Common carotid artery pseudoaneurysm after neck dissection: colour Doppler ultrasound and multidetector computed tomography findings

A Giant Pseudoaneurysm Mimicking Retropharyngeal Abscess in a Child

Pseudoaneurysms of the cervical internal carotid artery are rare and usually result from trauma, infection, or rarely spontaneously. They harbor potential risk of life-threatening hemorrhage and warrant immediate management. Endovascular treatment in the form of stent placement and coiling is a well established technique for dealing with both intracranial and extracranial pseudoaneurysms. We present a case of a child who presented with fever, neck swelling, dysphagia, and respiratory distress in emergency for which clinical diagnosis of a neck abscess was made. Intubation was not possible because of bulge in the retropharyngeal wall. An elective tracheotomy was planned with imaging of the neck. Imaging and careful planning to avoid incision and drainage in the initial presentation led us to diagnose a pseudoaneurysm and successful management. We present this case to highlight the importance of early recognition and timely meticulous management to avoid serious complications and morbidity in a child.

"To-and-fro" waveform in the diagnosis of arterial pseudoaneurysms

Medical ultrasound imaging with Doppler plays an essential role in the diagnosis of vascular disease. This study intended to review the clinical use of “to-and-fro” waveform at duplex Doppler ultrasonography (DDU) in the diagnosis of pseudoaneurysms in the arterial vessels of upper and lower extremities, abdominal aorta, carotid and vertebral arteries as well as to review our personal experiences of “to-and-fro” waveform at DDU also. After receiving institutional review board approval, an inclusive literature review was carried out in order to review the scientific foundation of “to-and-fro” waveform at DDU and its clinical use in the diagnosis of pseudoaneurysms in various arterial vessels. Articles published in the English language between 2000 and 2013 were evaluated in this review study. Pseudoaneurysms in arterial vessels of the upper and lower extremities, abdominal aorta, carotid and vertebral arteries characterized by an extraluminal pattern of blood flow, which shows variable echogenicity, interval complexity, and “to-and-fro” flow pattern on color Doppler ultrasonography. In these arterial vessels, Duplex ultrasonography can demonstrate the degree of clotting, pseudoaneurysm communication, the blood flow patterns and velocities. Spectral Doppler applied to pseudoaneurysms lumen revealed systolic and diastolic turbulent blood flow with traditional “to-and-fro” waveform in the communicating channel. Accurate diagnosis of pseudoaneurysm by spectral Doppler is based on the documentation of the “to-and-fro” waveform. The size of pseudoaneurysm determines the appropriate treatment approach as surgical or conservative.

A false aneurysm

OBJECTIVE

We report a case of a remaining hemi-thyroid following laryngectomy, which was misinterpreted as a pseudoaneurysm.

METHODS

Case report and comment on this understandable error which is easily avoidable.

RESULTS

A 59-year-old man had undergone salvage laryngectomy for recurrent squamous cell carcinoma of the larynx, which had previously been treated with radiotherapy. Three months after his laryngectomy, he presented with a sore neck and subcutaneous collections. Computed tomography revealed a unilateral mass with high signal contrast uptake anterior to the left common carotid artery, which was thought initially to be a carotid pseudoaneurysm. Further investigation, including ultrasonography and a review by the senior head and neck radiologist, demonstrated that this mass was actually the remnant hemi-thyroid preserved at laryngectomy (which is often misshapen compared with a normal hemi-thyroid). The collections were found to be recurrent tumour, and unnecessary further interventions were avoided.

CONCLUSION

Ultrasonography easily distinguishes between a thyroid remnant and a pseudoaneurysm. Furthermore, the opinion of an experienced head and neck radiologist may be vital when interpreting complex post-surgical head and neck radiology.