A Comparative Study of Fiberoptic Laryngoscopy (FOL) and Indirect Laryngoscopy in the Diagnosis of Patients with Vocal Cord Lesions

: Background : Change of voice is one of the common complaints in ENT practice and hoarseness of voice is the commonest symptom of changed voice quality. Hoarseness is invariably the earliest manifestation of conditions directly or indirectly affecting the voice apparatus. Though most common causes of hoarseness are benign and vocal abuse is the commonest among them, but we should always investigate for more sinister pathology like malignancy. The aim of this study was to compare the diagnostic yields of fibreoptic laryngoscopy (FOL) with that of indirect laryngoscopy in the diagnosis of vocal cord lesions. Objectives: To compare fibreoptic laryngoscopy (FOL) and indirect laryngoscopy in the diagnosis of vocal cord lesions as the cause of voice change. Methods: This is a cross-sectional study which has been conducted in the Department of ENT and Head Neck Surgery, SSMC Mitford Hospital with a sample size of 87 cases for a period of six months from 10 th February’ 2020 to 9 th August’ 2020. The patients with vocal cord lesions were selected according to the eligibility criteria by purposive sampling. Results : On indirect laryngoscopic examinations, 29.89% were vocal cord polyp, 16.09% suspected vocal cord neoplasm, 14.94% vocal cord edema, 11.49% vocal


Introduction:
Hoarseness is usually the earliest manifestation of conditions directly or indirectly affecting the voice apparatus.Usually it is the symptom of vocal cord lesions and should not be ignored if it persists more than 2 weeks or not responding to conventional treatment.Though most common causes of hoarseness are benign and vocal abuse is the commonest among them, but we should always exclude more sinister pathology like malignancy.Although many patients are examined with indirect laryngoscopy, this is not always conclusive and visualization is often poor.The areas which cannot be seen by indirect laryngoscopy are anterior commissure, laryngeal part of epiglottis and subglottis.Hoarseness is the term uses to describe a change in normal quality of voice which is caused by abnormal vocal cord movement. 1,2he hoarseness could be divided into acute or, chronic. 3The acute onset is more common and mainly caused by inflammation like acute laryngitis whereas other causes may be smoking, voice abuse, laryngeal trauma or thyroid surgery. 46][7] The complaints of hoarseness may imply serious disease like carcinoma of larynx, so it should not be ignored. 8Voice quality can be evaluated using the GRBAS (Grade, Roughness, Breathy voice, Asthenia and Strain) assessment.ENT assessment should include examination of the larynx by indirect laryngoscopy and fibreoptic laryngoscopy, stroboscopy and narrow band imaging. 10Fibreoptic Laryngoscopy (FOL) is the procedure by which larynx can be examined appropriately with adequate illumination and visualization.Findings can also be displayed with monitor and can be documented for furthur reference.
Fiberoptic imaging was initially developed to visualize inaccessible regions of the body.Current fiberoptic nasopharyngolaryngoscopes are lighted, are flexible with 2-way articulation, provide high resolutio photo and video capabilities, and can have a distal diameter as small as 2 mm 13 .Fiberoptic laryngoscopy is indicated when visualization of the nasopharyngolaryngeal anatomy is needed for diagnosis, treatment, or both as well as for follow up 14 .In the nasal cavity, fiberoptic laryngoscopy can visualize polyps, tumors, foreign bodies, or sources of epistaxis.In the nasopharynx, the scope can help identify suspected tumors or adenoidal hypertrophy 15 .In the oropharynx or hypopharynx, fiberoptic laryngoscope be used to evaluate foreign bodies and potential airway obstruction from such etiologies as neoplasm and also other pathologies like tonsillar hypertrophy, glossoptosis, or laryngomalacia 16 .
In the vocal cords-polyps, nodules, edema, sulcus vocalis, cyst, tumors both benign and malignant and impairment of their movement can be identified properly with fiberoptic laryngoscopy 17 .FOL is considered as a safe procedure with few contraindications and mild complications in experienced hands.Often it seems to be difficult to diagnose vocal cord lesions by conventional indirect laryngoscopy (I/L), especially when the lesion is at an early stage.In this situation fiber optic laryngoscopy (FOL) is very helpful.This study has been designed to compare fibreoptic laryngoscopy (FOL) and indirect laryngoscopy as a diagnostic tool for vocal cord lesions.

Materials and Methods:
Total 87 patients with vocal cord lesions studied in 06 months period from 10 th February' 2020 to 9 th August' 2020 in the Department of ENT & Head-Neck Surgery, Mitford hospital, Dhaka.The patients with vocal cord lesions were selected according to the eligibility criteria by purposive sampling.Then the data were collected by the active participation of the patients interviewed by the pretested data sheet, then data were gathered decorated and tabulated after data cleaning and edition in prospective method.The results were presented in graphical and tabulated form.

Table - I
: Age distribution of the study population (n=87)

Table IV :
Duration of change of voice (n=87) In this study, change in voice was found in all patients (100%).Other symptoms were vocal

Table VIII :
Chi-square test of indirect laryngoscopy (I/L) and Fibreoptic laryngoscopy (FOL) findings (n=87) A patient presenting with change of voice may have any of a wide range of pathological conditions including malignant lesion which may be aggressive.Therefore early diagnosis of the underlying cause becomes all the more important in every case.Study showed that many of the study subjects having poor vision and normal I/L findings had lesions on FOL.Some new lesions (e.g.laryngeal web) were also detected on FOL which were not detectable on I/L.Therefore, routine FOL evaluation is valuable and more accurate in the diagnosis of patients with vocal cord lesions causing voice change.It should always be considered in patients with persisting and progressive symptoms even though I/L appeared normal.