Bradley D. Fouraker

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.

Recurrent corneal erosion: pathology of corneal puncture.

Despite conventional therapy, some patients continue to have episodes of erosion. Recent literature suggests the efficacy of corneal puncture, which is thought to induce adherence of the epithelium and basement membrane to the anterior stroma. We performed multiple corneal punctures with 23-, 25-, 27-, and 30-gauge needles on one patient who underwent penetrating keratoplasty 7 weeks later. We found that an insertion depth of 0.1 mm was sufficient to cause the production of new basement membrane and fibrocytic reaction in the anterior stroma. Analysis of the pathologic specimen supports the use of the larger 23- and 25-gauge needles, and cautions against the use of small gauge needles, especially 30-gauge, for this procedure.

Acute retinal necrosis associated optic neuropathy

Acute retinal necrosis (ARN) syndrome is characterized by severe intraocular inflammation, occlusive vasculopathy and peripheral retinal necrosis. Vision threatening complications of this syndrome include retinal detachment, macular oedema and ischaemia and optic neuropathy. Optic nerve involvement may be the presenting sign of ARN and this condition should be included in the differential diagnosis of acute papillitis. Several mechanisms may lead to ARN associated optic neuropathy including vasculitis, optic nerve ischaemia and direct optic nerve invasion by the herpes virus. We review optic nerve involvement during ARN and present its incidence, pathogenesis, differential diagnosis and treatment.

Use of a Mirror Needle Holder With Transsclerally Sutured Posterior Chamber Intraocular Lenses

A mirror needle holder has been designed to facilitate the passage of a needle through the ciliary sulcus during transscleral fixation of posterior chamber (PC) intraocular lens (IOLs). Two human postmortem eyes were used to demonstrate the efficacy of this mirror used as the needle holder. This method was compared with the current method of passing sutures without view of the ciliary sulcus. The mirror needle holder demonstrated precise passage of the needle into the ciliary sulcus by direct visualization of the ciliary processes and sulcus. This method may avoid the complications associated with transsclerally sutured PC IOLs during penetrating keratoplasty and secondary IOL placement.

Kyrieleis plaques associated with acute retinal necrosis from herpes simplex virus type 2.

PURPOSE To present the case of a 19-year-old woman with acute retinal necrosis syndrome due to herpes simplex virus type 2, who developed segmental periarterial (Kyrieleis) plaques six and one half weeks into her clinical course. METHODS Retrospective case report. PATIENTS Single patient with the diagnosis of acute retinal necrosis syndrome. RESULTS The patients vitreous biopsy was positive by polymerase chain reaction for herpes simplex virus type 2. DISCUSSION Kyrieleis plaques have been found in the setting of toxoplasmosis, tuberculosis, syphilis, rickettsial disease, herpes zoster virus, intraocular lymphoma, and idiopathic branch retinal artery occlusions. The differential diagnosis for these periarterial plaques should also include herpes simplex virus type 2.

Tampa Trephine Penetrating Keratoplasty

The Tampa Trephine penetrating keratoplasty technique (TTPK) provides a 7.0 mm corneal donor button with six rectangular tabs of Bowman’s layer and anterior stroma, 50 microns in thickness, which are inserted into the recipient corneal stroma beneath Bowman’s layer. TTPK offers the hypothetical advantages over standard penetrating keratoplasty of a more stable donor-host interface, the presence of fewer sutures (12 interrupted), lower astigmatism, a shorter visual acuity recovery period, and additional tectonic support in thin recipient beds. This article reports the results from the first 35 patients operated on within a four month follow-up period. The patients in this study were submitted to TTPK and evaluated postoperatively at 1, 7, and 15 days, as well as 1,2, 3, and 4 months. Retrospective evaluations included visual acuity, computerized corneal topography, ultrasonic pachymetry, slit lamp examination, and intraocular pressure. The tab presence induced a clinically stable donor-host interface by four months postoperatively. Early suture removal accomplished in nine cases in the postoperative time frame between 110 and 145 days reflected in minimal astigmatism only in three sutureless corneas. A myopic postoperative sphere was usually observed, especially when early complete suture removal was accomplished. Early postoperative complications included transient donor epithelial defects and corneal edema, inadequate wound closure, wound dehiscence, superficial neovascularization directed towards the tabs, epithelial inclusion in the stromal pocket, and contamination of the donor button. Late complications included one primary graft failure, one endothelial graft rejection, and one crystalline keratopathy.

THE EFFECTS OF THE TAMPA TREPHINE TECHNIQUE ON THE CAT CORNEAL ENDOTHELIAL MORPHOMETRY

eyebank (p=0.13). Positive cultures were more frequent for corneas excised in-situ (39/125, 31.2%) than for those enucleated (152/851, 17.9%), p<0.001. Three cases of endophthalmitis (0.28%) and one suture abscess occurred. Rim cultures were negative in all of these cases. Action was documented in response to positive cultures in 17 cases (8.1%). This included starting (4), restarting (4), increasing frequency of (2), or changing (2) topical antibiotic therapy, subconjunctival and intravenous antibiotic therapy (1), phone calls to patients (3) and extra clinic visits (5). The average estimated cost of routine rim cultures in 1994 was

Update on Epikeratoplasty

137 per donor cornea. Conclusions: Routine donor corneal rim cultures are of no clinical value in penetrating keratoplasty and are an unnecessary expense. Supported by NIH Grant EY02037, Research to Prevent Blindness Inc., and the Mayo Foundation.

One-Year Results of the Intrastromal Corneal Ring in Nonfunctional Human Eyes

Epikeratoplasty is a surgical procedure which modifies the surface topography of the cornea by the addition of a tissue lens. This procedure has been applied to patients with keratoconus, myopia, and aphakia. Several large studies of epikeratoplasty have been conducted which suggest that the procedure be limited to keratoconus and aphakic patients who are contact and spectacle lens intolerant.