Flow In Left Vertebral Artery Research Articles

Bow Hunter's Syndrome: Complete Microsurgical Decompression of Vertebral Artery by Far Lateral Retrocondylar Approach: 3-Dimensional Operative Video.

This 50-yr-old man had a 15-yr history of presyncopal episodes that were precipitated by turning his head to the right, and had worsened recently. Cerebral angiogram demonstrated complete cessation of anterograde flow in left vertebral artery (VA) at the level of the C1 sulcus arteriosus while turning head to right, indicating dynamic compression at the C1 level. Patient underwent left extreme lateral retrocondylar approach, partial C1 laminectomy and opening of the C1 foramen with complete microsurgical decompression of the VA. After skin incision, meticulous muscle dissection was performed and superior and inferior oblique muscles were disconnected from the tubercle of C1. The VA was exposed, and three areas of constriction were visible, first at the atlanto-occipital membrane laterally; second, located more medially as the artery curved around the occipital condyle to enter the posterior fossa; and third, located anterior to C2 nerve root. The artery was dissected from all the surrounding tissues, preserving the C2 nerve root, and the Cl foramen was opened completely. The Cl lamina was also partially resected and grooved to allow free placement of the VA. The VA was also decompressed near the C2 foramen. Postoperative computed tomography angiogram of the head and neck showed complete decompression of VA. The patient had no episodes of presyncope or dizziness while turning head to right and his mRs was 0 at 8 mo follow up. This 3D video shows the technical nuances of decompression of V3 segment of VA in bow hunters's syndrome. Informed consent was obtained from the patient prior to the surgery that included videotaping of the procedure and its distribution for educational purposes. All relevant patient identifiers have also been removed from the video and accompanying radiology slides.

鈍的頸椎損傷に合併する椎骨動脈閉塞症例の検討(Vertebral artery occlusion associated with blunt traumatic cervical spine injury)

要旨【目的】鈍的頸椎損傷に合併する椎骨動脈損傷（以下VAI）は，時に重篤な脳梗塞を生じるが，確立された治療指針はない。我々は不安定型頸椎損傷に合併する椎骨動脈閉塞の症例を血管内治療の適応とし，整復固定術前に塞栓術を行ってきた。当院のVAI症例を検討し，椎骨動脈閉塞症例に対する塞栓術や長期予後について報告する。【対象】2015年1月～2018年4月に入院加療を行った全鈍的頸椎外傷症例を対象とした。頭頸部造影CT検査にてVAIの合併を認めた症例について，患者背景，頸椎損傷の形態，Denver grade，治療内容，脳梗塞合併の有無を後方視的に検討した。【結果】対象の鈍的頸椎外傷患者は89例で，15例（16.7%）にVAIを合併した。VAI患者の平均年齢は62.6歳で，半数が転倒転落を受傷機転とした。VAIの原因となった頸椎損傷は①亜脱臼，②環椎破裂骨折，③横突起骨折の3つであった。Denver grade IVの症例が最も多く12例であり，うち整復固定術を必要とした9例に血管内治療を行い，入院中および退院後のフォローにおいて明らかな脳梗塞を生じた症例は認めなかった。【結語】不安定性頸椎損傷に合併する椎骨動脈閉塞症例に対する整復固定術前の予防的塞栓術は，脳梗塞発症の予防に有効な治療手段となる可能性がある。

Vertebral Artery Stenting With Flow Reversal

A 47-year-old man was admitted with recurrent symptoms of dysarthria, diplopia, vertigo, and drop attacks. Workup revealed >90% stenosis of the left vertebral artery at its origin with poststenotic dilatation (Fig 1). The vertebral artery was 4 mm in diameter. The plaque appeared to have significant embolic potential. The right common femoral artery was accessed with short 9F sheath, and patient was anticoagulated with intravenous heparin (100 U/kg body weight). The left subclavian artery was cannulated using headhunter catheter. The catheter was advanced over the wire to mid brachial artery. Wire exchanged to stiff wire. MoMa flow reversal guide catheter (Medtronic, Minneapolis, Minn) was advanced over the stiff wire until the trailing balloon was engaged in the left subclavian artery. The leading balloon was positioned in left subclavian artery and kept deflated. The trailing balloon in left subclavian artery was inflated after making sure that activated clotting time was >250 seconds. An angiogram was performed to ensure that there was no antegrade flow in left vertebral artery (Fig 2). Spartacore 0.014 wire (Abbott Labs, Abbot Park, Ill) was introduced through the working port of MoMa guide catheter and was used to cross the area of near occlusive stenosis in proximal part of left vertebral artery. The lesion was successfully stented open with 4- × 18-mm Herculink Elite (Abbott Labs) balloon-expandable stent (Fig 3). The stent was projected in the left subclavian artery for about 1 mm. The stented segment of vertebral artery was aspirated multiple times with Export catheter (Medtronic). A significant amount of atherosclerotic debris was aspirated (Fig 4). Antegrade blood flow was restored. The MoMa device balloon in subclavian artery was deflated. Completion arteriogram revealed brisk flow in left vertebral artery, without any residual stenosis. The patient remained stable, without any adverse neurologic events. Sheath and guiding catheter was removed and hemostasis secured. The 60-day follow-up revealed multiphasic flow in the left vertebral artery and patient remained symptom free. View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT) Vertebral artery stenting with flow reversal as embolic protection is very safe and effective strategy for endovascular vertebral artery interventions in select group of patients.

Hybrid Endovascular Surgical Repair in Takayasu's Arteritis: Duplex Ultrasound Follow-up

Introduction Takayasu's arteritis (TA), a rare condition occurring primarily in young women, is a granulomatous vasculitis usually affecting the aorta and its branches. Our case report describes the duplex ultrasound findings in a 16-year-old Hispanic woman after a hybrid endovascular procedure. Patient Description TA in this patient was diagnosed in 2005 after a pulsatile neck mass developed on the right side of her neck. To date, she has required four vascular interventions in less than 3 years. The first procedure was an aortic root, ascending aorta and aortic arch replacement with Dacron graft replacement of the left common carotid and innominate arteries. She then developed a pseudoaneurysm in the distal left common carotid artery replacement graft, which was excluded with a stent-graft. The third procedure was a balloon angioplasty of an anastomotic stenosis of the aorto-innominate artery graft. This, however, recurred and there was also a small anastomotic pseudoaneurysm at this site. Revascularization was complicated by the fact that the left subclavian artery was occluded, with reversed flow in the left vertebral artery. Consequently, preservation of antegrade flow in the right vertebral artery was a priority. Transposition of the right common carotid artery to the subclavian artery with placement of a balloon expandable stent graft from the aortoinnominate artery graft into the subclavian artery (proximal to the vertebral artery) was performed. Methods All available imaging exams and operative reports were reviewed. Bilateral carotid duplex evaluation in addition to duplex examination of all bypasses and the distal native arteries were performed using high resolution ultrasound equipment and probes of varying frequency. Results Normal caliber wall thickness was identified in bilateral common carotid arteries. No evidence of intimal hyperplasia could be detected in stented areas. All open surgical or endovascular repair sites were well visualized, with the exception of only the proximal most innominate artery bypass graft and the aortic arch. Primarily retrograde left vertebral artery flow feeds the left subclavian artery. There was no evidence of restenosis or pseudoaneurysm formation. Discussion Long-term follow-up of the patient with TA after open surgical or endovascular procedures is extremely important because of the chronic nature of the disease process. Duplex ultrasound is a safe, effective adjunct to the standard radiologic arsenal usually used to follow these high-risk patients.

Imaging diagnosis of subclavian steal syndrome secondary to takayasu arteritis affecting a left-side subclavian artery

Takayasu arteritis (TA) is a rare form of large-vessel, chronic, occlusive vasculitis. It involves mainly aorta and its main branches, causing stenosis and/or obstruction. Its frequency has been estimated at 2.9 cases per 1 million people. Epidemiologically, it is found principally in young female patients and is more prevalent in Asia and Latin America. When there is severe stenosis or occlusion in subclavian artery, the phenomenon of subclavian steal syndrome (SSS) occurs, which usually causes symptoms of the vertebrobasilar territory because blood supply to the arm is sustained by reversal of flow in ipsilateral vertebral artery. We describe a case of SSS thought to be due to TA in a Mexican woman. Doppler ultrasound of neck vessels showed retrograde flow in left vertebral artery during systole. Digital subtraction angiography confirmed 30% stenosis of left subclavian artery with filling of left vertebral artery in retrograde direction. In presenting this case, we carried out a brief review of TA, main features in imaging diagnosis of SSS, and the infrequently reported association of TA with SSS.

動静脈シャントにより鎖骨下盗血現象をきたした透析患者の一例

We report a case of reversed vertebral artery blood flow in a patient with hemodialysis arteriovenous fistula. The patient was a 65-year-old woman who had been diagnosed as having chronic glomerulonephritis and hypertension at the age of 42. The arteriovenous fistula for hemodialysis had been made in her left arm when she was 62 years old. We carried out initial Doppler sonography vascular evaluation of the neck in June 1999. This showed that blood flow in the vertebral arteries was antegrade bilaterally with a maximum flow velocity of 73.0 cm/s in the right and 42.6 cm/s in the left. We re-evaluated the patient in January 2001 and found that the blood flow was retrograde in the left vertebral artery, with a maximum flow velocity of 60.7 cm/s. During compression of the left brachial artery, the left vertebral artery flow became antegrade. The patient had no signs or symptoms suggesting vertebrobasilar insufficiency.We consider that the reversed left vertebral flow in this case was a subclavian steal phenomenon caused by the arteriovenous fistula in the patient's arm. We suggest that Doppler evaluation of vertebral artery blood flow is useful in patients with arteriovenous fistulas for hemodialysis.