Laurent Laroche

Bacterial keratitis: predisposing factors, clinical and microbiological review of 300 cases

Aim: To identify predisposing factors and to define clinical and microbiological characteristics of bacterial keratitis in current practice. Methods: A retrospective analysis of the hospital records of patients presenting with bacterial keratitis and treated at the Quinze-Vingts National Center of Ophthalmology, Paris, France, was performed during a 20 month period. A bacterial keratitis was defined as a suppurative corneal infiltrate and overlying epithelial defect associated with presence of bacteria on corneal scraping and/or that was cured with antibiotic therapy. Risk factors, clinical and microbiological data were collected. Results: 300 cases (291 patients) of presumed bacterial keratitis were included. Potential predisposing factors, usually multiple, were identified in 90.6% of cases. Contact lens wear was the main risk factor (50.3%). Trauma or a history of keratopathy was found in 15% and 21% of cases, respectively. An organism was identified in 201 eyes (68%). 83% of the infections involved Gram positive bacteria, 17% involved Gram negative bacteria, and 2% were polymicrobial. Gram negative bacteria were associated with severe anterior chamber inflammation (p=0.004), as well as greater surface of infiltrates (p=0.01). 99% of ulcers resolved with treatment, but only 60% of patients had visual acuity better than the level at admission, and 5% had very poor visual outcome. Conclusions: Contact lens wear is the most important risk factor. Most community acquired bacterial ulcers resolve with appropriate treatment.

Long-term Results of Deep Anterior Lamellar versus Penetrating Keratoplasty

OBJECTIVE To compare deep anterior lamellar keratoplasty (DALK) with penetrating keratoplasty (PK) in eyes with corneal diseases not involving the corneal endothelium (keratoconus, scars after infectious keratitis, stromal dystrophies, and trauma). DESIGN Retrospective, comparative case series. PARTICIPANTS One hundred forty-two consecutive DALK (DALK group; big-bubble technique or manual lamellar dissection using a slitlamp) and 142 matched PK (PK group). METHODS Three models were used to describe the postoperative outcomes of the endothelial cell density. A joint regression model was used to predict long-term graft survival. Visual acuity, ultrasound pachymetry, specular microscopy, and optical coherence tomography (OCT) findings were recorded. MAIN OUTCOME MEASURES Postoperative endothelial cell loss and long-term predicted graft survival. RESULTS The average 5-year postoperative endothelial cell loss was -22.3% in the DALK group and -50.1% in the PK group (P<0.0001). The early- and late-phase annual rates of endothelial cell loss were -8.3% and -3.9% per year, respectively, in the DALK group and -15.2% and -7.8% per year in the PK group (P<0.001; biphasic linear model). The median predicted graft survival was 49.0 years in the DALK group and 17.3 years in the PK group (P<0.0001). The average visual acuity was lower in the manual dissection subgroup compared with the PK group (average difference, 1.0 to 1.8 line) and with the big-bubble subgroup (average difference, 2.2 to 2.5 lines). The average central corneal thickness at 12 months was 536 μm in the PK group, 523 μm in the big-bubble subgroup, and 562 μm in the manual dissection subgroup (P<0.001). The average thickness of the residual recipient stroma measured by OCT was 87±26 μm in the manual dissection subgroup. No correlation was found between this figure and logarithm of the minimal angle of resolution at any postoperative time point (P>0.05). CONCLUSIONS Long-term, model-predicted graft survival and endothelial densities are higher after DALK than after PK. The big-bubble technique gives better results than manual dissection and PK. Compared with PK, manual dissection provides higher survival of both the corneal endothelium and graft, but lower visual acuity.

Predicted Long-term Outcome of Corneal Transplantation

OBJECTIVE To analyze graft survival and the outcome of the corneal endothelium after corneal transplantation in a single model to predict the long-term prognosis of these grafts. DESIGN Cohort study. Data were recorded prospectively and then analyzed retrospectively. PARTICIPANTS One thousand one hundred forty-four consecutive eyes of 1144 patients who underwent corneal transplantation between 1992 and 2006. INTERVENTIONS Penetrating keratoplasty and deep anterior lamellar keratoplasty. MAIN OUTCOME MEASURES Slit-lamp examination and wide-field specular microscopy results. A joint analysis of endothelial cell loss and time to graft failure was undertaken. From midterm simultaneous analysis of graft survival and endothelial cell loss, long-term graft survival was predicted. RESULTS The observed 5- and 10-year graft survival estimates were, respectively, 74% and 64%. The average endothelial cell density (cell loss) was 2270 cells/mm(2) before surgery, 1058 cells/mm(2) (-53%) during the sixth postoperative year, and 865 cells/mm(2) (-61%) during the 10th postoperative year. Overall, the predicted graft survival estimate was 27% at 20 years and 2% at 30 years. Both observed and predicted graft survival were higher in patients who had undergone lamellar keratoplasty than in patients who had undergone penetrating keratoplasty and had normal recipient endothelium and higher in patients who had undergone penetrating keratoplasty and had normal recipient endothelium than in patients who had undergone penetrating keratoplasty and had impaired recipient endothelium. CONCLUSIONS For corneal diseases involving the endothelium, penetrating keratoplasty seems to be a good therapeutic approach in elderly patients because the graft life-span may be similar to the patient life expectancy. Conversely, for younger patients, penetrating keratoplasty is only a midterm therapeutic approach. For corneal diseases not involving the endothelium, deep anterior lamellar keratoplasty seems to be a promising therapeutic approach with higher long-term expected survival.

Donor organ cultured corneal tissue selection before penetrating keratoplasty

AIMS Donor organ cultured corneal tissue selection before penetrating keratoplasty is carried out by taking into account different variables. The objective was to identify preoperative variables which are significantly and independently associated with transplant outcome and should effectively be taken into account before transplantation. METHODS 231 consecutive penetrating keratoplasties were prospectively studied using organ cultured tissue. Morphometric analysis of the donor corneal endothelium was performed before transplantation. Graft survival and endothelial cell density, during the second year following transplantation, were studied both at a univariate and multivariate level. RESULTS Recipient age, recipient rejection status, and preoperative diagnosis significantly influenced graft survival. Graft survival was higher when using corneal tissue from donors older than 80 years. Postoperative endothelial density decreased with preservation time and coefficient of variation after preservation. It increased with endothelial cell density after preservation and deswelling time, and correlated with preoperative diagnosis. CONCLUSION Organ cultured corneas with endothelial cell density after preservation <2000 cells/mm2, and high coefficient of variation, may be discarded before transplantation. Corneas should be preserved for less than 3 weeks, and allowed to deswell before transplantation for 2 or 3 days rather than 1 day.

In vivo confocal microscopy in fungal keratitis

Background: Fungal keratitis is a major blinding eye disease found throughout the world, particularly in developing countries. Given the recent increase in Fusarium keratitis infections in contact lens wearers owing to contact lens solutions, a warning was recently issued by the Food and Drug Administration, making it a public health concern in developed countries. Objective: To show the advantages of in vivo confocal microscopy imaging using the Heidelberg Retina Tomograph II-Rostock Cornea Module (HRTII-RCM) in the early diagnosis of fungal keratitis. Methods: HRTII-RCM confocal microscopy was performed on five patients presenting with fungal keratitis and on three donor corneas contaminated with Fusarium solani, Aspergillus fumigatus and Candida albicans. Results: Direct microscopic evaluation of corneal smears and culture revealed the presence of F solani in four cases and C albicans in one case. HRTII-RCM examination of the infected patients and contaminated donor corneas revealed numerous high-contrast elements resembling Fusarium, Aspergillus hyphae or Candida pseudofilaments in the anterior stroma. Conclusion: HRTII-RCM in vivo confocal microscopy is a new, non-invasive and rapid technique for the early diagnosis of fungal keratitis, showing high-resolution images resembling fungal structures in the early phase of the disease.

Evaluation of the deswelling period in dextran-containing medium after corneal organ culture.

Purpose To evaluate corneal structural modifications induced by the deswelling period in dextran-containing medium following organ culture. Methods Twenty human corneas were organ-cultured for 2 weeks and subsequently incubated in Exosol deswelling medium (Opsia, Toulouse, France) for 1–4 days. Corneas were studied by means of light microscopy, morphometry, and transmission electron microscopy. Results The deswelling period induced a statistically significant 8.4% endothelial cell loss and a 27.4% increase in the coefficient of variation. The endothelial layer remained intact. The basal epithelial cells displayed a flat appearance. Thin endothelial cells were observed in addition to dark vacuoles (the number of which increased with incubation time) with dense material and no mitochondrial swelling. Some basal epithelial cells and keratocytes were damaged on day 3 or 4. Conclusions Preservation injuries induced by 1 or 2 days of incubation in deswelling medium are moderate. Three or 4 days of incubation result in more severe dextran-induced injuries. Consequently, the deswelling period should not exceed 2 days.

Mechanized astigmatic arcuate keratotomy with the Hanna arcitome for astigmatism after keratoplasty

PURPOSE: To report the results of correction of post‐keratoplasty astigmatism by arcuate keratotomy performed with the Hanna arcitome (Moria). SETTING: Service 5, Hôpital des 15‐20, Paris VI University, Paris, France. METHODS: Forty eyes operated on for post‐keratoplasty astigmatism using the Hanna arcitome were retrospectively studied. Paired symmetrical arcuate keratotomies were performed on the graft button. Mean follow‐up was 10.8 months ± 11.2 (SD). Outcome measures included uncorrected visual acuity (UCVA), best spectacle‐corrected visual acuity (BSCVA), and subjective refraction. For statistical analysis, visual acuity data were transformed into logMAR units. The refractive data were analyzed using the Alpins method. RESULTS: By a mean of 10.8 ± 11.2 months after surgery, the UCVA had improved a mean of 0.28 ± 0.46 lines, which was significant (P = .013). The BSCVA remained stable. The mean subjective cylinder was 8.84 ± 3.00 diopters (D) preoperatively and 4.88 ± 2.50 D postoperatively (P<.001). The changes in postoperative subjective cylinder values correlated with preoperative cylinder values (rs = 0.584; P<.0001). The subjective axis was modified by 20 degrees or less in 27 eyes (67.5%). The mean surgically induced astigmatism was 8.07 ± 3.83 D and the mean correction index, 0.96 ± 0.46. One microperforation occurred and required suturing. Incisions were off center in 1 case, and 2 patients had an allograft rejection after the procedure. CONCLUSIONS: Arcuate keratotomy performed with the Hanna arcitome was effective in reducing post‐keratoplasty astigmatism. The device enabled safer, easier arcuate incisions than with manual techniques. However, predictability and efficacy could be improved by a more accurate nomogram.

Late bacterial keratitis after implantation of intrastromal corneal ring segments

We report a case of bacterial keratitis that occurred after implantation of intrastromal corneal ring segments (Intacs). The patient presented with decreased vision, inflammation, and stromal infiltrates localized at the extremity of an Intacs channel 3 months after surgery. Culture were positive for Clostridium perfringens and Staphylococcus epidermidis. The infiltrates progressed despite treatment with topical fortified and systemic antibiotics. The Intacs were removed. The keratitis slowly resolved, and the patient recovered a best corrected visual acuity of 20/20.

Microbiologic Study Of Organ-cultured Donor Corneas

BACKGROUND Our purpose was to evaluate the sterility of organ-cultured human donor corneas at the time of surgery. METHODS We studied 603 organ-cultured corneas. Of these 603 corneas, 409 (68%) were grafted and 69 (11%) were contaminated during storage. RESULTS Contamination during preservation was either bacterial (65%) or fungal (35%). None of the tested antibiotics were effective against all of the 45 isolated bacteria. The risk of contamination decreased with death-to-organ culture time (P=0.008) and was higher for corneas excised in situ than for those enucleated (P=0.02). Corneoscleral rims were sterile in 99.3% of the grafted corneas. Deswelling media were sterile in 100% of cases. A 19- to 53-fold decrease in the percentage of rim contamination was assessed with organ culture as compared with hypothermic storage (previous studies, P < 0.0001). CONCLUSIONS These results demonstrate the benefit of organ culture over hypothermic storage, because it allows contaminated tissue to be discarded.

Epiretinal membrane recurrence: incidence, characteristics, evolution, and preventive and risk factors.

Background: To evaluate the incidence, evolution, clinical characteristics, possible risk factors or preventive factors, and visual outcomes of epiretinal membrane (ERM) recurrence. Methods: Retrospective study of 440 consecutive patients (440 eyes) who underwent pars plana vitrectomy for ERM. The internal limiting membrane (ILM) was peeled in 266 cases, with the help of indocyanine green in 27 cases and brilliant blue in 45 cases. Cases of symptomatic ERM recurrence were reoperated. Results: The incidence of ERM recurrence was 5% (22/440), and 2% of the patients were reoperated (9/440). Epiretinal membrane recurrence was symptomatic in 9 cases (41%) and asymptomatic in 13 cases (59%). ILM peeling was the only factor preventing ERM recurrence (adjusted odds ratio = 0.33, P = 0.026). The use of staining dyes did not prevent recurrence (adjusted odds ratio = 0.35, P = 0.338). In the case of ERM reproliferation, the absence of ILM peeling, the existence of ERM on the fellow eye, and poor visual acuity before surgery seemed to be associated with a high risk of symptomatic recurrence and reoperation. The mean duration for follow-up was 3.5 ± 1.7 years. Conclusion: ILM peeling not only reduces the likelihood of reproliferation of ERM but also seems to improve the visual prognosis of recurrent ERMs. The use of dyes did not reduce the rate of recurrence compared with when ILM was peeled without dyes.