Vertebral artery injuries

A preliminary study on colour Doppler ultrasound for the evaluation of intervertebral stenosis of the vertebral artery

AIM

To determine the optimal thresholds for assessing intervertebral segment stenosis through haemodynamic parameters of colour Doppler ultrasound compared with computed tomography (CT) angiography.

MATERIALS AND METHODS

Fifty-four patients diagnosed with intervertebral stenosis on colour Doppler imaging were included. Twenty patients with normal vertebral arteries constituted a control group. Peak systolic velocity at the intervertebral stenosis (PSV_IV-S) and the intervertebral segment distal to the stenosis (PSV_IV-D), end diastolic velocity at the intervertebral stenosis (EDV_IV-S), and the intervertebral segment distal to the stenosis (EDV_IV-D) were measured, and the ratios of PSV_IV-S/PSV_IV-D and EDV_IV-S/EDV_IV-D were calculated. Cut-off values for the diagnosis of <50%, 50-69%, and 70-99% stenosis were determined using a receiver operating characteristics curve.

RESULTS

The optimal cut-off values of haemodynamic parameters for evaluating the intervertebral artery for <50% stenosis were PSV_IV-S ≥81.5 cm/s, EDV_IV-S ≥24.5 cm/s, PSV_IV-S/PSV_IV-D ≥1.49, and EDV_IV-S/EDV_IV-D ≥1.28; for 50-69% stenosis were PSV_IV-S ≥137.5 cm/s, EDV_IV-S ≥36.5 cm/s, PSV_IV-S/PSV_IV-D ≥3.14, and EDV_IV-S/EDV_IV-D ≥2.75; and for 70-99% stenosis were PSV_IV-S ≥216 cm/s, EDV_IV-S ≥55 cm/s, PSV_IV-S/PSV_IV-D ≥4.31, and EDV_IV-S/EDV_IV-D ≥4.16. PSV_IV-S/PSV_IV-D was the most superior haemodynamic parameter, with areas under the curve of 1.000, 0.906, and 0.968 for the diagnosis of <50%, 50-69%, and 70-99% stenosis, respectively.

CONCLUSION

Colour Doppler sonography reliably identifies intervertebral stenosis. The results can be used as a preliminary reference for evaluating intervertebral stenosis.

Management Approach of Penetrating Vertebral Artery Injury with Concomitant Cervical Nerve Root Injury in Regional Hospital: Report of Two Cases

Penetrating vertebral artery injury is uncommon yet potentially fatal. We present two cases of penetrating vertebral artery injury with concomitant cervical nerve root injury managed in our centre. The first case was a young gentleman who suffered from neck injury by broken metal fragment. Cervical nerve root injury was suspected preoperatively. Massive bleeding from vertebral artery was encountered during wound exploration. It was managed by ligation, followed by retrograde endovascular embolisation. The second case was a young lady being assaulted with knife and fork over the neck. She was also suspected to have cervical nerve root injury preoperatively. Vascular control of vertebral artery was achieved with endovascular intervention. Subsequent operation for foreign body removal and nerve root repair was performed with minimal bleeding intraoperatively. Management approach of penetrating vertebral artery injury with concomitant cervical nerve root injury and the role of endovascular intervention were discussed.

Lethal penetrating stab injury to the vertebral artery: A case report with review of literature

The vertebral arteries are rarely injured in penetrating neck trauma due to their deep location in the foramen transversarium. These injuries in isolation are not associated with neurological deficits or ischemic changes on radiology as the collaterals are usually sufficient. We report a case of fatal unilateral vertebral artery stab injury leading to bilateral cerebellar and brainstem infarction. The carotid Doppler ruled out the presence of any carotid artery injury. Life-threatening injuries are possible in the presence of hypoplastic contralateral vertebral artery or inadequate flow from the anterior circulation not making up for the deficit. This emphasizes that thorough evaluation and timely management of suspected injuries to even a single vertebral artery should be undertaken.

Recurrent dislocations of the atlantooccipital and atlantoaxial joints in a halo vest fixator are resolved by backrest elevation in an elevation angle-dependent manner

BACKGROUND CONTEXT

Halo fixation is now universally performed in the initial reduction and fixation of unstable upper cervical spine injuries; however, persistent high instability and recurrent dislocations of the atlantooccipital and atlantoaxial joints after fixation are not well recognized.

PURPOSE

The aim was to describe persistent instability of traumatic dislocations of the atlantooccipital and atlantoaxial joints after halo fixation and a useful method for preventing instability.

STUDY DESIGN

This was a case report of a patient who survived traumatic dislocations of the atlantooccipital and atlantoaxial joints.

PATIENT SAMPLE

A 73-year-old woman diagnosed with dislocations of the atlantooccipital and atlantoaxial joints along with multiple other injuries sustained in a traffic accident was included.

METHODS

After initial closed reduction and halo fixation, congruity of the atlantooccipital and atlantoaxial joints was evaluated using, condylar gap, atlantodental interval, and flexion angulation of C1-C2 after the initial examination and before surgery.

RESULTS

Changes in parameters 12 hours after halo fixation revealed re-dislocations and instability of the joints. Backrest elevation with halo fixation tended to reduce re-dislocations. Therefore, we carefully increased the backrest angle and measured the parameters at several angles of elevation within a range that did not affect vital signs to observe the effectiveness of elevation against re-dislocations. Elevation changed the parameters in an elevation angle-dependent manner, and these changes suggested that elevation was effective for reducing re-dislocation of both the atlantooccipital and atlantoaxial joints during halo fixation. With no major complications, this method enabled us to maintain good congruity of the joints for approximately 2 weeks until posterior spinal fusion with internal fixation.

CONCLUSIONS

Backrest elevation with halo fixation appears safe to be performed without any other devices and is beneficial for blocking re-dislocation of both the atlantooccipital and atlantoaxial joints as well as possible secondary damage to the upper cervical spinal cord during the external fixation period.

Vertebral artery dissect injury with brown-séquard syndrome by a neural foramen penetrated electric screw driver bit : a case report

There are few reports in the literature of complete obstruction of the vertebral artery (VA) due to an electric screw driver bit penetration through the neural foramen into the spinal canal with Brown-Séquard syndrome (BSS). A 25-year-old man was admitted to the emergency department with a penetrated neck injury by an electric screw driver bit after a struggle. The patient presented the clinical features of BSS. Computed tomography scan revealed that the electric screw driver bit penetrated through the right neural foramen at the level of C3-4, and it caused an injury to the right half of the spinal cord. Emergent angiography revealed VA dissection, which was managed by immediate coil embolization at both proximal and distal ends of the injury site. After occlusion of the VA, the electric screw driver bit was extracted under general anesthesia. Bleeding was minimal and controlled without difficulties. No postoperative complications, such as wound dehiscence, CSF leakage, or infection, were noted. Endovascular approaches for occlusion of vertebral artery lesions are safe and effective methods of treatment.

Contemporary management of combat-related vertebral artery injuries

BACKGROUND

Vertebral artery injuries (VAIs) following cervical trauma are uncommon. Advances in imaging technology and emerging endovascular therapies have allowed for the improved diagnosis and treatment of VAIs. We aimed to examine the contemporary management of combat-related penetrating VAIs during current US military operations.

METHODS

A retrospective review was performed on US casualties with combat-related VAIs evacuated to a single military institution in the US from September 2001 to 2010 for definitive management. Casualty demographics, mechanism of injury, location and type of VAI, neurologic sequela, associated injuries, method of diagnosis, and therapeutic management were collected.

RESULTS

Eleven casualties with a mean age of 26 years (mean [SD] ISS, 18 [7.0]) were found to have VAIs from gunshot wounds (6, 55%) or blast fragments (5, 45%). Cervical spine fractures (8, 72%), facial fractures (5, 45%), and spinal cord injury (3, 27%) were not uncommon. One casualty experienced a posterior cerebellar and parietal infarcts. All injuries were evaluated with digital subtraction angiography, 64-slice multidetector row computed tomography, or both. Casualties were noted to have vertebral artery occlusion (4, 36%), pseudoaneurysms (5, 45%), dissection (1, 9%), or arteriovenous fistula (1, 9%), with most injuries occurring in the V2 segment (6, 55%). Pseudoaneurysms were treated with coiling or stent-assisted coiling. Of 11 casualties, 6 were managed nonoperatively, half of whom with anticoagulation or antiplatelet therapy.

CONCLUSION

VAIs are infrequent in modern combat operations, occurring in only 3% of casualties experiencing arterial injuries and are often incidentally discovered during the delayed secondary evaluation of penetrating face and neck injuries at higher echelons of care. One should have a high index of suspicious for a VAI in a casualty with concurrent cervical spine fractures. Endovascular therapies using coils and covered stents have expanded the management options and simplified the treatment of combat-related VAIs.

LEVEL OF EVIDENCE

Therapeutic study, level V.

Subclavian steal syndrome like appearance resulting from a vertebral artery origin stenosis: a case report

Partial steal has been regarded as a classic ultrasound appearance of subclavian steal syndrome. We report a case with the vertebral artery origin stenosis and intact subclavian artery, which showed the similar partial steal ultrasound features. The following computerized tomography angiography confirmed the stenosis. Therefore, when an alternating flow in the vertebral artery is detected, the investigation of its origin must be performed besides the ipsilateral subclavian artery.

Isolated contralateral vertebral artery injury in a stab wound to the neck

Ipsilateral vertebral artery injuries are a rare entity following trauma to the neck. We discuss the first case of an isolated right vertebral artery injury in a patient with a left stab wound. The patient required bilateral neck explorations and, due to massive bleeding, a median sternotomy in order to obtain control of the proximal segment of the right vertebral artery. We emphasize the importance for trauma surgeons to be familiar with basic but important vascular exposures. The anatomy, surgical exposure, and management of these rare injuries are discussed.

Ultrasound of the extracranial vertebral artery

Ultrasound of the extracranial vertebral artery (VA) is a valuable technique. This review outlines VA anatomy and the technical aspects of ultrasound scanning of the VA, then proceeds to demonstrate and discuss the use of ultrasound of the VA in identifying vertebral-subclavian and coronary-subclavian steal syndromes, aortic valve disease, stenosis or occlusion of the VA itself, dissection and aneurysm of the VA, and vertebrobasilar insufficiency.

Interventional radiology

PURPOSE OF REVIEW

The capabilities of interventional radiology are developing faster than perhaps any other branch of medicine. Coupled with and fuelled by parallel advances in computer technology, medical physics and developments in endovascular catheter technology, interventional radiologists are innovating not only replacements for open surgeries, but entirely new therapies as well. This has, however, provided a range of new potential complications for the patient and, in contrast to other areas, presents risks for the anesthesiologist as well.

RECENT FINDINGS

The techniques involved in interventional radiology have found applications throughout not only medicine but surgery in particular. Here there has been a medicalization of surgical procedures. CT scanning has evolved to the extent that it is now possible to utilize multislice CT scanners, ones with multiple, flat panel digital detectors, to provide real time CT fluoroscopy. Similarly this technology has facilitated the construction of hybrid iMR/X-ray systems, thus enabling dual modality imaging without moving the patient. Another facet of the new breed of iMR systems is their integration in real time with computerized, frameless stereotactic navigation systems. This has enabled the radiological image to keep pace with the changes in anatomy consequent to anesthetic and surgical manipulations.

SUMMARY

In the light of these new developments in interventional radiology there is much research to be done. Further developments in imaging and computer processing technology will doubtless make possible the real time integration of anatomical image with metabolic state and functional anatomy. The impact of the hazards of these new techniques on the safety of anesthesia has, however, been the subject of virtually no research. A particularly needy area will be the ergonomics of the delivery of anesthesia care in these new environments.