Cataract surgery in 79 patients with relative anterior microphthalmus (RAM): a review of anatomy, associated pathology and complications

Abstract

Naumann has coined the term relative anterior microphthalmus (RAM) for eyes with a dysproportional small anterior segment but no further malformation. Those eyes are characterized by corneal diameters of < 11 mm and total axial length of > 20 mm. To evaluate and define morphometrical data and risk factors for cataract surgery in patients with relative anterior microphthalmus (RAM) 112 cataract operations of 79 patients with RAM were analysed. Associated ocular pathology (such as glaucoma, previous surgical interventions, etc.) and complications of cataract surgery were recorded. Average corneal diameter was 10.7 +/- 0.34 mm, AC-depth was 2.20 +/- 0.49 and average lens thickness 5.05 +/- 0.45 mm. Fifty five percent of the patient revealed myopic refraction. There was a high incidence of glaucoma (77%), cornea guttata (46.6%) and Pseudoexfoliation syndrome (16%) in the RAM-group. Sixty percent of patients previously underwent glaucoma surgery. After cataract surgery 51.2% of patients achieved a visual acuity of > 0.5; 69.8% > 0.4. The IOP was preoperatively 16.5 +/- 5.8 mm Hg (with 1.3 +/- 1.4 antiglaucomatous drugs). Postoperatively IOP dropped significantly to 13.6 +/- 3.2 mm Hg (with significant reduction of treatment (0.6 +/- 1.0) (p < 0.01). The anterior chamber depth deepened from 2.42 +/- 0.47 mm to 3.33 +/- 0.72 mm. The special anatomical situation in RAM is responsible for the high incidence of glaucoma and postoperative complications after cataract surgery. Cataract surgery helps not only to restore vision but also facilitates handling and regulation of intraocular pressure.