Magnetic Resonance Imaging Helped Detect the Precise Cause of Postintubation Hoarseness Presenting as Vocal Cord Paralysis

Abstract

To the Editor: During preoperative assessment of a 20-yr-old male patient scheduled for closure of an enterocutaneous fistula consequent to previous emergency abdominal surgery, he reported persistent dysphonia (difficult and labored speech) requiring active effort to phonate and was breathless and tired while speaking. Indirect laryngoscopy (IDL) revealed normal looking vocal cords (VC) with the right VC in adduction and absent abduction on phonation. The left VC had normal movement. Because there were no other airway problems, we planned for general anesthesia using a 7.0-mm tracheal tube. Although the patient’s voice improved in the immediate postoperative period it reverted to the preoperative condition within 24 h. A reversible local pathology for causing the unilateral cord paralysis was suspected. Magnetic resonance imaging (MRI) starting from above vocal cords to below the cricoid cartilage revealed a hematoma beneath the right VC extending to and involving the right vocal fold (Figs. 1B and C). The relationship of the arytenoids to the cricoid cartilage on both sides was intact (Fig. 1D). The patient’s voice improved after corrective microlaryngeal surgery for the hematoma.Figure 1.: (A) Axial view of the neck taken in supine position on MRI intact cord level. (B, C) Sub-vocal cord level shows hematoma (white arrow) in the right vocal fold in two sections of 3 mm. Normal relationship of the arytenoids cartilage at the base with cricoid cartilage (D) excludes subluxation of arytenoid a cause for right cord paresis.Our patient developed unilateral vocal fold dysfunction because of local injury from an earlier intubation. The vocal fold dysfunction presented as breathy weak dysphonia because of the glottic incompetence, altering subglottic airflow and uncoordinated vocal fold vibration that leads to dysphonia (1). IDL is reported to detect abnormalities in only 22% of patients with voice symptoms and is, at best, a limited screening tool (2). Laryngeal soft tissue injury that may be often missed by IDL can be diagnosed more precisely with MRI scanning (3); it is noninvasive, can better define soft tissue abnormalities, and offers coronal, sagital, and axial views. We suggest the use of MRI scanning to better visualize local soft tissue pathology in cases of persistent dysphonia. Mukesh Tripathi, MD, MNAMS Saumaya S. Nath, MD, PDCC Vivek Kumar, MD Department of Anesthesiology Sanjay Gandhi Postgraduate Institute of Medical Sciences Lucknow, India [email protected] Rakesh K. Gupta, MD Department of Radiodiagnosis Sanjay Gandhi Postgraduate Institute of Medical Sciences Lucknow, India