A variety of autoimmune diseases and allergic immune disorders correlated strongly with keratoconus , a study showed.

"The immune system has been implicated in the pathogenesis of keratoconus because thinning of the cornea seems to be associated with increased levels of intracorneal inflammatory mediators such as interleukin 1 ," the study authors said. "Moreover, allergic conjunctivitis, which results in a chronic inflammation of the ocular surface, has long been associated with keratoconus. On the other hand, autoimmune diseases, per se, have not been reported to be associated with keratoconus as a group or as separate entities."

The retrospective study included 426 patients with keratoconus and 1,704 age- and gender-matched controls. Patient data were culled from an electronic disease registry in Israel.

Study data showed statistically significant associations between keratoconus and rheumatoid arthritis ( P = .02), ulcerative colitis ( P = .03), autoimmune chronic active hepatitis ( P = .008), Hashimoto's thyroiditis ( P = .02), arthropathy ( P = .008), asthma ( P = .0008), irritable bowel syndrome ( P = .0005) and environmental allergy ( P = .04).

"A long list of other conditions was reported to be associated with keratoconus," the authors said. "For the most part, these associations should be considered to have occurred by chance. Some rare reports point to association between keratoconus and connective tissue disorders."

Highly active antiretroviral therapy has had a significant impact on the morbidity and mortality of patients infected with both AIDS and cytomegalovirus retinitis , but co-infection remains a significant cause of death, vision loss and other health Cornea. 2010; 29(11):1261-1264 complications, according to a study.

In a prospective, multicenter, observational study of 503 patients diagnosed with AIDS and CMV retinitis , overall mortality over a 5-year period was 9.8 deaths per 100 person-years. Within the study cohort, mortality rates ranged from a high of 26.1 per 100 person-years among individuals with newly diagnosed retinitis to a low of 3 per 100 person-years among individuals with previously diagnosed retinitis and immune recovery.

Retinitis progression was highest among patients with newly diagnosed disease (28 per 100 person-years) compared with individuals with previously diagnosed disease and immune recovery (1.4 per 100 person-years). Rates of retinal detachment, immune recovery uveitis and vision loss followed similar patterns.

"Patients with CMV retinitis remain at increased risk for mortality, retinitis progression, complications of CMV retinitis and visual loss for at least 5 years, even among those with immune recovery from HAART," the study authors said.

Ophthalmology . 2010; 117(11):2152-2161

Flap creation with a mechanical microkeratome or a femtosecond laser resulted in comparable increases in anterior corneal aberrations after myopic LASIK, a study found.

"After LASIK the cornea undergoes many changes, including delayed reinnervation, keratocyte loss and epithelial thickening," the study authors said. "These can affect corneal properties, such as topography and the corneal optical aberrations derived from it."

The prospective study included 98 eyes of 50 patients with a mean age of 31.8 years. Fifty eyes of 25 patients underwent flap creation with a mechanical microkeratome , and 48 eyes of 25 patients had flaps created with the femtosecond laser.

Patients underwent follow-examinations at 1 and 7 days and 1, 6, 12 and 48 months after surgery.

Study results showed that 43 out of 46 eyes in the microkeratome group (93.5%) and 41 out of 41 eyes in the femtosecond group (85.4%) had uncorrected distance visual acuity of 20/20 or better at 48 months after surgery. All eyes in both groups attained uncorrected distance visual acuity of 20/30 or better.

Thirteen eyes in the microkeratome group (28.3%) and 18 eyes in the femtosecond group (37.5%) had postoperative corrected distance visual acuity of 20/20 or better.

LASIK increased the root mean square of higher-order aberrations by a factor of about 1.9 in both groups. There were no statistically significant between-group differences in any Zernike coefficient with 4-mm or 6-mm pupil diameters, the authors reported.

Transconjunctival microincision vitrectomy and 20-gauge vitrectomy yielded similarly low rates of postoperative endophthalmitis , a large study found.

"A better understanding of possible causes of infection and conventionally standardized antiseptic protocols combined with specific techniques or suturing to facilitate rigid wound adaptation may account for this favorable trend in microincision vitrectomy surgery," the study authors said.

The retrospective survey included 43,868 cases that underwent vitrectomy at 27 centers between 2003 and 2008. The overall population comprised 29,030 eyes that underwent conventional 20-gauge vitrectomy, 6,600 eyes that had 23-gauge surgery and 8,238 eyes that had 25-gauge surgery. Mean follow-up was 25.3 months.

Study data showed that 10 eyes that had 20-gauge vitrectomy (0.034%) and eight eyes that had 23- or 25-gauge microincision vitrectomy (0.054%) developed acute-onset postoperative endophthalmitis. The between-group difference was statistically insignificant.

Six eyes that had 25-gauge surgery and two eyes that had 23-gauge surgery developed endophthalmitis; the difference was statistically insignificant.

Six of eight eyes that developed endophthalmitis after microincision surgery had final visual acuity of 0.5 or better. There was no reported loss of light perception.

In addition, a meta-analysis of seven studies comprising 77,956 cases showed endophthalmitis rates of 0.03% after 20-gauge vitrectomy and 0.08% after 23- or 25-gauge microincision surgery. The difference was statistically insignificant, the authors reported.

Am J Ophthalmol. 2010; 150(5):716-725

IOP was found to be the main determining factor for progression of exfoliative glaucoma , but a history of severe cardiovascular disease should be investigated as another potential factor, a study suggested.

In the retrospective, multicenter, observational cohort analysis, researchers evaluated 201 patients with exfoliation glaucoma . They found a statistical difference between progressed and non-progressed patients in mean and peak IOP, IOP variance and the number of medicine changes in 1 year.

The patients were from nine academic centers across Europe and had a minimum follow-up of 5 years

In patients with a mean IOP of 22 mm Hg or higher, 84% showed progression. There was a 54% progression rate in those with an IOP between 14 mm Hg and 21 mm Hg and a 33% progression rate in those with an IOP less than 13 mm Hg.

No difference in the rate of progression was observed between groups based on cardiovascular disease history. However, a progression rate of 50% or less was seen in patients with mild or no cardiovascular disease if their IOP was 21 mm Hg or less and in patients with severe cardiovascular disease if their IOP was 18 mm Hg or less.

In addition, 8% of patients with severe cardiovascular disease and an IOP of 20 mm Hg or higher remained stable compared with 38% of patients with mild cardiovascular disease and 21% of patients with no cardiovascular disease history.

Eur J Ophthalmol. 2010; 20:1000-1006.