Virtual laryngoscopy—preliminary experience
Introduction
Computed tomographic virtual endoscopy is a non-invasive radiological technique that allows visualisation of intra-luminal surfaces by three-dimensional (3D) reconstruction of air/soft tissue interfaces, in a manner which simulates endoscopy. It can be useful when a patient cannot tolerate clinical examination, or when infection, neoplasm or congenital defects compromise the lumen. The laryngeal area can be assessed from below as well as above [1].
We performed this study to evaluate the clinical utility, advantages and disadvantages of virtual laryngoscopy and to describe our initial experiences with this technique.
Section snippets
Material and methods
Patients referred from the otolaryngology clinic for CT of the larynx had virtual laryngoscopic reconstructions performed from the images obtained. All had been questioned and examined in the outpatient department and initially underwent other diagnostic investigations including conventional endoscopy of the larynx. Axial scans were obtained on a helical CT scanner (Toshiba Xpress/GX, Toshiba Corporation, Tokyo, Japan). Patients lay supine, breathing quietly and were asked not to swallow for
Results
Twelve patients were included in the study. There were eight men and four women whose ages ranged from 25 to 78 years (mean 49 years). Two scans were normal (Fig. 1a and b). Three patients had vocal cord nodules (Fig. 2a and b) and two had vocal cord cysts (Fig. 3a–c). There were two cases of Reinke's oedema (Fig. 4a–c), one of leucoplakia, one vocal cord neoplasm and one patient had stenosis due to prior radiotherapy (Fig. 5a–c).
Discussion
Conventional endoscopy allows direct visualisation of mucosa and can be used for biopsy. It is however, invasive and requires sedation, and endoscopic assessment depends on the operator's experience [2]. More importantly, it may not be possible to progress beyond a stenosis or obstruction, thus hampering complete assessment of the lesion. In addition, viewing is limited to the lumen, restricting transmural evaluation. In contrast, virtual laryngoscopy is non-invasive and uses two-dimensional
References (8)
- et al.
Head and neck computed tomography virtual endoscopy: evaluation of a new imaging technique
Laryngoscope
(1999) - et al.
Virtual laryngotracheal endoscopy based on geometric surface modelling using spiral computed tomography data
Ann Otol Rhinol Laryngol
(2002) - et al.
Virtual laryngoscopy
Ann Otol Rhinol Laryngol
(1999) - et al.
Interactive virtual endoscopy
AJR
(1997)
Cited by (18)
Anesthesia and Airway Management for Oral Cancer and Microvascular Surgery
2017, Maxillofacial Surgery, 3rd Edition: Volume 1-2Virtual endoscopy - A new assessment tool in difficult airway management
2015, Journal of Clinical AnesthesiaCitation Excerpt :Like conventional endoscopy, CT VE has been used for surgical planning, disease monitoring, or patient education [27]; we now use this technology as an additional tool in planning an airway strategy for patients with preexisting airway-related pathology. Virtual endoscopy has been used to evaluate pathology at various sites along the airway, from nasopharynx to larynx to the tracheobronchial tree [28–32]. Here, we have demonstrated that glottic, subglottic, and multilevel lesions can all be accurately reproduced to provide us with a realistic image of the airway and aid us in airway management planning.
Virtual laryngoscopy and combined laryngoscopic-bronchoscopic approach for safe management of obstructive upper airways lesions
2014, British Journal of AnaesthesiaConventional endoscopy versus virtual laryngoscopy in assessment of laryngeal lesions
2013, Egyptian Journal of Radiology and Nuclear MedicineCitation Excerpt :The use and application of the three-dimensional (3D) reconstructions generated from suitable files (DICOM) of CT or MRI have been expanding recently. This allows physicians to observe anatomic cavities and structures with an incredible amount of details and can display even the textures of different tissues (2,10). CTVL is the computer-generated, three dimensional reconstruction of two-dimensional CT images (10).
Utility of 64 multislice CT-virtual laryngoscopy in presurgical planning of laryngeal and hypopharyngeal carcinomas
2012, Egyptian Journal of Radiology and Nuclear MedicineCitation Excerpt :The treatment plan for an individual patient with laryngeal cancer depends on a number of factors, including location of the tumor, stage of the tumor, histology, and the patient's age and other medical co morbidities (2). Computed tomographic virtual endoscopy is a non-invasive diagnostic modality allowing visualization of intra-luminal surfaces by three-dimensional representation of two dimensional reconstruction of air/soft tissue interfaces (3,4). Patients benefit from the virtual laryngoscopy without the intolerance associated with the direct endoscopy, or the presence of luminal obstruction due to an infection, neoplasm or congenital defects (5).