Inferior Division Research Articles

Abstract 250: Early Revascularization in Cervical Artery Dissection: Case Studies of Improved Neurological Outcomes

Introduction Cervical artery dissection (CAD) involves a tear in the inner lining of the carotid or vertebral artery, contributing to up to 25% of ischemic strokes in individuals under 50 years of age. This condition can lead to the formation of a false lumen within the vessel wall, potentially causing intraluminal thrombus, vessel stenosis, or pseudoaneurysm, ultimately leading to cerebral ischemia. Endovascular therapy is an option for recurrent cerebrovascular events, dissecting aneurysms, and severe stenosis, as well as in cases where anticoagulation is not tolerated. Here, we describe two cases of left internal carotid artery dissections that required revascularization due to recurrent episodes of reduced blood supply or distal embolism. Methods Electronical medical records review. Results Case 1: A 39‐year‐old man with a history of hypertension, hyperlipidemia, and migraine presented with traumatic bilateral carotid stenosis due to dissection after a fall. Initially discharged on antiplatelet agents and returned with TIA symptoms of left hemispheric hypoperfusion followed by a small left MCA stroke. Catheter angiography revealed cervical ICA dissection with a false and true lumen, along with a 99% distal cervical carotid stenosis and trace distal flow. Revascularization was performed by crossing the stenosis with an Aristotle 14 wire for good distal access. Subsequently, the Spider device was deployed in the petrous internal carotid, and Xact stents (8times6x40mm and 9times7x40mm) were placed across the distal and proximal portion of the stenosis. Post‐intervention, the patient was started on Eptifibatide infusion for 4 hours, followed by DAPT and Apixaban upon discharge. At the 30‐day follow‐up, the patient had a modified Rankin Scale (mRS) score of 0 and repeated carotid Doppler ultrasonography (CDUS) showed a patent stent. Case 2 A 36‐year‐old female with a history of hyperlipidemia, depression, and hypertension presented as a level 1 code stroke for aphasia and right hemiplegia. On arrival, her NIHSS was 9. CTA head and neck revealed a left ICA occlusion caused by dissection with reconstitution and occlusion of the left MCA inferior division. Catheter angiography revealed a left ICA occlusion due to dissection with a true and false lumen and distal reconstitution of the vessel. The diagnostic catheter and base catheter were advanced past the dissection, and a thrombectomy was performed using an Aristotle 14 wire catheter with aspiration and a stent retriever with TICI 2b reperfusion. Following this, the catheter was retracted to the cervical carotid, and the Walrus balloon was inflated, followed by the deployment of Xact stents (8times6x40mm and 9times7x40mm). Post‐intervention, the patient was started on Aspirin and Ticagrelor. Subsequent MRI of the brain and MRA showed a left MCA stroke with occlusion of the stent, which CDUS confirmed. Despite this, on discharge, the patient had mixed aphasia and RSW (3/5 strength). At 30 days, the patient had mild expressive aphasia with a mRS of 2, which improved to a mRS of 1 at 90 days. Conclusion These cases illustrate examples of select situations where early revascularization intervention can improve neurological outcomes under specific conditions. Additional studies are required.

Mechanical Thrombectomy in Medium Vessels Occlusion (MeVOs): An Institutional Experience with M2 Divisions of Middle Cerebral Artery.

Mechanical thrombectomy has been established as a safe, standard and effective treatment option for occlusions of the proximal segment of the middle cerebral artery (MCA), as demonstrated in numerous studies. However, performing thrombectomy in the M2 divisions of MCA presents inherent challenges. In this institutional experience, we aim to delineate the recanalisation rates achieved through mechanical thrombectomy in cases involving the M2 segment of the MCA. We conducted a retrospective analysis of patients who underwent thrombectomy due to M2 MCA occlusions in the period from January 2018 to December 2021. Various factors affecting recanalisation rates were assessed. A total of 15 patients with M2 segment occlusions of the middle cerebral artery were included in the study, comprising 11 in the superior division and 4 in the inferior division. The successful recanalisation rate was 72.33%, with notably higher success observed in cases of inferior division occlusion. The primary outcome of our study was the mTICI recanalisation status, categorised as successful recanalisation (mTICI = 2b or mTICI = 3) and unsuccessful recanalisation (mTICI = 1 or mTICI = 2a) and mRS at 6 months. None of the predictors assessed reached statistical significance. Mechanical thrombectomy demonstrates favourable efficacy and recanalisation rates in cases of M2 MCA division occlusion. Notably, inferior division occlusions exhibit a higher likelihood of successful recanalisation.

Functional connectivity in autism spectrum disorder evaluated using rs-fMRI and DKI.

We evaluated functional connectivity (FC) in patients with adult autism spectrum disorder (ASD) using resting-state functional MRI (rs-fMRI) and diffusion kurtosis imaging (DKI). We acquired rs-fMRI data from 33 individuals with ASD and 33 healthy controls (HC) and DKI data from 18 individuals with ASD and 17 HC. ASD showed attenuated FC between the right frontal pole (FP) and the bilateral temporal fusiform cortex (TFusC) and enhanced FC between the right thalamus and the bilateral inferior division of lateral occipital cortex, and between the cerebellar vermis and the right occipital fusiform gyrus (OFusG) and the right lingual gyrus, compared with HC. ASD demonstrated increased axial kurtosis (AK) and mean kurtosis (MK) in white matter (WM) tracts, including the right anterior corona radiata (ACR), forceps minor (FM), and right superior longitudinal fasciculus (SLF). In ASD, there was also a significant negative correlation between MK and FC between the cerebellar vermis and the right OFusG in the corpus callosum, FM, right SLF and right ACR. Increased DKI metrics might represent neuroinflammation, increased complexity, or disrupted WM tissue integrity that alters long-distance connectivity. Nonetheless, protective or compensating adaptations of inflammation might lead to more abundant glial cells and cytokine activation effectively alleviating the degeneration of neurons, resulting in increased complexity. FC abnormality in ASD observed in rs-fMRI may be attributed to microstructural alterations of the commissural and long-range association tracts in WM as indicated by DKI.

Management of Vestibular Schwannoma

Background Vestibular schwannoma (VS) is considered histologically a benign tumor and is currently preferred over the older term (Acoustic neuroma) as it usually arises from the inferior division of the vestibular nerve and not the acoustic nerve in the cerebellopontine angle. VS were one of the most common intra cranial tumors, comprising 8-10% of tumors in most series. Annual incidence is probably about 1.5 cases per 100,000 population, over the past couple decades this estimate has increased and the typical size at the initial diagnosis has decreased as a result of the advances in the MRI scans & CT scan qualities, (VS) is found to be occurring among middle age groups with no gender prevalence in the fourth or fifth decade. Aim of the Work To evaluate the VS management especially partial resection of large VS followed by gamma knife. Patients and Methods This study is a retrospective prospective study. This study was carried out at Al-Demerdash University hospital, the authority of specialized institutes and teaching hospitals and international medical Centre (Gamma knife department). Time of the study: from March 2019 till March 2021. Results In this study we found that according to the demographic, characteristics & personal history of the study group, it is noted that vestibular shwannoma is common among middle aged group (mean =41 years), with no substantial difference between genders (53% F & 47% M), we found that as regard the clinical picture, most of patients suffered from hearing loss as a complaint (88%) of about 3.5 months duration (median IQR) while all the patients (100%) had a sensory neural sensory loss and verified by PTA, SDT & word discrimination, tinnitus & unsteadiness were found in 70% & 50% respectively. This study has some limitations which are small populations of patients with vestibular schwannoma who generally have short follow-up. We include patients with heterogeneous tumors in regard to size and hearing status. Further studies needed with large populations to establish our results. Conclusion We concluded that considering the good tumor growth control and facial nerve function preservation as well as the possibility of preserving serviceable hearing and the low number of complications, subtotal resection followed by Gamma knife can be the treatment option of choice for large Vestibular schwannoma.

Deep Inferior Epigastric Perforators Topography for "Island Transverse Rectus Abdominis Musculocutaneous Flap" in Breast Reconstruction.

Background The Island transverse rectus abdominis musculocutaneous (TRAM) flap is well vascularized with very reliable blood flow, because all perforators of the zone I are included when it is harvested. The number of perforators, topographic mapping, and their relationship with reconstructed outcomes were investigated. Methods Fifty patients with Island TRAM breast reconstruction from September 2021 to August 2022 were investigated. The zone I was divided into a total of eight sections. Under the loupe magnification, all perforators larger than 0.5 mm in zone I were counted with fine dissection, and photographs were taken in background of vessel loops. Complications like flap necrosis, seroma, and hematoma were also investigated. Result There are 12 ideal perforators on average in zone I such as one perforator in section I, II, IV, V, VI, VIII, and three perforators in section III and VII. However, two perforators (M6 and L6) below arcuate line were sacrificed in the time of flap harvest to prevent hernia. Island TRAM included 10 perforators on average (5 perforators in each side) above arcuate line to be transferred to the recipient site. Only minor complications were identified. Conclusion The Island TRAM flap includes 10 perforators to get the vigorous blood flow. The periumbilical to upper medial perforators become more dominant in the perfusion of the flap after deep inferior epigastric artery division. Well preserved perforators will guarantee the satisfactory breast reconstruction with the least complication.

Association of inferior division MCA stroke location with populations with atrial fibrillation incidence

Background and Aim: Considering the anatomical features of Middle Cerebral Artery (MCA) bifurcation, larger emboli are more likely to enter the inferior division over the superior division. Since emboli of cardiac origin are larger on average than emboli of arterial origin, we hypothesize that the infarcts in temporal and parietal lobes are more likely associated to atrial fibrillation than those in the frontal lobes, therefore occurring more often in populations with higher incidence of atrial fibrillation, such as male (compared to women) and white (compared to black) patients.Methods: We included 197 patients with MCA “temporoparietal predominant” infarcts and 105 with “frontal predominant” infarcts. Variations between stroke location (frontal or temporoparietal), sex, and race were examined via Chi-square test.Results: Male patients were more likely than female patients to be afflicted by temporoparietal strokes versus frontal strokes, while white patients had greater likelihood than black patients to be afflicted by temporoparietal strokes versus frontal strokes. Patients with confirmed diagnosis of atrial fibrillation display more temporoparietal strokes compared to frontal strokes.Conclusion: Temporoparietal MCA ischemic strokes occur more frequently in male and white patients: populations with known increased incidence of atrial fibrillation. In addition, population-specific anatomical characteristics of the MCA bifurcation might favor the larger cardiac emboli to enter the inferior division and cause temporoparietal infarcts. This association can help guide search for the most likely etiology of infarcts.

Abstract Number ‐ 227: Retrograde embolism from a Subclavian Thrombus causing Acute Ischemic Stroke in the Middle Cerebral Artery

Introduction Intracranial embolism to the middle cerebral artery usually occurs because of embolization from the heart, carotid artery or the aorta. Here we describe a case of a subclavian thrombus, embolizing to the middle cerebral artery. Retrograde embolism is a rarely described mechanism of acute ischemic stroke. Methods A 49‐year‐old gentleman with a history of hyperlipidemia, peripheral artery disease, smoking, prior stroke, previously treated arteriovenous malformation (AVM) in the left parieto‐occipital region and active methamphetamine use presented with sudden onset dysarthria and left facial weakness (NIH stroke scale–3). CT angiogram (CTA) head and neck demonstrated a right M2 inferior division occlusion and noted nonocclusive thrombus attached to right subclavian artery atherosclerotic plaque, proximal to the origin of the right vertebral artery and otherwise minimal extracranial, and intracranial atherosclerotic disease. He was not a candidate for IV thrombolysis due to his AVM, or mechanical thrombectomy (MT) due to low NIHSS. Apixaban was started. Trans‐esophageal echocardiogram (TEE) demonstrated a grade 2 PFO. Venous doppler ultrasound performed of his upper and lower extremities was negative. On day 2 of hospitalization, his left hemiparesis and dysarthria worsened. Repeat CTA head and neck showed absence of the right subclavian thrombus and new distal M1‐MCA thrombus, suggestive of retrograde embolism from the right subclavian artery. The patient was started on IV heparin and aspirin. A stroke in young work‐up was sent including antinuclear antibodies (ANA), antineutrophil cytoplasmic antibodies (ANCA), homocysteine, hexagonal phase phospho proteins, antiphospholipid antibodies, HIV, rheumatoid factor, cryoglobulin, hepatitis B antibodies, hepatitis C antibodies, sickle cell screen, Sjogren’s syndrome antibodies, drug screen, and was negative. Results Embolism (cardioembolism and artery–artery embolism) to the intracranial vasculature is an important cause of acute ischemic stroke. Retrograde embolization is rarely described as a cause of ischemic stroke. Our patient presented initially with distal right M2 occlusion and subocclusive thrombus of the right subclavian artery, associated with focal atherosclerosis but otherwise patent extracranial and intracranial cerebral vessels. Work‐up including transesophageal echocardiogram, and hypercoagulable work‐up was unrevealing. Repeat CT angiogram obtained in view of worsening deficits revealed absence of his right subclavian thrombus and new distal M1‐MCA occlusion presumed retrograde embolism from the right subclavian artery. This is may represent the consequence of local turbulence and retrograde flow during diastole. Conclusions When considering sources of embolic stroke, retrograde embolism should be considered in patients with focal atherosclerosis.

Inferior pulmonary ligament division during left upper lobectomy causes pulmonary dysfunction.

The division of inferior pulmonary ligament (IPL) during upper lobectomy (UL) was believed to be mandatory to dilate the remaining lung sufficiently. However, the benefits, especially postoperative pulmonary function, remain controversial. This study aimed to evaluate whether IPL division leads to pulmonary dysfunction. This retrospective study included 213 patients who underwent UL between 2005 and 2018. They were categorized into an IPL division group (D group, n = 106) and a preservation group (P group, n = 107). Postoperative dead space at the lung apex, pulmonary function and complications were assessed using chest X-rays and spirometry. Changes in bronchial angle, cross-sectional area and circumference of the narrowed bronchus on the excised side were measured on three-dimensional computed tomography. There was no significant difference in the postoperative complication rate, the dead space area, forced vital capacity (FVC), or forced expiratory volume in 1 s (FEV1) between the 2 groups after right UL (FVC; P = 0.838, FEV1; P = 0.693). By contrast, after left UL pulmonary function was significantly better in the P than in the D group (FVC; P = 0.038, FEV1; P = 0.027). Changes in bronchial angle did not significantly differ between the 2 groups. The narrowed bronchus's cross-sectional area (P = 0.021) and circumference (P = 0.009) were significantly smaller in the D group than in the P group after left UL. IPL division during left UL caused postoperative pulmonary dysfunction and airflow limitation due to bronchial kinking. IPL preservation may have a beneficial impact on postoperative pulmonary function.

M1, M2: Time to Bid Adieu!

M1, M2: Time to Bid Adieu!

Does the Stent Retriever Placement in the Division of Middle Cerebral Artery Affect the Recanalization Success in M1 Occlusions?

The location of arterial occlusions can be predictive in the prognosis and endovascular treatment of acute stroke patients. We aimed to determine if the location of the stent retriever being on the superior or inferior division of the middle cerebral artery has an effect on the success and clinical outcomes of recanalization in middle cerebral artery M1 occlusion. Data were generated for the period from May 2015 to January 2019. Divisions of middle cerebral artery were assigned to the 2 groups as superior and inferior divisions according to the anatomical classification. The dominant trunk of the artery was assessed on the last angiogram image. We eventually included 81/90 patients (mean age: 62 ± 13.5; 63% [51/81] female; mean National Institutes of Health Stroke Scale rating: 16.3 ± 3.6) treated with thrombectomy. The branches of the middle cerebral artery were as follows: 40 (49.4%) co-dominant, 22 (27.2%) inferior, and 19 (23.5%) superior division dominant. The stent retriever was placed in the dominant trunk in 22/41(53.7%) cases at first pass. When stent retriever was placed in the dominant middle cerebral artery trunk, the rate of successful recanalization was very high with the first pass of thrombectomy (P < .001). Stent retriever placement within the superior or inferior middle cerebral artery trunk does not have an effect on the success rate of recanalization; however, its placement in the dominant trunk can increase the chance of complete recanalization to be early.

The impact of dissection of station 9 on survival and the necessity of pulmonary ligament division during upper lobectomy for lung cancer

Background We conducted this study to investigate the need for dissection of station 9 lymph nodes during upper lobectomy for non-small-cell lung cancer (NSCLC) and to find out the operative results of inferior pulmonary ligament division. Methods A total of 840 patients who underwent upper lobectomy for NSCLC between January 2007 and June 2020 were evaluated retrospectively. The patients were separated into two groups – those having undergone lymph node dissection of station 9 and inferior pulmonary ligament dissection (Group I) and those who did not (Group II). In these groups, the prognostic value of station 9 lymph nodes and postoperative effects (drainage time, prolonged air leak, dead space and length of hospital stay) of ligament division or preservation were analyzed. Results The number of patients with station 9 lymph node metastasis was only one (0.1%) and that was multi-station pN2 disease. Station 9 lymph nodes were found in 675 (80.4%) patients, while 22 (2.6%) patients had no lymph nodes in the dissected material. In the other 143 (17%) patients, the inferior pulmonary ligament and station 9 were not dissected. While 5-year survival was 64.9% in 697 patients of Group I, it was 61.3% in 143 patients of Group II (p = 0.56). There was no statistically significant difference between the groups in postoperative effects of ligament division or preservation. Conclusions In upper lobectomies, status of station 9 does not have a significant impact on patients' survival and lymph node staging. Additionally, preservation or division of the inferior pulmonary ligament has no significant advantage or disadvantage.

Intracranial Stenting: Angioplasty Basic Technique, Indications, and Sizing: 2-Dimensional Operative Video.

Intracranial atherosclerotic disease (ICAD) is a common cause of stroke. Antiplatelet therapy is the mainstay for symptomatic ICAD treatment. Endovascular management with submaximal angioplasty and/or intracranial stenting is reserved for patients with repeated ischemic events despite optimal medical therapy. We demonstrate intracranial angioplasty and stenting technique, technique indications, and sizing of stent and target vessel diameter. Stenting and angioplasty have been described in the Stenting and Aggressive Medical Management for Preventing Recurrent Stroke in Intracranial Stenosis and Wingspan Stent System Post Market Surveillance trials.1,2 Submaximal angioplasty has also been described.3 This patient, who had been on dual antiplatelet therapy for several months, initially presented with occlusion of the left middle cerebral artery M2 inferior division and underwent mechanical thrombectomy with successful reperfusion. Postoperatively, the patient's symptoms did not improve. Medical management was optimized with heparin infusion. However, repeat stroke study demonstrated M2 inferior division reocclusion. A decision was made to proceed with intracranial angioplasty and stenting. P2Y12 levels were therapeutic. Under moderate conscious sedation, submaximal angioplasty of up to 80% of the normal M2 caliber was attempted. However, we observed persistent high-grade stenosis of the M2 inferior division. The major risk of crossing the lesion for angioplasty is vessel perforation. To safely perform this maneuver, we used a J-configured Synchro-2 microwire (Stryker). Because of the patient's recent thrombectomy, we also had prior tactile feedback about how much resistance was encountered while crossing the occlusion. We then deployed a balloon-mounted intracranial stent for optimal radial force across the stenotic area to restore perfusion. Postoperative computed tomography perfusion showed resolution of the previously noticed perfusion deficit. The patient gave informed consent for the procedures and video recording. Institutional review board approval was deemed unnecessary. Video. ©University at Buffalo Neurosurgery, September 2020. With permission.

Lateral Medullary Syndrome in a patient with Covid 19 disease

A 68 years old male diabetic patient presented to the Emergency Departmentwith chief complaints of slurring of speech and weakness in the left lower limb for 1 day. The patient was also experiencing respiratory symptoms from the last 4-5 days, cough, and dyspnea. On arrival in the emergency department, the patient was pyrexial. Covid-19 rapid antigen test was done was comes to positive. The patient was shifted to covid ICU, a Covid RT PCR sample was sent, and an MRI stroke protocol was planned. MRI BRAIN was suggestive of right-sided lateral medullary infarcts. Right vertebral artery flow void absent. MR ANGIO BRAIN- Eccentric short segment plaque involving the proximal segment of the left subclavian. Eccentric plaques involving the posterior aspect of left proximal ICA left petrous ICA and both cavernous ICA. Lack of flow-related enhancement in right vertebral artery! occluded. Nonvisualized inferior division of right MCA. Keywords: Lateral Medullary Syndrome; Covid 19 disease.

Diabetic Oculomotor Nerve Palsy Displaying Enhancement of the Oculomotor Nerve in the Orbit and Cavernous Sinus on MRI

Introduction: Imaging data were scarce on diabetic oculomotor nerve palsy (ONP). Our study explored the MRI features and their clinical implications for diabetic ONP. Methods: Fifty-nine patients with a clinical diagnosis of diabetic ONP were recruited from our department between January 2015 and December 2019. Orbital MRI was retrospectively analyzed, and follow-up scans were obtained for 5 patients. Based on the ocular motor nerve palsy scale, the difference in the scores on the first and last hospital days was defined as the improvement score and was used to assess the treatment effects in all. Results: Thirty-eight (64.41%) patients presented thickening and enhancement of the cavernous segment and inferior division of the intraorbital segment of the ipsilateral oculomotor nerve, with the cisternal segment spared in all. After complete resolution of symptoms, follow-up MRI in 5 patients revealed that the enhancement was less obvious compared with the previous images. 6 patients in the enhancement group and 4 patients in the nonenhancement group were treated with 80 mg of methylprednisolone. Significant differences were not detected in the median improvement scores between patients with and those without corticosteroid use (p = 0.240). Conclusion: Thickening and enhancement of the unilateral oculomotor nerve were common imaging findings in diabetic ONP, and they persisted after complete resolution of symptoms in some patients. The cavernous segment and the inferior division of the intraorbital segment were simultaneously involved, and the cisternal segment was often spared. Refraining from corticosteroids was recommended even with nerve enhancement.

Congenital abducens-oculomotor dysinnervation

In a boy aged 6 years left unilateral congenital ptosis with medial rectus-levator palpebrae superioris (MR-LPS) synkinesis; the coexisting hitherto unreported likely lateral rectus-superior rectus (LR-SR) dysinnervation is reported. Ocular movements were full and cover test did not reveal any ocular misalignment. Such a presentation can only arise from two concurrent dysinnervations: first one between inferior and superior divisions of third nerve and second one between third and sixth cranial nerve. The dysinnervation may conform to a forme-fruste TUBB3 (Tubulin, Beta 3 Class III Gene) pathogenic variant phenotype and may be classed as a novel congenital cranial dysinnervation disorder (CCDD).

Effective Connectivity Extracted from Resting-State fMRI Images Using Transfer Entropy

Background and objectiveBased on magnetic resonance imaging (MRI), macroscopic structural and functional connectivity of human brain has been widely explored in the last decade. However, little work has been done on effective connectivity between individual brain parcels. In this preliminary study, we aim to investigate whole-brain effective connectivity networks from resting-state functional MRI (rs-fMRI) images. Material and methodsAfter the functional connectivity networks of 26 healthy subjects (aged from 25 to 35 years old) from Human Connectome Project database were derived from rs-fMRI images with dynamic time warping, proportional thresholding (PT) was performed on the functional connectivity matrices by retaining the PT% strongest functional connections. PT% ranges from 40% to 10% in steps of 5%. Then, effective connections corresponding to the PT% strongest functional connections, both bi-directional and unidirectional, were estimated with Renyi's 2-order transfer entropy (TE) method. Topological metrics of the built functional and effective connectivity networks were further characterized, including clustering coefficient, transitivity, and modularity. ResultsIt is found that the effective connectivity networks exhibit small world attributes, and that the networks contain a subset of highly interactive regions, including right frontal pole (in-degree 6), left middle frontal gyrus (in-degree 8, out-degree 1), right precentral gyrus (out-degree 9), left precentral gyrus (out-degree 7), right posterior division of supramarginal gyrus (in-degree 2, out-degree 3), left angular gyrus (out-degree 6), left inferior division of lateral occipital cortex (out-degree 6), right occipital pole (in-degree 5), right cerebellum 7b parcel (in-degree 15), and right cerebellum 8 parcel (in-degree 7, out-degree 1). ConclusionsThe observations in this study provide information about the casual interactions among brain parcels in resting state, helping reveal how different subregions of large-scale distributed neural networks are coupled together in performing cognitive functions.

The spectrum of acute vestibular neuropathy through modern vestibular testing: A descriptive analysis

ObjectiveAcute vestibular neuropathy (AVN), often referred to as vestibular neuritis, is a cranial neuropathy responsible for a significant proportion of cases of acute vertigo. This study describes the spectrum of lesion patterns in AVN as identified by video head impulse testing (vHIT) which assesses the high frequency vestibulo-ocular reflex function of the semicircular canals, and cervical and ocular vestibular evoked myogenic potentials (VEMPs) which assess otolith function. MethodsWe used vHIT and VEMPs to assess 35 patients with vestibular neuropathy in the acute stage. ResultsUnilateral superior division vestibular nerve involvement was the most common variant (57.1%), followed by unilateral superior and inferior division (28.5%), bilateral superior division (8.5%) and unilateral inferior division (5.7%). We observed a partial inverse correlation between the proportion of afferent fibers from an organelle, and the likelihood that the test of that organelle’s function will be abnormal. ConclusionvHIT and VEMPs provide more detailed characterization of lesion pattern in AVN than caloric testing. SignificanceComparison of lesion patterns from neuro-physiological testing with what is known about the proportional distribution of afferent fibers from the vestibular end-organelles suggests a new, neuro-anatomically based insight regarding susceptibility of these pathways to AVN.

437 - COGNITIVE, PATHOLOGICAL, GENETIC AND NEURO-RADIOLOGICAL CORRELATES OF CEREBRAL AMYLOID ANGIOPATHY

Background:Cerebral Amyloid Angiopathy related inflammatory process (CAA-ri), a rare condition caused by an inflammatory reaction occurring within essential cerebral blood vessels against beta-amyloid deposits, leads to subclinical cognitive decline. Often misdiagnosed as dementia, this process can be treated through aggressive immunosuppression, thereby reversing much of the cognitive impairment.Case Report:We report a 69 year old female who came to the clinic for a second opinion and had received a previous diagnosis of Alzheimer’s Dementia (AD) from an outside hospital two years prior. She presented with her husband who provided some key aspects of the history. The husband reported two years of worsening of memory, while the patient denied her symptoms. Per husband and patient, she was able to perform activities of daily living (ADLs), including bathing, dressing and toileting, but had difficulties with many instrumental ADLs (IADLs). The clinical course was somewhat fluctuating with progressive cognitive symptoms and significant word-finding difficulties. Patient had been started on Donepezil 5 mg daily by her primary provider.Results:On examination, the patient did exhibit significant word-finding difficulties and scored 12/30 on the Montreal Cognitive Assessment (MoCA), indicating moderate cognitive impairment. The Patient was as well confused and disoriented to time and place. Neurological examination was otherwise unremarkable. Magnetic Resonance Imaging (MRI) studies were ordered and showed patchy and diffuse T2/FLAIR hyper intensities and particularly concentrated in the posterior cerebral artery and inferior division of the middle cerebral artery. These findings were consistent with cerebral amyloid angiopathy related inflammation (CAA-ri). Besides susceptibility weighted image (SWI) was showing multiple widely distributed microhemorrhages typical for CAA.To address the acute inflammatory reaction the patient was hospitalized and received high dose, 3 day course of intravenous steroids, followed by an oral steroid taper. The treatment had to be monitored due to an unrelated hypertensive emergency and WPW syndrome (both newly diagnosed and treated emergently) thus the Patient was hospitalized for a 3 days and discharged on oral steroids tapper in improved condition.Additionally, imaging showed that the patient’s hippocampal volumes were within normal range so this particular imaging biomarker didn’t support the diagnosis of AD. CSF biomarkers analysis didn’t support the diagnosis of AD either since had p-Tau levels were found to be within normal limits. Patient was found to be homozygous for the APOE e4 gene. Follow-up evaluation (including a repeat MRI study) was performed 2 months later showed clinical recovery and near complete resolution of diffuse hyperintensities, suggesting inflammation had resolved. Both the patient and the husband reported significant improvement in orientation and other aspects of cognition including working memory. The Patient scored 26/30 on MoCA.Discussion:Cerebral amyloid angiopathy (CAA) has been commonly associated with brain hemorrhages in the elderly, but the inflammatory subtype CAA-I occur much less frequently and may be often misdiagnosed as a cancerous process (Ronsin et al. 2016). In a recent systematic review by Caldas A et al. 2015, of the 155 patients with documented CAA-I, almost half displayed some form of cognitive impairment and 86% received corticosteroids. Nearly half of the cases improved following treatment.Conclusion:We present a case of a patient previously diagnosed with AD, upon further investigation, likely CAA-I, treated aggressively with intravenous steroids to good effect. Although rare, CAA-I is a reversible disorder that may be masked by a dementia or/and delirious process and should be considered in patients showing relatively rapid and fluctuating cognitive decline.

Cervical and ocular vestibular evoked myogenic potentials in determining nerve division involvement in patients with a tumor located in the internal auditory canal

ObjectivesThe study aimed at the analysis of the parameters of acoustic cervical and ocular vestibular evoked myogenic potentials (AC-cVEMP and AC-oVEMP) response in patients with a confirmed tumor located in the internal auditory canal. It also aimed to assess to what degree a combination of these tests may be of benefit in the preoperative indication of the affected nerve division via preoperative determination whether the tumor originated from the superior or inferior division of the vestibular nerve, both divisions, or if it originated from a different nerve in the internal auditory canal. MethodsThe study group included 50 patients. Preoperative MRI scans were used to measure tumor diameter. AC-cVEMP and AC-oVEMP testing were performed before tumor resection. The surgeon was asked for a detailed description of the tumor origin. ResultsThe corrected amplitude of cVEMP was significantly lower on the tumor side than on the non-affected side and in the control group. The corrected Asymmetry Ratio (AR) of cVEMPs in patients with the tumor was significantly elevated above the reference values with the mean being 58.29% and the mean AR of oVEMPs in patients the tumor was 71.78% which made both results significantly higher than in the control group. Neither cVEMP nor oVEMP latency was significantly correlated with tumor size. Data obtained from cVEMP and oVEMP tests was an effective indicator of tumor origin in 74% of patients showing which division (or both divisions) of the VIIIth nerve was affected in comparison with information obtained from the surgeon. ConclusionsThe combined use of AC-cVEMP and AC-oVEMP tests may be useful in surgical planning in patients the tumor located in the internal auditory canal, providing a highly probable determination of the division of the affected nerve. Such information is valuable for the surgeon as it offers additional knowledge about the tumor before the procedure. cVEMP and oVEMP results may not be used as the basis for the calculation of tumor size in patients.

Multiple Acute Ischemic Strokes in a COVID-19 Patient: a Case Report.

We describe a case of a 47-year-old Italian, immunocompromised, and obese woman infected by COVID-19 presenting with fever (39.6 °C) and respiratory symptoms. Neurological examination was normal. Chest CT findings consist of bilateral interstitial pneumonia (visual score extension: 30%). The patient was treated with antiviral drugs and anti-inflammatory drugs with supportive care. Seven days after admission to Covid-19 Unit, the patient rapidly developed worsening respiratory failure and acute respiratory distress syndrome (ARDS). She suddenly developed partial left hemispheric syndrome. A new HRCT scan of her thorax revealed diffuse ground-glass opacities in both lungs (visual score extension: 90%). Brain CT performed 2 h after sudden-onset left-sided weakness showed subtle low attenuation within the right insular ribbon and frontal lobe (ASPECT Score 8). Multiphasic CT angiography (MCTA) demonstrated occlusion of both the dominant inferior division of the right middle cerebral artery and the A2 segment of the right anterior cerebral artery. After 24 h, her pupils became dilated and unreactive, and brain CT demonstrated large bilateral infarctions of both the cerebellar and cerebral hemispheres. She had a rapid progression of interstitial pneumonia from COVID-19, developed multiple strokes, and died 1 day later. SARS-CoV-2 infection seems to predispose pluripathological subjects to cerebrovascular complications.