The usefulness of Valsalva computed tomography as an assessment tool for the Eustachian tube

CT and MRI in the Preoperative Planning of Balloon Dilation of the Eustachian Tube: Literature Review

Balloon dilatation of the Eustachian tube (BET) is a surgical treatment method for Eustachian tube dysfunction (ETD), which relieves the symptoms in the majority of cases. However, there are potential intraoperative risks associated with BET; the decision-making process with regard to indications for BET is not standardized up to date. The objective of this study was to review the role of computed tomography (CT) and magnetic resonance imaging (MRI) in the preoperative planning of BET. The literature review is based on a database search performed in August 2022. BET is classified into transtympanic and nasopharyngeal. CT of the temporal bone provides good visualization of the site of obstruction, which allows to choose the adequate approach. Transtympanic approach is associated with risks of internal carotid artery damage due to possible carotid canal anomalies. This risk can be prevented with preoperative CT scan of the temporal bone. In case of nasopharyngeal BET, there is no sufficient data considering risks of possible artery damage, although CT can provide accurate measurements of ET. MRI is useful for differential diagnosis of conditions imitating ETD, such as endolymphatic hydrops and nasopharyngeal carcinoma. Thus, it is feasible to perform CT and MRI before BET to personalize the management of ETD patients.

Assessment of the Eustachian tube: a review

BACKGROUND

Dysfunction of the Eustachian tube (ET) can lead to negative pressure within the middle ear, which, in turn, causes various pathological changes. Multiple testing methods for ET function have been devised, each with its own advantages and disadvantages. Knowing the characteristics of each ET function test and the unique characteristics of ET dysfunction (ETD) in children are prerequisites for choosing the optimal assessment method. For a comprehensive diagnosis, assessment should also include the localisation of any sites of obstruction. This review aims to summarise the methods of evaluating ET function and locating sites of ET lesions.

METHODS

Articles evaluating ET function, localising lesions in the ET, and ETD in children were collected from the PubMed database. We selected only relevant English publications.

RESULTS

ETD in children has different characteristics to those in adults. The appropriate tests for assessing ET function depend on the specific conditions of the individual patient. Valsalva computed tomography can provide information on the soft and bony anatomy of the ET to facilitate identification of lesion sites.

CONCLUSION

An accurate diagnosis should be based on a combined analysis of objective and subjective results, with interpretation made in conjunction with clinical history and physical examination. A comprehensive assessment should include lesion localisation. When assessing ETD in children, it is important to take into account the characteristics of this population.

The role of Eustachian tubography and Valsalva CT in Eustachian tube balloon dilation

BACKGROUND

Not many imaging techniques have been reported in Eustachian tube imaging.

PURPOSE

To investigate the role of selective Eustachian tubography (SET) and Valsalva computed tomography (CT) in patients who underwent Eustachian tube balloon dilation (ETBD).

MATERIAL AND METHODS

Eligible patients were aged 18 years and older with chronic Eustachian tube dysfunction who had failed medical treatment. On the day of the procedure, Valsalva CT and SET were performed. Participants underwent fluoroscopic ETBD with a 6×20-mm balloon catheter. Clinical examinations to check for the ability to perform the Valsalva maneuver and ETDQ-7 score change were conducted at one week and then at one, two, and six months. Follow-up Valsalva CT was performed in the one-month follow-up.

RESULTS

A total of 30 ears in 23 patients (16 right ears, 14 left ears; 10 women, 13 men) underwent ETBD from August 2018 to November 2019. Positive CT patency was higher in follow-up Valsalva CT than baseline Valsalva CT (40% and 23.3%, respectively) (P = 0.006). In SET, positive patency was observed in 13 of 25 ears. Response to balloon dilation was observed in 18 of 25 patients. Clinical success was achieved in 16 of 27 ears. Response to balloon dilation was the only significant predictor of clinical success (P = 0.012).

CONCLUSION

SET depicted the lumen of the Eustachian tube; thereby, it could be a potentially valuable tool in ETBD. Valsalva CT provides additional information about the cartilaginous portion of the Eustachian tube.

Cartilage tympanoplasty in the treatment of adhesive otitis media with and without Eustachian tube balloon dilatation

Purpose

To compare cartilage tympanoplasty (CT) combined with eustachian tube balloon dilatation (ETBD) and cartilage tympanoplasty alone as a surgical treatment modality for adhesive otitis media (AdOM) in terms of graft healing, audiological outcomes, and impact on life style, using Chronic Otitis Media Outcome Test 15 (COMOT-15).

Methods

50 patients with AdOM were randomly classified into 2 groups: 25 patients for cartilage tympanoplasty only (CT group) and 25 patients for cartilage tympanoplasty combined with eustachian tube balloon dilatation (CT + ETBD group). Clinical outcomes in both groups were compared at 3 and 6 months of follow up.

Results

There was no significant difference in graft healing between the two groups. Postoperative COMOT-15 scores significantly decreased in both groups with a significant difference between the groups with regard to the decrease in COMOT-15 scores at 3 and 6 months of follow-up (P < 0.05). Hearing improvement was achieved, as the mean preoperative ABG was 26.5 ± 5.4 and 27.1 ± 4.6 dB, and the mean postoperative ABG at 6 months was 19.4 ± 4.4 and 14.6 ± 3.9 dB in the CT and the CT + ETBD groups, respectively. The difference in the magnitude of ABG reduction in the two groups was significant at 3 and 6 months of postoperative follow-up (P < 0.05) in favour of the CT + ETBD group.

Conclusion

ETBD can increase the success rate of cartilage tympanoplasty in patients with AdOM by enhancing the audiological outcome and quality of life.