Richard L. Abbott

A Follow-up Study

: In 1983, Abbott et al. assessed endothelial cell population and function in 100 clear corneal grafts (72 patients) that were an average of 17.4 years postkeratoplasty. The present study reports on 61 of these grafts (42 patients) followed for an additional 4-6 years. Forty-nine grafts without intercurrent complications or surgery were reexamined by specular microscopy to determine the change in endothelial population in each graft. In 10 others, the reasons for regrafting were recorded. In two cases of hereditary stromal dystrophy, stromal opacity precluded a cell count. Of the grafts studied, 49 (80%) remained clear despite a depleted and slowly decreasing endothelial population. The rate of change was independent of donor age, preoperative diagnosis, or graft longevity. Two grafts failed spontaneously, and all three grafts that had cataract surgery failed in the early postoperative period. The remaining five were regrafted to correct high astigmatism or other complications. We conclude that despite a small degree of continuous cell loss, corneal grafts have a favorable prognosis for long-term clinical stability. The remaining endothelium has a minimal functional reserve, however, resulting in a high risk of graft decompensation after additional endothelial trauma.

The Incidence of Retinal Detachment Following Extracapsular Cataract Extraction: A Ten-year Study

A long-term prospective study was conducted to evaluate the incidence of specific complications following extracapsular cataract extraction. Eight hundred forty-two consecutive extracapsular cataract extractions were performed over a ten-year period with a minimum follow-up time of one year. The mean follow up period for this series was 32.2 months. The incidence of retinal detachment in the entire population was 1.4%. In those eyes with a cataract as the only ocular abnormality and with no surgical complications, the frequency was 1.0%. The incidence in eyes following uncomplicated procedures, with no other ocular pathology and with an intact posterior capsule was 0.8%. The incidence of opacification of the posterior capsule requiring capsulotomy was 16.7%. The mean time interval for a secondary capsulotomy was 24.3 months. A positive correlation between this time interval and patient age was established.

The prognosis for keratoplasty in keratoconus.

The long-term results in 326 eyes grafted for phakic keratoconus by the same surgeon were reviewed. All consecutive grafts performed for this disease with a minimum of five-year follow-up were included in the study. The mean follow-up was 11.3 years, with a range of 5 to 34 years. Ninety percent of grafts remained clear, 3% were nebulous but retained 20/40 vision, and 7% failed. Donor age was available for 188 of the 326 grafts. No relationship was found between donor age and long-term graft clarity even when older (more than 70 years) donor tissue was used. The visual acuity was measured with the patients preferred optical device worn daily. Seventy-three percent of eyes achieved 20/40 or better vision after their initial graft.

Two-year outcomes of intrastromal corneal ring segments for the correction of myopia ☆

OBJECTIVE To evaluate the safety and efficacy of Intrastromal Corneal Ring Segments (ICRS) for the correction of myopia. DESIGN Nonrandomized, comparative trial. PARTICIPANTS Patients enrolled in the United States Food and Drug Administration phase II and phase III clinical trials of the ICRS had best spectacle-corrected visual acuity (BSCVA) of 20/20 or better, myopia of -1.00 to -3.50 diopters (D), and a cylindrical correction of 1.00 D or less as measured by manifest refraction. INTERVENTION Surgical correction of myopia with an ICRS. MAIN OUTCOME MEASURES Efficacy was assessed by predictability of refractive outcome (deviation from predicted cycloplegic refraction spherical equivalent), stability of refractive effect, and postoperative uncorrected visual acuity. Safety was assessed by adverse events, maintenance or loss of preoperative BSCVA, and induced manifest refraction cylinder. RESULTS Four hundred fifty-two patients were enrolled at 11 investigational sites in both studies. Of the 454 surgical attempts, 449 received an ICRS in one eye (0.25, 0.30, and 0.35 mm in 148, 151, and 150 eyes, respectively). First surgeries were attempted in 452 patients. An ICRS was successfully implanted in 447 initial eyes, and 5 surgeries were discontinued. Of the five discontinued surgeries, three patients subsequently exited from the study, and two patients went on to have the ICRS implanted in the second eye, bringing the total number of successful implants to 449 patient eyes. Month 24 postoperative follow-up was completed on 358 patients (80%). At month 24, 328 of 354 eyes (93%) were within +/-1.00 D of predicted refractive outcome. Refraction changed by 1 D or less in 97% of eyes (421/435) between 3 and 6 months after implantation and in 99% (343/348) between months 18 and 24. Before surgery, 87% of eyes (390/448) saw worse than 20/40 uncorrected; 24 months after surgery, 55% of eyes (196/358) saw 20/16 or better, 76% (271/358) saw 20/20 or better, and 97% (346/358) saw 20/40 or better. Although two eyes (2/358; 0.5%) lost two or more lines of BSCVA at 24 months; visual acuity in both was 20/20 or better. Intraoperative complications included anterior corneal surface perforation (three eyes) and anterior chamber perforations (two eyes, one during an attempted exchange procedure); all healed spontaneously without suturing and without loss of BSCVA. The ICRS was repositioned in five eyes to increase correction. Postoperative complications in one eye each were infectious keratitis, shallow segment placement, and loss of two lines of BSCVA at two or more consecutive examinations (subsequently regained). CONCLUSIONS The ICRS safely, predictably, and effectively reduced or eliminated myopia of -1.00 to -3.50 D. The refractive effect was stable over time.

Long-term Changes in Corneal Endothelium Following Penetrating Keratoplasty: A Specular Microscopic Study

One hundred clear corneal grafts with a minimum follow-up of 10 years and average follow-up of 17.4 years were studied with specular microscopy. Central and peripheral graft endothelial cell counts as well as central corneal thickness measurements were done and these were correlated with the following parameters: diagnostic subgroups; donor age; graft age (follow-up time); and the postoperative clinical course. The average central endothelial cell counts for the entire series was 684 cells/mm2. Peripheral cell counts were performed in 78 eyes and averaged 749 cells/mm2. Central corneal thickness was measured in 80 eyes and averaged 0.49 mm. There were no statistically significant differences in central or peripheral cell counts when analyzing donor age, graft age, or postoperative course. When cell counts were examined among the diagnostic subgroups, those in the hereditary stromal dystrophy subgroup had a significantly lower cell density when compared to those in the keratoconus subgroup.

SPONTANEOUS CORNEAL HYDROPS AND PERFORATION IN KERATOCONUS AND PELLUCID MARGINAL DEGENERATION

Purpose. To report two cases of pellucid marginal degeneration and one case of keratoconus associated with spontaneous corneal hydrops leading either to perforation or imminent perforation, requiring urgent keratoplasty. Method. Retrospective interventional case series of three patients with noninflammatory peripheral corneal degenerations. A retrospective review was done of the clinical courses, surgical interventions, and pathologic specimens, development of spontaneous hydrops, perforation, need for surgical intervention, and final visual outcome. Results. Two patients with pellucid marginal degeneration and one with keratoconus developed spontaneous hydrops followed by aqueous leakage through markedly thinned anterior stroma. In one case, the leak site was successfully sealed after three separate applications of tissue adhesive, although the remaining two cases required penetrating keratoplasty. Conclusions. These cases document the very unusual occurrence of corneal hydrops leading to spontaneous corneal perforation in patients with keratoconus and pellucid marginal degeneration.

Intrastromal Corneal Ring Segments: Reversibility of Refractive Effect

PURPOSE To evaluate the reversibility of refractive effect following removal of the ICRS (intrastromal corneal ring segments; Intacs). METHODS Data from 34 eyes from which ICRS were removed during United States FDA Phase II and III clinical trials were evaluated with regard to segment size, loss or change of best spectacle-corrected visual acuity (BSCVA), any change of uncorrected visual acuity (UCVA), manifest spherical equivalent refraction, manifest cylinder refraction, stability of manifest cylinder refraction, and subjective visual symptoms. RESULTS Out of 725 initial or contralateral eyes placed with the ICRS during Phase II and III clinical trials, segments were removed from 34 eyes (4.7%). Other than one (1/725, 0.1%) safety related ICRS removal, 30/725 (4.1%) were due to visual symptoms. ICRS removal was accomplished under topical anesthesia without complications in all eyes. The mean length of time the segments remained in the cornea after initial surgery was 10.3 +/- 5.4 months. At 3 months after ICRS removal, 21 eyes had monitored data available and were within +/-1 line or 10 letters of their preoperative BSCVA. Twenty eyes (20/21, 95%) returned to within +/-1.00 D of their preoperative manifest spherical equivalent refraction. All eyes had a stable refraction at the 3-month examination after removal, and a manifest spherical equivalent refraction within +/-1.00 D of their 1-month examination after removal. Nineteen eyes (19/21, 90%) returned to within +/-2 lines and 16 eyes (16/21, 76%) returned to within +/-1 line of preoperative UCVA. CONCLUSION The ICRS (Intacs) was easily and safely removed, and eyes returned to preoperative refractive status within 3 months.

LATE-ONSET TRAUMATIC FLAP DISLOCATION AND DIFFUSE LAMELLAR INFLAMMATION AFTER LASER IN SITU KERATOMILEUSIS

Purpose. To report a case of traumatic flap partial dislocation and subsequent diffuse lamellar inflammation 14 months after laser in situ keratomileusis (LASIK) retreatment. Methods. Case report of a late flap dislocation that occurred during routine recreational activity (struck with a finger in the right eye while playing basketball). Results. The partially dislocated LASIK flap was reflected nasally, and the stromal surfaces of the flap and bed were thoroughly scraped to remove debris and epithelial cells. The flap was repositioned, and a bandage contact lens was placed. Diffuse lamellar inflammation, which developed on post-trauma day number two, was successfully treated with frequent topical steroids. Three weeks after the injury, the patient had regained 20/20 uncorrected visual acuity. Conclusions. Patients should be appropriately warned of the possibility of late flap dislocation with traumatic forces encountered during routine recreational activities. Full visual recovery is possible if the dislocation is promptly diagnosed and appropriately managed.

Minocycline-induced scleral, dental, and dermal pigmentation

PURPOSE To report a case of scleral discoloration secondary to minocycline therapy. METHOD Case report of a patient referred to a university-based cornea and external disease clinic. RESULTS The patient had been treated with oral minocycline therapy for adult facial acne for 12 years when she began to develop bilateral blue-gray discoloration of the sclera as well as of the teeth, hard palate, ears, nail beds, and skin. CONCLUSIONS Chronic systemic minocycline therapy may induce scleral pigmentary changes. The mechanism of discoloration and the long-term natural history upon cessation of minocycline are unclear.

A new mutation (Leu569Arg) within Exon 13 of the TGFBI (BIGH3) gene causes lattice corneal dystrophy type I

PURPOSE To describe an American family with lattice corneal dystrophy type I, which associates with a novel mutation, Leu569Arg, of the TGFBI (BIGH3) gene. DESIGN Experimental study. METHODS Genomic DNA was extracted from buccal epithelial cells of four affected members of an American family with lattice corneal dystrophy type I. All 17 exons of the TGFBI gene were evaluated by PCR amplification and direct sequencing. Clinical and histologic data were also collected. RESULTS Three generations of this family have been positively diagnosed with lattice corneal dystrophy, indicating autosomal dominant inheritance. We identified a heterozygous point mutation that associates with the disease phenotype. The single base-pair substitution (T1753G) results in an amino acid substitution (Leu569Arg) in exon 13 of the TGFBI gene. CONCLUSIONS Substitution of arginine for leucine at position 569 of the TGFBI gene results in a form of lattice corneal dystrophy that is phenotypically similar to other genetically distinct forms of type I disease. This is the first report of disease correlated with changes in exon 13 of the TGFBI gene.