Evaluation of virtual laryngo-tracheoscopy in upper airway examination after percutaneous tracheostomy

Introduction

The aim of this study is to evaluate possibilities of the virtual laryngo-tracheoscopy (VLT) technique for diagnosis of different deformations in the laryngo-tracheal region after percutaneous tracheostomy (PCT). PCT is a well-established procedure for the treatment of critically ill patients, who need prolonged mechanical ventilation. Fiberoptic laryngo-tracheoscopy is often required for the follow-up of these patients. This procedure, however, involves discomfort and cannot always be used in critically ill patients.

Materials and method

We examined 26 patients (18 males and eight females) who were recruited from intensive care unit patients after PCT. Examinations were performed between a few days and 12 months following PCT and decannulation on a multidetector CT scanner (General Electric Medical System Lightspeed) using the following parameters: 120 kV, 80 mA, rotation = 0.8 s, pitch = 6, slice thickness = 2.5 mm, overlap = 1.8 mm, acquisition time = 10–12 s. Navigation through the laryngo-tracheal lumen as well as reformatted coronal and sagittal images were performed on a GE AW 4 workstation. The diameters of the larynx and cervical trachea were accurately measured.

Results

The pathological changes were mural granulations, tracheal wall flap, and a polypoid mass in the tracheal wall.

Conclusions

VLT allows the dynamic assessment of the central airway and the diagnosis of mural deformities and stenosis. Being noninvasive and short in time, requiring no patient preparation, VLT is ideal for studying the larynx and trachea in former critically ill patients. This technique may offer an alternative to the fiberoptic laryngo-tracheoscopy examination.