Ilkka Lehto

Prospective evaluation of external ocularmicrobial growth and aqueous humor contamination during cataract surgery

PURPOSE To analyze the route of aqueous humor contamination leading to the development of postoperative endophthalmitis. SETTING Department of Ophthalmology, University of Helsinki, Finland. METHODS Forty-nine eyes of 49 patients (31 having phacoemulsification and 18 extracapsular cataract extraction [ECCE]) participated in the study. Four bacterial cultures were taken: preoperative conjunctival swab, lid margin culture, intraoperative lacrimal lake sample, and immediate postoperative anterior chamber fluid sample. RESULTS Preoperative lid margin cultures were positive in 59.2% of eyes, conjunctival cultures in 69.4%, and lacrimal lake cultures in 24.9%. Four aqueous humor samples (8.2%) showed bacterial growth in the anterior chamber aspirate: 3 in the phacoemulsification and 1 in the ECCE group. The bacteria isolated in this study, Staphylococcus epidermidis and Propionibacterium acnes (2 positive isolates each) were sensitive to the preoperative topical antibiotics used. No aqueous humor sample or any from other locations showed gram-negative microbe growth. The most frequently recovered microbes in all samples collected from the 3 other sources were S epidermidis and other coagulase-negative staphylococcus species, followed by P acnes and other propionibacterium species. Staphylococcus aureus, and diptheroids. CONCLUSION The ocular surface significantly contributed to the transmission of microbes into the eye during cataract surgery. These microbes could not be eradicated by topical preoperative antibiotics. However, no patient developed postoperative endophthalmitis. Natural defense mechanisms appear to fend off a minor inoculum with these microbes of relatively low pathogenicity.

Cellular and plasma fibronectin in the aqueous humour of primary open-angle glaucoma, exfoliative glaucoma and cataract patients.

Purpose To compare the concentrations of cellular fibronectin (cFN), plasma fibronectin (pFN), tenascin and calcitonin gene-related peptide (CGRP) in the aqueous humour in primary open-angle glaucoma (POAG), exfoliative glaucoma (EXFG) or cataract (control group).Methods The concentrations were determined by enzyme-linked immunoassays in the aqueous humour of patients with EXFG (n = 26), POAG (n = 29) or cataract (control group, n = 13).Results The pFN concentrations of the three patient groups differed significantly from each other (p = 0.0004 in a non-parametric analysis of variance). In multiple comparisons EXFG patients showed significantly higher pFN levels than POAG patients (p < 0.05) or cataract patients (p < 0.01). The cFN level was also significantly higher in EXGF patients than in POAG patients (p < 0.05) or cataract patients (p < 0.05). The pFN or cFN concentrations of the POAG group did not differ from those of the control group. Neither tenascin nor CGRP was detected in the aqueous humour of any of our patients.Conclusions The significantly higher aqueous humour pFN concentration in exfoliative glaucoma may be a consequence of disruption of the blood-aqueous barrier and may further add to an increased outflow resistance.

Corneal endothelium in pigmentary glaucoma and pigment dispersion syndrome

Abstract. Corneal endothelial cell density was determined in 64 eyes (32 patients) with pigmentary glaucoma and in 18 eyes (9 persons) with pigment dispersion syndrome without glaucoma. Twenty‐eight healthy eyes served as controls. The glaucomas were stabilized with topical treatment or following laser trabeculoplasty or filtration surgery. The mean duration of the glaucoma was 7.6 years (sd 6.1 years) subsequent to diagnosis. Neither in the glaucomatous, nor in the pigment dispersion syndrome eyes, could any statistically significant difference in cell density be noted compared to the control series. Within the glaucoma group pressure level, topical treatment, laser trabeculoplasty and trabeculectomy did not have any statistically significant effect on cell counts. Distinct pleomorphism and polymegatism of the endothelial cells were observed in the study groups. The endothelial cell density decreased linearly with age.

Diagnosis and management of pigmentary glaucoma.

Pigment dispersion syndrome and pigmentary glaucoma affect typically young, myopic persons. Iridozonular contact causes pigment dispersion and obstruction of the trabecular meshwork. Accumulation of pigment may result in transient elevation of intraocular pressure or irreparable damage to the meshwork accompanied by uncontrolled glaucoma. In the reviewed publications the transition from pigment dispersion syndrome to pigmentary glaucoma was found to be 20%. The main risk factors for the transition were ocular hypertension and myopia. Dapiprazole, an alpha-adrenergic blocking agent, was found to be effective in treating pigmentary glaucoma and in preventing pressure spikes after exercise. Dapiprazole causes miosis without affecting accommodation. Yttrium aluminum garnet laser iridotomy reduced the incidence of ocular hypertension in pigment dispersion syndrome, although the effect was less pronounced in persons older than 40 years of age. Lattice degeneration was found in 33.3% of the eyes with pigment dispersion syndrome.

Side effects of topical treatment in pigmentary glaucoma

Abstract. A series of 35 patients with pigmentary glaucoma were asked to report possible side effects of topical glaucoma medication using a multiple‐choice questionnaire. Of the 31 patients (89%) returning the forms, 22 (71%) were men and 9 (29%) women with a mean age of 45.1 years, range 23 to 72 years. The mean follow‐up time of their glaucoma was 10.7 years, range 2 to 30 years. A mild burning feeling (in 50% in all treatment groups) and redness of the eyes (in 42% treated with timolol alone and in 50% with timolol combined with dipivephrine, pilo‐carpine or both) were the main complaints, followed by a slight reduction of vision (in 17% in the timolol group and in 56% with combined treatment) and mild watering of the eyes (in 42% of the timolol and in 31% of the combined treatment groups). Twenty‐three percent of the patients did not have any side effects from their topical medication. Patients who admitted defaulting their topical treatment once a month amounted to 43% and once a week to 17%. Patients who admitted to never having missed a drop amounted to 40% of the sample; forgetful‐ness and haste were the main reasons for not applying the drops.

A Randomized, Prospective Study on the Use of Sodium Hyaluronate (Healon) in Trabeculectomy

The effect of injecting sodium hyaluronate (Healon) before fistulization in trabeculectomy was investigated in a prospective, randomized study of 107 consecutive eyes. Fifty-two eyes were operated on with the viscoelastic and 55 without. An early postoperative intraocular pressure (IOP) peak of 21 mm Hg or more occurred in 27% of the study eyes versus 17% of the control eyes, an insignificant difference. The mean peak IOPs of the study and the control eyes did not differ significantly (29.8 +/- 9.0 mm Hg versus 32.7 +/- 10.2 mm Hg), nor did the mean IOPs and the need for glaucoma medications 1 month after surgery. Shallow/flat anterior chamber and choroidal detachment were equally frequent in both groups, but hyphema occurred significantly more often in the study group (40%) than in the control group (18%).

Long‐term prognosis of pigmentary glaucoma

Abstract Outcome, prognosis and course of pigmentary glaucoma were studied in 38 patients (75 eyes). The mean age of the subjects at the time of diagnosis was 34.0 years and at the time of the study 44.1 years. The follow‐up time ranged from 2 to 30 years with a mean follow‐up time of 10.1 years. At the time of the study eighty‐nine percent of the eyes had normal vision (0.7 or better), 3% slight impairment of vision (0.6–0.3), 5% low vision (0.2–0.05) and 3% were blind. Visual field defects were mild in 78%, moderate in 13% and severe in 8% of the eyes. One eye (1%) had normal fields. In 8 patients the stage of the field defects was asymmetrical between the two eyes. All were able to read at least monocularly with glasses. No one was blind, retired early or professionally limited because of pigmentary glaucoma. Thirty‐nine eyes were on topical treatment. Fifteen eyes had additionally been treated with laser trabeculoplasty when the glaucoma could not be stabilized with topical treatment combined with systemic acetazolamide. Further twenty eyes had undergone trabeculectomy, 18 of them when medical treatment had failed and 2 following LTP. The non‐involved eye of a patient suffering from a monocular disease was without treatment. The mean intraocular pressure at the time of the diagnosis was 33.5 mmHg (sd 10.4 mmHg) and at the final visit 17.5 mmHg (sd 3.4 mmHg). Four eyes were operated for cataracts and one for retinal detachment. The outcome of pigmentary glaucoma in this study was that two patients (5% of the patients) were visually impaired in a socio‐economic sense because of field defects, one had cataract after trabeculectomy and one patient treated with pilocarpin for eight years had retinal detachment. One subject who had been treated with timolol for six years retired early due to asthma. The course and prognosis of pigmentary glaucoma seems to be quite favourable.