Bow-hunter’s syndrome caused by dynamic vertebral artery stenosis at the cranio-cervical junction—a management algorithm based on a systematic review and a clinical series

Abstract

Bow hunter's syndrome (BHS) is defined as symptomatic, vertebro-basilar insufficiency caused by mechanical occlusion of the vertebral artery (VA) at the atlanto-axial level during head rotation. In the literature, about 40 cases have been reported. However, due to the rarity of this pathology, there are no guidelines for diagnosis and treatment. Conservative, surgical, and endovascular concepts have been proposed. In order to work out an algorithm, we performed a systematic review of the literature and a retrospective analysis of patients, which have been treated in our institutions over the last decade. The clinical series was comprised of five patients. The symptoms ranged from transient vertigo to posterior circulation stroke. Diagnosis was established by dynamic angiography. In all patients, the VA was decompressed; one patient required additional fusion. The clinical and radiological results were good, and the treatment-related morbidity was low. The literature review demonstrated that Bow hunter's syndrome is a rare pathology but associated with a pathognomonic and serious clinical presentation. The gold standard of diagnosis is dynamic angiography, and patients were well managed with tailored vertebral artery decompression. By this management, clinical and radiological results were excellent and the treatment-related morbidity was low.

Rotational Vertebral Artery Occlusion

“…Only a previous review of published cases described that ≈50% of patients treated conservatively developed stroke with permanent neurological deficits. 2,[25][26][27] Our study showed a favorable long-term outcome of conservative treatments in RVAO. None of our patients with conservative treatments developed posterior circulation stroke, and 4 of them showed resolution of the symptoms during the follow-up, possibly because of spontaneous resolution of the extrinsic compression or central adaptation.…”

“…40 On the basis of their safety, effectiveness, and good longterm outcome, surgical treatments, including cervical decompression or cervical spine fusion, have been recommended as the first line treatment option of RVAO. 2,23,[25][26][27] Although cervical spine fusion provides complete relief of the symptoms and no reocclusion of the VA, most patients experience a significantly restricted range of head motion postoperatively, which restrains daily activities. 23 However, cervical decompression does not limit physiological neck movements, but it has a problem of high reocclusion rate because of postoperative adhesion between the VA and the adjacent soft tissues.…”

“…2,[23][24][25][26][27] Because a previous review of published cases revealed that ≈50% of patients with conservative treatments developed stroke with permanent neurological deficits, 2 surgical decompression has generally been recommended in patients with RVAO. However, long-term outcome of conservative treatment remains to be elucidated in RVAO.…”

Rotational vertebral artery occlusion secondary to adjacent-level degeneration following anterior cervical discectomy and fusion

“…Therefore, surgical treatment was indicated. A recently published treatment algorithm for bow hunter's stroke by Cornelius et al 7 agrees with this strategy; due to a lack of evidence and risk of stroke, the authors discouraged conservative therapy with cervical collars.…”

Revisión sobre el vértigo cervical

“…TRATAMIENTO DEL MAREO DE CAUSA CERVICAL Si se trata de un vértigo por oclusión de la arteria vertebral, en función de las característi-cas, el tratamiento es variable, desde la descompresión quirúrgica al uso de anticoagulantes [41]. En estos pacientes la terapia física no estaría indicada e incluso pudiera ser contraproducente [27].…”