Lethal mycotic pseudoaneurysm presenting as isolated sixth nerve palsy.

Pseudoaneurysm of the internal carotid artery caused by skull base osteomyelitis (SBO) is a lethal condition seen in immunocompromised patients, predominantly those with diabetes mellitus. Cranial nerve involvement is a common complication and generally indicates a poor prognosis. We report the case of a 62-year-old diabetic patient who presented with isolated sixth cranial nerve palsy. She had uncontrolled blood sugar levels and high erythrocyte sedimentation rate, and she suffered from pyelonephritis. Neuroimaging detected SBO with multiple secondary mycotic pseudoaneurysms prominent at the petrocavernous junction. Ischemia is the most common etiology for an isolated abducens nerve palsy, but in certain cases neuroimaging is warranted to prevent life-threatening complications. This case highlights the importance and urgency of identifying and managing such conditions.

Role of advanced (magnetic resonance) neuroimaging and clinical outcomes in neonatal strokes: Experience from tertiary care center.

Neonatal strokes constitute a major cause of pediatric mortality and morbidity. Neuroimaging helps in its diagnosis as well as prognostication. However, advanced imaging, including magnetic resonance imaging (MRI), carries multiple challenges. Limited data exists in the literature on imaging-based predictors of neurological outcomes in neonatal stroke in the Indian population. In this study, we reviewed our available data on neonatal stroke patients between 2015 and 2020 for clinico-radiological patterns. During this period, 17 neonatal strokes were admitted and the majority were term births with a slight male preponderance. Seizures and encephalopathy were the most common presentation. Multiple maternal risk factors such as gestational diabetes, meconium-stained liquor, APLA syndrome, fever, deranged coagulation profile, oligohydramnios, cord prolapse, and non-progressive labor were seen. Cardiac abnormalities were seen in only less than half of these patients with the most common finding being atrial septal defects (ASD). Transcranial ultrasound was performed in eight neonates and the pick-up rate of ultrasound was poor. MR imaging showed large infarcts in 11 patients. The MCA territory was most commonly involved. Interestingly, five neonates had venous thrombosis with three showing it in addition to arterial thrombosis. Associated ictal, as well as Wallerian changes, were noted in 10. Although large territorial infarcts were the most common pattern, non-contrast MR angiography did not show major vessel occlusion in these cases. Outcomes were fairly good and only three patients had a residual motor deficit at 1 year. No recurrence of stroke was seen in any of the neonates.

Understanding ASPECTS of stroke: Inter-rater reliability between emergency medicine physician and radiologist in a rural setup.

PURPOSE: The purpose is to determine the inter-rater reliability in grading ASPECTS score, between emergency medicine physician at first contact and radiologist among patients with acute ischemic stroke. MATERIALS AND METHODS: We conducted a prospective analysis of 765 acute ischemic stroke cases referred to the Department of Radiodiagnosis in a rural-based hospital in South India, during January 2017 to October 2021. Non-contrast computed tomography (NCCT) scans of the brain were performed using GE Bright Speed Elite 128 Slice CT Scanner. ASPECTS score was calculated separately by an emergency medicine physician and radiologist. Inter-rater reliability for total and dichotomized ASPECTS (≥6 and <6) scores were assessed using statistical analysis (ICC and Cohen ĸ coefficients) on SPSS software (v17.0). RESULTS: Inter-rater agreement for total and dichotomized ASPECTS was substantial (ICC 0.79 and Cohen ĸ 0.68) between the emergency physician and the radiologist. Mean difference in ASPECTS between the two readers was only 0.15 with standard deviation of 1.58. No proportionality bias was detected. The Bland-Altman plot was constructed to demonstrate the distribution of ASPECTS differences between the two readers. CONCLUSION: Substantial inter-rater agreement was noted in grading ASPECTS between emergency medicine physician at first contact and radiologist, thereby confirming its robustness even in a rural setting.

Cardiac phoenix in the brain-occult intracranial hemorrhagic metastases from completely resected atrial myxoma.

BACKGROUND: Cardiac myxomas are sporadic in nature and can often recur with a frequency of 3%, especially in middle-aged women, and 22% of the cases account to a part of Carney complex. Complete surgical removal of the myxoma is usually curative. Recurrence has been related with partial surgical excision, multicentricity, and embolism of tumor fragments. CASE DESCRIPTION: We report a case of a patient with single brain metastases due to tumor embolization, from a cardiac myxoma operated prior. This case is exclusive, as tumor embolization from atrial myxoma to the cerebral cortex can be possible, within a short duration. In our case, the patient was evaluated with a magnetic resonance imaging brain and a solitary hemorrhagic lesion in the eloquent cerebral cortex was observed. To determine the primary etiology, the diagnosis of probable metastases was thought of, and a thorough workup was planned. Surprisingly, no primary lesion was detected, and as a histological diagnosis was required, he underwent a navigation-guided excisional biopsy of lesion. The biopsy was indicative of a metastatic deposit from an atrial myxoma. CONCLUSION: In eloquent cortex lesions, gross total resection is challenging for a neurosurgeon especially when the patient has no significant neurological deficits. Timely gross total resection of a solitary metastatic lesion can improve the patient's outcome and can enhance early recovery with less or no morbidity.

Clinical utility of visualisation of nigrosome-1 in patients with Parkinson's disease.

OBJECTIVE: To determine the diagnostic characteristics of poor visualisation of nigrosome-1 as a neuroimaging biomarker in Parkinson's disease (PD) and to explore the relationship of poor visualisation of nigrosome-1 and clinical asymmetry. METHODS: High-resolution gradient-echo sequences of 67 patients with PD and 63 healthy controls were reviewed by two radiologists blinded to the clinical details. A three-tier classification system was used to categorise the scans based on the visualisation of nigrosome-1, and inter-rater reliability was calculated at each level of classification. Other diagnostic properties such as sensitivity, specificity and predictive values were calculated. The relationship between poor visualisation of nigrosome-1 and clinical asymmetry was also assessed. RESULTS: Poor visualisation of nigrosome-1 had high sensitivity (98.5%), specificity (93.6%), positive-predictive value (94.3%), negative-predictive value (98.3%), accuracy (96%) and inter-rater reliability (k = 0.75-0.92). Poorly visualised nigrosome-1 was significantly associated with higher motor asymmetry in the contralateral side in 64.8% of subjects (p = 0.004). CONCLUSIONS: Poor visualisation of nigrosome-1 in PD had good diagnostic properties as a neuroimaging biomarker in PD. There was also a significant agreement on clinical asymmetry and poor visualisation of nigrosome-1. KEY POINTS: • Nigrosome-1 represents the largest collection of dopaminergic neurons in dorso-lateral substantia nigra. • Loss of nigrosome-1 is being studied as a biomarker in Parkinson's disease. • Visualisation of nigrosome-1 had good diagnostic properties as a biomarker. • There was a contralateral relationship between nigrosome-1 lateralisation and clinical asymmetry. • We also highlight the potential limitations of nigrosome-1 visualisation as a biomarker.

Precipitating hydrophobic injectable liquid embolization of intracranial vascular shunts: initial experience and technical note.

Precipitating hydrophobic injectable liquid is a new liquid embolic agent used mainly for intracranial neurointervention. The agent is ready to use (no shaking is required), since iodine, the radiopaque material, is covalently bonded into the compound. Additionally, due to the absence of tantalum, minimal artifacts are seen on postprocedure follow-up CT scans, and the agent penetrates into vessels smaller than 10 µm. The authors report their initial experience with the use of this agent in neurovascular intervention.

Headache in cerebral venous sinus thrombosis revisited: Exploring the role of vascular congestion and cortical vein thrombosis.

Background and purpose Headache constitutes the most common symptom of cerebral venous sinus thrombosis (CVST), but its pathophysiology is unclear. We sought to investigate the potential mechanism for headache genesis in patients with CVST based on its imaging correlates. Methods A subgroup of CVST patients having headache as the predominant symptom without significant parenchymal lesion were retrospectively analysed for imaging features of vascular congestion (VC), in addition to cortical venous (CVT) and dural sinus thrombosis (DST) on magnetic resonance imaging. Headache and imaging patterns were classified into lateralized and nonlateralized phenotypes and their correlation was sought. Results Among 41 patients included, 28 had lateralized headache (LH group; 15 males; mean age 32.25 ± 9.19 years) while 13 had nonlateralized headache (non-LH group; six males; mean age 27.15 ± 8.65 years). Headache characteristics in both the groups were quite similar. Imaging showed VC in 39 of 41 and CVT among 35 of 41 patients, which were lateralized in 23 of 39 and 18 of 35 patients, respectively. Nearly all lateralized imaging patterns (21 of 23 for VC and 17 of 18 for CVT) occurred in the LH group and ipsilateral to (concordant) headache, while the non-LH group showed lateralized VC and CVT in only two and one patient respectively. Sinus thrombosis was lateralized in both groups irrespective of headache laterality. Whole cohort headache-imaging laterality (including patients with nonlateralized headache and nonlateralized imaging) concordance was 31 of 39, 24 of 35 and 18 of 41 for vascular congestion, cortical vein thrombosis and dural sinus thrombosis respectively. Conclusion Co-localization of VC and CVT with overlying headache might provide a possible explanation of headache and its laterality in patients with CVST.