Influence of intraocular lens material on the development of acute endophthalmitis after cataract surgery?

PURPOSE: To investigate the causal relationship between acute postoperative endophthalmitis (POE) after cataract surgery and the biomaterial properties of the intraocular lens (IOLs) implanted. METHODS: This retrospective cohort study included all patients who had undergone cataract surgery with IOL implantation at the Lyon Croix-Rousse University Hospital between 1st January 1994 and 31st December 2004. Details respecting the type of IOL implanted (material and manufacturer) were meticulously recorded. The number of patients presenting with POE within 6 weeks of cataract surgery was documented together with their medical characteristics. These data were then compared, and Fisher's exact test was used to establish the significance of any apparent associations. RESULTS: Eight of the 5837 eyes manifested acute POE (0.14%). Seven of these were composed of polymethylmethacrylate (PMMA) and one of heparinized PMMA. Patients with PMMA IOLs carried a higher risk of developing POE than did those implanted with either heparinized PMMA (P=0.001), hydrophilic acrylic, or hydrophobic acrylic IOLs (P=0.002). CONCLUSIONS: The incidence of acute POE after cataract surgery in our hospital is similar to that currently reported for other institutions in developed countries. Our results add further evidence that IOL material and type are factors contributing to the risk to develop an acute POE after cataract surgery, and that PMMA IOLs may be associated with an increased risk of POE.

[Ultrasound biomicroscopy and physiopathology of congenital iris cysts]. / Ultrabiomicroscopie et physiopathologie des kystes iriens congénitaux.

AIMS: Iris epithelial cysts, congenital or acquired, are rare tumors of the anterior chamber. The use of ultrasound biomicroscopy (UBM) and high-resolution echography (50 MHz) specified the diagnosis and confirmed the developmental hypothesis. METHODS: UBM examination with general anesthesia can provide very good vision of cysts and iris structure similar to histological examination. Successive slices are systematically produced. We report two cases: one in a 3-month-old boy with a pupillary type of pigment epithelial cyst and one in a 23-month-old boy with stromal iris cyst provides new information on iris cysts. RESULTS: UBM can clearly differentiate two types of cyst, with results similar to histological slice examination. UBM slices of iris edge cysts show small cellular parietal groups with stromal echogenicity, with no visible tissular continuity. The stromal cyst has no particularity and no echogenicity. DISCUSSION: The pupillary type of pigment epithelial cyst was generally recognized very early. The great majority of primary iris cysts, particularly those that arise from the iris pigment epithelial layers, are stable lesions that rarely progress or cause visual complications. Their slow progression could be explained by embryological history. Based on a comparison between the aspects of the two observations, the absence of enlargement of the cyst could be explained by the developmental mechanism. CONCLUSION: The advantage of the UBM in diagnosis is confirmed for very young patients, but also in developmental investigations. These case reports also corroborate the migration cellular theory during eye development to explain the appearance of the pupillary type of pigment epithelial cyst.

[Conjunctival tumors in children. A histopathologic study of 42 cases]. / Tumeurs de la conjonctive bulbaire de l'enfant. Résultats de l'examen histologique de 42 lésions opérées.

PURPOSE: The aim of this study was to describe the clinicopathological characteristics of 42 conjunctival tumors surgically removed in children. PATIENTS AND METHODS: Records of all conjunctival tumors surgically removed in children during the 11-year period 1990-2001 were collected from the records of the Department of Ophthalmology, Edouard Herriot Hospital, Lyon. In all cases, the tumor was resected with no additional treatment. Sections of all cases were reviewed by the same pathologist. RESULTS: A total of 42 cases (40 patients) were included in the study. The mean age of the subjects at the time of surgical excision was 10 years, with a range of 1-17 years; 45% were male. The most frequent indication for tumor removal was suspected growth. The clinical diagnosis was accurate in 91% of cases. The tumor was localized at the limbus in 57% of cases. Most tumors were pigmented nevi, accounting for 83% of the lesions. The histopathological diagnoses in decreasing order of frequency were: nevi (35), angioma (2), dermolipoma (2), dermoid (1), papilloma (1), and squamous cell carcinoma (1). In one case, the histological study revealed squamous cell carcinoma in a child suffering from xeroderma pigmentosum. CONCLUSIONS: This retrospective study suggests that malignancy of pigmented conjunctival lesions is extremely rare in children. Although squamous cell carcinoma is rare in children, surgical excision and histological study are necessary when a conjunctival lesion is associated with xeroderma pigmentosum or immunodeficiency.

Toxic effects of indocyanine green, infracyanine green, and trypan blue on the human retinal pigmented epithelium.

BACKGROUND: Indocyanine green, infracyanine green, and trypan blue are frequently used as aids to visualize structures removed during vitreoretinal surgery. But they may have toxic effects on the retina. We therefore compared the acute and chronic toxicities of these stains on cultured human retinal pigmented epithelial (RPE) cells using clinically relevant concentrations and an identical experimental setup for each agent. METHODS: Monolayers of RPE cells were incubated with various concentrations of indocyanine green, infracyanine green (each at 0.005%, 0.05%, and 0.5%) or trypan blue (0.05%, 0.06%, 0.1%, 0.15%, and 0.5%) for 5 min (acute exposure) or 6 days (chronic exposure). Using the propidium iodide assay, acute cytotoxicity was monitored at 15-min intervals for up to 3 h. Chronic cytotoxicity was assessed by monitoring cell calcein esterase activity, cell proliferation, and cell morphology (viability) after 6 days of exposure. RESULTS: Indocyanine and infracyanine green induced acute and chronic toxicities at a concentration above 0.05%. Trypan blue evoked no acute toxicity, but it was chronically cytotoxic at all tested concentrations. CONCLUSIONS: Despite thorough rinsing after application, significant amounts of the not sufficiently water soluble indocyanine and infracyanine green are retained after surgery by the eye. Trypan blue, being more water-soluble than ICG, is probably retained to the least degree. This circumstance is fortunate given that trypan blue exhibits a chronic cytotoxicity comparable to ICG at all clinically relevant concentrations. During vitrectomy, surgeons should aim to expose retinal tissue to only low concentrations of these stains and for as short a period as possible.