Prostaglandin analogues in the anterior eye: their pressure lowering action and side effects.

Topical application of prostaglandin (PG) analogues are currently the most commonly used intraocular pressure lowering drugs in glaucoma. They have been available since the mid 1990's, and are efficacious and generally well tolerated, the compliance rates are good due to the once a day application regime. The mode of action of PGs is by increasing the aqueous humour outflow primarily via the uveoscleral route, and also (but to a lesser degree) the conventional trabecular meshwork pathway.

Morphometric effects of long-term exposure to latanoprost.

Purpose: To investigate the morphological and melanin granule changes in irides after variable-term exposure to latanoprost, where the latanoprost-induced iris darkening (LIID) side effect has been identified and photographically recorded.

Design: Experimental study.

Participants: Fifteen LIID cases and 15 untreated controls.

Melanin in the trabecular meshwork is associated with age, POAG but not Latanoprost treatment. A masked morphometric study.

We wished to conduct a light and electron microscopic investigation of pigmentation within the trabecular meshwork of normals and primary open angle glaucoma (POAG) patients. In particular we wished to get a precise determination of whether there was a relationship between pigmentation and age. In addition we wanted to know if there was a difference between normals and POAGs and whether trabecular meshwork hyperpigmentation was associated with topical latanoprost medication.

Latanoprost and pigmentation.

Latanoprost is a prostaglandin analogue with well-established efficacy in the treatment of open-angle glaucoma and ocular hypertension. Once-daily administration of this drug for up to 5 years is generally well tolerated both locally and systemically. While most reported side effects have been classified as mild in intensity, an increase in iris, eyelash, and periocular pigmentation has been associated with prostaglandin analogue use in some patients.

Latanoprost-induced iris darkening: a morphometric study of human peripheral iridectomies.

Purpose: This microscopic study was undertaken to compare the melanocytes of peripheral iridectomy specimens from two eyes that had latanoprost-induced iris darkening (LIID) with iridectomies taken from the fellow untreated eyes.

Methods: The two patients in this study were the ones who underwent LIID in the latanoprost treated eye from a series of 17 patients requiring bilateral trabeculectomy. The first trabeculectomy procedure provided a control peripheral iridectomy for each patient, whereas the second eye was treated with once daily 50 microg ml(-1) latanoprost drops for 6 months.

Histology and fine structure of the iris and outflow system following latanoprost therapy.

Latanoprost therapy can lead to iris darkening in susceptible individuals, particularly those with hazel eyes. Concerns have been raised about whether latanoprost, and for that matter other prostanoids, may have a harmful effect on the iris. In addition, it is unknown whether latanoprost causes increased pigmentation of the outflow pathways that might eventually lead to blockage and a type of pigmentary glaucoma.