Cervical anterior spinal artery infarction associated with anomalous vertebral artery: a case report.

We report a unique case of cervical anterior spinal artery (ASA) infarction in a 49-year-old male with hypercholesterolemia and sleep apnea. The patient experienced sudden cervical pain, quadriparesis, areflexia, and urinary incontinence after swallowing a large food bolus. Imaging revealed an infarction at the C3-C5 levels and an anomalous right vertebral artery (VA) originating from the thoracic aorta, tightly enclosed between the aorta and a vertebral column with an anterior osteophyte. This aberrant VA was the primary vascular supply to the ASA, with no contribution from the left VA or supreme intercostal arteries. We propose that transient injury to the right VA, induced by compression between the aortic arch, the food bolus, and the osteophyte, led to temporary hypoperfusion of the ASA, causing a watershed ischemic injury in the mid cervical cord's anterior gray matter. The article also provides an in-depth discussion of the developmental and clinical characteristics associated with this rare vascular anomaly.

Decreasing Spatial Variability of Individual Watershed Areas by Revascularization Therapy in Patients With High-Grade Carotid Artery Stenosis.

BACKGROUND: Carotid artery stenosis can impair cerebral hemodynamics especially within watershed areas (WSAs) between vascular territories. WSAs can shift because of collateral flow, which may be an indicator for increased hemodynamic implications and hence higher risk for ischemic stroke. However, whether revascularization treatment can reverse the spatial displacement of individual WSAs (iWSAs) and impaired hemodynamics remains unknown. HYPOTHESIS: That iWSAs spatially normalize because of hemodynamic improvement resulting from revascularization treatment. STUDY TYPE: Prospective. POPULATION: Sixteen patients with unilateral, high-grade carotid artery stenosis confirmed by duplex ultrasonography and 17 healthy controls. FIELD STRENGTH/SEQUENCES: A 3 T-magnetization-prepared rapid acquisition gradient echo (MPRAGE), gradient-echo echo planar dynamic susceptibility contrast (DSC), and fluid-attenuated inversion recovery (FLAIR) sequences. Additionally, contrast-enhanced 3D gradient echo magnetic resonance angiography (MRA) and diffusion-tensor imaging (DTI) spin-echo echo planar imaging were performed. ASSESSMENT: iWSAs were delineated by a recently proposed procedure based on time-to-peak maps from DSC perfusion MRI, which were also used to evaluate perfusion delay. We spatially compared iWSAs and perfusion delay before and after treatment (endarterectomy or stenting). Additionally, the Circle of Willis collateralization status was evaluated, and basic cognitive testing was conducted. STATISTICAL TESTS: Statistical tests included two-sample t-tests and Chi-squared tests. A P value < 0.05 was considered to be statistically significant. RESULTS: After revascularization, patients showed a significant spatial shift of iWSAs and significantly reduced perfusion delay ipsilateral to the stenosis. Spatial shift of iWSA (P = 0.007) and cognitive improvement (P = 0.013) were more pronounced in patients with poor pre-existing collateralization. Controls demonstrated stable spatial extent of iWSAs (P = 0.437) and symmetric perfusion delays between hemispheres over time (P = 0.773). DATA CONCLUSION: These results demonstrate the normalization of iWSA and impaired hemodynamics after revascularization in patients with high-grade carotid artery stenosis. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 2.

Multiple cerebral infarctions associated with lung cancer-induced hypereosinophilia: a case report.

BACKGROUND: Hypereosinophilia (HE) is caused by various conditions, including solid and hematologic tumors. Nonetheless, there exist no reports on cerebral infarctions caused by HE associated with lung cancer metastasis to the bone marrow. CASE PRESENTATION: We report a case of a 67-year-old man with multiple cerebral infarctions associated with HE. His white blood cell and eosinophil counts were 38,900/µL and 13,600/µL, respectively, at 4 weeks before admission. During treatment for HE, he presented with dysarthria and walking difficulties. Magnetic resonance imaging of the brain showed multiple small infarcts in regions such as the bilateral cortex, watershed area, and cerebellum. Chest computed tomography showed small nodes in the lung and enlargement of the left hilar lymph nodes. Bronchoscopic biopsy did not reveal a tumor; however, bone marrow biopsy showed infiltration of tumor cells. We considered a diagnosis of lung cancer metastasizing to the bone marrow, which induced HE and later caused cerebral infarctions. CONCLUSIONS: This case report demonstrates that metastatic cancer in the bone marrow can induce HE, which can consequently cause multiple cerebral infarctions. Clinicians should consider HE as a cause of multiple cerebral infarctions in patients with cancer.

Increased variability of watershed areas in patients with high-grade carotid stenosis.

PURPOSE: Watershed areas (WSAs) of the brain are most susceptible to acute hypoperfusion due to their peripheral location between vascular territories. Additionally, chronic WSA-related vascular processes underlie cognitive decline especially in patients with cerebral hemodynamic compromise. Despite of high relevance for both clinical diagnostics and research, individual in vivo WSA definition is fairly limited to date. Thus, this study proposes a standardized segmentation approach to delineate individual WSAs by use of time-to-peak (TTP) maps and investigates spatial variability of individual WSAs. METHODS: We defined individual watershed masks based on relative TTP increases in 30 healthy elderly persons and 28 patients with unilateral, high-grade carotid stenosis, being at risk for watershed-related hemodynamic impairment. Determined WSA location was confirmed by an arterial transit time atlas and individual super-selective arterial spin labeling. We compared spatial variability of WSA probability maps between groups and assessed TTP differences between hemispheres in individual and group-average watershed locations. RESULTS: Patients showed significantly higher spatial variability of WSAs than healthy controls. Perfusion on the side of the stenosis was delayed within individual watershed masks as compared to a watershed template derived from controls, being independent from the grade of the stenosis and collateralization status of the circle of Willis. CONCLUSION: Results demonstrate feasibility of individual WSA delineation by TTP maps in healthy elderly and carotid stenosis patients. Data indicate necessity of individual segmentation approaches especially in patients with hemodynamic compromise to detect critical regions of impaired hemodynamics.

Unique Angiographic Appearances of Moyamoya Disease Detected with 3-Dimensional Rotational Digital Subtraction Angiography Imaging Showing the Hemodynamic Status.

BACKGROUND: The aim of this study was to identify the unique morphological arterial features in patients with moyamoya disease on 3-dimensional rotational digital subtraction angiography. MATERIALS AND METHODS: One hundred seven hemispheres of 58 consecutive patients with moyamoya disease that were analyzed with fused 3-dimensional images of internal carotid angiograms and vertebral angiograms that were marked with different colors were reviewed. Angiographic findings in the posterior watershed area were classified, and the utility of the classification was analyzed by comparing it with clinical presentations and quantitative hemodynamic parameters obtained with positron emission tomography. RESULTS: Two unique angiographic appearances were identified. A vacant vessel appearance (no arterial inflow despite absence of cortical infarction) was observed mostly in transient ischemic attack hemispheres. In hemispheres with a vacant vessel appearance, cerebral blood flow was decreased, cerebral blood volume was increased, and mean transit time was prolonged significantly (P = .00017, P = .0061, and P = .00026, respectively). A cocktail vessel appearance (mixture of carotid and vertebral arterial flow) was most commonly observed in asymptomatic cases, as well as in ischemic hemispheres. Cerebral blood volume increased and mean transit time was prolonged significantly (P = .036 and P = .014, respectively) in hemispheres with a cocktail vessel appearance. The trend of progression in hemodynamic severity in the order of normal appearance, cocktail vessel appearance, and vacant vessel appearance in the watershed area was statistically significant. CONCLUSION: Fused 3-dimensional digital subtraction angiography demonstrated unique angiographic features in the watershed area, and this represented the degree of cerebral hemodynamic impairment in moyamoya disease.

Using fluorescence lymphangiography to define the ileocolic mesentery: proof of concept for the watershed area using real-time imaging.

Recent advances in mesenteric science have demonstrated that the mesentery is a continuous structure with a 'watershed' area at the mesenteric apex between the right colon and terminal ileum, where lymphatic flow can proceed either proximally or distally. With this new understanding of the anatomy, functional features are emerging, which can have an impact on surgical management. Fluorescence lymphangiography or lymphoscintigraphy with indocyanine green allows real-time visualization of lymphatic channels, which highlights sentinel lymph nodes and may facilitate identification of the ideal margins for mesenteric lymphadenectomy during bowel resection for colon cancer. By using this novel technology, it is possible to demonstrate a watershed area in the ileocolic region and may facilitate more precise mesenteric dissection. In the present study, we provide proof of concept for the ileocolic watershed area using fluorescence lymphangiography.

Hypometabolism of watershed areas of the brain in HTLV-1-associated myelopathy/tropical spastic paraparesis.

In previous studies of human T-lymphotropic virus type 1-associated myelopathy/tropical spastic paraparesis (HAM/TSP), areas of slow blood flow in the spinal cord were related to pathological changes. While the pathological changes in the brain are milder than those in the spinal cord, they are also more significant in sites with slow blood flow. In this study, we investigated brain glucose metabolism in slow blood flow areas using fluorine-18 fluorodeoxyglucose positron emission tomography ((18)F-FDG-PET). Clinical features and brain (18)F-FDG-PET parameters were analyzed in six patients with HAM/TSP. For comparison of PET data, eight healthy volunteers were enrolled as normal controls (NLs). Glucose metabolism in the watershed areas of the middle and posterior cerebral arteries, as compared with that in the occipital lobes as a control, was significantly lower in HAM/TSP patients than in NLs. This result confirmed the relationship between slow blood flow areas and hypometabolism in HAM/TSP, and is consistent with previous findings that pathological changes are accentuated in sites with slow blood flow.

Distribution of the Spinal Arteries in Adult Patients with Lumbar Spondylolysis.

INTRODUCTION : The pathology of lumbar spondylolysis is generally thought to begin with a stress fracture in adolescence. Stress fractures of the lower extremities occur in watershed areas with a poor vascular supply because of an inability to respond to stress and heal. This pathology has not been well researched in the lumbar spine. The aim of this study was to evaluate the distribution of the spinal arteries in patients with lumbar spondylolysis. METHODS : The extraosseous distribution of the arteries around the pars interarticularis was retrospectively investigated in 14 patients with colon cancer who underwent abdominal contrast-enhanced computed tomography (CE-CT) as part of a preoperative assessment at our hospital and were found to have spondylolysis at L5. RESULTS : All patients were found to have terminal-stage spondylolysis at L5 (1 unilateral, 13 bilateral). L5 segmental artery was absent in all cases. However, separate spinal arteries supplying the pars interarticularis at L5 were found above and below the transverse process at this level. CONCLUSION : All the patients had two separate arteries originating from the cranial and caudal sides that distributed to the superior and inferior articular processes, suggesting that the pars interarticularis is a posterior element containing a vascular watershed area. J. Med. Invest. 67 : 62-66, February, 2020.

Relationship between Cytotoxicity in the Hippocampus and an Abnormal High Intensity Area on the Diffusion-weighted Images of Three Patients with Transient Global Amnesia.

Objective An abnormal high intensity area (HIA) on diffusion-weighted imaging (DWI) indicates the presence of cytotoxic edema and has been reported to be observed in the hippocampus of patients with transient global amnesia (TGA). The appearance of an HIA on DWI is usually delayed after the onset of patients with amnesia in TGA; thus, the significance of the HIA was evaluated in patients with TGA. Methods Three adult TGA patients who had a unilateral HIA on DWI (right, n=2; left, n=1) were enrolled. These patients were hospitalized due to acute-onset amnesia. Amnesia subsided within 24 hours of hospitalization in all three patients. Results The HIA was confined to the upper lateral zone of the body in the unilateral hippocampus where the CA1 region exists. The lesions were confirmed after the improvement of amnesia in the three patients. The location of the lesions corresponded to the watershed area where the upper and lower hippocampal arteries were anastomosed. Conclusion Cytotoxicity caused by glutamate-mediated calcium influx in the neurons of the CA1 region was recently reported in the pathogenesis of TGA. Based on the pathogenesis, the cytotoxicity was considered to have been caused by calcium overload throughout the entire CA1 region, and amnesia occurred due to this cytotoxicity. The cytotoxicity was more marked in the lesions because of the lower blood flow in the watershed area and was prolonged after the function of the CA1 region (excluding the watershed area) improved, which led to cytotoxic edema in the lesions.