A Long Term Clinical Outcome Of Penetrating Keratoplasty And Scleral Fixated Intraocular Lens Implantation At Four Points Of Fixation By An Anterior Segment Surgeon

To analyze the surgical complexity, clinical outcomes and complications of 42 eyes of 42 patients, having a wide range of ages between 11 to 84 years, who underwent the surgery and had a long follow up (mean 2+/-2.216 years).

The preop conditions needing such surgery were: congenital pathology in 5 (11.9%), acquired in 37 (88%), pseudophakia in 15 (35.7%), aphakia in 23 (54.8%) and phakic 4 (55.8%). There were 33 (78.6%) male and 9 (21.4%) female patients, 24 (57.1%) were right eyes and 18 (42.9%) were left eyes. The commonest cause for intervention was trauma in 19 (45.2%), history of infection in 5 (57.1%), 21 (50%) had multiple surgeries in the past out of which 5 (11.9%) had prior retinal procedures.     

Two Hoffmann pockets were created, partial corneal trephination and 2 anterior chamber entries were made and anterior vitrectomy done if aphakic and the entry extended adequately. The lens was placed externally and its 2 eyelets were looped into 2 separate 10-0 prolene sutures that was taken through each pocket twice. Prolene suture ends trimmed, retrieved out of the pockets and partly secured. The lens was inserted and the sutures tightened furthermore. Penetrating keratoplasty was continued up to 8 anchoring sutures for good chamber formation, the lens sutures tightened, pockets glued and the graft was sutured completely. Procedures like, cataract surgery, IOL extraction, pupilloplasy or iridodialysis repair were done if needed.     

Clear graft was maintained in 20 (47.6%), graft rejection in 3, persistent edema in 1, eventual graft failure in 20, graft infection 2, endophthalmitis 1 and graft ectasia 3. The mean Visual acuity was 1.902 LogMAR pre-op and 1.802 LogMAR at final follow-up, excluding preexisting retinal pathologies corrected LogMAR was 0.52.  At last follow up vision improved in 18 (42.9%), maintained in 6 (14.3%) and worsened in 18 (42.9%), and patients needing more than -5.00 D spherical correction were 3 and -3.00 D cylinder power were 7. Glaucoma preexisted in 5, developed postoperatively in 10, 6 needed cyclodestructive and 3 valve surgery. Lens removal was done for 2 (4.7%) patients.

Combining scleral fixated lenses during penetrating keratoplasty simplifies the surgery with a wide open section not needing additional incision and direct lens positioning into posterior chamber. Hoffmann scleral pockets done through a limbal groove, can be done underneath intact conjunctival, thus preserving it for future glaucoma interventions that these complicated cases often require. Also, 4 points of fixation on the sclera gives added rotational lens stability. The fact that 20 had clear grafts, 18 visually improved, 2 needed lens removal and only one developed retinal detachment are encouraging, especially since the surgery was performed by a corneal surgeon. But longer follow up is needed to understand better.