[Cataract surgery in nanophthalmic eyes].

Purpose: The aim of this study was to determine the prevalence of nanophthalmos among cataract patients and to evaluate intraoperative and postoperative complications in nanophthalmic eyes.

Patients And Methods: Medical and operating records of all 3287 patients who had undergone clear cornea phacoemulsification cataract surgery with foldable acrylic IOL implantation during a period of two years (January 2009 to December 2010) were retrospectively reviewed. Nanophthalmos was diagnosed according to a shorter axial length than 20 mm, a shallow anterior chamber, hyperopia and scleral thickness greater than 1.7 mm as determined by echography. Before surgery all patients received an intravenous 20 % mannitol solution.

Results: From 3287 eyes, six eyes of four patients were identified as nanophthalmic with an axial length below 20 mm and a scleral thickness greater than 1.7 mm. The prevalence of nanophthalmos was 0.18 %. The average hyperopia was + 7.87 D (+ 6.0 to + 9.50). The mean axial length was 19.58 mm (18.94 to 20.00). The mean biometry calculation was 33.16 D (31.5 to 36.0). In all cases no complications were observed during the surgery. In two eyes a mild iritis was observed one day after surgery. During a follow-up of 3 months no further complications occurred.

Conclusions: Surgical manipulation in a narrow and crowded anterior chamber in nanophthalmic eyes with increased vitreous pressure is always a challenge and must be performed by an experienced surgeon. Preoperative examination of scleral thickness and preoperative administration of hyper-osmotic solution for reduction of vitreous pressure are very important to prevent unexpected complications. There was no need for a prophylactic surgical procedure in our patients.