Abstract
Purpose: :
To investigate the long–term outcome of phacoemulsification combined with viscocanalostomy (phacoviscocanalostomy) in eyes with medically uncontrolled glaucoma and co–existing cataract that suffered a perforation of the Trabecular–Descemet window (TDW) during surgery.
Setting: :
Department of Ophthalmology, Warrington Hospital, North Cheshire NHS Trust, Warrington, United Kingdom.
Methods: :
Phacoviscocanalostomy was performed on 165 eyes (114 patients) between 1997 and 2004. Fifteen (9.1%) eyes suffered perforation of the TDW (Perforation Group); the remaining 150 eyes did not suffer perforation of the TDW (Non–perforation Group). Examinations were performed preoperatively, at 1 and 7 days and at 1,3,6,9, and 12 months postoperatively and then in 6–month intervals. Outcomes measured were intraocular pressure (IOP) control, visual acuity and glaucoma medications.
Results: :
Follow–up was 39±19 months. IOP decreased significantly after surgery in both groups: in the Perforation Group, from 24.0±2.4 mmHg before surgery to 9.5±7.3 mmHg at day 1, 15.7±5.9 at 1 year, 14.6±2.1 at 4 years and 14.8±2.2 at last follow up (p<0.001); in the Non–perforation Group, from 24.1±5.3 mmHg before surgery to 14.2±8.1 mmHg at day 1, 15.9±3.6 at 1 year, 17.3±3.7 at 4 years and 16.4±3.6 at last follow up (p<0.001). Absolute success, defined as IOP ≤21 mmHg on no medication, was achieved in 93% of eyes at last follow up in the Perforation Group vs 85% in the Non–perforation Group (p=NS). Number of medications per eye decreased significantly in both groups: from 2.5±0.7 before surgery to 0.1±0.5 at last follow–up (p<0.001) in the Perforation group and from 2.5±0.9 to 0.1±0.6 (p<0.001) in the Non–perforation Group. IOPs less than 5 mmHg at day 1 were observed in 40% of the eyes of the Perforation Group vs 8.7% of the eyes of the Non–perforation Group (p=0.001). After 1 week, the IOP was above 5 mmHg in all eyes in both groups.
Conclusions: :
Phacoviscocanalostomy appears to be a safe and long–term effective IOP lowering procedure even in eyes that suffer perforation of the TDW. The results are encouraging for surgeons willing to learn this technique, as perforation of the TDW seems to be the most common complication encountered during intended non–penetrating Glaucoma surgery.
Keywords: trabecular meshwork • intraocular pressure • intraocular lens