DynaCT angiography for the diagnosis of bilateral bow hunter's syndrome

Ischemic Stroke Secondary to Dynamic Vertebral Artery Stenosis: Case Report and Review of the Literature

Ischemic stroke secondary to dynamic vertebral artery stenosis or occlusion, also known as “bow hunter's syndrome,” is a rare stroke mechanism. We report a case of a 24-year-old man with multiple hereditary exostosis (MHE) diagnosed at childhood. His first presentation to a neurologist was due to neck pain and clinical syndrome suggestive of ischemia in the vertebrobasilar territory. A therapeutic occlusion was done successfully without complication. The patient was discharged two days later on aspirin alone. In follow up one year later he continued to be symptom free. Moreover, this stroke mechanism has been reported extensively in the literature in isolation or secondary to many underlying diseases. In total, there are 168 cases reported in the published English literature, in either case reports or small series. In this review, we found that by far, vertebral artery occlusion at the atlanto-axial (C1-2) level dominated most reported cases. The most frequent presentation that led to further investigation was syncope or pre-syncope provoked by head rotation to one side. To our knowledge, there is no previous report of any stroke syndrome related to MHE before our case. In this paper, we report the first case secondary to MHE and review the literature up to date since the first reported case in 1952.

Cone-beam computed tomography for trauma

Radiographic imaging is critical in helping guide treatment of critically injured patients. Cone-beam computed tomography is an axial imaging technique available from fixed imaging systems found in hybrid operating rooms. It can be used to provide focused studies of specific anatomical regions, where patients cannot undergo conventional multidetector computed tomography. This includes non-contrast-enhanced evaluation of the intracranial contents and vascular imaging throughout the body. There are a number of advantages and disadvantages to cone-beam computed tomography, but these are not widely discussed within the trauma literature. This narrative review article presents the initial practical experience of this novel imaging modality. LEVEL OF EVIDENCE: Review article, level III.

Clinical application of percutaneous kyphoplasty under the guidance of DynaCT in the treatment of compression fractures of thoracolumbar

OBJECTIVES

This study aims to investigate the clinical application values of percutaneous kyphoplasty (PKP) under the guidance of DynaCT in the treatment of compression fractures of thoracolumbar.

METHODS

57 patients with compression fractures of thoracolumbar who were treated with PKP in The Second People's Hospital of Weifang from December 2014 to August 2016 were selected. Patients were randomly divided into DynaCT+DSA treatment group (27 cases) and DSA treatment group (30 cases) for PKP surgery. There were 19 cases of simple thoracic compression fractures, 28 cases of simple lumbar compression fractures, and 10 cases of thoracic vertebral compression fractures. Bone cement filling and leakage conditions were recorded after surgery. Efficacy of PKP was evaluated at 3 days after operation using visual analogue scale (VAS) and the maximal depth of the affected vertebrae. 71 lesioned vertebrae were treated and all punctures were successful.

RESULTS

VAS score and height of the largest depression in vertebrae were significantly improved after surgery (p<0.05), while no significant differences were found between 2 groups. The leakage rate of bone cement in the two groups was 24.3% and 18.4%, respectively.

CONCLUSION

DynaCT can be used to guide the development of vertebral puncture program before PKP, guide the accurate puncture during operation, and can be used to evaluate the leakage of bone cement timely and reliably.

Bow Hunter's Syndrome by Nondominant Vertebral Artery Compression: A Case Report, Literature Review, and Significance of Downbeat Nystagmus as the Diagnostic Clue

BACKGROUND

Bow hunter's syndrome (BHS) is rare and typically induced by mechanical compression of the dominant vertebral artery (VA) during head rotation. We report a case of BHS induced by nondominant VA compression in which contralateral VA patency was preserved. Definite diagnosis of BHS is not often feasible because of transient symptoms and nonspecific clinical features, such as vertigo or dizziness, especially in nondominant VA compression. We discuss the diagnostic clues of BHS and clinical features of BHS caused by nondominant VA compression through a literature review.

CASE DESCRIPTION

A 65-year-old man suffered repeated bouts of dizziness whenever his head was rotated to the left. This dizziness was consistently accompanied by downbeat nystagmus (DBN). Radiography revealed left VA compression by a lateral osteophyte at the C3-C4 level only during left head rotation. In contrast, patency of the right VA, which was almost equivalent in size to the left VA, was preserved during head rotation. The distinctive clinical finding of head rotation-induced DBN, which is usually associated with lesions involving the caudal midline cerebellum, was observed. Symptoms disappeared immediately after left VA decompression with osteophytectomy and C3-C4 fusion.

CONCLUSIONS

Despite excellent flow through the contralateral VA, occlusion of the nondominant VA occasionally induces BHS. According to a review of the literature, BHS cases do not always depend on the VA on one side for blood supply. Head rotation-induced DBN can be useful for diagnosis of BHS, even in cases of nondominant VA compression.