A comparative study on the effects of flexible and rigid laryngoscopy techniques on intraocular pressure

This study compared the impact of transoral rigid laryngoscopy (TORL) and transnasal flexible laryngoscopy (TNFL) methods on intraocular pressure (IOP).

This study included 100 patients, with 50 patients undergoing a TORL, and 50 patients a TNFL. Before procedure IOP values were recorded by an ophthalmologist using Icare Pro tonometry, also immediately post procedure, and at the 15th, 30th and 60th minute after laryngoscopy.

Both groups were similar in terms of age, gender, mean body mass index (BMI), and pre-laryngoscopy IOP values. When the TNFL and TORL groups were compared, no significant differences were observed between pre-laryngoscopy, and 60^th minute IOP values (p = 0.891, p = 0.149, respectively). IOP values measured immediately after laryngoscopy, and at the 15th and 30th minute were significantly higher in the TORL group (p < 0.001, p < 0.001, p = 0.002, respectively).

We demonstrated higher IOP fluctuations in the TORL group, when compared to the TNFL group. For this reason, TNFL may be considered a safer method for evaluating laryngeal tissues in conditions that require lower IOP fluctuation as in glaucoma. However, further studies are required to clarify the exact effects of IOP fluctuations during TNFL and TORL in patients with glaucoma.