Decompression of the vertebral artery for bow-hunter's stroke. Case report

Compressive lesions of the head and neck: Common and uncommon must-know entities

There are many lesions that cause compression of nerves and vessels in the head and neck, and they can often be overlooked in the absence of adequate history or if not suspected by the radiologist. Many of these lesions require a high index of suspicion and optimal positioning for imaging. While a multimodality approach is critical in the evaluation of compressive lesions, an MRI utilizing high-resolution (heavily weighted) T2-weighted sequence is extremely useful as a starting point. In this review, we aim to discuss the radiological features of the common and uncommon compressive lesions of the head and neck which are broadly categorized into vascular, osseous, and miscellaneous etiologies.

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.

A Case of Posterior Circulation Embolism Due to a Subtype of Bow Hunter's Syndrome Diagnosed by Non-Invasive Examination

Bow hunter's syndrome is the mechanical compression of the vertebral artery due to cervical rotation, resulting in ischemic symptoms in the vertebrobasilar artery territory. However, some cases present without typical symptoms and exhibit compression of the non-dominant side of the vertebral artery. We encountered a case of posterior circulation embolism due to a subtype of bow hunter's syndrome in a 74-year-old man. Although the right vertebral artery was not visualized on time-of-flight magnetic resonance angiography in the neutral position, duplex ultrasonography and time-of-flight magnetic resonance angiography in the left cervical rotation position showed blood flow in the right vertebral artery. In this case, blood flow in the contralateral vertebral artery was normal, and typical bow hunter's syndrome symptoms did not occur. In a case of posterior circulation embolism with undetermined etiology, wherein the routine duplex ultrasonography and time-of-flight magnetic resonance angiography results were inconclusive, additional testing with head positioning led to the diagnosis of a subtype of bow hunter's syndrome.

Compression Syndromes of the Vertebral Artery at the Craniocervical Junction

Compression syndromes of the vertebral artery that occur at the craniocervical junction are extremely rare causes of haemodynamic insufficiency of the posterior cerebral circulation. The aetiology of the compression syndrome may be a malformation, trauma, tumour, infection or degenerative pathology. This may lead to dynamic vertebral artery occlusion where the vessel courses around the atlas and the axis-the so-called V3 segment. This in turn may result in insufficient collateral flow to the posterior fossa. The clinical picture is a vertebrobasilar insufficiency syndrome of variable expression ranging from vertigo to posterior fossa stroke. The typical clinical presentation is syncope occurring during rotation of the head, also known as 'bow hunter's syndrome'. The workup is based on dynamic angiography and computed tomography angiography. The treatment of choice is surgical vascular decompression, resulting in a good clinical outcome. However, in some instances, atlantoaxial fusion may be indicated. Alternatively, conservative and endovascular options have to be considered in inoperable patients.

C1-C2 Transverse Foramen Decompression by Anterolateral Approach as an Alternative Treatment in Bow Hunter's Syndrome

Bow hunter's syndrome (BHS) is characterized with repeating paroxysmal vertigo, nystagmus and ataxia caused by mechanical compression of the vertebral arteries. There is no definite diagnostic and treatment protocol. 26-year-old female patient admitted to the outpatient clinic with complaints of dizziness and seldom falls. Stenosis in the right vertebral artery at the level of C1 and C2 was discovered by the diagnostic modalities. In our patient, we first performed hemilaminectomy by posterior approach. But the symptoms of the patient did not recede, thus we performed decompression with the anterolateral approach by opening the foramens atlas and axis without disrupting the dynamics of the vertebrae and without the need for stabilization. The symptoms of the patient disappeared after this intervention. The patient had complete relief of symptoms at the first year follow up. Surgery must be planned to preserve the life quality of the patient and relieve complaints of the patients. To achieve these goals anterolateral approach must be tried before attempting posterior stabilization.

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.

Bow Hunter's Syndrome in a Patient with a Right Hypoplastic Vertebral Artery and a Dynamically Compressible Left Vertebral Artery

This is a case report of a 48-year-old man with multiple transient ischemic attacks and a known hypoplastic right vertebral artery (VA) who presented after a syncopal event while turning his head to the left. The objective of this study is to demonstrate the necessity of proper diagnosis and management of cerebrovascular pathology including imaging and surgical intervention in patients with known anatomical anomalies. This study was conducted at Massachusetts, United States of America. Our patient's history was significant for a hypoplastic right VA and a stenotic segment of the right VA at the C3–C4 junction. There was also degeneration of the C3–C4 facet on the left, with osteophyte formation compressing the VA, and a fusion of the C2–C3 segment. Imaging demonstrated obliteration of the left VA flow with head rotation to the left and subsequent reconstitution of flow in the neutral position. After consultation, the patient decided to proceed with surgical management with an anterior cervical discectomy and fusion at the level of C3–C4. Symptoms of vertebrobasilar insufficiency including syncopal episodes resolved after treatment. VA anomalies, although uncommon, are important to understand. Our patient presented with an anomalous right VA, as well as severe degenerative changes to the C2/C3 vertebrae that contributed to the development of Bow Hunter's syndrome. It is essential that proper monitoring and follow-up has to be carried out in patients with abnormal cerebral vasculature to minimize the occurrence of Bow Hunter's syndrome.

Juvenile Cerebral Infarction Caused by Bow Hunter's Syndrome during Sport: Two Case Reports

We report two cases of juvenile cerebral infarction caused by bow hunter's syndrome (BHS) during sport. Case 1 was a 17-year-old male who developed a partial visual field defect after playing basketball. BHS was diagnosed because cervical ultrasonography demonstrated occlusion of the vertebral artery when the neck was rotated. After C1-2 posterior fixation was performed, his symptoms resolved. Case 2 was an 18-year-old male with recurrent visual disturbance after playing handball. Cerebral infarction occurred repeatedly despite antiplatelet therapy. After 3 years, vertebral artery dissection was diagnosed and stenting was performed, but his symptoms did not resolve. BHS was diagnosed when he was examined at our department. C1-2 posterior fixation was performed and his symptoms resolved. In these two cases, BHS was caused by sporting activity. For accurate diagnosis and treatment of BHS, neuroimaging with cervical rotation is mandatory.

Advances in the Pathogenesis, Diagnosis and Treatment of Bow Hunter's Syndrome: A Comprehensive Review of the Literature

Bow hunter's syndrome (BHS), also known as rotational vertebral artery (VA) occlusion syndrome, is a rare yet treatable type of symptomatic vertebrobasilar insufficiency resulting from mechanical occlusion or stenosis of the VA during head and neck rotation or extension. The symptoms of BHS range from transient vertigo to posterior circulation stroke. The underlying pathology is dynamic stenosis or compression of the VA by abnormal bony structures with neck rotation or extension in many cases, such as osteophyte, disc herniation, cervical spondylosis, tendinous bands or tumors. Imaging approaches, such as Doppler sonography, computed tomography and angiography, as well as magnetic resonance imaging and angiography, are widely used in the diagnosis and evaluation of this syndrome. Digital subtraction angiography with head rotation remains the gold standard diagnostic method. Conservative management, surgery and endovascular procedures are the three major treatment methods for BHS, whereas some symptomatic patients may need operative treatment including surgery and endovascular procedures when conservative management is not adequate.

Bow hunter's syndrome revisited: 2 new cases and literature review of 124 cases

Rotational occlusion of the vertebral artery (VA), or bow hunter's syndrome, is a rare yet surgically treatable cause of vertebrobasilar insufficiency. The underlying pathology is dynamic stenosis of the VA by osteophytes, fibrous bands, or lateral disc herniation with neck rotation or extension. The authors present 2 previously unreported cases of bow hunter's syndrome and summarize 124 cases identified in a literature review. Both patients in the new cases were treated by VA decompression and fusion of the subaxial spine. Each had > 50% occlusion of the left VA at the point of entry into the transverse foramen with a contralateral VA that ended in the posterior inferior cerebellar artery. Analyzing data from 126 cases (the 2 new cases in addition to the previously published 124), the authors report that stenosis was noted within V1 in 4% of cases, in V2 in 58%, in V3 in 36%, and distal to C-1 in 2%. Patients presented in the 5th to 7th decade of life and were more often male than female. The stenotic area was decompressed in 85 (73%) of the 116 patients for whom the type of treatment was reported (V1, 4 [80%] of 5; V2, 52 [83%] of 63; V3/V4, 29 [60%] of 48). Less commonly, fusion or combined decompression and fusion was used (V2, 7 [11%] of 63; V3/V4, 14 [29%] of 48). Most patients reported complete resolution of symptoms. The authors conclude that patients with bow hunter's syndrome classically have an impaired collateral blood flow to the brainstem. This condition carries an excellent prognosis with decompression, fusion, or combined surgery, and individual patient characteristics should guide the choice of therapy.

Wake-up stroke in a young woman with rotational vertebral artery occlusion due to far-lateral cervical disc herniation

Wake-up stroke is most likely to be caused by small-vessel disease, and is related to snoring. The authors present a rare case of far-lateral cervical disc herniation with neck rotation, resulting in wake-up stroke in a young woman. The patient, a 31-year-old woman, was admitted to the hospital because of dysarthria and confusion when she awoke in the morning. Brain MRI showed acute infarction in the posterior fossa. Cerebral angiography showed thrombus in the distal top of the basilar artery and the bilateral posterior cerebral arteries. During angiography, the thrombus size decreased with heparinization. There was severe stenosis of the right vertebral artery (VA) at C5–6, and head rotation to the right resulted in complete occlusion of the right VA. Neck MRI showed far-lateral intervertebral disc herniation. Surgical decompression of the VA was performed via the anterior cervical approach. Histological examination showed a degenerative intervertebral disc. Postoperative angiography confirmed successful decompression of the VA.

Bow Hunter's Stroke Due to Stretching of the Vertebral Artery Fenestration: A Case Report

Bow Hunter’s syndrome is an unusual symptomatic vertebrobasilar insufficiency resulting from intermittent mechanical compression of the vertebral artery, and is rarely a trigger for cerebral infarction following thrombus formation on the damaged endothelial vessels (Bow Hunter’s stroke). The authors present an extremely rare case of a 45-year-old man showing Bow Hunter’s stroke due to congenital vertebral artery fenestration stretching and sliding between C1 and C2 after head rotation to the right. Congenital vertebral artery anomaly rarely causes cerebral infarction, but could cause embolic strokes by mechanical stretching without bony abnormalities.

Spontaneous atraumatic vertebral artery occlusion due to physiological cervical extension: case report

Vertebral artery (VA) occlusion is a serious and potentially life-threatening occurrence. Bow hunter's syndrome, a mechanical occlusion of the VA due to physiological head rotation, has been well described in the medical literature. However, mechanical VA compression due to routine flexion or extension of the neck has not been previously reported. The authors present the unique case of a woman without any history of trauma who had multiple posterior fossa strokes and was found to have dynamic occlusion of her right VA visualized via cerebral angiogram upon extension of her neck. This occlusion was attributed to instability at the occipitocervical junction in a patient with a previously unknown congenital fusion of both the occiput to C-1 and C-2 to C-3. An occiput to C-3 fusion was performed to stabilize her cervical spine and minimize the dynamic vascular compression. A postoperative angiogram showed no evidence of restricted flow with flexion or extension of the neck. This case emphasizes the importance of considering symptoms of vertebrobasilar insufficiency as a result of physiological head movement. The authors also review the literature on VA compression resulting from physiological head movement as well as strategies for clinical diagnosis and treatment.

Simultaneous bilateral stenosis of the vertebral arteries treated by unilateral decompression: a case report

A 56-year-old man presented with a 3-month history of progressive dizziness. His dizziness was aggravated when his head was rotated to the right side. Diagnostic angiography showed that a normal right-sided vertebral artery in the neutral position became an abnormal vertebral artery with two stenotic lesions at the C3-4 and C5-6 levels when the patient's head was turned to the right. A normal left-sided vertebral artery also showed a stenotic lesion at the C2 level when the patient's head was turned right. The axial dimensions of the bilateral vertebral arteries were similar. The patient was successfully treated with decompression of only one level (C5-6). We conclude that if a bilateral stenosis is found upon one directional head rotation and the bilateral vertebral arteries are similarly sized, a one-sided treatment may suffice.

[Scoliotic spine deformity in children and adolescents associated with the craniovertebral junction pathology]

This literature review is devoted to the clinical and pathogenic aspects of the relationship between Chiari type I malformation (CMT) and scoliosis. The view of the clinical presentation development in CMT associated with scoliosis is considered on the basis of both the CSF dynamics disturbances and vascular pathology of the craniovertebral junction. The role of the posterior atlanto-occipital membrane is evaluated. Case reports of the risk factors for scoliosis progression in patients with CMT are presented.

Bow hunter's syndrome causing vertebrobasilar insufficiency in a young man with neck muscle hypertrophy

Vertebrobasilar insufficiency is characterized by impaired blood flow within the posterior circulation, producing symptoms of vertigo, nausea, vomiting, visual disturbances, and syncope. Given these nonspecific symptoms, the diagnosis of vertebrobasilar ischemia may be difficult to distinguish from more benign conditions. A healthy 37-year-old man presented to our clinic with near syncope upon turning his head to the left. Dynamic angiography revealed occlusion of the left vertebral artery at C7 with 90° head rotation to the left, consistent with bow hunter's syndrome. No obvious bony abnormalities were identified on computed tomography or magnetic resonance imaging scans. Transient rotational vertebral artery syndrome, a rare cause of vertebrobasilar insufficiency, has most often been reported at the C1-2 level, and the majority of cases occur in patients >50 years of age because of degenerative osteophytes and contralateral atherosclerosis. We present the unusual case of a young man with symptoms of vertebrobasilar insufficiency and discuss the potential effects of weightlifting and neck muscle hypertrophy on vertebral artery flow dynamics.

Symptomatic vertebral artery stenosis secondary to cervical spondylolisthesis

STUDY DESIGN

Case report.

OBJECTIVE

To present a rare case of vertebrobasilar insufficiency (VBI) syndrome secondary to the C6 level isthmic spondylolisthesis.

SUMMARY OF BACKGROUND DATA

VBI associated with voluntary head movements is known as the bow hunter syndrome. It may manifest in temporary symptoms of dizziness, syncope, nausea, or motor and sensory deficits in certain head positions. The present syndrome is rare and difficult to diagnose. The authors describe a VBI case caused by vertebral artery compression due to the C6 level isthmic spondylolisthesis (to date, the authors have not found any other similar case described in the literature).

METHODS

The patient was a 27-year-old male with a 12-month history of vertigo and dizziness in relation to head movements. These problems interfered with his day-to-day activities.With other causes of neurological and cardiac origin dismissed, the patient was sent for an orthopedic evaluation.Radiological imaging showed spondylolisys, spondylolisthesis, and spina bifida between the facets of the C6 and C7. Dynamic radiographies evidenced C6 and C7 cervical instability.Angio-MRI indicated an anomalous trajectory of the right vertebral artery at the C6 level upon entering the foramen transversarium. However, there were no signs of stenosis. Dynamic angiography confirmed partial stenosis of the right vertebral artery upon rightward head rotation. The substantial suspicion of positional VBI after rejecting other diagnoses and the significant disability of the patient led to treating the patient with anterior cervical arthrodesis at the C6-C7 level.

RESULTS

The patient was symptom free for more than 15 months' monitoring and returned to all his daily work and life activities.

CONCLUSION

Isthmic spondylolisthesis must be considered as a cause within VBI. Surgery presents good results.

Rotational Vertebral Artery Compression : Bow Hunter's Syndrome

Bow hunter's syndrome (BHS) is rare cause of vertebrobasilar insufficiency that arises from mechanical compression of the vertebral artery by head rotation. There is no standardized diagnostic regimen or treatment of BHS. Recently, we experienced 2 cases resisted continues medication and treated by surgical approach. In both cases, there were no complications after surgery and there were improvements in clinical symptoms. Thus, we describe our cases with surgical decompression with a review of the relevant medical literature.

Bowhunter's syndrome diagnosed with provocative digital subtraction cerebral angiography

Bowhunter's syndrome, also known as rotational occlusion of the vertebral artery, involves posterior circulation ischemia resulting from dynamic compromise of the dominant vertebral artery. This case highlights the importance of provocative digital subtraction angiography in making the diagnosis. A 41-year-old man presented for outpatient neurological evaluation for "lightheadedness" of several years' duration provoked by leftward head rotation. The only abnormality identified on initial magnetic resonance angiography was atresia of the nondominant left vertebral artery. Conventional digital subtraction angiography (DSA) followed by provocative DSA revealed development of a dynamic stenosis of the right vertebral artery involving the extraforaminal segment just superior to the C1 vertebra. Noncontrast computed tomography of the cervical spine confirmed ossification of the posterior right atlanto-occipital membrane leading to a near complete bony arcuate foramen. Following neurosurgical decompression, the patient demonstrated complete resolution of all neurologic symptoms. Bowhunter's syndrome is a unique clinical entity that must be considered in the evaluation of patients with symptoms of posterior circulation ischemia. Provocative DSA remains the preferred modality for definitive diagnosis.

Rare case of bilateral vertebral artery stenosis caused by C4-5 spondylotic changes manifesting with bilateral bow hunter's syndrome

BACKGROUND

Rotational vertebral artery occlusion syndrome refers to vertebrobasilar insufficiency as a result of mechanical occlusion or stenosis of the vertebral artery by head rotation. In most cases, symptoms are produced on extension or rotation to one side. No case of bow hunter's syndrome with bilateral presentation at the C4 level has yet been reported.

CASE DESCRIPTION

A 54-year-old man presented with symptomatic bilateral bow hunter's syndrome induced by head rotation. The patient complained of intermittent dizziness, episodes of double vision, nonpulsatile tinnitus, and headaches indicative of vertebral artery insufficiency with exacerbation of symptoms on rotation of his head to either side. Computed tomography angiography showed bilateral vertebral artery stenosis, and dynamic cerebral angiography revealed bilateral rotational vertebral artery occlusion, with compression of the ipsilateral vertebral artery on head rotation to either side. Bilateral surgical decompression at C4-5 with anterior cervical diskectomy and fusion with a plate was performed.

CONCLUSIONS

Bony obstruction of the vertebral artery on head rotation tends to occur at levels C4 and below, affecting the ipsilateral side. In this rare case, symptomatic bilateral vertebral artery stenosis occurred as a result of bony compression and was symptomatic on head rotation both to the right and to the left. This stenosis was improved with anterior decompression bilaterally, and no further events occurred postoperatively.

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

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.

Vertebral artery stenting for the treatment of bow hunter's syndrome: report of 4 cases

Bow hunter's syndrome (BHS) is a rare condition resulting from vertebrobasilar insufficiency secondary to mechanical occlusion or stenosis of the vertebral artery (VA) due to head rotation. Traditionally, surgical intervention with C1-C2 fusion or VA decompression was the mainstay of therapy. Endovascular intervention was rarely performed to treat BHS. We reviewed the neurointerventional database from July 2005 to October 2010 to identify all cases of BHS treated with VA stenting. Here we report clinical, technical, and outcome data for 4 patients with BHS who were treated with VA stenting. In all 4 of these patients, stenting was performed in the V2 segment (C2-C6) of the VA without significant technical difficulties. All patients reported symptomatic relief, and only minor or no residual stenosis was detected by dynamic digital subtraction angiography. Our findings indicate that VA stenting for the treatment of BHS is feasible, safe, and clinically effective. Endovascular techniques might offer an alternative, minimally invasive therapy for the treatment of BHS.

Bow hunter's stroke due to instability at the uncovertebral C3/4 joint

Bow hunter's stroke is typically due to mechanical compression or stretching of the dominant vertebral artery (VA) during contralateral head rotation against the bony elements of the atlas and axis. We report a case of vertebrobasilar insufficiency due to bilateral vertebral artery occlusion at the left C3-4 and the right C1-2 junction on rightward head rotation. A 64-year-old man experienced ischemic symptoms during 90° head rotation to the right with complete resolution of symptoms after returning his head to the neutral position. Dynamic cervical angiography with rightward head rotation showed severe compression of the right VA at the transverse foramen of C3-4 and mechanical stenosis of the left VA at the C1-2 level. During head rotation, the flow of the right VA was decreased more than the left side. Cervical 3-D computed tomography (CT) on rightward head rotation demonstrated displacement of the uncovertebral C3-4 joint, with excessive rotation of the C3 vertebral body. Based on these findings, instability at C3-4 was suspected to be the main cause of the vertebrobasilar insufficiency. Anterior discectomy and fusion at the C3/4 level were performed. Postoperatively, the patient experienced complete resolution of symptoms, and dynamic cervical angiography showed disappearance of the compression of the right VA. To our knowledge, this is the first reported case of bow hunter's stroke diagnosed by dynamic cerebral angiography and cervical 3-D CT without angiography, and treated by anterior decompression and fusion without decompression of the VA.

Rotational vertebral artery occlusion-series of 9 cases

BACKGROUND

Rotational vertebral artery syndrome (RVAS) is a rare entity about which previously published studies are mostly limited to individual case reports.

OBJECTIVE

To report our decade-long experience with this syndrome in 9 patients with compression ranging from the occiput to C6.

METHODS

We utilized a posterior approach for lesions rostral to C4 and an anterior approach for lesions at or caudal to C4. Furthermore, we demonstrated the feasibility and efficacy of a minimally invasive posterior cervical approach. Patient profile, operative indications, surgical approach, operative findings, complications, and long-term follow-up were reviewed and discussed.

RESULTS

Average follow-up was 47 months. All procedures provided excellent outcomes by Glasgow Outcome Scale scores. The anterior approach had significantly less blood loss (187.5 mL vs 450 mL, P = .00016) and shorter hospitalization length (2 days vs 4.5 days; P = .0001) compared with the far-lateral approach. There was one complication of cervical instability in the far-lateral approach cohort. As an alternative to the far-lateral surgery, a minimally invasive approach resulted in shorter hospitalization (2 days) and less blood loss (10 mL) while avoiding the complication of cervical instability.

CONCLUSION

We demonstrated the safety, efficacy, and durability of 3 surgical approaches for RVAS. Proper examination, preoperative imaging, and surgical planning were necessary for a satisfactory outcome.

Rotational vertebral artery occlusion in a child with multiple strokes: a case-based update

INTRODUCTION

Rotational vertebral artery occlusion (RVAO), sometimes known as "Bow hunter syndrome," is an important and diagnostically challenging cause of posterior circulation stroke in children. It is caused by impingement of osseous and/or ligamentous structures on the vertebral artery.

DISCUSSION

We review the differential diagnosis and recommended workup for posterior circulation stroke in children. The anatomical cause for pediatric RVAO is most commonly an anomalous bone formation of the rostral vertebral column. Many bony anomalies have been associated with RVAO, including the "ponticulus posticus," a common anomaly of the C1 vertebrae. The definitive diagnosis of RVAO is made with dynamic angiography, and surgical decompression of the vertebral artery prevents recurrent strokes.

ILLUSTRATIVE CASE

We report a 15-year-old boy with recurrent posterior circulation ischemic strokes caused by an anomalous ossification of the C1 vertebrae. Three-dimensional (3D) and multiplanar reconstructed CT images showed the anomalous C1 ossification, and cervicocerebral digital subtraction angiography (DSA) revealed an associated vertebral artery (VA) dissection. The patient was initially managed by head immobilization in a hard collar and anticoagulation for 3 months. After healing of the dissection that was confirmed angiographically, dynamic DSA demonstrated reversible occlusion of the VA during contralateral head turn. Surgical decompression of the VA was performed and confirmed by intra-operative DSA with head turning.

CONCLUSIONS

RVAO is an important diagnosis in children with posterior circulation stroke. Our case demonstrates the need for high clinical suspicion and careful analysis of 3D cervical spine CT images in children with posterior circulation stroke.

Bow Hunter's Stroke Caused by a Severe Facet Hypertrophy of C1-2

Bow hunter's stroke is a rare symptomatic vertebrobasilar insufficiency in which vertebral artery (VA) is mechanically occluded during head rotation. Various pathologic conditions have been reported as causes of bow hunter's stroke. However, bow hunter's stroke caused by facet hypertrophy of C1-2 has not been reported. A 71-year-old woman presented with symptoms of vertebrobasilar insufficiency. Spine computed tomography showed massive facet hypertrophy on the left side of C1-2 level. A VA angiogram with her head rotated to the right revealed significant stenosis of left VA. C1-2 posterior fixation and fusion was performed to prevent serious neurologic deficit from vertebrobasilar stroke.

Positional vertebral artery compression and vertebrobasilar insufficiency due to a herniated cervical disc

The authors report a case of vertebrobasilar insufficiency caused by vertebral artery (VA) compression due to a herniated cervical disc, which was surgically treated with the aid of intraoperative angiography. This 78-year-old man visited the hospital because of syncope following head rotation. Admission CT scans revealed a calcified mass adjacent to the right lateral process of the C-4 spine. Cervical angiography demonstrated an obstruction of the right VA at this region on rotation of the head to the right. The operation revealed a cervical disc protruding toward the right VA. The disc was surgically removed, and then the decompression of the right VA was confirmed on intraoperative angiography studies. A histopathological examination showed fibrohyaline cartilage, indicating an ossified intervertebral disc. The postoperative course was uneventful, and he has not experienced any syncope since treatment. A cervical disc herniation could be a cause of vertebrobasilar insufficiency by exerting positional compression of the VA. Intraoperative angiography could be quite useful to confirm this condition during decompression surgery for a cervical VA.

Minimally invasive decompression of a suboccipital osseous prominence causing rotational vertebral artery occlusion. Case report

Surgical decompression of the vertebral artery (VA) between the suboccipital area and C-1 is typically performed via a large midline incision or a far-lateral approach. Such traditional open approaches are often associated with significant muscle dissection and blood loss. In this case, a 12-year-old boy suffered a stroke related to a VA rotational occlusion (bow hunter syndrome) and dissection due to a prominent suboccipital bone mass. Successful decompression of the VA was performed via a minimally invasive 22-mm tubular retractor. This is the first reported case report of a minimally invasive decompression of the VA between the skull base and C-1.

Rotational vertebrobasilar ischemia due to vertebral artery dynamic stenoses complicated by an ostial atherosclerotic stenosis

Abstract

We describe a patient with rotational vertebrobasilar ischemia (RVBI) due to vertebral artery (VA) compressive stenoses during neck rotation, complicated by an ostial atherosclerotic stenosis (OAS). Referred for ‘near-syncopal spells’, inquiry revealed a symptom-complex consistent with vertebrobasilar transient ischemic attacks (TIAs) provoked by head rotation. VA dynamic angiography with imaging via prevertebral subclavian injections in neck-rotated positions while reproducing symptoms, demonstrated two compressive stenoses not present in the neck-neutral position, establishing the diagnosis of RVBI due to CT-demonstrated cervical spondylosis. There was an occluded contralateral VA, isolated posterior circulation, and absent vertebral collateral flow. Disabling symptoms persisted despite using a cervical collar. Surgical decompression of the dynamic stenoses would not address the OAS, was considered high risk, and absence of a suitable donor artery precluded distal VA reconstruction. RVBI resolved with ostial stent placement by improving perfusion pressure across the compressive stenoses. To our knowledge, this is the first report of RVBI in which the affected VA had an obstructive atherosclerotic stenosis in addition to the characteristic rotation-induced dynamic stenoses, and the first report of stent placement in the culprit artery to treat this disorder. Diagnosis depends on recognizing the association of symptoms with positional neck changes and VA dynamic angiography demonstrating the compressive stenosis while reproducing symptoms. This case illustrates the management complexities when there are coexisting abnormalities, emphasizing the need to individualize treatment. RVBI is a potentially correctable cause of TIAs and particularly relevant due to the aging population which has a significant incidence of both degenerative cervical and atherosclerotic cerebrovascular disease.

Atypical suboccipital vertebral artery blood flow in healthy subjects: case studies using real-time ultrasound

Manual therapists and other professionals are using real-time ultrasound increasingly to visualize vessels and determine their diameter and blood flow. Four case studies are presented to show atypical ultrasound profiles of the suboccipital vertebral artery (VA3) in healthy, young individuals. VA3 diameters and blood flow velocities were measured with the subjects sitting, and the cervical spine in the neutral position then with active, full-range rotation to the left and right. None of the subjects reported any signs or symptoms of vertebrobasilar ischemia (VBI) during the measurement procedure, despite an absence of typical VA3 ultrasound profiles on one side in two of the individuals and a decreased unilateral VA3 blood flow in the other two subjects. Possible reasons for the atypical findings are proposed. Anatomical variations of VA3 and conditions such as obesity may give rise to atypical real-time ultrasound measurements of VA3 blood flow, particularly when associated with cervical spine rotation. The possibility of altered VA3 blood flow because of such factors, which may give rise to false-positive or false-negative findings in the standard VBI test, should be considered by manual therapists in pretreatment assessments and treatment programs in professional practice.

Subaxial positional vertebral artery occlusion corrected by decompression and fusion

STUDY DESIGN

A rare case of subaxial vertebral artery (VA) positional occlusion is reviewed and treatment methods discussed.

OBJECTIVE

The decision process involved in treating subaxial VA positional occlusion is reviewed.

SUMMARY OF BACKGROUND DATA

Bow Hunter stroke is a symptomatic vertebrobasilar insufficiency caused by stenosis or occlusion of the VA with physiologic head rotation. It most commonly occurs at the junction of C1 and C2 and less commonly as the VA enters the C6 transverse foramen. Rotational stenosis of the VA is quite rare during its passage through the foramen transversarium of C3-C6.

METHODS

A 48-year-old gentleman presented describing syncopal episodes when he turns his head to the left side. Imaging revealed a congenitally narrowed right foramen transversarium and high-grade stenosis of the left VA when the head was turned to the left. A routine anterior cervical discectomy and fusion was performed with the addition of decompression of the left transverse foramen.

RESULTS

Vascular imaging should be performed with the patient's head in both the neutral position and in the symptomatic position. Surgical treatment may be chosen if conservative therapies fail and generally has 1 of 2 goals-decompression of the VA or elimination of rotational movement at the affected level. Decisions between anterior and posterior decompressions may be influenced by the surgeon's comfort level with the approach and if the transverse foramen stenosis is caused mainly by an anterior (osteophytes at the uncinate process) or posterior (facet joint hypertrophy) process. The patient remains symptom-free after treatment.

CONCLUSION

This report demonstrates the condition in the subaxial spine and describes successful treatment by fusion of the affected level combined with decompression of the foramen transversarium-a combination of previously described therapies.

Simultaneous bilateral vertebral artery occlusion in the lower cervical spine manifesting as bow hunter's syndrome

A 59-year-old male had suffered near-syncopal episodes for more than one year that occurred immediately on turning his head to the left. Cerebral magnetic resonance (MR) imaging did not detect any contributing lesions with well-developed posterior communicating arteries. Dynamic radiography of the cervical spine showed mild instability at C5-6 and concomitant intramedullary hyperintensity confirmed by T(2)-weighted MR imaging. Cervical computed tomography demonstrated an osseous protrusion in the right foramen transversarium at C5. Dynamic cerebral angiography revealed simultaneous vertebral artery (VA) occlusion at C6 on the right and C5 on the left associated with leftward head rotation. The VA showed an intact course at the C1 to C2 levels. The patient underwent anterior fusion followed by decompressive foraminotomy at C5-6 and C6-7 and meticulous resection of the markedly thickened fibroligamentous structure which was considered to contribute to the rotational VA occlusion. Postoperatively he no longer suffered near-syncope during head rotation. Bow hunter's syndrome is an infrequent type of vertebrobasilar insufficiency that may need surgical management for potential threat of ischemic stroke. Simultaneous VA occlusion at the lower cervical level can cause bow hunter's syndrome. Dynamic cerebral angiography is a useful modality for evaluating bow hunter's syndrome even if the patient cannot tolerate dynamic examination for the immediate symptom. Accurate anatomical knowledge of the uncovertebral foraminal region combined with intraoperative dynamic study is essential for safe surgery to the VA and favorable outcome.

Anterior vertebral artery decompression with an ultrasonic bone curette to treat bow hunter's syndrome

We report a patient with bow hunter's syndrome who was treated by anterior decompression of the vertebral artery (VA) using an ultrasonic bone curette (SONOPET). This 60-year-old man reported almost losing consciousness upon head rotation. Although the right VA appeared normal at the natural head position, upon left head rotation it became completely occluded at the transverse foramen of C2. We performed anterior decompression of the right VA at the axis using a high-speed drill and SONOPET. For anterior decompression of the VA in a deep and narrow operative field, we recommend use of SONOPET, which permits safe, easy bone dissection.

“Stretched loop sign” of the vertebral artery: a predictor of vertebrobasilar insufficiency in atlantoaxial dislocation

BACKGROUND

Vertebrobasilar territory infarction is one of the rarer presentations of CVJ anomalies. A new radiologic sign due to stretching of the short third segment of VA detected on MRA/DSA may identify patients of AAD at risk of developing VBI.

METHODS

Seven patients who presented with VBI were found to have a coexisting mobile (n = 6) or fixed (n = 1) AAD. None of these patients had the presence of any of the known risk factors for cerebrovascular disease. On identification of VBI on CT/MRI, DSA (n = 7) and MRA (n = 1) were performed to assess bilateral vertebral arteries. The course of normal VA was also studied in 5 control patients without AAD or VBI.

RESULTS

Digital subtraction angiography/MRA showed obstruction of VA at the C1 through C2 level on one side in each of these cases. The third segment of the contralateral VA showed a shortened and straighter loop termed as the stretched loop sign of the VA. On DSA, the latter manifested as (a) opening of the distal loop of the VA as it emerges from the foramen transversarium of the atlas and traverses on the dorsum of the posterior arch of atlas (n = 3), (b) shortened and stretched VA that runs laterally and posteriorly forming the proximal loop after emerging from the foramen transversarium of the axis (n = 2), or (c) both (n = 2). All patients presented with the clinical manifestations of VBI. Only 2 of these had preexisting myelopathy and long tract signs conventionally attributable to AAD.

CONCLUSION

Vertebrobasilar territory infarction in AAD may occur because of the obstruction of the third segment of VA. A shorter and straighter loop of the third segment of VA coexisting with an abnormal translational mobility between the atlas and the axis may be the etiopathogenetic factor.

Rotational vertebrobasilar ischemia: hemodynamic assessment and surgical treatment

OBJECTIVE

Rotational vertebrobasilar insufficiency is a severe and incapacitating condition. Proper investigation and management are essential to reestablish normal posterior circulation hemodynamics, improve symptoms, and prevent stroke. We present a series of 10 patients with rotational vertebrobasilar ischemia who were treated surgically and emphasize the importance of transcranial Doppler in the diagnosis and management of this condition.

METHODS

All patients presented with symptoms of vertebrobasilar insufficiency induced by head turning. Transcranial Doppler documented a significant decrease in the posterior cerebral artery velocities during head turning that correlated with the symptoms in all patients. A dynamic cerebral angiogram was performed to demonstrate the site and extent of vertebral artery compression.

RESULTS

The surgical technique performed was tailored to each individual patient on the basis of the anatomic location, pathogenesis, and mechanism of the vertebral artery compression. Five patients underwent removal of osteophytes at the level of the subaxial cervical spine, one patient had a discectomy, two patients had a decompression only at the level of C1-C2, and two patients had a decompression and fusion at the C1-C2 level.

CONCLUSION

The transcranial Doppler is extremely useful to document the altered hemodynamics preoperatively and verify the return of normal posterior circulation velocities after the surgical decompression in patients with rotational vertebrobasilar ischemia. Surgical treatment is very effective, and excellent long-term results can be expected in the vast majority of patients after decompression of the vertebral artery.

The vertebral artery: a review of anatomical, histopathological and functional factors influencing blood flow to the hindbrain

An uncompromised blood flow to the brain is essential for normal neurological function. If the blood supply to the hindbrain, via the paired vertebral arteries, is reduced sufficiently, signs and symptoms of tertebrobasilar ischaemia may result. There are several factors that may cause a reduction in vertebral artery blood flow. These include exostoses, such as the retroarticular canal and lateral bridge of the atlas vertebra that may cause compression of the related part of the vertebral artery; or atherosclerosis of the artery wall occluding the vessel lumen. Functional factors, such as sustained end-of-range rotation of the cervical spine, may cause distortion of the vertebral artery in the suboccipital region, which may be reflected as decreased blood flow in the suboccipital and intracranial parts of the artery. A combination of such factors is likely to cause reduced blood flow to the hindbrain. It is the purpose of this review to highlight some of the factors that may compromise vertebral artery blood flow and, therefore, to provide some evidence on which to base our professional practice.

Rotational vertebral artery occlusion from occipital bone anomaly: a rare cause of embolic stroke. Case report

Vertebral artery (VA) occlusion by rotation of the head is uncommon, but can result from mechanical compression of the artery, trauma, or atlantoaxial instability. Occipital bone anomalies rarely cause rotational VA occlusion, and patients with nontraumatic intermittent occlusion of the VA usually present with compromised vertebrobasilar flow. A 34-year-old man suffered three embolic strokes in the vertebrobasilar system within 2 months. Magnetic resonance imaging demonstrated multiple infarcts in the vertebrobasilar territory. Angiography performed immediately after the third attack displayed an embolus in the right posterior cerebral artery. Radiographic and three-dimensional computerized tomography bone images exhibited an anomalous osseous process of the occipital bone projecting to the posterior arch of the atlas. Dynamic angiography indicated complete occlusion of the left VA between the osseous process and the posterior arch while the patient's head was turned to the right. Surgical decompression of the VA resulted in complete resolution of rotational occlusion of the artery. An occipital bone anomaly can cause rotational VA occlusion at the craniovertebral junction in patients who present with repeated embolic strokes resulting from injury to the arterial wall.

Uneventful upper cervical manipulation in the presence of a damaged vertebral artery

OBJECTIVE

To discuss a case in which a patient with a previously injured vertebral artery underwent manipulation in the upper cervical spine without alteration of her symptom pattern. The literature concerning the relative safety of specific upper cervical manipulative techniques is reviewed.

CLINICAL FEATURES

A 42-year-old woman had a 3-week history of unilateral suboccipital pain that she related to a sudden twisting of her head and neck that occurred while she was putting sheets of drywall on top of her car. Subsequent examination by a neurologist 2 weeks later was unremarkable, and a tension-type headache was diagnosed. Approximately 10 days later (3 weeks after injury), a single high-velocity upper-cervical manipulation (incorporating slight rotation and full lateral flexion) was performed with no change in her symptom pattern. Two weeks after that, the patient had development of a lateral medullary syndrome (also known as Wallenberg syndrome) after she briefly extended and rotated her upper cervical spine while painting a ceiling.

INTERVENTION AND OUTCOME

The patient was treated with anticoagulant therapy, and the lateral medullary infarct healed without incident. The spinocerebellar and subtle motor symptoms also resolved, but the ipsilateral suboccipital headache and the loss of temperature sensation associated with the spinothalamic tract lesion were still present 9 months later.

CONCLUSION

This case report demonstrates that vigorous manipulation of the upper cervical spine is possible without injuring an already damaged vertebral artery. It is suggested that the line of drive used during the single manipulation, almost pure lateral flexion with slight rotation, was responsible for the apparent innocuous response. Guidelines for the evaluation and management of vertebral artery dissection are reviewed. Because it is currently impossible to identify patients at risk of having a dissected vertebral artery with standard in-office examination procedures, rotational manipulation of the upper cervical spine should be abandoned by all practitioners, and schools should remove such techniques from their curriculums.

Bow hunter stroke caused by cervical disc herniation. Case report

Bow hunter stroke, which is characterized by transient vertebrobasilar ischemia brought on by head turning, is an unusual condition usually caused by structural abnormalities at the craniocervical junction. The authors present a case in which compression of the left vertebral artery (VA) at the C4-5 level was caused by a laterally herniated intervertebral disc. A 56-year-old man presented with a 6-month history of dizziness and syncope when he turned his head 45 degrees or more to the left. Transcranial Doppler (TCD) ultrasonography demonstrated decreased blood flow through the left VA, and angiography revealed an occlusion of the left VA at the C4-5 level, both when the patient turned his head to the left. Via an anterior cervical approach, the VA canal was unroofed through the transverse foramina to decompress the left VA at C4-5; intraoperatively, the left VA was found to be compressed by a laterally herniated cervical disc fragment. To the best of the authors' knowledge this is the first report of a laterally herniated cervical disc causing bow hunter stroke. The use of TCD may be of value in the diagnosis and management of the disorder, and herniated cervical disc must be included in the roster of potential causes for this rare disease.

Anterior decompression of the atlantoaxial vertebral artery to treat bow hunter's stroke: technical case report

OBJECTIVE AND IMPORTANCE

Bow hunter's stroke is a symptomatic vertebrobasilar insufficiency caused by stenosis or occlusion of the vertebral artery at the C1C2 level with head rotation. No case of anterior decompression of the vertebral artery for surgical treatment of bow hunter's stroke has been reported.

CLINICAL PRESENTATION

A 47-year-old male patient presented with repeated episodes of unconsciousness caused by turning his head approximately 40 degrees to the right; he recovered consciousness within approximately 10 seconds after his head was returned to the neutral position. Angiography revealed an occluded right vertebral artery and temporary occlusion of the left vertebral artery, at the level of the C2 transverse foramen, when the patient's head was turned approximately 40 degrees to the right.

INTERVENTION

Anterior decompression of the left vertebral artery at the transverse foramen of the axis was performed. Postoperative angiography demonstrated sufficient flow in the left vertebral artery even when the neck was rotated.

CONCLUSION

The patient was discharged without neurological deficits. We demonstrate that simple surgical untethering of the vertebral artery at the transverse foramen of the axis is an effective method of treatment that avoids the limitation of head rotation. The advantage of this procedure is that it does not result in postoperative restriction of the patient's neck movements. The anterior approach, with decompression of the transverse foramen of the axis, in the present case provided adequate exposure of the vertebral artery and resulted in a satisfactory outcome.

Rotational compression of the vertebral artery at the point of dural penetration. Case report

Vertebrobasilar insufficiency (VBI) due to vertebral artery (VA) compression occurs in a significant number of patients. Rotational compression of the VA usually occurs below C-2, where the artery is pinched during head rotation, leading to thrombus formation and subsequent cerebellar infarction. Although this problem has been reported to occur at the atlantooccipital levels, a review of the literature revealed no published cases of VA compression at the point of dural penetration, which is located above the atlantooccipital membrane. The authors report the case of a 30-year-old woman who presented with signs and symptoms of VBI. Dynamic angiography demonstrated left-sided VA compression at the site at which dural penetration had occurred, proximal to the posterior inferior cerebellar artery. Surgical decompression of the left VA at the point of dural penetration relieved the symptoms, and postoperative dynamic angiography demonstrated complete resolution of the positional compression of the left VA. Because of these findings, an additional possible location for rotational compression of the VA is described, namely, the point of dural penetration. The authors suggest a method of surgically treating rotational VA compression at this site.

Bow Hunter's stroke caused by a nondominant vertebral artery occlusion: case report

OBJECTIVE AND IMPORTANCE

Bow hunter's stroke is a consequence of vertebrobasilar insufficiency as a result of mechanical occlusion or stenosis of the vertebral artery at the C1-C2 level by head rotation. In most cases, a dominant vertebral artery is involved. No case of bow hunter's stroke as a result of mechanical occlusion of a nondominant vertebral artery has ever been reported.

CLINICAL PRESENTATION

We describe a rare case of Wallenberg's syndrome caused by occlusion of a nondominant vertebral artery induced by head rotation. The patient complained of vertigo and paresthesia of the left face and the right extremities when he rotated his head 45 degrees or more to the right.

INTERVENTION

Dynamic angiography revealed that the left vertebral artery was smaller than the right, terminated in a branch of the posteroinferior cerebellar artery, and was stretched and completely occluded at the C1-C2 level with the head rotated 45 degrees to the right. The right vertebral artery was normal when the head was rotated to either the right or the left. Three-dimensional enhanced computed tomography with the head rotated 45 degrees to the right revealed that the left vertebral artery was stretched and occluded by dislodgment between C1 and C2. Cerebral blood flow scintigraphy with head rotation demonstrated that blood flow was decreased in the lower portion of the left cerebellar hemisphere. C1-C2 posterior fixation was performed to prevent life-threatening neurological accidents.

CONCLUSION

We emphasize that the diagnosis of bow hunter's stroke should be based not only on angiographic findings but also on hemodynamic studies with head rotation.

Rotational vertebral artery occlusion: a mechanism of vertebrobasilar insufficiency

OBJECTIVE

Symptomatic dynamic changes in blood flow secondary to vertebral artery compression with rotational head motion are evaluated in a series of patients as a cause for posterior circulation transient ischemic attacks. These cases are classic examples of rotational vertebral artery occlusion and allow for the discussion of the anatomic basis, angiographic features, and treatment options.

ILLUSTRATIVE CASES

In our series, symptoms of vertebrobasilar insufficiency were reproducible with rotational head movement. Compression of the vertebral artery was demonstrated angiographically. The correct site of occlusion of the vertebral artery was apparent only by dynamic angiography with progressive head rotation. All of the patients presented in the illustrative cases had occlusion at the C2 level; however, one patient had been previously misdiagnosed and another had an additional site of occlusion. The anatomic course of the vertebral artery is described in addition to the sites of rotational occlusion.

CONCLUSION

Rotational vertebral occlusion is an important cause of vertebrobasilar symptoms, which may lead to permanent neurological deficit if left undiagnosed. Dynamic angiography is the established method of diagnosis. Great care must be taken to avoid misdiagnosing the site of occlusion or missing a second occlusive site. For this reason, it is crucial to have a thorough understanding of the anatomic course of the vertebral artery and the muscular and tendinous insertions, which may cause rotational occlusion. The decision for treatment must be based on the site of occlusion as well as the assessment of the patient as a surgical candidate. A review of the literature reveals that surgical treatment is effective and must be considered to avoid further morbidity.