Kristin M. Hammersmith

Boston keratoprosthesis outcomes and complications.

Purpose: To evaluate the outcomes of the Boston Keratoprosthesis (KPro) at our institution. Methods: A computerized database retrospectively identified all patients who received a Boston KPro from August 2005 to October 2007. Results: There were 37 patients, 24 (65%) were male. Mean age was 66.3 years (median 69 years, range: 24-93 years; SD = 18.1 years). Mean follow-up was 16 months (range: 6-28 months; SD = 6.0 months). There were 36 type 1 (97%) and 1 type 2 (3%) KPros. The primary indication was failed penetrating keratoplasty in 29 patients (78%)-22 (59%) from multiple failures. Preoperative comorbidities included glaucoma [27 patients (73%)] and limbal stem cell deficiency [13 patients (35%)]. No intraoperative complications occurred. Postoperative complications included retroprosthetic membrane [24 patients (65%)], increased intraocular pressure [14 patients (38%)], glaucoma progression [5 patients (13.5%)], and endophthalmitis [4 patients (11%)-3 who discontinued prophylactic antibiotics secondary to compliance]. Thirty-six KPros (97%) were retained-1 type 2 KPro (3%) in a patient with ocular cicatricial pemphigoid extruded and was replaced. Mean best-corrected visual acuities were counting fingers preoperatively (range: light perception to 20/100) and 20/90 at last follow-up (range: light perception to 20/25). At last follow-up, 31 patients (84%) improved 2 lines or greater-3 patients (8%) had worse vision. Conclusions: Retention rates were excellent, and best-corrected visual acuities improved in the vast majority of patients. Complications can occur and require frequent follow-up to monitor and treat glaucoma progression, endophthalmitis, and inflammation. Patient compliance is of paramount importance. Despite the potential complications, the Boston KPro provides visual improvement in patients with an otherwise poor prognosis.

Diagnosis and management of Acanthamoeba keratitis.

Purpose of review This paper reviews the literature generated on Acanthamoeba keratitis since 1998. Recent findings Acanthamoeba infections may be on the rise. Contact lenses are the biggest risk factor for their development. Silicone hydrogel lenses are increasingly prescribed and may be ‘more sticky’ to Acanthamoeba organisms. Orthokeratology for the treatment of myopia has been associated with many new cases of Acanthamoeba keratitis. Daily disposable contact lenses are the safest form of soft contact lens. Patients continue to be misdiagnosed as having herpetic keratitis. Impression cytology and confocal microscopy are newer diagnostic modalities. Topical polyhexamethylene biguanide, chlorhexidine and propamidine are the mainstay of medical therapy. Amniotic membrane may be used for cases of persistent epithelial defect and to control inflammation. Penetrating keratoplasty in a medically treated eye affords a good chance of positive outcome. Summary Acanthamoeba keratitis continues to be a difficult infection to diagnose and manage. The frequency of these infections may be on the rise, most commonly associated with frequent replacement soft contact lenses. The best chance for a good outcome is based on early diagnosis, so it is important for ophthalmologists consider it in patients, especially in the contact lens wearer with suspected herpes simplex keratitis.

Indications for Penetrating Keratoplasty and Associated Procedures, 2001–2005

Purpose. To identify current indications and trends in indications for penetrating keratoplasty (PKP) and associated procedures. Methods. Retrospective chart review of all patients who underwent PKP at Wills Eye Institute from January 1, 2001, to December 31, 2005. Results. A total of 1,162 cases were performed in this 5-year period. Leading indications for PKP were pseudophakic corneal edema (PCE) in 330 (28.4%) cases, followed by regraft in 250 (22.0%), keratoconus in 186 (16%), and Fuchs’ endothelial dystrophy in 126 (10.8%) cases. Of the 330 cases of PCE, 232 (70.3%) were associated with posterior chamber intraocular lenses (PCIOLs) and 96 (29.1%) with anterior chamber lenses. In 330 eyes with PCE, the lens was not exchanged in 246 (74.5%) cases and was exchanged in 76 (23%) cases. Seventy of the exchanged lenses were anterior chamber intraocular lenses (ACIOLs) and six lenses were PCIOLs. In cases of ACIOL exchanges, 10 were for scleral sutured IOLs, 18 for PCIOLS, and 42 for another ACIOL. Conclusions. Pseudophakic corneal edema remains the leading indication for PKP at our institution followed by regraft, continuing a trend noted in our previous studies. Although the percentage of cases of PCE associated with PCIOLS increased, fewer lenses were exchanged, perhaps reflecting increased confidence in biocompatibility of newer IOLs. The decrease in overall number of corneal transplants in these 5 years continues a trend noted in our previous study and mirrors the national decline in PKP.

Acanthamoeba keratitis: a parasite on the rise.

Purpose: To report a recent significant increase of the number of patients diagnosed with Acanthamoeba keratitis (AK) at Wills Eye Hospital between 2004 and 2005. To determine the risk factors, clinical characteristics, treatments, and outcomes of patients with AK. Methods: Retrospective consecutive case series of 20 eyes with AK. The information included the incidence from 1995 to 2005, initial and final best-corrected visual acuity (BCVA) at 3-month follow-up, risk factors [contact lenses (CL) history, history of swimming with CL, and exposure to well water and/or contaminated water], clinical characteristics, methods of diagnosis, and treatments. Results: A statistically significant increased incidence of AK was seen in 2004 and 2005 compared with cases from 1995 to 2003 (P < 0.01). All patients wore CL; 19 of 20 wore frequent-replacement soft CL and used multipurpose disinfecting solutions. Other risk factors were exposure to well water in 40%, swimming with CL in 25%, and overnight wear in 25%.The diagnosis was made by histopathology in 50%, by microbiology in 15%, and by initial classic clinical signs and response to treatments in 35%. Herpes simplex virus was the misdiagnosis in 70%. Patients who presented with dendritiform keratitis or radial keratoneuritis had a BCVA better than 20/30 in 8 of 9 (89%) and patients with ring ulcers or stromal disease who had a BCVA less than finger counting in 5 of 8 (62.5%). Conclusions: We observed an increased incidence of AK. Patients with proper use of frequent-replacement CL and multipurpose solutions can develop AK. Advanced stromal disease at diagnosis is associated with worse outcome.

Contact lens-related microbial keratitis: recent outbreaks.

Purpose of review This paper reviews the literature generated on atypical contact lens-related infections and their relationship with particular contact lens solutions since 2005. Recent findings Atypical soft contact lens-related infections are on the rise. Specifically, there has been an insurgence of Acanthamoeba keratitis and Fusarium keratitis. The rise in these infections was associated with Advanced Medical Optics Complete MoisturePlus (AMO, Santa Ana, California, USA) and ReNu with MoistureLoc (Bausch and Lomb, Rochester, New York, USA) respectively. Contact lens solutions in general are more effective against bacteria than fungal species or Acanthamoeba. Multipurpose solutions and no rub formulas may have diminished antimicrobial activity and are not as effective under real world conditions. Summary There have been epidemic increases in Acanthamoeba and fungal keratitis associated with particular contact lens solutions. Further study of these atypical species is necessary. Greater emphasis should be placed upon efficacy of contact lens solutions rather than ease of use.

Clinical and microbiological characteristics of fungal keratitis in the United States, 2001-2007: a multicenter study.

OBJECTIVE To study the epidemiology, clinical observations, and microbiologic characteristics of fungal keratitis at tertiary eye care centers in the United States. DESIGN Retrospective multicenter case series. PARTICIPANTS Fungal keratitis cases presenting to participating tertiary eye care centers. METHODS Charts were reviewed for all fungal keratitis cases confirmed by culture, histology, or confocal microscopy between January 1, 2001, and December 31, 2007, at 11 tertiary clinical sites in the United States. MAIN OUTCOME MEASURES Frequency of potential predisposing factors and associations between these factors and fungal species. RESULTS A total of 733 cases of fungal keratitis were identified. Most cases were confirmed by culture from corneal scraping (n = 693) or biopsies (n = 19); 16 cases were diagnosed by microscopic examination of corneal scraping alone; and 5 cases were diagnosed by confocal microscopy alone. Some 268 of 733 cases (37%) were associated with refractive contact lens wear, 180 of 733 cases (25%) were associated with ocular trauma, and 209 of 733 cases (29%) were associated with ocular surface disease. No predisposing factor was identified in 76 cases (10%). Filamentous fungi were identified in 141 of 180 ocular trauma cases (78%) and in 231 of 268 refractive contact lens-associated cases (86%). Yeast was the causative organism in 111 of 209 cases (53%) associated with ocular surface disease. Yeast accounted for few cases of fungal keratitis associated with refractive contact-lens wear (20 cases), therapeutic contact-lens wear (11 cases), or ocular trauma (21 cases). Surgical intervention was undertaken in 26% of cases and was most frequently performed for fungal keratitis associated with ocular surface disease (44%). Surgical intervention was more likely in cases associated with filamentous fungi (P = 0.03). Among contact lens wearers, delay in diagnosis of 2 or more weeks increased the likelihood of surgery (age-adjusted odds ratio = 2.2; 95% confidence interval, 1.2-4.2). CONCLUSIONS Trauma, contact lens wear, and ocular surface disease predispose patients to developing fungal keratitis. Filamentous fungi are most frequently the causative organism for fungal keratitis associated with trauma or contact lens wear, whereas yeast is most frequently the causative organism in patients with ocular surface disease. Delay in diagnosis increases the likelihood of surgical intervention for contact lens-associated fungal keratitis.

Voriconazole in the management of Alternaria keratitis.

To discuss the role of voriconazole in the management of Alternaria keratitis. Methods: Case report and literature review. Results: A 69-year-old man with a history of corneal foreign body removal developed a stromal infiltrate 2 months later that did not improve despite topical antibiotics and natamycin. On our initial examination, visual acuity (VA) was 20/40, and he had a central, full-thickness, reticular appearing infiltrate. Oral clarithromycin was added because of the atypical pattern of the infiltrate. However, no improvement was noted. A repeat culture revealed coagulase-negative Staphylococcus. VA decreased to 20/200, and increased inflammation was noted a month later; a trial of topical steroids was added. After an initial improvement, he returned with progression. Repeat culture revealed Alternaria species, and topical amphotericin was started. When there was no response, he was admitted and switched to oral and topical voriconazole. Steady resolution was noted within 10 days of therapy. Conclusion: Suspicion must be maintained for unusual causes of infectious keratitis. Fungal infection can be difficult to eradicate even with traditional antifungals. Although not approved for ophthalmic use yet, voriconazole provided improvement with Alternaria keratitis unresponsive to amphotericin.

An outbreak of Fusarium keratitis associated with contact lens use in the northeastern United States.

Purpose: To report an outbreak of Fusarium keratitis in contact lens (CL) wearers in the northeastern United States. Methods: Over a 41-month period, all cases with culture-proven corneal ulceration secondary to Fusarium at 2 tertiary care eye centers were identified through the microbiology departments of each institution, and a retrospective review of charts was performed. Statistical analyses were performed to evaluate a possible association of Fusarium keratitis with specific CL and CL solution brands. Results: Fifteen cases of Fusarium keratitis were reported at the 2 tertiary centers between July 2005 and May 2006 (16.4 cases/yr) compared with 6 cases over the previous 30 months from January 2003 to June 2005 (2.4 cases/yr). All 15 of the more recent cases were CL users, and none had a history of trauma. All 15 patients claimed use of ReNu brand contact lens solution when they developed keratitis. Twelve (80.0%) of 15 patients were Acuvue soft contact lens users. Ten (66.7%) of 15 patients used tap water to rinse their contact lens cases. Six (40.0%) of 15 cases have thus far required corneal transplantation. Conclusions: The incidence of corneal ulceration secondary to Fusarium has increased sevenfold over the reported 11-month period at 2 tertiary eye care centers in the northeastern United States compared with the previous 30 months. There seems to be an association between the recent outbreak of Fusarium keratitis among CL users and the use of ReNu contact lens solution. Medical treatment of Fusarium keratitis may be ineffective, and emergent penetrating keratoplasty (PKP) may be required in some patients. CL users and their physicians should reconsider the risks of CL use and discuss proper lens care techniques.

WOUND DEHISCENCE AFTER PENETRATING KERATOPLASTY

To assess the patient characteristics, risk factors, and outcomes of penetrating keratoplasty wound dehiscence. Methods: Retrospective chart review of 30 eyes of 29 patients with corneal grafts who underwent repair of penetrating keratoplasty wound dehiscence from January 1, 1998 to December 31, 2003, followed on the Cornea Service at Wills Eye Hospital. Results: The mean time from penetrating keratoplasty to wound dehiscence was 7.5 years (range 1 week to 31 years). The mean age at time of wound dehiscence was 66 years (range 28-98 years). One eye developed wound dehiscence following suture removal, whereas the remaining 29 eyes sustained trauma-induced dehiscences. Falls were the most common mechanism of trauma, especially in the elderly population. There was a wide range of visual outcomes in the 21 patients followed for 1 year, with 4 patients maintaining best corrected visual acuity between 20/20 and 20/40 and 5 patients with light perception vision at 1 year. There were no cases of endophthalmitis. Conclusions: Patients with corneal transplants have a life-long risk for wound dehiscence. This complication may be reduced by the regular use of eye protection in all corneal transplantation patients.

Referrals to the Wills Eye Institute Cornea Service after laser in situ keratomileusis: Reasons for patient dissatisfaction

PURPOSE: To review the symptoms, findings, and management options in patients referred to the Cornea Service who were unsatisfied with results after laser in situ keratomileusis (LASIK). SETTING: Cornea Service, Wills Eye Institute, Philadelphia, Pennsylvania, USA. METHODS: A retrospective chart review was conducted of all patients seen for consultation between January 1, 2004, and December 31, 2006, who had LASIK performed elsewhere. The parameters extracted were demographic data, history, symptoms, postoperative best corrected and uncorrected visual acuities, surgical complications, examination findings, and treatment recommendations. The data were also compared with previously unpublished data collected at Wills Eye from 1998 to 2003. RESULTS: One hundred fifty‐seven eyes of 109 patients seen in consultation after LASIK were identified. Twenty‐eight percent were referred by the LASIK surgeon and 54%, by another eye doctor; 17% were self‐referred. The most common chief complaints were poor distance vision (63%), dry eyes (19%), redness/pain (7%), and glare and halos (5%). Forty‐four eyes (28%) had surgical complications or enhancements. The most common diagnoses were dry eye or blepharitis (27.8%), irregular astigmatism (12.1%), and epithelial ingrowth (9.1%). Eleven percent were referred in the first month after LASIK; 23% and 10% were referred between 1 and 6 months and 7 and 12 months, respectively. Medical management (eg, artificial tears, steroids, other dry‐eye treatment) was offered in 39% of cases, surgical intervention in 27%, and observation only in 7%. Nonsurgical therapy was offered in 73% of cases. CONCLUSIONS: Most patients who came for consultation were referred by a doctor other than their LASIK surgeon. Poor distance vision, dry eye, redness/pain, and glare and halos were the most common chief complaints and dry eye or blepharitis, irregular astigmatism, and epithelial ingrowth, the most common diagnoses.