A novel sling technique for microvascular decompression of a rare anomalous vertebral artery causing cervical radiculopathy

Anterior artery release, distraction and fusion (ARDF) for radiculopathy caused by a vertebral artery loop

BACKGROUND

Anomalous vertebral artery (VA) with loop formation is a rare cause of cervical nerve root compression. Various techniques with anterior and posterior approaches have been described for surgical treatment once conservative treatments fail. We herein present a case treated with the new technique of anterior release, distraction and fusion (ARDF) and further provide an updated review of surgically managed VA loops in the subaxial spine.

CASE DESCRIPTION

A 76-year-old female complained of a 6-year history of pulsating, shooting pain in her right arm to the thumb. After obtaining repeated MRI, the VA loop compressing the right-sided C6-nerve root was detected. A neurovascular decompression through ARDF which led to an indirect loop straightening was performed. The patient immediately improved after surgery and remained pain-free 1 year postoperative.

CONCLUSION

Neural irritation due to VA loop formation is a rare cause of cervical radiculopathy. While various surgical strategies have been described, we believe that anterior and anterolateral approaches are the safest to yield neurovascular decompression. We described and documented ARDF (anterior VA release, intervertebral distraction and fusion) on a patient case.

LEVEL OF EVIDENCE

II (Diagnostic: individual cross-sectional studies with consistently applied reference standard and blinding).

Vertebral Artery Transposition and Dural Ring Reconstruction: A New Treatment Modality for Cervical Spinal Cord Compression Resulting From Aberrant Vertebral Arteries

BACKGROUND

Two of three patients who were consecutively treated within the past 7 years using traditional methods in our center presented with recurrence and even aggravation during follow-up. Therefore, a new approach was developed to treat a recent patient to provide for complete decompression of the spinal cord.

OBJECTIVE

To illustrate a new treatment modality for patients with cervical spinal cord compression resulting from aberrant vertebral arteries.

METHODS

The aberrant vertebral arteries were freed after substantial dissection of their dural rings. The compression was released after moving the aberrant vertebral arteries, which were sutured to the lateral mass to the extradural space. New dural rings above the atlas were created to allow the vertebral artery to enter the dura mater into a wider subdural space.

RESULTS

The patient experienced full relief from her initial complaints except for mild numbness of the bilateral lower extremities immediately after surgery. Postoperative imaging studies indicated successful transposition of bilateral aberrant vertebral arteries and significant decompression of the spinal cord. Her symptoms did not recur over a 6-month follow-up period. Imaging studies at the 6-month follow-up showed stable vertebral artery transposition and spinal cord decompression.

CONCLUSION

A patient with cervical spinal cord compression resulting from aberrant vertebral arteries was successfully treated by our new technique, which includes vertebral artery transposition, fixation, and dural ring reconstruction. Our approach could be an alternative for durable spinal cord decompression in such patients.

Surgical Interventions for Cervical Radiculopathy Caused by a Vertebral Artery Loop: A Case Report and Review of the Literature

BACKGROUND

Aberrant vertebral artery loops are a rare clinical condition, with sparse data regarding the optimal treatment guidelines for individual patients. The heterogeneity of treatment options in the literature creates a problem when tailoring treatments to individual patients. In this review of the literature, multiple surgical treatments for cervical vertebral artery loops were analyzed and compared. In addition, this article provides a clinical case of a patient with a vertebral artery loop.

METHODS

A literature review was conducted to identify studies investigating surgical treatments for a vertebral artery loop. Different surgical techniques were examined and the involved techniques and approaches described. The outcomes were assessed for each study and the effectiveness of the treatment determined.

RESULTS

Twelve articles met the inclusion criteria for this review. Six types of surgical interventions were found in the literature. Each intervention had similar postoperative results, leading to either a significant improvement or a complete resolution of symptoms.

CONCLUSIONS

Multiple successful surgical interventions have been described in the medical literature. However, because of the lack of evidence-based studies, no surgical intervention protocol could be determined. Treatment should therefore be tailored to individual patients' characteristics. Because not every radiologically detected vertebral artery loop is the main reason for a patient's symptoms, a thorough multidisciplinary approach is justified and advocated in patients with an atypical presentation, before a neurosurgical intervention takes place. More deliberate clinical decisions can be made once the understanding of the pathogenesis of this rare disease entity has been established and treatment protocols formulated.

Vertebral Artery Sacrifice: Novel Strategy in Treatment of Vertebral Artery Loop

BACKGROUND

We report a case of cervical radiculopathy caused by an anomalous vertebral artery (VA) and the efficacy of endovascular vertebral artery sacrifice.

CASE DESCRIPTION

A 62-year-old woman was referred to neurosurgery because of an 8- to 9-year history of progressive left C6-7 radiculopathy refractory to other forms of treatment. Radiologic evaluation showed an abnormally tortuous loop of VA at V2 causing direct neurovascular compression at the C6-7 level. Initial attempts at microvascular decompression with posterior foraminotomy were unsuccessful due to strong adhesion between the VA and C7 nerve root. This was followed by an endovascular VA sacrifice relieving the patient's symptoms.

CONCLUSIONS

Cervical root compression by an aberrant or anomalous extracranial VA is a rare cause of radiculopathy. Endovascular VA sacrifice provided symptom relief in our patient, when other options failed. To our knowledge, this is the first report of endovascular VA sacrifice for management of cervical radiculopathy due to VA loop.

Anterolateral Approach for a Cervical Nerve Root Compression Syndrome Due to an Ectatic Vertebral Artery

BACKGROUND AND IMPORTANCE

Nerve root compression by an ectatic vertebral artery is a known but easily overlooked cause of cervical radiculopathy. Management options include nonoperative conservative therapies or surgical approaches designed to relieve the compression via anterior or posterior cervical approaches.

CLINICAL PRESENTATION

A 72-yr-old female presented with a 6-mo history of sharp, shooting pain in her right arm and shoulder and deltoid weakness. Imaging demonstrated a vertebral artery loop compressing the proximal right C5 nerve root. She previously underwent both nonoperative measures as well as posterior foraminotomy at this level with limited improvement in her pain. Therefore, we performed an anterolateral approach for vascular decompression of the C5 nerve root from the vertebral artery loop. Patient has been pain-free at 1 yr with full recovery of her deltoid weakness.

CONCLUSION

Vertebral artery loop formation is an uncommon cause of cervical radiculopathy, which can be readily treated by vascular decompression of the nerve root-vertebral artery loop complex. Although anomalous vertebral artery compression of a cervical nerve root is rare, it is increasingly being recognized as a readily treatable entity that can lead to lasting and full neurological recovery. We also include an operative video to illustrate the vascular decompression of an ectatic vertebral artery causing severe cervical radiculopathy.

Cervical Myelopathy Due to Direct Cord Compression by Posterior Inferior Cerebellar Artery Associated with Aberrant Vertebral Artery

BACKGROUND

The effectiveness of surgical microvascular decompression (MVD) of the vertebral artery (VA) for treating conditions such as trigeminal neuralgia or hemifacial spasm is well known. However, the use of MVD for a case in which the posterior inferior cerebellar artery (PICA) is directly compressing the high cervical cord has not been reported.

CASE DESCRIPTION

A 48-year-old male was diagnosed with a rare case of myelopathy due to the PICA directly compressing the high cervical cord. The patient had a C-2 segmental type of VA that penetrated the intradural space at the C1 level. The VA-PICA portion was located just after where the intradural space was penetrated, and the branching PICA strongly and vertically compressed the high cervical cord.

CONCLUSIONS

MVD of the PICA was performed, and the patient experienced rapid improvement of myelopathy. The patient immediately improved postoperative day 1 and was doing well at his 1-year follow-up. This is a rare case of the PICA directly compressing the cervical cord and causing myelopathy. MVD of the PICA resulted in good patient recovery.

A New Sling Technique in Cervical Radiculopathy Caused by Vertebral Artery Loop Compression

BACKGROUND

A 52-year-old woman had a 20-month history of progressive radiating pain in the left arm and numbness on C7 dermatome.

CASE DESCRIPTION

On physical examination, left head rotation aggravated the radiculopathic pain. For an anatomic diagnosis of the vertebral artery and nerve root, magnetic resonance angiography was performed (computed tomography angiography was not possible because of her dye allergy history). Magnetic resonance angiography showed a left vertebral artery loop entering at the C6-7 intervertebral foramen. Surgical microvascular decompression was performed by an anterior cervical approach and the loop of the artery was fixed using a sling technique. Postoperative computed tomography angiography showed that the left vertebral artery was retracted anteriorly and the C7 nerve root was decompressed in the intervertebral foramen at the left C6-7 level.

CONCLUSIONS

The patient's radiculopathic symptoms were improved and especially the aggravated pain by left head rotation subsided dramatically.

Anterior Transposition of Anomalous Tortuous Vertebral Artery Causing Cervical Radiculopathy: A Report of 2 Cases and Review of Literature

OBJECTIVE

Cervical radiculopathy secondary to compression from vertebral artery (VA) tortuosity is a rare entity. We describe successful transposition through an anterolateral approach of tortuous VA loops causing cervical radiculopathy.

METHODS

Two patients with cervical radiculopathy (first case at C5-6 and second case at C3-4) secondary to anomalous VA loop compression underwent anterolateral approaches to the cervical spine for decompression and VA transposition. The anterior transverse foramina were drilled to unroof the VA loop, which was dissected free from the exiting nerve root.

RESULTS

In both cases, the affected cervical nerve root was successfully decompressed with both radiographic and clinical improvements in radiculopathy symptoms. We found 8 other cases of VA transposition via either an anterolateral approach or a posterolateral approach described in the literature. Our second case of anterolateral VA transposition at the C3-4 level is the first case at this level and the highest level reported in the literature.

CONCLUSIONS

Decompression using an anterolateral approach with direct microvascular transposition of the VA is a safe and effective treatment of this pathology and addresses the cause of radiculopathy more directly than the posterolateral approach.

Vertebral artery loops in surgical perspective

PURPOSE

Vertebral artery loop is a congenital or acquired anomaly. Vertebral artery loops are incidentally diagnosed during evaluation of neck problems and trauma. We aimed to present the incidence of VA loops using magnetic resonance angiography in consecutive patients and discuss epidemiological data including the gender, age, location, signs and symptoms, treatment approaches and outcomes of VA loops via analyzing literature.

METHODS

In the first leg of our two-legged study, consecutive patients were evaluated using magnetic resonance angiography to detect any medial loop of vertebral arteries. The study period was from October 2015 to March 2016. In the second leg, academic databases about medial loop of vertebral artery were screened. Case reports, case series, abstracts and references of relevant literature were searched manually to avoid any missing cases.

RESULTS

We evaluated 239 consecutive patients using magnetic resonance angiography. Twenty-one patients were excluded from the study due to inadequate image acquisition, aplastic vertebral artery and/or concomitant vertebral artery stenosis. Medial loop of V2 vertebral artery was observed in 13 patients (5.9 %): 9 with left, 2 with right and 2 with bilateral medial V2 loop. Patients with medial V2 loop were significantly older than patients with straight vertebral arteries (70.30 vs. 62.36, p = 0.028). In the literature analysis, VA loops were more commonly observed at V2 segment (90.5 %). Vertebral artery loops were mostly diagnosed at the 5th and 6th decades of life predominantly in females. The most common signs and symptoms were radiculopathy and/or neck pain, and signs and symptoms of vertebrobasilar insufficiency.

CONCLUSIONS

Concise pre-operative evaluation of the vertebral arteries is essential to avoid the injury of undiagnosed VA loops during surgery, which might result in catastrophic circumstances. Further evaluation of the vertebral arteries using MR angiography is required, especially in elder age, before cervical spine surgeries.