Acetazolamide Likely Does Not Alter Optic Disc, Choroidal Vessel Density

Acetazolamide treatment administration does not result in significant alterations to optic disc, retinal, or choroidal vessel densities (VDs), according to research published in Archivos de la Sociedad Española de Oftalmología.

Researchers included 45 patients (mean age, 73.1 years; 23 men) in the observational cross-sectional study conducted between February and October of 2021 and orally administered 250 mg of acetazolamide 1 hour after participants underwent cataract surgery. Using optical coherence tomography-angiography (OCT-A), the investigators measured macular and choriocapillaris VD and optic disc radial peripapillary capillary VD prior to acetazolamide treatment and 1 hour following ingestion. 

Acetazolamide intake did not result in significant changes to the superficial or deep capillary plexus VDs in the fovea, parafovea, or perifovea (mean difference [MD] range, -077%-1.58%; P ≥.626 for all). Similarly, there were no changes in perifoveal, retinal nerve fiber layer (RNFL), or choroidal thicknesses (MD range, -0.09%-0.10%; P ≥.204 for all), the report shows.

The treatment, however, did increase mean foveal and parafoveal thicknesses compared with baseline (250.33 vs 248 µm; P <.001 and 311.98 vs 311.62; P =.046, respectively). It also significantly affected intraocular pressure (IOP) and systolic and diastolic blood pressures, decreasing them by 10.72% (P <.001), 4.90% (P =.021), and 4.72% (P =.030), respectively.

Foveal thickness was associated with superficial (r, 0.636; P <.001) and deep (r, 0.640; P <.001) capillary plexus VDs and nerve fiber layer thickness was associated with radial peripapillary capillary VD (r, 0.665; P <.001) and whole image (r, 0.679; P <.001), according to the report.

“One hour after its administration, [acetazolamide] was not found to have any significant vasodilatory effect on the retinal and choroidal microvasculature of the macula and the radial peripapillary capillaries with OCTA imaging,” according to the study authors. “It remains unclear if [acetazolamide] can affect glaucoma patients’ microvasculature.”

Study limitations include failure to evaluate higher doses of acetazolamide and non oral drug administration.