Perioperative Segmentation of the Posterior Fossa and the Keel of Goodrich in Surgical Outcomes of Chiari Malformations.

BACKGROUND: Chiari I malformation (CM- I) is defined as the extension of brain tissue into the spinal cord. This study aimed to refine the methodology for the acquisition of 3-dimensional measurements of the posterior fossa and introduce occipital keel size as a new marker and its impact in patients with CM. MATERIALS AND METHODS: In this retrospective study, all patients who underwent Chiari decompression surgery at Montefiore Medical Center from April 2012 to April 2022 were included. Perioperative clinical information was obtained in addition to maximal keel thickness (KT), foramen magnum area, and pre-and postoperative posterior fossa volumes for each patient and age-matched controls. Volumetric measurements were obtained using AI-based semiautomated segmentation. RESULTS: A total of 107 patients with CM including 37 males, and 70 females were studied with a mean age of 26.56±17.31 compared with 103 controls without CM. The comparison between the CM and the general population groups demonstrated a significantly increased keel size in Chiari patients. Keel size had a significant relationship with dysphagia, paresthesia, and intraoperative blood loss, while posterior volume change had a significant relationship with sex and early symptomatic improvement. The Foramen magnum area was related to tonsillar descent and more prominent in patients with spina bifida. CONCLUSION: The Keel of Goodrich is a new anatomical factor that should be taken into consideration when evaluating preoperative symptoms, and intraoperative complications in patients with CM-1. Volumetric analyses demonstrated that posterior fossa volume change had a significant impact on early symptom improvement in patients with Chiari, as did the choice of operative approach. The routine use of semi-automated segmentation of the posterior fossa may help stratify Chiari patients in the future and should be implemented in routine clinical care.

Volumetric segmentation in the context of posterior fossa-related pathologies: a systematic review.

BACKGROUND: Segmentation tools continue to advance, evolving from manual contouring to deep learning. Researchers have utilized segmentation to study a myriad of posterior fossa-related conditions, such as Chiari malformation, trigeminal neuralgia, post-operative pediatric cerebellar mutism syndrome, and Crouzon syndrome. Herein, we present a summary of the current literature on segmentation of the posterior fossa. The review highlights the various segmentation techniques, and their respective strengths and weaknesses, employed along with objectives and outcomes of the various studies reported in the literature. METHODS: A literature search was conducted in PubMed, Embase, Cochrane, and Web of Science up to November 2023 for articles on segmentation techniques of posterior fossa. The two senior authors searched through databases based on the keywords of the article separately and then enrolled joint articles that met the inclusion and exclusion criteria. RESULTS: The initial search identified 2205 articles. After applying inclusion and exclusion criteria, 77 articles were selected for full-text review after screening of titles/abstracts. 52 articles were ultimately included in the review. Segmentation techniques included manual, semi-automated, and fully automated (atlas-based, convolutional neural networks). The most common pathology investigated was Chiari malformation. CONCLUSIONS: Various forms of segmentation techniques have been used to assess posterior fossa volumes/pathologies and each has its advantages and disadvantages. We discuss these nuances and summarize the current state of literature in the context of posterior fossa-associated pathologies.

STAT5b gain-of-function disease in a child with mycobacterial osteomyelitis of the skull: rare presentation of an emerging disease entity.

PURPOSE: STAT proteins play a key role in several cellular functions related to cell development, differentiation, proliferation, and survival. Persistent STAT activation due to somatic STAT5bN642H gain-of-function mutation is a rare mechanism of STAT dysregulation that results in hypereosinophilia, frequent infections, leukemias, and pulmonary diseases. Herein, we describe a case of a child with a rare early onset STAT5b gain-of-function disease treated with targeted JAK inhibition who developed a cranial Mycobacterium avium osteomyelitis. METHODS: A 3-year-old male with a known STAT5b gain-of-function mutation presented with a 10-day history of a firm, immobile, non-painful cranial mycobacterium mass with dural infiltration located anterior to the coronal suture. Stepwise management finalized with complete resection of the lesion with calvarial reconstruction. A case-based literature review was performed evaluating all patients with this mutation who developed cranial disease. RESULTS: The patient was symptom and lesion-free at 1 year since surgical resection and initiation of triple mycobacterial pharmacotherapy. Our literature review demonstrated the rarity of this disease, as well as other presentations of this disease in other patients. CONCLUSION: Patients with STAT5b gain-of-function mutations have attenuated Th1 responses and are treated with medications, such as JAK inhibitors, which further inhibit other STAT proteins that regulate immunity against rare infectious entities, such as mycobacterium. Our case highlights the importance of considering these rare infections in patients on JAK inhibitors and with STAT protein mutations. Possessing a clear mechanistic understanding of this genetic mutation, its downstream effect, and the consequences of treatment may enhance a physician's diagnostic and clinical management of similar patients in the future.

The role of venous anatomy in guiding treatment approach for dural arteriovenous fistulas of the craniocervical junction; case series & systematic review.

BACKGROUND: Dural arteriovenous fistulas (DAVF) of the craniocervical junction (CCF) are an uncommon entity with the following venous drainage pattern: inferior, superior and mixed. Patients may present with subarachnoid hemorrhage, myelopathy or brainstem dysfunction. CCJ DAVF can be treated with microsurgery or with transarterial and transvenous embolization, depending on the venous drainage pattern. We present our institutional experience of treating CCJ DAVFs along with a systematic review of the literature. METHODS: Six patients with CCJ DAVF were treated at our institution over five years. Data was collected using electronic medical record review. Systematic review was performed on CCJ DAVF using the PubMed database from 1990 to 2021. We characterized venous drainage patterns, treatment choices, and outcomes to create a classification system. RESULTS: 50 case reports, consisting of 115 patients, were included in our review. 61 (53.0 %) patients had inferior drainage while 32 (27.8 %) patients had superior drainage and 22 (19.2 %) patients had mixed venous drainage. Patients with inferior drainage had the fistulous connection at the foramen magnum while patients with superior drainage had a fistulous connection at C1-C2 (p value = 0.026). Patients with inferior drainage were more likely to present with myelopathy while patients with superior drainage presented with hemorrhage (p value = 0.000). CONCLUSIONS: Classifying the venous drainage pattern is essential in making treatment decision. Transvenous embolization works best with large superior venous drainage. If endovascular treatment is not an option, then surgical clipping can achieve successful cure. Transarterial embolization is a reasonable option in cases with a large arterial feeder.

Impact of aneurysm diameter, angulation, and device sizing on complete occlusion rates using the woven endobridge (WEB) device: Single center United States experience.

BACKGROUND: The Woven EndoBridge device is a novel treatment option for wide-necked bifurcation intracranial aneurysms (WNBA). While this device has had good results, there remains a subset of WNBA that fail this treatment. The main objective of this study is to identify risk factors that are associated with incomplete occlusion of WEB treated aneurysms at short-term follow up. METHODS: This was a retrospective study of 31 patients with intracranial aneurysms who were treated with WEB at a single institution in the USA in 2019-2021. Data was collected via chart review on patient demographics, aneurysm characteristics, procedural details, and occlusion status at six months follow up. Bivariate analyses were performed comparing completely occluded aneurysms with neck remnants and residual aneurysms. RESULTS: 16 (52%) had completely occluded aneurysms while 11 (35%) patients had a neck remnant, and 4 (13%) patients had a residual aneurysm at follow up. Patients with neck remnants and residual aneurysms had aneurysms with a larger diameter. A large aneurysm diameter is an independent risk factor for incomplete occlusion (OR 4.23 95% CI 1.08-16.53 P value = 0.038). Patients with residual aneurysms had an average difference between the aneurysm width and WEB diameter of -0.08mm compared to 1.2 mm in patients with occluded aneurysms. 75% of patients with a residual aneurysm presented with a ruptured aneurysm. Lastly, more patients with a residual aneurysm had an immediate angiographic outcome of incomplete occlusion. CONCLUSION: Larger aneurysms are at risk for incomplete occlusion status post WEB treatment. Larger, ruptured aneurysms with minimal difference in aneurysm and WEB diameter that fail to occlude immediately post-treatment are more likely to present as residual aneurysms at short-term follow up.

Identifying risk factors for perioperative thromboembolic complications in patients treated with the Woven EndoBridge device.

INTRODUCTION: Woven EndoBridge (WEB) is a new endovascular treatment option for wide necked bifurcation aneurysms. Results from the WEB-IT trial showed a 0% risk of thromboembolic complications within 30 days post-op but the rate reported in the literature is as high as 10%. We are exploring potential risk factors associated with immediate thromboembolic complications in patients treated with the WEB device. METHODS: Retrospective study of forty-two patients with intracranial aneurysms who were treated with WEB at a single center from 2019-2021. Data was collected on patient demographics, comorbidities, aneurysm characteristics, procedural details, and hospital course. Bivariate analyses were performed to compare patients who experienced a periprocedural ischemic stroke to those who did not. Multiple logistic regression modeling was performed to identify independent risk factors for thromboembolic complications. RESULTS: Of the 42 patients that were treated with WEB, 6 suffered an ischemic stroke (AIS). These patients were more likely to have an underlying diagnosis of arrythmias (p value = 0.007). Furthermore, they had a median angle of 32.0° in the true neck view on diagnostic angiogram compared to 19.5° (p value = 0.046). Lastly, they had a longer procedure length of 228 min compared to 178 min (p value = 0.002). Patients with thromboembolic complications had a longer length of stay in the hospital and worse outcomes at three months follow up. On logistic regression modeling, these risk factors did not reach statistical significance. CONCLUSION: Risk factors of thromboembolic complications after WEB placement include cardiac arrythmias, acute aneurysmal angle in the true neck view and a longer procedure length.

Imaging score for differentiation of meningioma grade.

PURPOSE: We sought to establish a comprehensive imaging score indicating the likelihood of higher WHO grade meningiomas pre-operatively. METHODS: All surgical intracranial meningioma patients at our institution between 2014 and 2018 underwent retrospective chart review. Preoperative MRI sequences were reviewed, and imaging features were included in the score based on statistical and clinical significance. Point values for each significant feature were assigned based on the beta coefficients obtained from multivariate analysis. The imaging score was calculated by adding up the points, for a total score of 0 to 5. The predictive ability of the score to identify higher-grade meningiomas was evaluated. RESULTS: Ninety patients, 50% of whom had a postoperative diagnosis of WHO grade II meningioma, were included. The mean age for the population was 59.9 years and 70% were female. Tumor volume ≥ 36.0 cc was assigned 2 points, presence of irregular tumor borders was assigned 2 points, and presence of peritumoral edema was assigned 1 point. The probability of having a WHO grade II meningioma was 0% with a score of 0, 25.0% with a score of 1, 38.5% with a score of 2, 65.4% with a score of 3, and 83.3% with a score of 4 or greater. A threshold of ≥ 3 points achieved a recall of 0.80, precision of 0.73, F1-score of 0.77, accuracy of 0.76, and AUC of 0.82. CONCLUSION: The proposed imaging scoring system had good predictive capability for WHO grade II meningiomas with good discrimination and calibration. External validation is needed.

A case of hydrocephalus confounded by suprasellar arachnoid cyst and concomitant reversible cerebral vasoconstriction syndrome.

Background: Obstructive hydrocephalus is a neurologic condition that has varied clinical and imaging presentations, as well as a multitude of congenital etiologies including aqueductal stenosis and less commonly arachnoid cysts. Aqueductal stenosis is a physical limitation to cerebrospinal fluid flow along the course of the aqueduct, which results in enlargement of the third and lateral ventricles. Arachnoid cysts are thin walled and fluid filled central nervous system lesions that can result in mass effect on adjacent structures. While arachnoid cysts are mostly asymptomatic, they may present with neurological symptoms that vary depending on the location of the lesion. Suprasellar cysts in particular may cause obstructive hydrocephalus as well as endocrine dysfunction. Reversible cerebral vasoconstriction syndrome (RCVS) is an unusual condition caused by cerebral arterial vasoconstriction that often presents initially with a thunderclap headache. Frequently, there is some environmental trigger associated with this condition. RCVS more commonly affects women and can induce stroke. Case Description: A 57-year-old female presented to the emergency department with progressive headache and visual changes. Initial workup suggested the patient's symptoms where related to RCVS but subsequent surgical management of what was presumed to be long standing, compensated hydrocephalus resulted in resolution of the patient's symptoms. Conclusion: We report, to the best of our knowledge, the first case of aquedutal stenosis and suprasellar arachnoid cyst with concomitant RCVS. The presence of multiple pathologies found on radiologic imaging illustrates the challenges presented by incidental findings and subsequent anchoring bias in medical diagnosis.

Neurological Sequelae of COVID-19.

BACKGROUND: Though primarily a pulmonary disease, Coronavirus disease 2019 (COVID-19) caused by the SARS-CoV-2 virus can generate devastating disease states that affect multiple organ systems including the central nervous system (CNS). The various neurological disorders associated with COVID-19 range in severity from mild symptoms such as headache, or myalgias to more severe symptoms such as stroke, psychosis, and anosmia. While some of the COVID-19 associated neurological complications are mild and reversible, a significant number of patients suffer from stroke. Studies have shown that COVID-19 infection triggers a wave of inflammatory cytokines that induce endothelial cell dysfunction and generate coagulopathy that increases the risk of stroke or thromboses. Inflammation of the endothelium following infection may also destabilize atherosclerotic plaque and induce thrombotic stroke. Although uncommon, there have also been reports of hemorrhagic stroke associated with COVID-19. The proposed mechanisms include a blood pressure increase caused by infection leading to a reduction in angiotensin converting enzyme-2 (ACE-2) levels that results in an imbalance of the renin-angiotensin system ultimately manifesting inflammation and vasoconstriction. Coagulopathy, as demonstrated by elevated prothrombin time (PT), has also been posited as a factor contributing to hemorrhagics stroke in patients with COVID-19. Other neurological conditions associated with COVID-19 include encephalopathy, anosmia, encephalitis, psychosis, brain fog, headache, depression, and anxiety. Though there are several hypotheses reported in the literature, a unifying pathophysiological mechanism of many of these disorders remains unclear. Pulmonary dysfunction leading to poor oxygenation of the brain may explain encephalopathy and other disorders in COVID-19 patients. Alternatively, a direct invasion of the CNS by the virus or breach of the blood-brain barrier by the systemic cytokines released during infection may be responsible for these conditions. Notwithstanding, the relationship between the inflammatory cytokine levels and conditions such as depression and anxiety is contradictory and perhaps the social isolation during the pandemic may in part be a contributing factor to some of the reported CNS disorders. OBJECTIVE: In this article, we review the current literature pertaining to some of the most significant and common neurological disorders such as ischemic and hemorrhagic stroke, encephalopathy, encephalitis, brain fog, Long COVID, headache, Guillain-Barre syndrome, depression, anxiety, and sleep disorders in the setting of COVID-19. We summarize some of the most relevant literature to provide a better understanding of the mechanistic details regarding these disorders in order to help physicians monitor and treat patients for significant COVID-19 associated neurologic impairments. METHODS: A literature review was carried out by the authors using PubMed with the search terms "COVID-19" and "Neurology", "Neurological Manifestations", "Neuropsychiatric Manifestations", "Stroke", "Encephalopathy", "Headache", "Guillain-Barre syndrome", "Depression", "Anxiety", "Encephalitis", "Seizure", "Spasm", and "ICUAW". Another search was carried out for "Long-COVID" and "Post-Acute COVID-19" and "Neurological Manifestations" or "Neuropsychiatric Manifestations". Articles such as case reports, case series, and cohort studies were included as references. No language restrictions were enforced. In the case of anxiety and depression, attempts were made to focus mainly on articles describing these conditions in infected patients. RESULTS: A total of 112 articles were reviewed. The incidence, clinical outcomes, and pathophysiology of selected neurological disorders are discussed below. Given the recent advent of this disease, the incidence of certain neurologic sequelae was not always available. Putative mechanisms for each condition in the setting of COVID-19 are outlined.

Nuances in detecting retained foreign bodies: a case report of a glass shard embedded in a child's scalp.

Foreign bodies (FBs) are a relatively common reason for admission to the emergency department, with subacutely embedded FBs presenting a diagnostic challenge to physicians. Retained FBs may cause the patient harm and result in litigation when missed. Diagnostic imaging is a powerful tool for localization of FBs and a physician's choice of modality should reflect its anticipated composition. This case report pertains to a 2-year-old boy with a glass shard embedded in his retro auricular scalp who presented with a painful subcutaneous lesion months after an overlying laceration repair at an outside emergency room. The attending neurosurgeon was able to identify a glass shard both on physical examination and axial T2-weighted MRI. Surgical exploration resulted in the removal of a 1-cm square glass shard. Key to the diagnostic potential of imaging is knowledge of a patient's relevant medical history and the composition of the suspected FB. Herein, we describe imaging modalities and their utility in the context of retained glass FBs.