CT angiography for diagnosis of carotid near-occlusion: a digital subtraction angiography validation study

INTRODUCTION

Carotid near-occlusion (CNO) is a variant of severe stenosis where there is a distal luminal collapse of the internal carotid artery (ICA) beyond a tight stenosis. This study aimed to validate new visual extracranial diagnostic CT angiography (CTA) criteria, for the diagnosis of CNO. The new criteria include distal ICA diameter smaller than contralateral ICA and distal ICA diameter less than or equal to the ipsilateral external carotid artery (ECA). We also assessed the previously described CTA criteria: stenosis ≤ 1.3 mm, ipsilateral distal ICA ≤ 3.5 mm, ipsilateral distal ICA/contralateral distal ICA ratio ≤ 0.87, ipsilateral distal ICA/ipsilateral ECA ≤ 1.27.

METHODS

Fifty-eight patients with ICA stenosis (including the near-occlusion variant) or occlusion on digital subtraction angiography (DSA) were included. These patients had DSA and CTA studies completed within 30 days of each other. DSA was considered the reference test. Two neuroradiologists blinded to the DSA results assessed the CTA images and evaluated the new and previously published CNO diagnostic criteria.

RESULTS

Twenty-eight CNO were identified with DSA. The "distal ICA diameter less than or equal to the ipsilateral ECA" criterion had 79% sensitivity and 83% specificity with excellent interobserver agreement (kappa = 0.80), while three or more of the previously published criteria reached 82% sensitivity and 90% specificity, with a good interobserver agreement (kappa = 0.64).

CONCLUSIONS

CT angiography may be useful for CNO diagnosis. The new visual diagnostic criteria provide acceptable results of sensitivity and specificity with an excellent interobserver agreement. However, false-negative and positive results persist.

Spinal epidural abscess caused by Streptococcus agalactiae in an immunocompetent patient

BACKGROUND

Streptococcus agalactiae is an uncommon microorganism that causes spinal epidural abscess (SEA) and usually affects individuals with a predisposing condition or potential source of infection.

CASE DESCRIPTION

We present the case of an immunocompetent 53-year-old patient with an unremarkable past medical history who developed progressive low extremity weakness, bowel and bladder dysfunction and genital sensory impairment. A neurological exam on admission revealed flaccid proximal paraparesis, T10 sensory level, atonic anal sphincter and normal myotatic reflexes. Urgent neuroimaging showed a large thoracic epidural spinal abscess. Laminectomy and abscess drainage were immediately performed and systemic antibiotic treatment was initiated. Abscess cultures revealed Streptococcus agalactiae. After an exhaustive workup no predisposing factors or local or systemic source for the infection were found.

CONCLUSIONS

We report a singular case of spinal epidural abscess caused by Streptococcus agalactiae in a healthy patient with no predisposing factors. This case also highlights the importance of an early diagnosis and treatment to obtain a better neurological outcome.

Equine pericardium-covered stenting in post-traumatic pseudoaneurysm of cavernous internal carotid artery

We report a case of traumatic intracranial carotid artery pseudoaneurysm treated with an equine pericardium-covered stent. The patient was admitted to the Emergency Department after sustaining severe polytrauma in a motor vehicle accident. A cavernous carotid pseudoaneurysm was detected after an episode of massive epistaxis that required emergent nasal packing. Treatment with parent vessel sacrifice was ruled out after an unfavourable balloon test occlusion. We opted for an equine pericardium-covered stent as a means to immediately seal the wall defect in the setting of massive bleeding secondary to an unstable lesion. We describe the potential benefits and drawbacks of these prostheses and the technical difficulties encountered in this particular case. To our best knowledge, this is the first published case report on a post-traumatic intracranial internal carotid artery pseudoaneurysm successfully treated with an equine pericardium-covered stent.

Embolization through the thyrocervical trunk: vascular anatomy, variants, and a case series

Background and purpose

The thyrocervical trunk (TCT) is the second ascending branch of the subclavian artery. It is considered a ‘border territory’ between interventional vascular radiology and interventional neuroradiology because it gives rise to branches both cervical and to the upper limbs. We describe the TCT branches anatomy, the most frequent variants, and expose eight endovascular procedures performed through the thyrocervical trunk.

Methods

A retrospective review of all the interventional radiology procedures carried out through the TCT in our tertiary care center from August 2014 to January 2017 is presented.

Results

A total of eight endovascular procedures through the TCT including six preoperative embolizations: three paragangliomas, a cervical vertebral metastasis, a cervical vertebral aneurysmal bone cyst, and a very rare case of nerve root extradural cervical hemangioblastoma, as well as two emergency embolizations: a patient with a cervical traumatic active bleeding hematoma and a recurrent hemoptysis in a single ventricle patient.

Conclusions

A correct knowledge of the vascular anatomy, anatomical variants, and anastomosis (especially with the anterior spinal artery) of the TCT is essential for a safe embolization, both preoperatively and on an emergency basis. In cases of recurrent hemoptysis and severe lower-neck injuries, the TCT should always be reviewed.