Sadeer B. Hannush

Descemetic DALK and Predescemetic DALK: Outcomes in 236 Cases of Keratoconus

Purpose: To report the outcomes of our experience with deep anterior lamellar keratoplasty (DALK) in patients with keratoconus. Methods: A retrospective evaluation of 236 eyes of 198 patients that have undergone DALK between 2000 and 2006 using the Tsubota, Sugita, Melles, or Anwar technique. We analyzed the frequency of true Descemet membrane exposure, which we termed dDALK, and the number of eyes in which a predescemetic plane was achieved, which we termed pdDALK. Pre- and postoperative visual acuity, endothelial cell count, and central corneal thickness were evaluated on 120 eyes followed in our department. Results: A total of 139 of 236 (59%) eyes were classified as dDALK, with the Anwar technique showing the highest incidence of exposure of Descemets membrane (127 of 164, 77%). Descemet ruptures occurred in 25 of 236 cases (10.5%). Three ruptures were converted to penetrating keratoplasty (PK). There was no difference in visual acuity between the pdDALK and dDALK groups at an average follow-up of 30.4 months, although the eyes in the dDALK group seemed to have faster visual recovery. Best spectacle corrected visual acuity postoperatively was at least 20/30 in 80-85% of eyes at the patients last visit. Endothelial cell loss was 11-13%, with most of the loss occurring in the first 6 months. Conclusions: Performing DALK, we had the greatest likelihood of reaching Descemets membrane with the Anwar Big Bubble technique. The visual outcomes are comparable to standard PK, avoiding the risk of endothelial rejection. Endothelial cell loss was low and the cell count was stable after 6 months.

Long-term outcomes of Boston type 1 keratoprosthesis implantation: A retrospective multicenter cohort

PURPOSE To study the long-term outcomes of Boston type 1 keratoprosthesis (KPro) surgery. DESIGN Retrospective, multicenter case series. PARTICIPANTS A total of 158 eyes of 150 patients underwent KPro implantation at 5 participating tertiary centers in the United States between January 2003 and December 2006. Of those, 139 eyes of 133 patients were included in the analyses. METHODS The medical records of consecutive adult patients who received KPro surgery were reviewed. All patients with at least 1 postoperative visit were retained in the outcomes analyses. In eyes in which a repeat KPro procedure was performed, only the outcomes of the initial surgery were analyzed. MAIN OUTCOME MEASURES Visual acuity (VA) outcomes, postoperative complications, and device retention. RESULTS The mean follow-up was 46.7 ± 26 months with all but 4 eyes having at least 6 months of follow-up. Preoperatively, only 10.8% of the eyes had VA of ≥ 20/200. Postoperatively, the VA in 70% of eyes improved to ≥ 20/200. The probability of maintaining VA of ≥ 20/200 at 7 years was 50%. The device retention rate was estimated at 67% at 7 years. The 7-year cumulative incidence of complications was 49.7% for retroprosthetic membrane formation, 21.6% for glaucoma surgery, 18.6% for retinal detachment, and 15.5% for endophthalmitis. CONCLUSIONS Although the risk for complications with longer follow-up seemed to increase, this large multicenter cohort demonstrates favorable outcomes with KPro, with a large number of patients achieving and retaining useful vision over a 7-year period.

Elevated intraocular pressure-induced interlamellar stromal keratitis

PURPOSE To describe a series of cases (Elevated Intraocular Pressure Induced Interlamellar Stromal Keratitis (PISK)) that appears to be identical to post-laser in situ keratomileusis (LASIK) diffuse lamellar keratitis (DLK), but was present at a later time frame and was associated with a significant elevation of intraocular pressure (IOP). Unlike DLK, this syndrome is not steroid responsive, but resolves with a lowering of the IOP. DESIGN Retrospective, noncomparative, small case series. PARTICIPANTS The medical records of four LASIK patients with IOP-induced interface changes for the 1-year period March 2000 to March 2001 were reviewed retrospectively. MAIN OUTCOME MEASURE Slit-lamp appearance. RESULTS In the four cases presented, the slit-lamp findings and visual degradation appeared identical to DLK. All cases, however, presented outside of the first postoperative week and were not associated with any antecedent trauma. All four cases failed to respond to high-dose topical steroids. Significant IOP elevations were noted in all cases, and the interface changes responded dramatically to both a lowering of the IOP and a discontinuation or lowering of the topical steroids. CONCLUSIONS Elevated IOP-induced post-LASIK interface keratitis (PISK) is a poorly documented phenomena. Because the condition may be caused by or worsened by frequent topical steroids, early recognition is important. Treatment consists primarily of normalizing the IOP.

A novel mutation in the helix termination motif of keratin K12 in a US family with Meesmann corneal dystrophy.

PURPOSE Meesmann corneal dystrophy is an autosomal dominant disorder characterized by fragility of the anterior corneal epithelium. We have previously demonstrated that this disease can be caused by mutations in the genes encoding keratins K3 or K12, the major intermediate filament proteins expressed in corneal epithelial cells. Here, we have carried out mutation analysis in a United States kindred presenting with typical features of Meesmann corneal dystrophy. METHODS Exons 1 and 6 of the K12 gene (KRT12) were polymerase chain reaction amplified from the probands and control DNA and subjected to direct automated sequencing. RESULTS A heterozygous missense mutation 1300A-->G was detected in exon 6 of KRT12, predicting amino acid substitution 1426V in the helix termination motif of the K12 polypeptide. The mutation was confirmed in the proband and excluded from 50 normal individuals by restriction enzyme analysis of polymerase chain reaction products. CONCLUSION We report a novel mutation in a critical molecular overlap region of K12 in a United States family with Meesmann corneal dystrophy. The results confirm that mutations in the corneal keratins (K3 or K12) can underlie Meesmann corneal dystrophy.

Retrospective review of graft dislocation rate associated with descemet stripping automated endothelial keratoplasty after primary failed penetrating keratoplasty

Purpose: To report the rate of graft dislocation in patients who underwent Descemet stripping automated endothelial keratoplasty (DSAEK) after a previous penetrating keratoplasty (PKP). Methods: Institutional review board-approved, multicenter, retrospective chart review. Inclusion criteria included: prior failed PKP and subsequent DSAEK. The primary outcomes measured in this study were the presence of a graft dislocation, rate of rebubble, and graft attachment. Additional variables included: presence of a prior glaucoma drainage device, graft-to-host size disparity, number of sutures remaining in PKP, and stripping of the Descemet membrane at the time of DSAEK surgery. Results: Ninety patients (97 eyes) were included in the study. In 31% (30 of 97), the endothelial graft dislocated after surgery. All 30 cases required a rebubble except 1, which reattached spontaneously. Ninety-eight percent (95 of 97) of all grafts remained attached for the duration of the follow-up period. Only 2 eyes (2.2%) required repeat graft. Endothelial grafts dislocated in 67% of patients with glaucoma draining devices. The dislocation rate for grafts larger than the host was 12 of 49 (24%), equal to the host was 3 of 17 (18%), and smaller than the host was 8 of 19 (42%). Dislocations occurred in 5 of 21 (24%) of grafts with sutures remaining and 22 of 76 (29%) of those with all sutures out. Five of 12 (42%) cases of grafts performed without stripping the Descemet had dislocations. Conclusions: The graft dislocation rate in DSAEK procedures after PKP is comparable to that after primary DSAEK cases. Donor grafts that are smaller than the host PKP and the presence of prior glaucoma drainage devices are risk factors for higher rates of graft dislocation.

Textural interface opacity after descemet stripping automated endothelial keratoplasty: a report of 30 cases and possible etiology.

Purpose: Descemet stripping automated endothelial keratoplasty (DSAEK) has its own set of complications including interface abnormalities. This case series presents the largest number of patients who developed textural interface opacity (TIO) at the graft–host interface after DSAEK. Methods: This is a retrospective multicenter case series of 30 patients from 7 institutions with the finding of TIO. Clinical information collected included donor preparation details, recipient information, and surgical technique. Clinical outcomes included best-corrected visual acuity and status of TIO appearance at the last follow-up visit. Slit-lamp photographs were analyzed and compared. Results: The majority of the patients (73%) had a best-corrected visual acuity of 20/40 or better. Four of the donor tissues were prepared with a microkeratome blade with the same lot number. Six patients had a central interface space between host and donor stromal surfaces—presumed interface fluid but potentially viscoelastic. A slight majority (57%) of patients had improvement in the severity of TIO, with 20% noted to have a complete resolution of TIO (mean follow-up of 11.9 months). Two clinical types of TIO were seen: an elongated type and a punctate type. Conclusions: Most patients with TIO after DSAEK obtain good visual outcomes. TIO spontaneously improves or even resolves during follow-up without intervention. The etiology of this condition is unknown, but we propose 2 different mechanisms. The elongated type could be secondary to an irregular cut of the donor with the microkeratome blade. The punctate type may be secondary to retained viscoelastic.

Late-onset deep infectious keratitis after descemet stripping endothelial keratoplasty with vent incisions.

Purpose: To report the clinical and histopathological findings of 3 cases of late-onset deep infectious keratitis after Descemet stripping endothelial keratoplasty (DSEK) with vent incisions. Methods: From a retrospective review of 150 consecutive patients who underwent uncomplicated DSEK with vent incisions, 3 patients developed late-onset deep infectious keratitis. Results: In case 1, the patient suffered a Pseudomonas corneal ulcer at the nasal vent incision after a dacryocystorhinostomy with stent, 16 months after DSEK. In case 2, a Streptococcus pneumoniae infection developed at the inferior vent incision from a spastic entropion 3 months after surgery. In case 3, an Enterococcus faecalis corneal ulcer presented as a deep stromal abscess in the nasal vent incision 7 weeks after DSEK. All cases required full-thickness penetrating keratoplasties. Visual acuities at the last follow-up were counting fingers (case 1), 20/80 (case 2), and 20/400 (case 3). Conclusions: Vent incisions in DSEK may allow bacterial keratitis to penetrate deeply leading to aggressive keratolysis. One must be cautious in using vent incisions in patients with increased bacterial flora and patients with poor ocular surface healing from systemic, local, or mechanical conditions. If vent incisions are performed, a midperipheral oblique incision, parallel to the limbus, with meticulous detail to wound construction is recommended.

Classification of Corneal Topography with Videokeratography

The topography of the cornea has been imaged for over a century. The popularity of refractive corneal surgery in the past decade has emphasized in a practical way the need for accurate and reproducible methods of measuring the power of the entire corneal surface. The comparative usefulness of keratometry, photokeratography, and videokeratography are now matters of active study. We have used videokeratography to study the topography of normal corneas and of those that have undergone radial keratotomy and penetrating keratoplasty. We summarize our findings in this chapter.

Outcomes After Descemet Stripping Automated Endothelial Keratoplasty in Patients With Glaucoma Drainage Devices.

Purpose: To evaluate outcomes after Descemet stripping automated endothelial keratoplasty in eyes with glaucoma drainage devices. Methods: This is a retrospective review of 24 cases performed by a single surgeon (S.B.H.) on 20 eyes. Data were gathered on demographics, ocular history, surgical details, and postoperative outcomes. Outcome measures included primary graft failure, secondary graft failure, endothelial cell density (ECD), central corneal thickness (CCT), intraocular pressure, and visual acuity. Results: With a mean follow-up of 30.3 ± 19.6 months, there was no occurrence of primary graft failure, and the rate of secondary graft failure was 29%. Survival rates at 1, 2, and 3 years, respectively, were 87% [95% confidence interval (CI): 65%–96%], 80% (95% CI: 55%–92%), and 70% (95% CI: 39%–88%). Compared with ECD of the donor lenticule, endothelial cell loss was 49 ± 16% (n = 21) at postoperative month 3, 59 ± 16% (n = 20) at month 6, 61 ± 20% (n = 16) at month 12, and stabilized at 75 ± 17% (n = 9) by month 18. Compared with CCT during the visit before surgery, CCT decreased to 83 ± 18% (n = 18) at postoperative month 3 and gradually increased to 95 ± 11% (n = 6) at month 24. There were 4 (17%) cases of intraocular pressure elevation above 25 mm Hg. Improved visual acuity occurred in 71% of patients. Conclusions: Descemet stripping automated endothelial keratoplasty in eyes with corneal edema secondary to endothelial dysfunction in the presence of a previous glaucoma drainage device is a successful procedure. However, intermediate term endothelial cell loss is significant, as is the graft failure rate.

Epithelial-defect-masquerade syndrome after laser in situ keratomileusis ☆ ☆☆

Purpose: To describe a potentially serious complication of laser in situ keratomileusis (LASIK) that can masquerade as a persistent epithelial defect. Setting: Refractive surgery centers in academic institutions. Methods: Charts of 4 eyes in which epithelial‐defect‐masquerade syndrome was diagnosed were reviewed to determine the time to diagnosis and the presence of associated features that may have contributed to the delay in diagnosis. Clinical findings and outcomes of medical and surgical intervention were recorded. Results: All eyes developed an epithelial defect involving the edge of the flap during surgery. The diagnosis of epithelial ingrowth was delayed because of the presence of stromal edema (n = 4), diffuse lamellar keratitis (n = 3), and contraction of the flap leading to gutter widening (n = 4). Epithelial ingrowth was diagnosed 5, 7, 15, and 60 days after LASIK. All eyes satisfied the following criteria: convexity of the peripheral epithelium at the edge of the flap associated with light reflections at the end of the flap, fluorescein pooling in the gutter, stromal edema, reduced best spectacle‐corrected visual acuity (<20/60 in 3 eyes), and partial healing of the epithelial defect limited to the flap hinge. One eye developed stromal scarring and ulceration that required fortified antibiotics. Surgical repair included epithelial scraping after the flap was lifted and ironing followed by placement of a contact lens after surgery. The epithelial defect healed 5, 7, 21, and 24 days after surgery. The final uncorrected visual acuity ranged from 20/15 to 20/100. Conclusions: Epithelial ingrowth following LASIK‐associated epithelial defects may masquerade as stromal edema associated with a persistent epithelial defect. A high index of suspicion for epithelial ingrowth is essential to avoid a delayed diagnosis, which can result in irreversible visual loss due to stromal melting and infectious keratitis.