Ilse Claerhout

Delay in diagnosis and outcome of Acanthamoeba keratitis

PurposeTo evaluate the outcome of Acanthamoeba keratitis with respect to the delay in diagnosis.MethodsA retrospective review of the records of 14 patients treated for Acanthamoeba keratitis was carried out. Delay in diagnosis was correlated with risk factors, clinical presentation, method of diagnosis, final visual acuity and need for penetrating keratoplasty.ResultsBased on the time interval between the first symptoms and the diagnosis of Acanthamoeba keratitis, it appeared that patients could be divided into two groups: an early treatment group (group I), consisting of six patients treated within 18 days of onset of symptoms, and a late treatment group (group II), composed of eight patients treated beyond that time. There were no statistically significant differences between the two groups as far as risk factors, clinical presentation, accuracy of diagnosis and method of diagnosis were concerned, although more extensive and deeper corneal involvement was noted in group II. Improvement in visual acuity following medical therapy was seen in all six patients in the early group and in three (37%) of the eight patients in the late group. One patient in group I needed urgent penetrating keratoplasty for corneal necrosis. In group II, two patients underwent penetrating keratoplasty à chaud to prevent corneal perforation and three patients needed penetrating keratoplasty to restore functional visual acuity.ConclusionA diagnostic delay of less than 18 days between onset of symptoms and start of anti-amoebic treatment results in a better final VA after medical treatment and obviates the need for urgent and elective penetrating keratoplasty.

Therapeutic penetrating keratoplasty: clinical outcome and evolution of endothelial cell density.

Purpose. To identify the influence of the underlying etiology on the outcome of therapeutic penetrating keratoplasty (PKP) in the management of corneal perforation, impending perforation or refractory corneal disease. Methods. A retrospective observational case series with 28 patients (28 eyes) was performed. Patients were divided in two subgroups, based on the underlying ocular disease leading to the therapeutic PKP. Group I consisted of 15 patients (54%) with an infectious etiology, the other 13 patients (46%) with a noninfectious condition belonged to group II. Mean follow up was 23.2 months (median 21 months). Results. An enucleation could be avoided in all but two cases. In group I, 12 of 15 (80%) grafts remained clear, compared with only 3 of 13 (23%) in group II (p = 0.0004). Visual acuity (VA) amelioration was achieved in 20 of 28 patients (71%). In group I the postoperative VA was significantly better than preoperatively (p = 0.002); however, in group II the improvement was only borderline significant (p = 0.05). Overall five out of ten (50%) patients with a therapeutic PKP in group I had an endothelial cell density ≥ 1900 cells/mm2 at the time of their last specular microscopy. Conclusion. Our study demonstrates the importance of underlying etiology on the outcome of therapeutic PKP. Graft survival and postoperative visual acuity varied widely depending on the underlying ocular disease, and it was clear that therapeutic PKP has a much better prognosis in infectious conditions when compared with noninfectious conditions. We believe that these good results can justify the use of therapeutic PKP in selected cases of infectious keratitis.

Bilateral Corneal Melting in a Patient with Paraneoplastic Pemphigus

An 80-year-old man, with a solid abdominal tumor and multiple skin lesions, was admitted to the hospital because of a perforated right cornea and an impending perforation of the left. The clinical, histological, immunohistological and immunoprecipitation findings of the skin lesions were consistent with Anhalt’s criteria for paraneoplastic pemphigus (PNP). The underlying malignancy proved to be an incurable peripheral neuronal shaft tumor. Both conjunctivae appeared normal. The right eye revealed a flat anterior chamber, due to a spontaneous, central corneal perforation. The central part of the left cornea had severely thinned, resulting in a descemetocele, which eventually perforated. Multiple surgical interventions were needed to restore the anterior chamber in both eyes. Although a causative association between PNP and corneal perforation could not be demonstrated, we think that corneal melting should be added to the list of ocular complications in patients with PNP.

Confirmation of ofloxacin precipitation in corneal deposits by microbore liquid chromatography-quadrupole time-of-flight tandem mass spectrometry

We investigated the corneal precipitate of a 6-year-old boy with vernal keratoconjunctivitis (VKC), treated with topical ofloxacin 0.3% eyedrops. Because of the extremely small sample amount (corneal scraping), a very sensitive and specific method was needed with the possibility of an unambiguous identification of ofloxacin, supposed to be present in the precipitate. In this respect, tandem Q-TOF mass spectrometry combined with micro LC (1 mm I.D.) was chosen. Confirmation of the presence of ofloxacin in the deposit was obtained by means of the characteristic product ion spectrum produced by CID. This clearly indicated that the precipitate, removed by corneal scraping from the 6-year-old boy with VKC, contained ofloxacin.

The effect of duration and timing of systemic cyclosporine therapy on corneal allograft survival in a rat model

Abstract. Background: Systemic cyclosporine A (CsA) remains a valuable treatment option in the prevention of corneal graft rejection, but the question of timing and duration of this systemic therapy remains unresolved. The effect of a pre- and postoperative dosing schedule, related to the expected moment of rejection, was examined in a rat model. Methods: All AO (strain) recipients of PVG grafts were assigned to the following treatment groups: Group 1 (controls), groups 2–5 (a postoperative treatment regimen of CsA for 5, 10, 15 and 30 days respectively) and groups 6 and 7 (CsA preoperatively for 5 days and postoperatively for another 5 or 10 days respectively). Corneal allografts were clinically evaluated and blood CsA levels were measured at various time points. Results: Untreated controls rejected their allografts after 13 days. Regression analysis showed a strongly significant positive correlation between graft survival time and duration of cyclosporine therapy. There was no difference in graft survival between groups 3 (CsA 10 days) and 4 (CsA 15 days). A pre-operative dosing schedule of CsA followed by postoperative treatment had no advantage over a solely postoperative treatment regimen. The moment of rejection was characterized by a low to undetectable CsA concentration. Conclusion: The present study demonstrates a significant influence of the duration of systemic CsA administration on allograft survival time. However, preoperative administration of CsA does not seem to have an additional influence on graft survival, which is in line with the biological evidence of the mechanism of action of CsA on the efferent arm of graft rejection.

Corneal deposits after the topical use of ofloxacin in two children with vernal keratoconjunctivitis

Topical fluoroquinolones are broad spectrum, bactericidal agents with activity against both Gram positive and Gram negative corneal pathogens. Single drug administration with topical fluoroquinolones has been effectively used in treatment of bacterial ulcerative keratitis. The drugs are safe, but a white crystalline deposit, that in most cases spontaneously dissolved, has been reported1–4 with ciprofloxacin 0.3% and norfloxacin 0.3%. Up to now this side effect has not been described with ofloxacin 0.3%. We present two children with severe vernal conjunctivitis who developed corneal deposits after use of ofloxacin 0.3% eye drops. ### Patient 1 A 6 year old boy with vernal keratoconjunctivitis (VKC) developed a painful right eye while on holiday. His ophthalmologist diagnosed a corneal ulcer and prescribed ofloxacin eye drops followed by ofloxacin ointment four times a day for 3 weeks, associated with prednisolone drops. As the inflammation in the right eye persisted, the child was referred to our department. Slit lamp examination revealed mild VKC and a corneal ulcer with a …

Confocal microscopy of corneal crystals in a patient with hereditary tyrosinemia type I, treated with NTBC.

Purpose: To describe the confocal microscopic findings in a patient with hereditary tyrosinemia type I (HT-I) treated with 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC) who developed corneal crystals. Methods: In this case study, we describe the confocal microscopic findings in a boy, who was diagnosed with HT-I at the age of 4 months. At 16 years of age, he developed painful corneal lesions in both eyes. On slit-lamp examination, whorl-like branching epithelial corneal lesions were found, staining faintly with fluorescein. His NTBC treatment was stopped and reintroduced at a lower dose after 1 month. The lesions clearly regressed, leaving only mild residual epithelial scarring, without fluorescein staining and without pain. Confocal microscopy was performed in the acute painful stage and in the asymptomatic convalescent stage 5 months later. Results: Confocal microscopy confirmed the presence of slender birefringent spiky crystals in the very superficial corneal epithelium. In the asymptomatic convalescent phase, the crystals clearly persisted on confocal microscopy, although they were barely visible on slit-lamp examination. Conclusions: This is the first in vivo demonstration by confocal microscopy of corneal crystals present in a patient with proven type I tyrosinemia, under NTBC treatment.

Corneal manifestations and in vivo confocal microscopy of Gaucher disease.

Purpose: To report corneal abnormalities and confocal microscopy findings in a patient with a variant of Gaucher disease (GD). Methods: Case report with slit-lamp photography, confocal microscopy, and molecular analysis of the glucocerebrosidase gene. Results: Ophthalmic evaluation in a 57-year-old white patient demonstrated corneal opacities scattered throughout the cornea. Confocal microscopy revealed a completely distorted stromal architecture. The anterior part showed keratocytes with an abnormal morphology intermingled with minute white dots. In the posterior part, normal keratocytes were virtually absent and replaced by hyperreflective rod-like structures. Analysis of the glucocerebrosidase gene disclosed a heterozygous F216Y/L444P mutation. The patient’s old records revealed that these corneal abnormalities were already present at the age of 16 years, almost 15 years before the diagnosis of GD was made. His 2 siblings known with the same disorder and mutations also showed abnormal visual acuity and increased central corneal thickness. The confocal microscopy demonstrated some subclinical abnormalities, but otherwise normal corneas. Conclusions: Our patient had an unusual mutation responsible for his GD. Although corneal opacities are virtually unknown in GD, except in the D409H homozygous cardiovascular subtype, this patient had marked corneal stromal abnormalities.

Corneal opacification following keratoplasty in the rat model

I read with great interest the excellent perspective by Plskova et al ,1 in which they raise the issue of transient corneal opacification following corneal transplantation in the mouse model and argue that it might be due to a sufficient number of endothelial cells regaining function. What the authors describe for the mouse model also occurs in the rat model. In fact, most researchers on …

New aspects of the Slug Mucosal Irritation (SMI) assay: Detecting ocular stinging, itching and burning sensations

Purpose Our eyes are one of the most important senses. They are very sensitive and irritations may occur easily. A screening method for ocular discomfort would be very helpful in the development and refinement of formulations. In the past, the Slug Mucosal Irritation (SMI) assay demonstrated a relation between an increased mucus production (MP) in slugs and an elevated incidence of stinging, itching and burning (SIB) in human eyes. The aim of this study is to compare subjective ocular discomfort caused by shampoos evaluated in volunteers with results of the SIB‐procedure.