Method for Horizontal Calibration of Laser-Projection Transnasal Fiberoptic High-Speed Videoendoscopy

Objective: Calibrated horizontal measurements (e.g., mm) from endoscopic procedures could be utilized for advancement of evidence-based practice and personalized medicine. However, the size of an object in endoscopic images is not readily calibrated and depends on multiple factors, including the distance between the endoscope and the target surface. Additionally, acquired images may have significant non-linear distortion that would further complicate calibrated measurements. This study used a recently developed in vivo laser-projection fiberoptic laryngoscope and proposes a method for calibrated spatial measurements. Method: A set of circular grids was recorded at multiple working distances. A statistical model was trained that would map from pixel length of the object, the working distance, and the spatial location of the target object into its mm length. Result: A detailed analysis of the performance of the proposed method is presented. The analyses have shown that the accuracy of the proposed method does not depend on the working distance and length of the target object. The estimated average magnitude of error was 0.27 mm, which is three times lower than the existing alternative. Conclusion: The presented method can achieve sub-millimeter accuracy in horizontal measurement. Significance: Evidence-based practice and personalized medicine could significantly benefit from the proposed method. Implications of the findings for other endoscopic procedures are also discussed.

Surgical treatment of fourth branchial apparatus anomalies: a case series study

Background Fourth branchial apparatus anomalies, are rare clinical entities, and present as complex cysts, sinuses and fistulae in the neck that can be difficult to manage. Methods This is a retrospective review of a series of consecutive patients with fourth branchial apparatus anomalies treated at Department of Otolaryngology Head and Neck Surgery, Beijing Friendship Hospital, Capital Medical University, from Apr 2014 to Nov 2019. Results Ten patients with fourth branchial apparatus anomalies were identified, including 8 patients with fourth branchial fistula, and 2 patients with fourth branchial pouch sinus. There were 6 female patients and 4 male patients. Their age was from 6 years old to 39 years old (average age 20.4 years old, median age was 21 years old). All 8 fistulae were on the left side, while 2 pouch sinuses were both on the right side. Pre-operative examination with fiberoptic laryngoscope, barium swallow X-ray, CT or MRI identified internal orifice at pyriform fossa apex in 8 (80%) patients. All patients underwent challenging surgical resection by the senior author. Intra-operative direct laryngoscope confirmed or identified internal orifice in 9 (90%) patients. The tracts were all followed to the vicinity of inferior cornu of the thyroid cartilage and the cricothyroid space. Complete resection of cervical lesions and their attachment to hypopharynx were achieved in 9 cases. No complication occurred. One recurrence was detected, in the only patient whose internal orifice could not be located pre- or intra-operatively, and the hypopharyngeal attachment could not be removed. Conclusions Direct laryngoscopy under general anesthesia is a reliable method of diagnosis for the fourth branchial apparatus anomalies. Complete surgical removal of fourth branchial apparatus anomalies, including their hypopharyngeal attachment, is the treatment of choice, and the key to prevent recurrence.

A Case of Verrucous Carcinoma of Larynx

A 50 years old male patient was admitted with complaints of change in voice for 2 years, dry cough 2 month and difficulty in breathing for 1 month. On examination with fiberoptic laryngoscope, an exophytic lesion covered with whitish plaque involving right vocal cord extending from anterior commissure to right arytenoid region, extending upto the right vestibular area and hanging in the subglottic area was seen. Patient was treated with Microlaryngeal Laser excision and the Histopathology report was suggestive of Verrucous Carcinoma of Larynx. Bangladesh J Otorhinolaryngol; October 2017; 23(2): 208-211

Airway Management during Thyroidectomy for a Giant Goitre due to McCune-Albright Syndrome

There have been no case reports to date describing the technical aspects of tracheal intubation in a patient with a goitre associated with McCune-Albright syndrome (MAS), even though goitre is frequently observed in this condition. I describe a case of resection of a giant goitre in a patient with MAS, with difficult airway management. Preoperative investigation showed that the trachea was shifted to the right by the goitre, with the narrowest part of the tracheal lumen 4 mm in diameter. There was dome-shaped protuberance of the posterior pharyngeal wall into the airway. The patient had an S-shaped total spine, a short neck, and a relatively large jaw, which interfered with airway visualisation during intubation. Anaesthesia was induced with light sedation and supplemental oxygen. Endotracheal intubation was successfully performed using a fiberoptic laryngoscope and a flexible, spiral-wound, obtuse-tipped tracheal tube.