With a prevalence of 10 to 15% in adults, tinnitus is a common complaint that can significantly impair quality of life. Frustratingly, there is often no traceable cause, and instead clinical approaches tend to be dedicated to helping patients cope with their condition. However, radiologists should adopt a practical diagnostic approach to identify treatable underlying diseases.
Speaking at today’s session, ‘My three most dreaded head and neck requests’, Dr. Berit Verbist, a neuro, head and neck radiologist at Leiden University Medical Center in the Netherlands, will discuss when and how to image patients with tinnitus, and addressing new insights in the diagnostic approach thanks to technical developments in CT.
Before any imaging is performed, detailed knowledge of the clinical history, the characteristics of tinnitus, audiological measures and clinical examination – including otoscopic findings – are essential to identify the patients for whom imaging is indicated and to determine the optimal diagnostic imaging strategy: MR, MR angiography (MRA), dynamic MRA, CT, CT angiography (CTA), dynamic CTA, and digital subtraction angiography (DSA).
Underlying non-pulsatile tinnitus may result from conditions such as blockage of the external ear canal, ear infections, and hearing loss due to Ménière’s disease, neuromas, and presbyacusis, she explained. In these cases, imaging is reserved for patients with unilateral tinnitus and/or asymmetric hearing loss to rule out vestibular schwannoma or for patients with somatosensory tinnitus to look for cervical spine pathology. Treatment is usually symptomatic.
Meanwhile, in pulsatile tinnitus there is a high chance of identifying underlying treatable causes: vascular pathologies such as malformations, aneurysms, and stenoses; neoplasms like paraganglioma; osseous pathology such as otosclerosis; and neurological diseases, including intracranial hypertension or systemic disorders such as anaemia.
In particular for vascular pathologies, the role of the radiologist includes not only the pretherapeutic assessment but also the therapy, since endovascular embolisation is the first-line treatment for dural arteriovenous fistulas (dAVFs) and a valuable treatment option in arteriovenous malformations (AVMs), Verbist noted.
In recent years, radiologists have investigated the role of dynamic CTA (4D-CTA) in detection and classification of dAVFs.
Whereas conventional CTA provides information of vascular anatomy at a single time point during the passage of a contrast bolus, 4D CTA enables non-invasive evaluation of flow dynamics by multiple subsequent acquisitions or a continuous volume CT acquisition. As such, 4D CTA combines the information of CTA and DSA, and has the potential to replace the invasive, more costly and time-consuming DSA as well as reducing radiation exposure.
“4D CTA can identify vascular malformations that may present with tinnitus, like dAVFs or AVMs. It is also useful for evaluation of the precise angioarchitecture, and thus for risk assessment of haemorrhage and treatment planning,” Verbist told ECR Today. “Previously, DSA was needed to diagnose or rule out dAVF. However, DSA is an interventional procedure that carries a risk of neurologic complications such as emboli.”
Identification of an underlying cause of tinnitus is important for treatment decisions and prognosis estimation, and any delay will prolong the patient’s suffering and may lead to endless referral trajectories and increased health care costs.
“The challenging part is to choose the imaging modality that will most likely reveal an underlying lesion, such as CT for otosclerosis or MRI for idiopathic intracranial hypertension and to decide if additional imaging studies are needed to be considered in case the examination is negative. Thorough clinical assessment of the patient and good communication with referring doctors is essential for taking these decisions,” she continued.
Update on hoarseness
Also at today’s session, Dr. Edith Vassallo, resident radiologist specialising in head and neck at Mater Dei Hospital in Msida in Malta, will present the latest thinking on imaging associated with hoarseness.
Dysphonia affects a third of people at some point in their lifetime, while an estimated one in 13 adults experiences it annually, according to the literature. This relatively common condition has a broad spectrum of potential causes making accurate diagnosis challenging, she told ECR Today.
B: Axial T2-weighted sequence at the same level demonstrates a hyperintense well-circumscribed mass with hypointense linear foci within it. This was confirmed to be a laryngeal carcinoma at histology. These imaging findings highlight the characteristic signal intensity of this lesion on both CT and MRI that helps significantly narrow the differential diagnosis (provided by Dr. Edith Vassallo).
Radiologists therefore need to know the underlying pathologies that may result in hoarseness, and they must have an in-depth knowledge of the associated anatomy for diagnosis and differential diagnoses and of adequately tailored protocols for correct interpretation. For example, slice thickness is pivotal, and small submucosal lesions will be missed unless thin slices are used. Furthermore, proper reconstruction is needed for an accurate diagnosis; images must be reconstructed along the plane of the vocal cords to avoid false image interpretation, according to Vassallo.
She pointed to how studies showed that ultrafast MRI using a dedicated coil design can detect motility disorders of the vocal cords, precluding the need for endoscopy. However, further studies are needed to determine whether this protocol can in the future replace conventional endoscopy in selected cases. Cine-MRI for assessing mobility of vocal folds is also showing promise, she noted.
CT and MRI both have pros and cons for imaging cancers associated with hoarseness. Certain MRI signal characteristics in T2-weighted imaging may be diagnostic, and MRI may be more accurate than CT in T staging. MRI is also best for assessment of tumours in the brain causing hoarseness. Meanwhile, CT allows for the assessment of the thorax for advanced cancer cases to look for lung metastases or in patients with normal head and neck findings and suspected pathology in the mediastinum.
“Radiologists must keep in mind that pathology causing hoarseness can be localised anywhere from the brainstem, all the way down to the mediastinum. They must therefore be familiar with both the anatomy as well as the long list of differentials for selection of the appropriate imaging tools,” Vassallo said.
LIVE
Special Focus Session, Thursday, September 24, 17:00–18:00
SF 2b My three most dreaded head and neck requests
- Chairperson’s introduction
Piotr Golofit; Szczecin/PL - Tinnitus
Berit Verbist; Leiden/NL - Enlarged lymph nodes
Roberto Maroldi; Brescia/IT - Hoarseness
Edith Vassallo; Msida/MT - Live Q&A: How to deal with symptomatic patients without definite imaging findings?
FURTHER READING
Laureano MR, Onishi ET, Bressan RA (2016) The effectiveness of acupuncture as a treatment for tinnitus: a randomized controlled trial using (99m)Tc-ECD SPECT. Eur Radiol. 26(9):3234-42: european-radiology.org/4164
Han F, Xu M, Xie T et al (2018) Efficacy of ultrasound-guided core needle biopsy in cervical lymphadenopathy: A retrospective study of 6,695 cases. Eur Radiol. 28(5):1809-1817: european-radiology.org/5116
Purohit BS, Hermans R, Op de Beeck K (2014) Imaging in pulsatile tinnitus: Diagnostic pearls and potential pitfalls. ECR 2014 / C-1114: myESR.org/141114
Limeme M, Bouabidi S, Khaireddine N et al (2015) Unilateral Vocal Cord Paralysis: A Review of CT Findings. ECR 2015 / C-0937: myESR.org/15937
Montoya S, Portanova A, Bhatt AA (2019) A radiologic review of hoarse voice from anatomic and neurologic perspectives. Insights Imaging. 10(1):108: i3-journal.org/786