal course, including a 20-week anatomy scan, was born with widely splayed sutures, bulging anterior fontanelle and head circumference &gt;99^th percentile (40 cm). Head ultrasound showed severe hydrocephalus and a large intracranial mixed echogenicity lesion in the left cerebral hemisphere with hemorrhage. He had sustained leftward gaze, and video EEG revealed seizures. MRI demonstrated a large 6×7cm lesion, hydrocephalus with subfalcine herniation and mass effect on the brainstem (figure, A–B). He underwent biopsy and ventriculoperitoneal shunt placement. MRI 2 weeks later showed tumor enlargement, obstructive hydrocephalus and severe brainstem compression (figure, C–D). Pathology was consistent with infant-type hemispheric glioma with <i>NTRK1</i> fusion. Due to the dismal prognosis, the family prioritized palliative care. <h3>Conclusions:</h3> Infant-type hemispheric glioma, previously termed glioblastoma (GBM), is a rare, rapidly-growing congenital tumor, and prenatal imaging is often normal. Mixed-age hemorrhages and diffusion restriction is suggestive of the diagnosis. The neurotrophic tyrosine receptor kinase (NTRK) genes <i>NTRK1, NTRK2</i>, and <i>NTRK3</i> are involved in infant-type hemispheric gliomas and are typically high grade in histology. A recent study by Torre et al. showed most <i>NTRK-</i>fused gliomas were hemispheric and had a higher prevalence in non-brainstem high grade gliomas in patients younger than 3 years old. <b>Disclosure:</b> Dr. Garcia has nothing to disclose. Dr. Bell has nothing to disclose. Dr. Nelson has nothing to disclose. Dr. Miller has nothing to disclose. Dr. Segal has nothing to disclose.

Endovascular treatment of intracranial vertebral artery dissecting aneurysm, a case series study with two years follow up on complications

BackgroundThis study is aimed to analyze the clinical outcomes of endovascular treatments for patients with intracranial vertebral artery dissecting aneurysms. MethodsClinical data of 32 patients with vertebral artery dissecting aneurysms who underwent endovascular procedures in the Department of Neurosurgery of our University from January 2016 to December 2019 were retrospectively analyzed. Nine cases were treated with endovascular occlusion; 23 cases received reconstructive treatment, including 20 cases of stent combined with coil embolization, and 3 cases of stent implantation. The angiography taken at 3–22 months after surgery was reviewed. ResultsThe endovascular treatments for all 32 cases were successful. Thirty-one cases had no postoperative complications during index hospital. Mid-term follow-up showed that: 27 cases (84%) had embolism; 5 cases (16%) had recurrence, of which 4 cases were treated again with endovascular procedures followed with no further complications and no recurrence, and 1 case received closely monitor but no reoperation. During an average follow-up of 10.5 months, except for one case that was self-discharged due to end-stage brainstem compression and respiratory failure, the rest of the patients were in stable conditions without bleeding or infarction. ConclusionEndovascular treatment of intracranial vertebral artery dissecting aneurysms is safe and effective. Recurrent vertebral artery dissecting aneurysms can be treated with endovascular reoperations with satisfactory outcomes.

Predictors of clinical outcomes in space-occupying cerebellar infarction undergoing suboccipital decompressive craniectomy.

Despite current clinical guidelines recommending suboccipital decompressive craniectomy (SDC) in cerebellar infarction when patients present with neurological deterioration, the precise definition of neurological deterioration remains unclear and accurate timing of SDC can be challenging. The current study aimed at characterizing whether clinical outcomes can be predicted by the GCS score immediately prior to SDC and whether higher GCS scores are associated with better clinical outcomes. In a single-center, retrospective analysis of 51 patients treated with SDC for space-occupying cerebellar infarction, clinical and imaging data were evaluated at the time points of symptom onset, hospital admission, and preoperatively. Clinical outcomes were measured by the mRS. Preoperative GCS scores were stratified into three groups (GCS, 3-8, 9-11, and 12-15). Univariate and multivariate Cox regression analyses were performed using clinical and radiological parameters as predictors of clinical outcomes. In cox regression analysis GCS scores of 12-15 at surgery were significant predictors of positive clinical outcomes (mRS, 1-2). For GCS scores of 3-8 and 9-11, no significant increase in proportional hazard ratios was observed. Negative clinical outcomes (mRS, 3-6) were associated with infarct volume above 6.0 cm3, tonsillar herniation, brainstem compression, and a preoperative GCS score of 3-8 [HR, 2.386 (CI, 1.160-4.906); p = 0.018]. Our preliminary findings suggest that SDC should be considered in patients with infarct volumes above 6.0 cm3 and with GCS between 12 and 15, as these patients may show better long-term outcomes than those in whom surgery is delayed until a GCS score below 11.

482 Triple Therapy Versus Dual Antiplatelet Therapy for Dolichoectatic Vertebrobasilar Fusiform Aneurysms Treated With Flow Diverters: The Last Frontier?

INTRODUCTION: Dolichoectatic vertebrobasilar fusiform aneurysms (DVBFAs) have poor natural history when left untreated and high morbimortality when treated with microsurgery. Flow diversion (FD) with dual-antiplatelet therapy (DAPT) is feasible but carries a high risk of perforator occlusion and progression of brainstem compression. Seeking better hopes for these patients, experts across the US started using triple-therapy (DAPT plus oral anticoagulation) after FD treatment in attempt to improve their clinical outcomes. The rationale was to preserve perforator patency while vessel remodeling occurs. The current study is the result of this multicenter effort. METHODS: Retrospective data collection from 8 US centers. Only DVBFAs treated with flow-diversion and either triple-therapy or DAPT alone were included. Patient and aneurysms' characteristics, and clinical and angiographic outcomes were compared. RESULTS: The groups (DAPT, n = 13 vs Triple-therapy, n = 14) were similar in age, sex, clinical presentation, baseline disability, aneurysm characteristics, median number of flow-diverters, and adjunctive coiling. Radial access use was significantly higher in the triple-therapy group (71.4% vs. 15.3%, P = 0.006). Acute ischemic stroke rate was lower in the triple-therapy group (7.1% vs. 30.8%, P = 0.167). Overall rate of modified Rankin Scale score decline due to either ischemic stroke or worsening of brainstem compression was significantly lower in the triple-therapy group (7.1% vs. 69.2%, P = 0.001). Overall rate of hemorrhagic complications was numerically higher in the triple-therapy group (28.6% vs. 7.7%, P = 0.162). The rate of moderate-to-severe disability at last follow-up was significantly lower in the triple-therapy group (21.4% vs. 76.9%, P = 0.007). I. CONCLUSIONS: Patients with DVBFAs treated with FD and triple-therapy had less ischemic strokes, less symptom progression, and overall better outcomes at last follow-up than similar patients and aneurysms managed with DAPT alone.

Emotional Lability as a Symptom of Extra-axial Posterior Fossa Tumors: a Case-Control Review of Neuroanatomy and Patient-Reported Quality of Life.

Introduction Emotional lability (EL), the uncontrollable and unmotivated expression of emotion, is a rare and distressing symptom of brainstem compression. In published case reports, EL from an extra-axial posterior fossa tumor was alleviated by tumor resection. The primary aim herein was to radiographically establish the degree of compression from mass lesions onto brainstem structures. Secondarily, we compared changes in patient-reported quality of life (QOL) pre- and postoperatively. Methods A retrospective review of posterior fossa tumors treated between 2002 and 2018 at Vancouver General Hospital revealed 11 patients with confirmed EL. Each case was matched to three controls. A lateral brainstem compression scale characterized mass effect at the level of the medulla, pons, and midbrain in preoperative axial T2-weighted fluid-attenuated inversion recovery magnetic resonance imaging (FLAIR MRI) scans. Compression and clinical variables were compared between patient groups. Short Form-36 version 1 health surveys were retrospectively obtained from patient charts to compare pre- versus postoperative changes in survey scores between EL and control patients. Results EL symptoms ceased postoperatively for all EL patients. EL tumors exert greater compression onto the pons ( p = 0.03) and EL patients more commonly have cerebellar findings preoperatively ( p = 0.003). Patients with EL-causing tumors experienced greater improvement postoperatively in "Health Change" ( p = 0.05), which was maintained over time. Conclusion Findings suggest that compression onto the pons inhibits control over involuntary, stereotyped expression of emotion. This adds to evidence that EL may be attributed to cerebellum deafferentation from cortical and limbic structures through the basis pontis, leading to impaired modulation of emotional response. QOL results augment benefits of offering patients EL-alleviating tumor resection surgery.

Abstract Number ‐ 228: Two Cases of Vertebrobasilar Dolichoectasia +/‐ Obstructive Hydrocephalus

Introduction Dolichoectasia; “dolichos'' and “ectasia” respectively meaning elongation and distention of blood vessels is a process by which arteries undergo deterioration of the tunica intima or tunica media, resulting in smooth muscle atrophy.1 It can be atherosclerotic, non‐atherosclerotic, and dissection‐related. Prolonged hypertension resulting in breakdown and remodeling of collagen‐elastin meshwork produces the atherosclerotic subtype, though hyperlipidemia also plays a role. The incidence is approximately 3%, higher in males.2 Vessels commonly affected by dolichoectasia are in the vertebrobasilar system but the internal carotid arteries are also at risk. Vertebrobasilar dolichoectasia (VBDE) is radiographically defined by basilar artery diameter &gt; 4.5 mm, though it is sometimes overlooked due to healthy variations in basilar tortuosity and diameter. Smoker’s criteria includes artery diameter, laterality, and bifurcation height.3 Neurovascular compression often occurs, but high‐risk complications of VBDE such as hemorrhagic or ischemic stroke, TIA, brainstem compression, hydrocephalus, or subarachnoid hemorrhage are also possible.4 We present two cases of ventriculomegaly in the setting of VBDE. Methods Case Report Results Case #1: A 40 year‐old man with history of hypertension, gout, anal fissures, and bicuspid aortic valve presented to the hospital for intermittent visual obscuration for 2 weeks. He described it as a “Polaroid picture: starting dark and slowly developing” featuring positional exacerbation with Valsalva, leaning forward, and laying flat. Examination revealed bilateral papilledema, right eye ptosis, and right 6th nerve palsy. CT head showed hydrocephalus. CTA and CTV were negative. MRI brain with contrast showed dilated lateral ventricles (left &gt; right) and anterior third ventricle lacking significant transependymal CSF flow. The distal basilar was tortuous extending towards the mid‐portion of the third ventricle (Figure 1). A precipitating factor was thought to be an epidural for anal fissure surgery 2 months prior. Initially treated with acetazolamide, the patient later underwent endoscopic third ventriculostomy (ETV). One‐year follow‐up showed significant improvement of papilledema with minimal residual visual field deficits. Case #2: A 71 year‐old man with history of atrial fibrillation presented to the Neurology clinic for memory loss. It started with misplacing belongings, complicated by an episode of getting lost while driving to a familiar location. Examination showed 1/5 word recall at 5 minutes and mild impairment of serial sevens and abstract thinking. MRI brain revealed dilatation of the lateral and third ventricles out of proportion to the sulci and fourth ventricle, dolichoectatic basilar artery up to 8 mm with superior displacement of nearby structures and effacement of the anterior third ventricle. Repeat MRI with CSF flow one month later showed unchanged ventricular dilatation favored secondary to volume loss without evidence of an obstructive process. Conclusions These cases characterize the rare phenomenon of VBDE and highlights the importance of acquiring MRI with CSF flow when it presents with hydrocephalus.

Misdiagnosis of Cerebellar Infarcts and Its Outcome.

Cerebellar infarction, a rare category of stroke, is often misdiagnosed but not given much importance in the available literature. Its presentation overlaps with symptoms of other neurologic, cardiovascular, gastrointestinal, and systemic conditions and therefore is nonspecific. Early diagnosis and management of cerebellar strokes are of utmost importance as the lack of a proper diagnosis may increase overall morbidity and mortality. Lack of awareness of the warning signs and symptoms, non-specificity of symptoms, absence of neurological deficits, and imaging discrepancies are some of the factors contributing to misdiagnosis and delayed treatment. If symptomatology is considered, it is found that symptoms of posterior circulation stroke were more frequently misdiagnosed compared to anterior circulation. Nausea and vomiting increased the chance further. Some other rare presentations include gastrointestinal symptoms, isolated vertigo, and symptoms of inner ear disease. Overdependence on radiological investigations often masks the significance of clinical examination. Ischemic stroke may appear normal in the initial 48 hours in the computed tomography scan of the brain or bony artefacts may hide the lesion. Permanent disabling deficits can follow a cerebellar stroke and the complications, which include hydrocephalus, brain stem compression, and gait abnormalities, necessitate prompt identification and management. In this review article, we aim at analysing various case reports of cerebellar infarction, the most common presentations that were under-evaluated, and their outcomes, thereby highlighting the importance of proper diagnosis and reporting of cerebellar infarction in the future. A thorough knowledge of the association between various clinical presentations of cerebellar stroke and its misdiagnosis helps clinicians to be more vigilant about the disease.

Successful combined treatment of a giant aneurysm of the posterior inferior cerebellar artery manifesting by brain stem compression

Giant aneurysms of the vertebrobasilar basin manifesting as brain stem compression are a rare pathology with an incidence ranging from 3 to 13,5 %. Surgery of such aneurysms is often associated with unsatisfactory treatment results due to the high traumatic nature of direct surgery on aneurysms of this region, as well as the close proximity of vital brain structures. Surgical intervention is also hampered by the large volume of the aneurysm, possible presence of thrombus in the sac, frequent absence of the neck, location in the anatomically difficult region, and small volume of the posterior cranial fossa (PCF). The above factors make it difficult to clip the aneurysm and increase the risk of perioperative complications. Endovascular intervention is a method of choice in most cases allowing to switch an aneurysm off the blood flow, however in the presence of mass effect aneurysm occlusion does not always achieve a clinical effect due to the preservation of brain stem compression. The aim of this publication was to demonstrate the possibility of successful combined surgical treatment of a giant aneurysm located in the PCF and accompanied by brain stem compression.

Complex Chiari Malformations: Diagnosis, Evaluation, and Treatment.

The term "complex Chiari malformation" (CCM) refers to a subset of clinical and radiographic findings that describe a subpopulation of Chiari patients with craniocervical kyphosis and secondary brainstem compression. These patients are at a greater risk for unsuccessful surgical treatment with standard Chiari surgical decompressive procedures and may require craniocervical fusion and/or odontoid resection. This article reviews concepts related to the diagnosis, management, and treatment of CCM and discusses possible directions for future research.

Management of Ventral Brainstem Compression in Chiari Malformation Type I.

Craniovertebral junction (CVJ) abnormalities are associated with the Chiari malformation type I. These abnormalities may lead to ventral brainstem compression which can be reduced with traction and posterior reduction using instrumentation. In other cases, the irreducible CVJ pathology with persistent ventral brainstem compression requires ventral decompression. In all cases, a posterior extradural or extra-intradural decompression is required along with an occipitocervical fusion to maintain the reduced and realigned CVJ or stabilize the CVJ after a ventral decompression.

Combined transnasal/transoral endoscopic odontoid resection in pediatric patients: Otolaryngologic considerations to airway management, endoscopic exposure, and complication management.

Anterior brainstem compression from odontoid pathology can occur in patients with craniocervical disorders. Occasionally, odontoid resection is required. In adults, odontoid resection has evolved toward transnasal-only endoscopic techniques. Pediatric patients, however, pose special challenges due to abnormal anatomy and smaller working spaces. A combined transnasal/transoral endoscopic odontoid resection (TN/TO EOR) can overcome this limitation. We present a case series with emphasis on otolaryngologic considerations to airway management, endoscopic approach, and management of complications. A single center, retrospective review of patients aged ≤18 undergoing combined transnasal/transoral endoscopic odontoid resection between 2011 and 2022 is presented. Clinical and surgical variables consisting of diagnosis, intubation approach, other airway procedures performed, symptoms, complications, blood loss, and time to extubation, return to oral feeding, and discharge were recorded. 19 patients aged 10.7±4.3 (range: 3-18) were included. Diagnoses included congenital syndrome (n=6), complex Chiari malformation (n=11), and congenital syndrome with Chiari (n=2). Patients commonly required indirect videolaryngoscopy for intubation, with or without fiberoptic endoscopic assistance. Seven underwent adenoidectomy, two underwent adenotonsillectomy, and one required adenoidectomy with midline palatal split and inferior turbinate outfracture. Four patients had undergone prior adenotonsillectomy. Presenting symptoms included extremity weakness (n=9), dysphagia (n=8), velopharyngeal insufficiency (n=4), sleep disturbance (n=5), and headaches (n=8). Four patients had complications, including one re-operation for residual odontoid, one flap dehiscence, one cerebrospinal fluid (CSF) leak repaired primarily, and one complicated course including temporary spinal cord injury. Blood loss was 50±43cc (median 30). Time to extubation was 1.1±2.1 days (median 0; one patient underwent tracheotomy for respiratory failure), time to oral intake was 2.9±3.7 days (median 1), and time to discharge was 7.1±7.5 days (median 4). A combined transnasal/transoral approach can be successfully used in pediatric patients to overcome difficult endoscopic access. Although complications exist, early extubation and return to oral intake occurs in the vast majority of cases. For pediatric TN/TO EOR, the otolaryngologist plays a key role in preoperative assessment, airway management, endoscopic exposure, and complication management.

Transcervical, retropharyngeal odontoidectomy - Anatomical considerations.

Anterior craniocervical junction lesions have always been a challenge for neurosurgeons. Presenting with lower cranial nerve dysfunction and symptoms of brainstem compression, decompression is often required. While posterior approaches offer indirect ventral brainstem decompression, direct decompression via odontoidectomy is necessary when they fail. The transoral and endoscopic endonasal approaches have been explored but come with their own limitations and risks. A novel retropharyngeal approach to the cervical spine has shown promising results with reduced complications. This study aims to explore the feasibility and potential advantages of the anterior retropharyngeal approach for accessing the odontoid process. To investigate the anatomical aspects of the anterior retropharyngeal approach, a paramedian skin incision was performed below the submandibular gland on two cadaveric specimens. The subcutaneous tissue followed by the platysma is dissected, and the superficial fascial layer is opened. The plane between the vascular sheath laterally and the pharyngeal structures medially is entered below the branching point of the facial vein and internal jugular vein. After reaching the prevertebral plane, further dissection cranially is done in a blunt fashion below the superior pharyngeal nerve and artery. Various anatomical aspects were highlighted during this approach. The anterior, submandibular retropharyngeal approach to the cervical spine was performed successfully on two cadavers highlighting relevant anatomical structures, including the carotid artery and the glossopharyngeal, hypoglossal, and vagus nerves. This approach offered wide exposure, avoidance of oropharyngeal contamination, and potential benefit in repairing cerebrospinal fluid fistulas. For accessing the craniocervical junction, the anterior retropharyngeal approach is a viable technique that offers many advantages. However, when employing this approach, surgeons must have adequate anatomical knowledge and technical proficiency to ensure better outcomes. Further studies are needed to enhance our anatomical variations understanding and reduce intraoperative risks.

Measurement of Deformity at the Craniovertebral Junction: Correlation of Triangular Area and Myelopathy.

Diseases of the craniovertebral junction (CVJ) are commonly associated with deformity, malalignment, and subsequent myelopathy. The misaligned CVJ might cause compression of neuronal tissues and subsequently clinical symptoms. The triangular area (TA), measured by magnetic resonance imaging/images (MRI/s), is a novel measurement for quantification of the severity of compression to the brain stem. This study aimed to assess the normal and pathological values of TA by a comparison of patients with CVJ disease to age- and sex-matched controls. Moreover, postoperative TAs were correlated with outcomes. Consecutive patients who underwent surgery for CVJ disease were included for comparison to an age- and sex-matched cohort of normal CVJ persons as controls. The demographics, perioperative information, and pre- and postoperative 2-year cervical MRIs were collected for analysis. Cervical TAs were measured and compared. A total of 201 patients, all of whom had pre- or postoperative MRI, were analyzed. The TA of the CVJ deformity group was larger than the healthy control group (1.62 ± 0.57 cm2 vs. 1.01 ± 0.18 cm2, p < 0.001). Moreover, patients who had combined anterior odontoidectomy and posterior laminectomy with fixation had the greatest reduction in the TA (1.18 ± 0.58 cm2). In CVJ deformity, the measurement of the cervical TA could indicate the severity of brain stem compression. After surgery, the TA had a varying degree of improvement, which could represent the efficacy of surgery.

Petrous Carotid to Upper Posterior Circulation Bypass for the Treatment of Basilar Trunk Aneurysm: A Novel High-Flow Intracranial-Intracranial Skull Base Bypass for Posterior Circulation.

Basilar trunk aneurysms are the most surgically challenging, and the spectrum covers small fusiform to dolichoectatic aneurysms and may lead to rupture, brain ischemia, or direct brainstem compression. The current strategy remains cerebral revascularization coupled with aneurysm trapping. Available bypass options for upper posterior circulation (UPC) are based on (1) different flow volumes from diverse blood supplies and (2) distinct modulation purposes for cerebral revascularization; however, the potential compromise of eloquent perforators of the basilar trunk and the occurrence of fatal brainstem infarcts remain unacceptable. To innovate a high-flow intracranial-intracranial skull base bypass for posterior circulation to afford robust retrograde flow and shorten the graft length. We retrospectively reviewed our experience in the treatment of a patient with basilar trunk aneurysm and reported a novel bypass alternative supplied by petrous internal carotid artery to augment blood flow to the UPC by a pretemporal approach. The postoperative course was uneventful, and there was no pons or midbrain ischemia or other complications. Postoperative computed tomography angiogram revealed the patency of bypass. There was no further development or rerupture observed during follow-up. Petrous internal carotid artery as a donor site is a reliable bypass modality for UPC. This approach provides the utmost retrograde flow to alleviate the development of dissecting aneurysms, preserves eloquent perforators of the basilar trunk, maintains bypass patency, and shortens the graft course. Therefore, this novel therapeutic alternative could be beneficial for improving the prognosis of basilar trunk aneurysms.

A deceptive mass on neonatal ultrasound and a fetal brain MRI-confirmed complex dural arteriovenous fistula postnatally: illustrative case.

Dural arteriovenous fistulas (dAVFs) are direct, aberrant connections between dural arteries and cerebral veins. In neonates, delayed diagnosis results in grim outcomes. Treatment involves endovascular management because of its success and tolerability. Here, the authors present a case of a complex dAVF initially recognized with an in utero neurosonogram and fetal magnetic resonance imaging (MRI). A 21-week fetal ultrasound of a nonspecific brain mass was confirmed with fetal MRI as a 2.7-cm T1-hyperintense posterior fossa mass. Although a large flow void in the left middle cranial fossa was present, postnatal computed tomography angiography ultimately revealed a high-flow dAVF communicating with the left transverse sinus. In the early postnatal period, the patient developed hydrocephalus. After successful partial embolization, 6-week postangiogram brain MRI indicated disease progression with the development of a venous varix causing brainstem compression. Repeat embolization resulted in complete cessation of early venous drainage. Neonatal dAVFs are exceedingly rare and result in futile outcomes; however, detection in utero is possible. Although definitive therapy must be performed postnatally, constant monitoring and early delivery can prevent complications. Attention to fetal ultrasound is essential, and knowledge of fetal MRI in the detection of these complex lesions can significantly improve outcomes.

Labyrinthitis With Negative MRI As a Precursor to Rapidly Developing Primary CNS Lymphoma of the Cerebellopontine Angle.

Few case reports have described primary central nervous system lymphoma (PCNSL) presenting as a cerebellopontine angle (CPA) lesion in HIV-positive patients. We describe a rare presentation of rapidly progressing PCNSL of the CPA/internal auditory canal (IAC) as labyrinthitis with initial negative MRI in an HIV-positive patient. A 58-year-old male with well-controlled HIV presented with sudden left sensorineural hearing loss, tinnitus, and imbalance. Vestibular testing suggested an uncompensated left peripheral vestibular weakness. MRI demonstrated facial and cochleovestibular nerve enhancement within the CPA and IAC. The presumptive diagnosis of labyrinthitis was made. Two months later, he presented to his infectious disease provider with left facial weakness and disequilibrium and was treated for presumed Bell's palsy. One month later, he presented with left corneal reflex dysfunction, decreased visual acuity, diplopia, and worsening ataxia. Repeat MRI demonstrated a new 3.6 cm lesion of the left CPA/IAC with vasogenic edema. Despite location, the mass lacked the brainstem compression characteristic of other extra-axial CPA masses such as vestibular schwannoma. Flow cytometry and cytology from cerebrospinal fluid was consistent with primary central nervous system large B-cell lymphoma. We present a unique case of rapidly progressing PCNSL of the CPA/IAC in an HIV-positive patient, presenting initially as labyrinthitis with negative MRI followed by development of multiple cranial neuropathies and 3-month repeat MRI demonstrating a large CPA mass. In HIV-positive patients with a similar initial presentation, PCNSL should considered early in the diagnostic evaluation with close clinical monitoring and a low threshold for repeat imaging.