Objectives: Retrograde vertebral artery flow, the steal phenomenon, is most frequently caused by a flow-limiting stenosis of the proximal subclavian artery. The reversal of flow can be incomplete, resulting in bidirectional flow: retrograde in systole and antegrade in diastole. Less often, retrograde vertebral artery flow is the consequence of increased subclavian flow, as might occur with a well-functioning dialysis access fistula. Our objective was to evaluate bidirectional vertebral artery flow associated with dialysis access fistulas.
Methods: We retrospectively reviewed the direction of flow through the vertebral artery in systole and diastole of 335 patients with dialysis fistulas who had undergone extracranial cerebral vascular Doppler examinations.
Results: Fifteen patients had retrograde flow in their vertebral artery ipsilateral with the side of their fistula. There was completely reversed flow in 1 patient and bidirectional flow in the other 14. For each of these 14, the flow was antegrade in early systole and retrograde in diastole. Compression of the fistula restored the antegrade flow.
Conclusions: Under conditions of reduced subclavian artery flow, bidirectional vertebral artery flow will be retrograde in early systole and antegrade in diastole. Under conditions of increased subclavian artery flow, bidirectional flow through the vertebral artery will be antegrade in early systole and retrograde in diastole.
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http://dx.doi.org/10.1002/jum.14975 | DOI Listing |
Acta Med Okayama
December 2024
Department of Neurological Surgery, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences.
Tenosynovial giant cell tumor (TGCT) is a fibrous histiocytic tumor originating in the synovial membrane. While cervical TGCT may not be considered a common diagnosis preoperatively because it is relatively rare, it has a high recurrence rate and should be considered. Total resection is preferable, but it can be challenging due to the risk of damaging the vertebral artery.
View Article and Find Full Text PDFWorld Neurosurg
December 2024
Department of Neurosurgery, Zhongshan Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, Fu Jian, China. Electronic address:
Objective: This study aims to elucidate the anatomical principles governing the surrounding venous structures (VS) of the horizontal part of the third segment of the vertebral artery (V3h) and develop a safe and bloodless surgical technique for exposing V3h.
Methods: This study used ten formalin-infused cadaveric head specimens. The dissections were performed stepwise to simulate the far lateral approach process, exposing the V3h with a novel technique.
J Neurosurg Case Lessons
December 2024
Department of Neurosurgery, Warren Alpert Medical School of Brown University, Providence, Rhode Island.
Background: Rotational vertebral artery occlusion, or bow hunter's syndrome (BHS), is a rare but clinically important cause of vertebrobasilar insufficiency. Extrinsic compression of the artery is usually caused by osteophytes, fibrous bands, or lateral disc herniation and typically occurs in the setting of anatomical variations, leading to dynamic compromise of the posterior circulation. Neoplastic causes of BHS are rare.
View Article and Find Full Text PDFCureus
November 2024
Neuroradiology Department, Unidade Local de Saúde de São João, Porto, PRT.
Bone or cartilage anomalies affecting the arteries supplying the brain can be a structural cause of ischemic stroke. Due to their rarity, there is currently no standardized approach for evaluating and treating these so-called bony strokes. We present a case of a 79-year-old woman with a history of cranial settling due to rheumatoid arthritis (RA) and moderate disability, who presented with insidious dizziness and gait disturbances over three weeks.
View Article and Find Full Text PDFCureus
November 2024
Department of Pediatrics, Hyogo Prefectural Amagasaki General Medical Center, Amagasaki, JPN.
The clinical manifestation of intracranial mycotic aneurysms (ICMAs), which are rare but carry high risks of rupture and early mortality, remains poorly understood. We present a case of an ICMA that rapidly developed and ruptured after the diagnosis of meningitis caused by (), which rarely causes bacterial meningitis. A 54-year-old man presented with a headache that worsened on coughing, without altered consciousness or vomiting.
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