Optimizing Intra Ocular Pressure Control In Glaucoma: The Role Of Anterior Segment Biometric Changes After Cataract Surgery (A Prospective Ultrasound Biomicroscopy Study)

The purpose of this study was to evaluate the post-phacoemulsification changes in ocular biometric parameters, as determined by ultrasound biomicroscopy (UBM), and intraocular pressure (IOP), in a cohort of open angle glaucomatous patients undergoing uneventful cataract surgery.

A prospective cohort study was conducted, including 85 eyes of 85 individuals who underwent uneventful phacoemulsification with monofocal intraocular lens implantation. 

Ocular biometric parameters of the anterior segment were assessed using high-frequency ultrasound biomicroscopy, and intraocular pressure (IOP) was measured by Goldmann applanation tonometry, both preoperatively and at a 3-month postoperative follow-up. The correlation between postoperative IOP changes and ocular biometric parameters changes was then evaluated.

Postoperatively, no statistically significant changes were observed in the following parameters: IT, IZD, ICPD, and TCPD (P > 0.01). Conversely, central anterior chamber depth (ACD) demonstrated a significant increase of approximately 33% (P < 0.001). Furthermore, a statistically significant increase of approximately 42% in the anterior chamber angle was noted, by both measurement methods: AOD250 (P < 0.001), AOD500 (P < 0.001). The ISA also exhibited a significant increase of approximately 22% (P < 0.001). Intraocular pressure (IOP) was significantly reduced by 26% from baseline. Among different parameters, ACD demonstrated the strongest correlation with IOP reduction following cataract surgery (p = 0.003).

Following cataract surgery with monofocal intraocular lens (IOL) implantation, ultrasound biomicroscopy (UBM) revealed an increase in anterior chamber depth accompanied by an expansion of the iridocorneal angle. Thus, resulting in a reduction of intraocular pressure (IOP) and improved pressure control in patients with glaucoma.