Correcting IOP Doesn’t Improve POAG Models

Staff
4/5/2012

Analysis of data from the Ocular Hypertension Treatment Study has shown that the calculation of individual risk for developing primary open-angle glaucoma in ocular hypertensive individuals is simpler and equally accurate using intraocular pressure and central corneal thickness as measured, rather than applying an adjustment formula to correct IOP for CCT.

A total of 1,433 of 1,636 participants, randomized to OHTS, with complete baseline data for factors in the prediction model (age, IOP, CCT, vertical cup-to-disc ratio and pattern standard deviation) were reanalyzed using the same prediction model for the development of POAG. In this second analysis, IOP was adjusted for CCT using five different correction formulas. Models were run including and excluding CCT.

C-statistics for prediction models that used IOP adjusted for CCT by various formulas ranged from 0.75 to 0.77, no better than the original prediction model (0.77) that did not adjust IOP for CCT. Baseline IOP, whether adjusted for CCT or not, was statistically significant in all models including those with CCT in the same model. The CCT was statistically significant in all models including those with IOP adjusted for CCT in the same model.

Brandt J, Gordon M, Gao F, Beiser J, et al.


Topical Nepafenac Reduces Postop Pain in Patients
Researchers from India have determined that topical nepafenac is safe, reducing postoperative pain and inflammation in patients undergoing vitreoretinal surgery; its effect on reducing postoperative macular edema and improving visual acuity is equivocal as compared with the standard postvitrectomy therapeutic regime.

One hundred and twenty eyes of 120 patients undergoing vitreoretinal surgery were randomized to receive either topical nepafenac 0.1% (60 eyes) or placebo (60 eyes). Eyes were evaluated for day one postoperative inflammation and two-, four-, six- and eight-week postoperative retinal thickness and best-corrected visual acuity. 

Mean day one inflammation grades of 0.95 ±0.6 and 1.78 ±0.7 were noted in patients taking nepafenac and placebo (p=0.002). The nepafenac and placebo groups had mean central macular subfield thickness of 228.44 ±29.27 μm and 236.21 ±29.44 μm at four weeks (p=0.172) and 205.35 ±25.25 μm and 205.37 ±24.90 μm at eight weeks (p=0.971). At one month, there was no statistically significant difference in the mean visual acuity between the nepafenac group (0.55 ±0.16 decimal units) and the placebo group (0.052 ±0.17 decimal units).

Naithani P, Puranik S, Vashisht N, Khanduja S, et al.


Patients Do Not Report Use of CAM Therapy
Approximately one in nine glaucoma patients use complementary and alternative medicine for their disease, but many do not disclose the use of CAM to their ophthalmologist.

A total of 1,516 patients attending two tertiary glaucoma clinics were surveyed on their use of CAM. The gathered information included demographic variables, ophthalmic history, glaucoma treatment history and details of CAM use. The response rate was 92.5 percent. A total of 166 patients (10.9 percent) reported current use of CAM therapy specifically for glaucoma, whereas 41 patients (2.7 percent) reported past use of CAM. 

Of the patients who reported CAM use, 62.5 percent had not disclosed the use of CAM to their ophthalmologist and 40.5 percent believed that the treatments were helping their glaucoma. The most commonly used types of CAM were herbal medications (34.5 percent), dietary modifications (22.7 percent) and vitamin/mineral supplements (18.8 percent). Of the 207 patients who reported current or past CAM use for their glaucoma, three (1.4 percent) indicated that they used conventional  treatments < prescribed because of their CAM use.

Wan M, Daniel S, Kassan F, Mutti G, et al.


Muscoloskeletal Disorders Among Eye-Care Physicians
Ophthalmologists and optometrists have a higher prevalence of neck, hand/wrist and lower back pain compared to family medicine physicians, according to a survey from the University of Iowa and the Mayo Clinic.

One hundred eighty-six surveys were completed by 94 eye-care physicians and 92 family medicine physicians with a response rate of 99 percent and 80 percent. Eye-care providers, compared with their family medicine colleagues, reported a higher prevalence of neck pain (46 percent versus 21 percent; p=0.01), hand/wrist pain (17 percent versus 7 percent; p=0.03) and lower back pain (26 percent versus 9 percent; p=0.01). A greater proportion of eye-care physicians classified their job as a high-strain job (high demand, low control; 31 percent versus 20 percent). 

Kitzmann A, Fethke N, Baratz K, Zimmerman M, et al.


SCUT Finds Corticosteroids Do Not Improve BSCVA
The Steroids for Corneal Ulcers Trial compared prednisone sodium phosphate 1.0%, to placebo as adjunctive therapy for the treatment of bacterial corneal ulcers and found that use does not improve three-month vision in patients. The primary outcome was best spectacle-corrected visual acuity at three months from enrollment, and secondary outcomes included infiltrate/scar size, reepithelialization and corneal perforation.

Five hundred eligible patients over the four-year study had a culture-positive bacterial corneal ulcer and received topical moxifloxacin for at least 48 hours before randomization. No significant difference was observed in the three-month BSCVA (-0.009 logMAR; p=0.82), infiltrate/scar size (p=0.40), time to reepithelialization (p=0.44) or corneal perforation (p>0.99). A significant effect of corticosteroids was observed, however, in subgroups of baseline BSCVA (p=0.03) and ulcer location (p=0.04). At three months, patients with vision of counting fingers or worse at baseline had 0.17 logMAR better visual acuity with corticosteroids (p=0.03) compared with placebo, and patients with ulcers that were completely central at baseline had 0.20 logMAR better visual acuity with corticosteroids (p=0.02).

Srinivasan M, Mascarenhas J, Rajaraman R, Ravindram M, et al.


Simulated Outcome Results for Toric IOL Surgery
Simulated clinical outcomes suggest that overall results for patients whose toric IOL surgery planning is performed with dual-zone automated keratometry data from the biometer will be equivalent to those for whom manual keratometry is used. 

Patient records at four clinical sites were reviewed, identifying 128 patients who had manual keratometry and biometry with the Lenstar LS 900 recorded before toric IOL implantation and refractive follow-up data after implantation. Preoperative and operative data were extracted from patient charts. Simulated refractive outcomes were calculated based on mathematically removing the actual IOL implanted and then mathematically inserting the IOLs as determined by manual or automated keratometry from the biometry device. Simulated residual refractive astigmatism was lower for the biometer when the standard deviation of the angle of astigmatism was low, and site-to-site variability was also lower.

Hill W, Osher R, Cooke D, Solomon K, et al.