The reculture technique: individualizing the treatment of Acanthamoeba keratitis.

PURPOSE: To assess the efficacy of three drugs in different concentrations against different strains of Acanthamoeba using the reculture technique. METHODS: Cysts and trophozoites were immersed in five separate solutions. The solutions administered included 0.1% and 0.02% polyhexamethylene biguanide (PHMB), 0.1% and 0.02% chlorhexidine, and propamidine isethionate (Brolene). Readings took place after 1, 5, and 24 hours. The cysts and trophozoites were then recultured for an additional period of 48 hours. An effective drug was defined as a medication that inhibited any growth of trophozoites using the reculture technique. RESULTS: Chlorhexidine at concentrations of 0.1% and 0.02% was the only effective drug against all five strains of Acanthamoeba examined, and no trophozoites were detected on plates immersed with this agent. Only 0.1% chlorhexidine was effective in destroying all cysts in the five strains examined. CONCLUSION: We found that 0.02% chlorhexidine was efficient in irradicating all trophozoites and 0.1% chlorhexidine was effective in eradicating all cysts in the samples we examined. Therefore, it may be possible that 0.02% chlorhexidine is a good initial treatment in amoebic keratitis. Sensitivity testing, then, may be performed using the reculture technique and specification of therapy can be made accordingly.

Increased intraocular pressure during treatment for chronic uveitis.

OBJECTIVES: (1) To prospectively evaluate the incidence of increased intraocular pressure (IOP) in patients suffering from chronic uveitis. (2) To identify the main factors responsible for an increase in the IOP among these patients. METHODS: Two hundred and one patients suffering from chronic uveitis were included. Enrolled patients had an initial IOP of 8-18 mmHg. The patients were treated and clinically monitored during a period of 4 years. The IOP was measured at each visit and its changes followed prospectively. All patients were followed up for at least 12 months after enrollment. RESULTS: Twenty-four (12%) of the 201 patients had IOP higher than 24 mmHg at two or more consecutive visits. Of these 24 patients, 19 suffered from bilateral uveitis and 5 had unilateral disease. Four of the 19 patients with bilateral uveitis developed a constant IOP higher than 24 mmHg in both eyes, while in 15 patients an IOP higher than 24 mmHg persisted only in one eye. A close association between the increased IOP and the use of corticosteroids was found in 18 of the 24 cases (75%). This association was ascertained in 16 of these patients by the decrease in IOP levels on discontinuation of the corticosteroid regimen and the renewed increase IOP was due to pupillary block in three cases (12.5%), to iris and angle neovascularization in two (8.3%), and to the inflammatory process per se in one case only (4.2%). CONCLUSIONS: This study demonstrates that a persistent elevation of the IOP in patients suffering from chronic uveitis is, in the majority of cases, associated with the use of corticosteroids.

Occult ocular damage as a leading sign in the battered child syndrome.

A three-month old, premature female infant is presented with severe bilateral occult ocular damage comprised of cataracts, lenses dislocation, retinal hemorrhages and total funnel-shaped retinal detachment without external signs such as bruises. This severe eye trauma is the result of child abuse. We would like to alert pediatricians as well as ophthalmologists that any ocular injury should raise the possible diagnosis of battered child syndrome even in the absence of other supportive evidence of external trauma.

The effect of sodium hyaluronate on the corneal epithelium. An ultrastructural study.

The effect of sodium hyaluronate (NaHa) 1% and 0.1% was studied on 14-day chick embryo corneal epithelium by scanning electron microscopy. It was found that NaHa 1% or 0.1% had no toxic effects on the chick corneal epithelium and the normal architecture of the cells and the morphology of the microvilli was well preserved. A combination of NaHa 0.1% and benzalkonium chloride (BAK) 0.01% reduced the toxic effect of BAK on the surface corneal epithelium. NaHa 0.1% provided a better protection of the corneal epithelium against dryness than hydroxyethylcellulose (HEC) 0.1% or phosphate buffer saline (PBS).

Intraocular involvement of Burkitt's lymphoma in a Bedouin child.

A child with a B-cell lymphoma with extensive abdominal disease responded to high doses of chemotherapy. One month later, eye and central nervous system recurrence developed. Intraocular involvement was documented by diagnostic vitrectomy. Differential diagnosis and therapy are discussed.