Standard Diffusion-Weighted Imaging in the Brain Can Detect Cervical Internal Carotid Artery Dissections

A misdiagnosed aneurysm of the petrous internal carotid artery: A case report

INTRODUCTION

An aneurysm is characterized by the weakening of the arterial wall, which leads to a bulge that can be filled with blood. Aneurysms of the petrous portion of the internal carotid artery are rare and predominantly detected incidentally. This is a report of multiple misdiagnoses of an aneurysm of the petrous segment of the internal carotid artery (ICA) that highlights its imaging-based diagnosis and risk of mortality.

PRESENTATION OF CASE

A 60-year-old woman with chronic kidney disease and a history of stroke presented with left ear discharge, decreased hearing, and non-pulsatile tinnitus that had persisted for four months. Clinical examination showed wet tympanic membrane perforation, and imaging revealed an ill-defined infiltrative mass involving the left petrous apex initially misdiagnosed as glomus jugulare. Diagnostic computed tomography (CT) angiography revealed a left aneurysm in the petrous part of the ICA, which was successfully treated with interventional radiology. Follow-up was planned for infectious diseases and internal medicine, but she was lost to follow-up by the otolaryngology department.

DISCUSSION

Aneurysms in the petrous portion of the ICA are rare and usually asymptomatic. However, their clinical manifestations vary, and they have various differential diagnoses. CT and magnetic resonance imaging are essential for diagnosis, and CT angiography is the gold standard.

CONCLUSION

Diagnosing petrous ICA aneurysms requires a high level of suspicion and CT angiography. Their clinical presentations vary from asymptomatic to severe. Case-specific management and endovascular treatment yield positive neurological outcomes.

Uncommon Bilateral Carotid Artery Dissection in a Farmer: The Perils of Heavy Weight Lifting

Bilateral internal carotid artery (ICA) dissection on heavy weight lifting is a very rare cause of stroke in young patients. Arterial dissection is due to a tear in the intima and internal elastic lamina which leads to extravasation of blood into the media and subintimal plane. Clinical diagnosis of carotid artery dissection is difficult with common clinical presentations like headache and neck pain. Here we present a case of a 40-year-old young man who presented to us (tertiary referral center) with headache and quadriparesis. MRI brain showed multiple acute infarcts in bilateral centrum semiovale extending up to frontal periventricular white matter with few tiny foci in bilateral medial temporal and left gangliocapsular regions and CT cerebral angiography showed bilateral ICA dissection. He was treated with low molecular weight heparin and was discharged for follow-up with regular physiotherapy.

Diagnostic potential of routine brain MRI and high-resolution, multi-contrast vessel wall imaging in the detection of internal carotid artery dissection

Objective

Cervical artery dissection (CAD) is one of the major causes of stroke and most commonly occurs at the site of the extracranial internal carotid artery (ICA). This study aimed to assess the value of routine brain MRI, clinical information, and high-resolution, multi-contrast vessel wall MR imaging (hrVWI) for the timely detection of ICA dissection.

Methods

A total of 105 patients with CAD and 105 without CAD were recruited for this study. The lesion type in the patients was determined based on images from different modalities, including brain MRI, magnetic resonance angiography (MRA), computed tomography angiography (CTA), digital subtraction angiography (DSA), ultrasonography, and hrVWI and clinical information. Each lesion was reviewed to determine the type following a stepwise procedure by referring to (1) brain MRI only; (2) brain MRI and clinical information; (3) hrVWI only; and (4) hrVWI, CTA, DSA, and clinical information.

Results

Typical clinical presentations of patients with potential CAD include headache, neck pain, and/or Horner's syndrome. Representative imaging signs in the brain MRI included a crescentic or circular iso- or hyperintensity around the lumen, a curvilinear and isointense line crossing the lumen, or aneurysmal vessel dilation. Based on brain MRI alone, 54.3% (57/105) of the patients with CAD were correctly classified, and the accuracy increased to 73.3% (77/105) when clinical information was combined (P < 0.001) with high specificity and low sensitivity. Further analysis showed that hrVWI had the superior capability in detecting CAD, with a sensitivity and a specificity of 95.1% and 97.0%, respectively.

Conclusion

The combination of brain MRI and clinical information could be used for the diagnosis of CAD; however, hrVWI should be sought for uncertain cases.

Vascular Injuries in Head and Neck Trauma

Blunt and penetrating vascular injuries of the head and neck can represent life-threatening emergencies that require accurate detection to prevent devastating and long-lasting consequences. Implementing appropriate screening criteria to indicate imaging studies is crucial as there is a variable latent time before the onset of clinical manifestations. Computed tomography angiography, MR imaging, and digital subtraction angiography represent the imaging modalities of choice to evaluate vascular injuries. The aim of this review is to provide a description of the different types of vascular injuries, describe the importance of each imaging modality, and recognize the imaging appearance of traumatic vessel injury.

Emergent neurovascular imaging in patients with blunt traumatic injuries

Blunt cerebrovascular injuries (BCVIs) are commonly encountered after blunt trauma. Given the increased risk of stroke incurred after BCVI, it is crucial that they are promptly identified, characterized, and treated appropriately. Current screening practices generally consist of computed tomography angiography (CTA), with escalation to digital subtraction angiography for higher-grade injuries. Although it is quick, cost-effective, and readily available, CTA suffers from poor sensitivity and positive predictive value. A review of the current literature was conducted to examine the current state of emergent imaging for BCVI. After excluding reviews, irrelevant articles, and articles exclusively available in non-English languages, 36 articles were reviewed and included in the analysis. In general, as CTA technology has advanced, so too has detection of BCVI. Magnetic resonance imaging (MRI) with sequences such as vessel wall imaging, double-inversion recovery with black blood imaging, and magnetization prepared rapid acquisition echo have notably improved the utility for MRI in characterizing BCVIs. Finally, transcranial Doppler with emboli detection has proven to be associated with strokes in anterior circulation injuries, further allowing for the identification of high-risk lesions. Overall, imaging for BCVI has benefited from a tremendous amount of innovation, resulting in better detection and characterization of this pathology.

Hypoglossal nerve palsy due to internal carotid artery dissection with pseudoaneurysm formation: An unusual presentation

Internal carotid artery (ICA) dissection is a dangerous condition that results from disruption of the intimal part of the wall of the internal carotid artery. It is a rare disease that may occur spontaneously or as a result of a trauma. Spontaneous dissections of the carotid artery are rare but important causes of ischemic stroke because they usually affect young and middle-aged patients. Up to date, only a few cases were described in the literature about ICA dissection causing isolated cranial nerve palsies, with the Hypoglossal nerve being the most affected. Here, we report a case of a 56-year-old man presenting with progressive dysarthria, dysphagia to liquid diet, and difficult mastication. He was diagnosed as a case of cervical internal carotid dissection with pseudoaneurysm formation causing mass effect resulting in a compressive ipsilateral Hypoglossal nerve palsy based on magnetic resonance imaging (MRI) findings. Angiography confirmed the presence of dissecting pseudoaneurysm which was eventually managed by stenting. This case was reported to highlight and emphasize the importance of radiology, whether diagnostic or interventional, in managing rare and challenging cases such as ICA dissection.