Vertebral artery loops in surgical perspective

Potential causes of iatrogenic intraoperative bleeding during C1 surgeries: a CT 3D rendering study

BACKGROUND

Iatrogenic intraoperative bleeding during C1 surgeries is difficult to manage.

PURPOSE

To investigate the potential causes of iatrogenic intraoperative bleeding in atlas surgeries.

STUDY DESIGN

This was a retrospective study, observational cohort of patients with DICOM.

PATIENT SAMPLE

High-resolution head and neck computed tomography angiography (CTA) images from 551 subjects were included.

OUTCOME MEASURES

Ponticulus posticus (POPO), vertebral artery (VA), venous plexus communication.

METHODS

Three dimension rendering was utilized in the present study. Potential arterial bleeding was evaluated based on the variation in the VA and the polymorphism of the POPO over the groove for VA (GVA). The communication of the venous plexus in the occipitoatlantal region was investigated to assess the venous hemorrhage.

RESULTS

Among the 551 atlases examined, POPOs were identified on 155 sides, resulting in a prevalence of 14.07% (155/1102). These POPOs (n=155) were reclassified into four types: tiny spur (54.84%), long spur (7.10%), ossified bridge (30.32%), and ossified canal (7.74%). In 42.92% (473/1102) of cases, the VA did not directly contact the sulci of the GVA, creating space for the passage of the rich venous plexus that drained intracranial venous blood outflow to various extracranial layers. Moreover, in 12.7% of the subjects, the study revealed the presence of additional foramens in the posterior lamina of C1, which served as a conduit for the communicating vein CONCLUSION: The potential underestimation of polymorphism in POPOs and VAs can lead to arterial bleeding, whereas a lack of understanding of the intricate condylar emissary venous plexus can result in venous hemorrhage. To mitigate iatrogenic hemorrhage during C1 surgeries, a preoperative HEAD AND NECK CTA is recommended, and heightened caution should be exercised during dissection in the lateral half of the C1 lamina. Furthermore, unknown causes of intraoperative bleeding may arise during the posterior C1 approach; modifications should be considered based on the specific circumstances encountered.

Integrative Korean medicine treatment without surgery for the management of subacute radiating pain attributed to vertebral artery loop formation: A case report and literature review

RATIONALE

Vertebral artery loop formation (VALF) compresses the adjacent cervical nerve root, resulting in cervical radiculopathy at the affected level. Neurosurgical interventions for anatomical separation are typically employed to relieve the symptoms, regardless of their duration. We herein report the management of the subacute symptoms of a rare case of cervical radiculopathy attributed to VALF using integrative Korean medicine (iKM) treatment without surgery.

PATIENT CONCERNS

A 54-year-old male patient presenting with a chief complaint of headache radiating to the posterior cervical and right scapular regions was treated with a 4-day program of inpatient care.

DIAGNOSES

Based on the findings of the cervical spine magnetic resonance imaging, the patient was diagnosed with VALF on the right side at the C3/C4 level.

INTERVENTIONS

He underwent iKM treatment comprising acupuncture, pharmacopuncture, Chuna therapy, and herbal medicine.

OUTCOMES

Significant improvement was noted in the patient's condition (neck pain Numeric Rating Scale scores of 5, 4, and 1; Neck Disability Index scores of 35.56, 20, and 4; and EuroQol 5-dimension index scores of 0.754, 0.787, and 0.862 at admission, discharge, and the 2-month follow-up, respectively; Patient Global Impression of Change scores of 3 and 1 at discharge and the 2-month follow-up, respectively).

LESSONS

This case report suggests that iKM treatment may be effective for subacute VALF symptoms without requiring surgery.

Preventing Iatrogenic Injury to the Vertebral Artery in Cervical Spine Surgery: A Case Report

SUMMARY OF BACKGROUND DATA

Iatrogenic injury of the vertebral artery (VA) in the context of surgical approaches to the cervical spine has been cited as a relatively rare complication with varying degrees of severity ranging from minimal injury to acute stroke and can result in death. It is estimated that ~50% of cases of iatrogenic VA injury are preventable after postoperatively examining a patient's preoperative imaging. Despite the low incidence (<2%) of this complication, the potential associated morbidity demonstrates the importance of meticulous preoperative vascular consideration.

OBJECTIVE

This study aims to emphasize the importance of preoperative vascular screening during anterior cervical access planning visualized through a rare case of a VA aberration in a 47-year-old patient.

STUDY DESIGN

This study is designed as a retrospective case report.

METHODS

A thorough chart review was performed for this subject including all prior medical records, imaging studies, imaging reports, operative notes, and communication records.

RESULTS

The subject was found to have a history of patent foramen ovale (PFO) repair with a rare vertebral artery malformation described as a medial transposition of the vertebral artery out of the vertebral artery foramen between C3 and C4.

CONCLUSIONS

Consideration of cervical anatomy, particularly the VA, is key to minimizing the risk of adverse surgical outcomes in both anterior and posterior approaches to the cervical spine. During the workup process, the patient's primary care providers, radiologists, and surgeons should be aware of the potential variations of the VA with particular attention given to the course of the VA on MR imaging.

LEVEL OF EVIDENCE

Level IV.

Relationship between the Tortuosity of the Extracranial Internal Carotid and Vertebral Arteries on Magnetic Resonance Imaging/Angiography and Vascular Risk Factors in a Japanese Population

Objective We aimed to investigate the relationship between tortuosity of the extracranial internal carotid artery (ICA) or vertebral artery (VA) and vascular risk factors among residents of Asahikawa, northeast Japan. Methods We retrospectively surveyed participants of "brain dock" medical brain checkups, which involved magnetic resonance imaging and angiography. We measured the tortuosity of the ICA and VA, and evaluated vascular risk factors based on medical interviews, questionnaires, and medical records. Results A total of 218 participants were enrolled in the study. ICA tortuosity (right and left) was significantly correlated with age [odds ratio (OR): 2.452, 95% confidence interval (CI): 1.695-3.548, p<0.001]. A more pronounced correlation was observed in females than in males (OR: 1.678, 95% CI: 1.004-2.807, p=0.048). VA tortuosity (right and left) was significantly correlated with age (OR: 1.786, 95% CI: 1.250-2.550, p=0.001) and smoking history (OR: 2.140, 95% CI: 1.235-3.707, p=0.007), and was more pronounced in females than in males (OR: 1.864, 95% CI: 1.107-3.137, p=0.019). Conclusion ICA tortuosity was correlated with age, while VA tortuosity was correlated with age and smoking history. ICA and VA tortuosity were more pronounced in females than in males.

Cervical Radiculopathy and Vertebrobasilar Insufficiency Secondary to Intraneural Foramen Vertebral Artery Loop: A Case Report

This case report describes a 40-year-old male who presented with chronic neck pain radiating to the left upper limb, associated with weakness and numbness. He also had symptoms of vertebrobasilar insufficiency. Imaging revealed an intraneural foramen vertebral artery (VA) loop compressing the C3 nerve root. Conservative management was ineffective, prompting surgical decompression via a left C2-C3 facetectomy and foraminotomy. The patient experienced immediate pain relief and gradual improvement in weakness, with complete resolution of symptoms at the six-month follow-up. This case highlights the potential for VA loops to cause radiculopathy and the successful use of surgical decompression for treatment.

Secondary Benefits of Microsurgical Intervention on the Vertebral Artery (V1 Segment) for Refractory Vertebrobasilar Insufficiency: Alleviation of Parkinsonism-Like Symptoms

OBJECTIVE

The objective of this study was to investigate the outcomes of microneurosurgical interventions on V1 segment of the vertebral artery in patients with refractory vertebrobasilar insufficiency (VBI) due to dolicoarteriopathy and external compressions and to assess the secondary benefits of Parkinsonism-like symptoms.

METHODS

Retrospective analysis encompassed 101 patients treated for vertebral artery dolicoarteriopathy or compression-related refractory VBI from 2016 to 2023. Of these, 16 patients exhibited drug-resistant Parkinsonism-like symptoms. The diagnostic evaluation included cerebral computed tomography/magnetic resonance angiography or digital subtraction angiography and brain computed tomography or magnetic resonance perfusion studies, corroborated by preoperative and 6- and 12-month postoperative Movement Disorder Society-Unified Parkinson's Disease Rating Scale Part 3 assessments. Data were analyzed through Turkey's "E-nabız" system, employing Stata16 for statistical scrutiny.

RESULTS

A significant reduction in Movement Disorder Society-Unified Parkinson's Disease Rating Scale scores was observed (preoperative: 26.75±10.91; 6 months: 23.09±9.24; 12 months: 22.5±8.73; P < 0.001). Postoperative follow-up denoted that 43.7% of patients ceased medication and 50% reduced antiparkinsonian drugs. The microneurosurgical approach resulted in complete remission of VBI-related symptoms in 84.6% of patients, with the rest showing partial or marked improvement. At 6 months postoperation, perfusion studies revealed posterior border zone or cerebellar perfusion enhancements in 81% (13 out of 16) of patients, with full symptom resolution, while the remaining 19% (3 out of 16) showed partial perfusion and clinical improvements, particularly in regions supplied by the posterior cerebellar artery or posterior inferior cerebellar artery. The absence of operative mortality and minimal transient morbidities underscored the procedure's safety.

CONCLUSIONS

Microneurosurgery for vertebral artery anomalies in refractory VBI patients, particularly those with concomitant parkinsonian-like syndromes, has demonstrated potential in symptom remission and medication reduction.

Complementary advantages of microsurgical treatment for vertebral artery dolicoarteriopathies: Mitigating symptoms of restless leg syndrome in refractory vertebrobasilar insufficiency

Objective: This retrospective study examines the impact of microsurgical treatment on vertebral artery (VA) dolicoarteriopathies and associated restless leg syndrome (RLS) in patients with refractory vertebrobasilar insufficiency (VBI). Patients and Methods: We analyzed 78 patients with grade 2 and 3 kinks, and found out that the targeted microsurgical interventions, primarily designed to address VBI, improved secondary RLS symptoms in 12 patients. Procedures included arteriolysis and, depending on severity, grafting. Statistical analysis was conducted using Stata 16 (StataCorp LP, Texas, USA). Results: In twelve patients aged 55 to 72 years with refractory VBI and drug-resistant RLS, micro-neurosurgical correction of V1 segment dolicoarteriopathy, abnormal elongation and kinks in the artery, demonstrated promising outcomes. Postoperatively, 83.33% (10 patients) reported complete resolution of RLS symptoms, and 16.66% (2 patients) experienced partial symptom relief (p&lt;0.05). Overall, 86.8% of various VBI-related symptoms were significantly improved or resolved (p&lt;0.05). The microsurgical technique, avoiding traditional flow-arresting procedures, proved to be highly effective in this preliminary study with no mortality and minimal temporary complications, underscoring its potential treatment avenue for such complex neurovascular conditions. Conclusion: This study illuminates the relationship between VBI and RLS, proposing a potential vascular etiology for RLS, and highlights the need for a broader diagnostic approach for patients with refractory VBI.

Surgical management of tumors of the cervical spine and craniovertebral junction involving the vertebral artery: A narrative review

BACKGROUND

The vertebral artery (VA) is in close proximity to bony structures, nerves and nerve sheaths of the cervical spine and craniovertebral junction (CVJ). These structures can be sources of tumors that are responsible for displacement, encasement and sometimes invasion of the VA. Removing these tumors while minimizing the risk of vascular injury requires thorough knowledge of the vascular anatomy, risk factors of vascular injury, the relationships of each tumor type with the VA, and the different surgical approaches and techniques that result in the best outcomes in terms of vascular control, tumoral exposure and resection.

OBJECTIVE

To present an overview of preoperative and anatomical considerations, differential diagnoses and various approaches to consider in cases of tumors in close relationship with the VA.

METHOD

A review of recent literature was conducted to examine the anatomy of the VA, the tumors most frequently affecting it, surgical approaches, and the necessary pre-operative preparations for ensuring safe and maximal tumor resection. This review aims to underscore the principles of treatment.

CONCLUSION

Tumors located at the CVJ and the cervical spine intimately involved with the VA, pose a surgical challenge and increase the risk of incomplete removal of the lesion. Detailed knowledge of the patient-specific anatomy and a targeted pre-operative work-up enable optimal planning of surgical approach and management of the VA, thereby reducing surgical risks and improving extent of resection.

The Vertebral Artery: A Systematic Review and a Meta-Analysis of the Current Literature

(1) Background. The anatomical variations of the vertebral arteries (VAs) have a significant impact both in neurosurgery and forensic pathology. The purpose of this study was to evaluate the variational anatomy of the vertebral artery. We evaluated anatomical aspects regarding the V1 and V2 segments of the VA: origin, course, tortuosity, hypoplasia, and dominance, and established the prevalence of each variation. (2) Methods. We conducted a systematic search in PubMed and Google Scholar databases, up to December 2022. Sixty-two studies, comprising 32,153 vessels, were included in the current meta-analysis. We used a random-effects model with a DerSimonian-Laird estimator. The confidence intervals were set at 95%. The heterogeneity between studies was assessed using I². The funnel plot and Egger's regression test for plot asymmetry were used for the evaluation of publication bias. Statistical significance was considered at p < 0.05. (3) Results. The most common site for the origin of both VAs was the subclavian artery. The aortic arch origin of the left VA had a prevalence of 4.81%. Other origins of the right VAs were noted: aortic arch (0.1%), right common carotid artery (0.1%), and brachiocephalic trunk (0.5%). Ninety-two percent of the VAs entered the transverse foramen (TF) of the C6 vertebra, followed by C5, C7, C4, and least frequently, C3 (0.1%). Roughly one out of four (25.9%) VAs presented a sort of tortuosity, the transversal one representing the most common variant. Hypoplasia occurred in 7.94% of the vessels. Left VA dominance (36.1%) is more common, compared to right VA dominance (25.3%). (4) Conclusions. The anatomy of the VA is highly irregular, and eventual intraoperative complications may be life-threatening. The prevalence of VA origin from the subclavian artery is 94.1%, 92.0% of the VAs entered the TF at C6, 26.6% were tortuous, and 7.94% were hypoplastic.

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).

Surgical treatment for kyphotic deformity after anterior cervical fusion with a severely tortuous vertebral artery: a case report

We performed salvage surgery on a patient with kyphotic deformity after anterior cervical fusion with a tortuous vertebral artery (VA). A 69-year-old woman had undergone anterior cervical corpectomy and fusion 12 years ago. Her cervical alignment gradually became kyphotic because of bone graft collapse. Ten years after surgery, she experienced severe neck pain, recurrence of myelopathic symptoms and difficulty in keeping her head straight. The patient was diagnosed with rigid cervical kyphosis at C4–6 vertebral levels, with the right tortuous VA invaginating into the C4 vertebral body. We selected a three-stage, anterior–posterior–anterior approach to reduce cervical alignment. The key to a successful surgery in this case was to retract the tortuous VA within the C4 vertebral body, followed by total uncinectomy. Careful preoperative VA evaluation was a decisive factor in surgical planning.

Vertebral Artery Variations at the Craniovertebral Junction in "Sandwich" Atlantoaxial Dislocation Patients

Objective

To summarize the vertebral artery (VA) pattern of 96 “sandwich” atlantoaxial dislocation (AAD) patients and to describe the strategies of reducing the injury of VA during surgery.

Methods

From 2009 to 2020, we retrospectively reviewed the 3-dimensional computed tomography angiography data of 96 AAD patients combined with atlas occipitalization and C2–3 fusion, which were diagnosed as “sandwich” AAD and 96 patients as control group patients who were without atlas occipitalization, C2–3 fusion and any other cervical bone deformity at our institution. The variations of each side of VA were described in 3 different parts (C0–1, C1–2, and C2–3) according to the characteristics of the 3-part pathological structures in “sandwich” subgroup.

Results

One hundred ninety-two sides of VAs in every group of patients were analyzed and every VA was described separately at 3 different level regions. There were different variations in these 3 different regions: 4 variations in the upper fusion region, 5 variations in the sandwiched region, and 6 variations in the lower fusion region in sandwich AAD patients. And the rate of VA deformity in sandwich AAD patients was much higher and more types of VA variations existed.

Conclusion

In “sandwich” AAD patients, deformities of vertebral arteries in craniovertebral junction are more common, and the same VA may have deformities at different levels that severely affect surgical procedures. Therefore, preoperative imaging examination of VA for “sandwich” AAD patients is vital of guiding surgeons to avoid injury of VA during surgery.

Iatrogenic Vascular Injury Associated with Cervical Spine Surgery: A Systematic Literature Review

BACKGROUND

Iatrogenic vascular injury is an uncommon complication of anterior and/or posterior surgical approaches to the cervical spine. Although the results of this injury may be life-threatening, mortality/morbidity can be reduced by an understanding of its mechanism and proper management.

METHODS

We conducted a literature review to provide an update of this devastating complication in spine surgery. A total of 72 articles including 194 cases of vascular lesions following cervical spine surgery between 1962 and 2021 were analyzed.

RESULTS

There were 53 female and 41 male cases (in addition to 100 cases with unreported sex) with ages ranging from 3 to 86 years. The vascular injuries were classified according to the spinal procedures, such as anterior or posterior cervical spine surgery. The interval between the symptom of the vascular injury and the surgical procedure ranged from 0 to 10 years. Only two-thirds of patients underwent intra- or postoperative imaging and the most frequently injured vessel was the vertebral artery (86.60%). Laceration was the most common lesion (41.24%), followed by pseudoaneurysm (16.49%) and dissection (5.67%). Vascular repair was performed in 114 patients. The mortality rate was 7.22%, and 18.04% of patients had 1 or more other complications. Most presumed causes of vascular lesions were by instrumentation/screw placement (31.44%) or drilling (20.61%). Sixteen patients had an anomalous artery. Direct microsurgical repair was achieved in only 15 cases.

CONCLUSIONS

Despite increased anatomical knowledge and advanced imaging techniques, we need to consider the risk of vascular injury as a surgical complication in patients with cervical spine pathologies.

Cervical radiculopathy caused by vertebral artery loop formation: a case report

Vertebral artery loop formation is a rare cause of cervical radiculopathy. We report a case of a 70-year-old man who was referred because of a chronic cervicobrachialgia. Initial plain cervical x-ray showed widening of the left C3-C4 intervertebral foramen. Additional magnetic resonance angiography revealed the presence of a vertebral artery loop, which had migrated into the left C3-C4 neural foramen and caused compression of the left C4 nerve root. Surgery was considered, but the patient’s symptoms resolved with conservative treatment. The aim of this case report is to raise the knowledge of both clinicians and radiologists about vertebral artery loop formation as a rare but potentially life-threatening cause of cervical radiculopathy. If overlooked, cerebrovascular stroke during transforaminal cervical steroid injections or catastrophic vertebral artery damage during surgery may occur.

Intraoperative Computed Tomography Scanner-Guided Craniovertebral Junction Surgery in a Patient with an Occipitalized C1

Craniovertebral junction surgery is associated with unique difficulties. Type 2 odontoid fractures (Anderson and D Alonzo) have a great potential for nonunion and malunion. These fracture patients may require a circumferential decompression and fixation. The addition of intraoperative CT with neuronavigation greatly aids in craniovertebral junction surgery. We operated on a 59-year-old-male with a type 2 fracture with posterior subluxation of C1 anterior arch and a cranially displaced odontoid peg. First, a transoral odontoidectomy was performed followed by a craniocervical fixation. Occipital plates and C3-C4 lateral mass screws were used as C1 was discovered to be occipitalized intraoperatively and atlantoaxial facet joints could not be reduced as discovered by intraoperative CT resconstruction. Intraoperative CT scan was crucial to this circumferential decompression and fixation, allowed us to resect the odontoid peg safely and completely and to confirm adequate screw trajectory making this complex surgery easier for us and safer for the patient. The patient was discharged 4 months after admission with stable neurology. Intraoperative CT was fundamental to correct decision making.

Extraforaminal Vertebral Artery Anomalies and Their Associated Surgical Implications: An Epidemiologic and Anatomic Report on 1000 Patients

OBJECTIVE

Extraforaminal vertebral anomalies involve entry at cervical transverse foramina other than at C6 and can appear with other anatomic variations along the V2 segment. Such unexpected vessel courses can have implications on surgical planning. We sought to evaluate the incidence of anomalous V2 segment entries, as well as their associations with vessel dominance, medialization, and C7 pedicle width.

METHODS

We conducted a retrospective study on 1000 consecutive computed tomography angiograms, documenting level and laterality of vessel of entry, as well as vertebral dominance patterns. Patients with rostral C4 anomalies were assessed for medialization. The pedicle widths ipsilateral to caudal C7 anomalies were compared with those of contralateral and matched controls.

RESULTS

A total of 157 patients were identified with extraforaminal entries, with 25 having bilateral findings. The most common alternative entry was at C5 (70.3%), followed by C4 (17.6%) and C7 (11.5%). Among patients with unilateral anomalies, there was an increased representation of contralateral vertebral dominance, relative to ipsilateral dominance (79.6% vs 20.4%, P < 0.0001). Among anomalous C4 entries, vertebral medialization was seen along the right (35%) and left sides (23.1%) spanning C6-T1. Among C7 anomalous entries there was no statistical difference in pedicle width.

CONCLUSIONS

Extraforaminal anomalies may be more frequent than previously reported and are important considerations during subaxial cervical spine surgery planning. Particular attention should be paid to the contralateral dominance pattern within this subgroup. In patients with anomalous V2 segment entries, adherence to the standard, anatomic landmarks remains desirable.

A Novel and Reproducible Classification of the Vertebral Artery in the Subaxial Cervical Spine

BACKGROUND

An injury of the vertebral artery (VA) is one of the most catastrophic complications in the setting of cervical spine surgery. Anatomic variations of the VA can increase the risk of iatrogenic lacerations.

OBJECTIVE

To propose a novel and reproducible classification system that describes the position of the VA based on a 2-dimensional map on computed tomography angiographs (CTA).

METHODS

This cross-sectional retrospective study reviewed 248 consecutive CTAs of the cervical spine at a single academic institution between 2007 and 2018. The classification consists of a number that characterizes the location of the VA from the medio-lateral (ML) aspect of the vertebral body. In addition, a letter describes the VA location from the anterior-posterior (AP) aspect. The reliability and reproducibility were assessed by 2 independent raters on 200 VAs.

RESULTS

The inter- and intrarater reliability values showed the classification's reproducibility. The inter-rater reliability weighted κ-value for the ML aspect was 0.93 (95% CI: 0.93-0.93). The unweighted κ-value was 0.93 (95% CI: 0.86-1.00) for "at-risk" positions (ML grade ≥1), and 0.87 (95% CI: 0.75-1.00) for "high-risk" positions (ML grade ≥2). The weighted κ-value for the intrarater reliability was 0.94 (95% CI: 0.95-0.95). The unweighted κ-values for the intrarater reliability were 0.95 (95% CI: 0.91-0.99) for "at-risk" positions, and 0.87 (95% CI: 0.78-0.96) for "high-risk" positions.

CONCLUSION

The proposed classification is reliable, reproducible, and independent of individual anatomic size variations. The use of this novel grading system could improve the understanding and interdisciplinary communication about VA anomalies.

Iatrogenic Acute Ischemic Necrosis Due to Emergent Bleeding Control in Ventral Foramen Magnum Meningioma with Spinal Instability

Meningiomas are the most common benign intracranial tumors. They often require surgical resection and postoperative radiation/chemotherapy based on their histologic grade. While necrosis caused by preoperative embolization and spontaneous tumor infarction is appreciated by pathologists when staging meningiomas, intraoperative events including large bore artery occlusion may also alter the histopathologic picture of a benign meningioma. Hence, they should be considered when signs of unexpected ischemia and necrosis are found, as these same phenotypes are also hallmarks of a higher-grade disease. We describe a case of a man with a large ventral foramen magnum meningioma who underwent temporary intraoperative occlusion of the vertebral artery, leading to ischemic tumor necrosis with abundant neutrophil invasion when the tumor was eventually examined histologically.

Cervical Radiculopathy Caused by a Vertebral Artery Loop: Is a Focused Fluoroscopic-Guided Cervical Epidural Steroid Injection a Possible Treatment Modality?

We describe a case of a patient suffering with cervical radiculopathy due to vertebral artery loop with nerve root compression, treated with an epidural steroid injection. A 37-year-old man presented with a 2-year history of right-sided radicular pain along the C7 dermatome. Imaging showed a right-sided loop of the vertebral artery at the V1-V2 transition with contact on the C7 nerve root. The pain was resistant to conservative treatment, and the decision was made to perform a focused fluoroscopy-guided translaminar epidural steroid injection near the C7 nerve root. The procedure was uneventful, and the symptoms resolved completely after the procedure. Targeted epidural steroid injection might be a useful and safe diagnostic and therapeutic approach in patients affected by cervical radiculopathy due to a VA loop. To our knowledge, this is the first case of a VA loop associated with cervical radiculopathy treated with this technique.

Is the Vertebral Posterior Line a Safety Landmark for Cervical Posterior Screw Insertion? - Radiological Study of the Vertebral Artery in the Cervical Spine

At posterior cervical fixation, iatrogenic injury of the vertebral artery (VA) must be avoided. As the VA is usually located in front of the posterior line of the vertebral body, intraoperative lateral fluoroscopy is used to identify the line. We investigated in how many of 105 patients (210 VAs) this line is a safe marker. We also inspected the original cervical magnetic resonance angiograms (MRA) of 105 consecutive patients who had been treated for other than cervical spine diseases to study some anatomical characteristics of the VA in the cervical spine. The distance from the posterior line of the vertebral body to the posterior VA surface was classified as safe, as requiring attention, and as unsafe. Among the 210 VAs, four hypoplastic vessels were excluded from this study; consequently, 206 VAs were available for assessment. The average distance exceeded 6 mm, it was shorter at the upper cervical level. Although in at least 200 VAs (97.1%) the distance between C4 and C7 was safe, in only 170 VAs (82.5%) was it safe at C3. We observed a total of 31 tortuous loops in 17 VAs; their presence had a significant negative effect on the usefulness of the safety line. Although the posterior line of the vertebral body may be useful for safe screw insertion at the C4-C7 level, it may be less useful at C3. In the presence of tortuous VA loops, close attention must be paid to the reliability of the safety line during cervical spine surgery.

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.

Microsurgical Strategies for the Treatment of Compression Neuropathies Secondary to Vertebrobasilar Dolichoectasia: From Simple Decompression to Sling Transposition

BACKGROUND

Vertebrobasilar artery dolichoectasia may result in neural element compression anywhere along its course within the cervical region, the craniocervical junction or in the posterior fossa. The clinical syndromes most often observed include cranial neuropathy, bulbar dysfunction, myelopathy and cervical radiculopathy. When indicated, the operative techniques utilized to address vertebrobasilar artery dolichoectasia must be individually tailored, can be technically challenging, and have been rarely expounded.

OBJECTIVE

To share selected cases that demonstrate the variety of pathological states caused by vertebrobasilar artery dolichoectasia as well as our experience in managing this condition.

METHODS

Here we review examples of pathological impingement of neural elements compressed by ectasia within the vertebrobasilar arterial system throughout its anatomic course. The surgical techniques we have employed to alleviate the compression, including simple decompression as well as sling-assisted arterial transposition, are described. The evolution and refinement of our transposition technique are detailed.

RESULTS

A wide range of pathological conditions may result from compression of neural structures throughout the course of the vertebrobasilar system. Compression of cervical nerve roots, the spinal cord, brainstem, and cranial nerves can be seen. Microsurgical management may be indicated in selected cases with gratifying results.

CONCLUSION

Pathological compression of neural structures throughout the course of the vertebrobasilar system should be recognized. When indicated, microsurgical decompression must be tailored to the individual symptomology and the unique anatomic relationship in each case with the potential to prevent neurological worsening and, in many cases, improve functional outcome.

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.