A group of researchers from Massachusetts has determined that statistical parameters for evaluating the diagnostic performance of the Spectralis spectral-domain optical coherence tomography were good for early perimetric glaucoma and were excellent for moderately advanced perimetric glaucoma.
Participants for this prospective, cross-sectional study were recruited from a university hospital clinic. One eye of 85 normal subjects and 61 glaucoma patients with average visual field mean deviation of -9.61 ±8.76 dB was selected randomly for the study. A subgroup of the glaucoma patients with early visual field defects was calculated separately.
Spectralis SD-OCT circular scans were performed to obtain peripapillary retinal nerve fiber layer thicknesses. The RNFL diagnostic parameters based on the normative database were used alone or in combination for identifying glaucomatous RNFL thinning. The overall RNFL thickness had the highest area under the receiver operating characteristic curve values: 0.952 for all patients and 0.895 for the early glaucoma subgroup. For all patients, the highest sensitivity was achieved by using two criteria: ≥1 RNFL sectors being abnormal at the <5 percent level and overall classification of borderline or outside normal limits, with specificities of 88.9 percent (CI: 95 percent) and 97.1 percent (CI: 95 percent) for these two criteria.
Wu H, de Boer J, Chen T.
Treatment Outcomes in Tube Versus Trabeculectomy Study
Researchers report that five-year treatment outcomes in the Tube Versus Trabeculectomy (TVT) study show that tube shunt surgery has a higher success rate than trabeculectomy with MMC; both procedures were associated with similar intraocular pressure reduction and use of supplemental medical therapy at five years, and additional glaucoma surgery was needed more frequently after trabeculectomy with MMC than after tube shunt placement.
Seventeen clinical centers participated in this randomized clinical trial, with a total of 212 eyes of 212 patients enrolled, including 107 in the tube group (350-mm2 Baerveldt glaucoma implants) and 105 in the trabeculectomy with mitomycin-C group. Patients, between the ages of 18 and 85 years, had previously had trabeculectomy and/or cataract extraction with intraocular lens implantation and uncontrolled glaucoma with IOP ≥18 mmHg and ≤40 mmHg on maximum tolerated therapy.
At five years, IOP (mean ±SD) was 14.4 ±6.9 mmHg in the tube group and 12.6 ±5.9 mmHg in the trabeculectomy group (p=0.12). The cumulative probability of failure during the five years of follow-up was 29.8 percent in the tube group and 46.9 percent in the trabeculectomy group (p=0.002). The rate of reoperation for glaucoma was 9 percent in the tube group and 29 percent in the trabeculectomy group (p=0.025).
Gedde S, Schiffman J, Feuer W, Herndon L, et al.
Upper Lid Blepharoplasty Improves Contrast Sensitivity
Based on patient anecdotes of brighter vision following upper eyelid blepharoplasty, doctors in the United Kingdom have demonstrated a significant increase in contrast sensitivity in patients who have undergone upper eyelid blepharoplasty. This information may be of use in justifying blepharoplasty surgery in the future.
A prospective study looked at pre- and postoperative contrast sensitivity measurements in patients undergoing routine upper eyelid blepharoplasty surgery. The patients were selected for surgery on the basis of a functional visual field effect from dermatochalasis; dermatochalasis is well known to cause visual field defects in many patients. Contrast sensitivity was measured using a Pelli-Robson chart, read at 1 m under standard lighting conditions. This produces a result in log contrast sensitivity. Other data collected included visual acuity and an automated 60:4 visual field. A paired t-test was used to assess the change in contrast sensitivity.
Twenty-eight eyes of 14 patients underwent upper eyelid blepharoplasty surgery. The mean preoperative log contrast sensitivity was 1.49, and the mean postoperative log contrast sensitivity was 1.64. The mean increase in log contrast sensitivity was 0.14 (r: 0-0.45). The increase in log contrast sensitivity was statistically significant (p=0.00002).
Rogers S, Khan-Lim D, Manners R.
Aqueous Humor Variations In Ocular Hypertension Patients
Researchers from the University of Nebraska Medical Center in Omaha, evaluating the interaction of IOP pressure-lowering medications with physiologic day and night changes in aqueous humor dynamics in patients with ocular hypertension, found that latanoprost use significantly decreased IOP during the day and night.
Thirty patients were enrolled in this double-masked, randomized crossover study. Each participant underwent aqueous humor dynamics measurement at baseline and at two weeks of dosing in random order with latanoprost in the evening and placebo in the morning; timolol maleate twice daily; and dorzolamide hydrochloride twice daily. Measurements included central corneal thickness by ultrasound pachymetry, anterior chamber depth by A-scan, seated and habitual IOP by pneumatonometry, blood pressure by sphygmomanometry, episcleral venous pressure by venomanometry and aqueous flow by fluorophotometry. Outflow facility was assessed by fluorophotometry and by tonography. Uveoscleral outflow was mathematically calculated using the Goldmann equation.
Latanoprost increased daytime uveoscleral outflow by a mean (SD) of 0.90 (1.46) μL/min (p=0.048), but a nighttime increase of 0.26 (1.10) μL/min (p=0.47) did not reach statistical significance. Timolol use decreased IOP during the day by reducing aqueous flow by 25 percent. Dorzolamide use lowered IOP only at the noon measurement and reduced daytime aqueous flow by 16 percent. Neither dorzolamide nor timolol use added to the physiologic 47 percent reduction in nighttime aqueous flow.
The daytime IOP-lowering effects of latanoprost are mediated by an increase in uveoscleral outflow, and those of timolol and dorzolamide are mediated by aqueous flow suppression. Nighttime physiologic changes in uveoscleral outflow limit the nighttime pharmacodynamics efficacy of latanoprost. Aqueous flow suppression with timolol and dorzolamide was ineffective in lowering IOP at night.
Gulati V, Fan S, Zhao M, Maslonka M, et al.
Serial Anti-VEGF Injections May Lead to Persistently Elevated IOP
According to researchers in New York City, clinicians should recognize that serial injections of anti-vascular endothelial growth factor agents may lead to elevated IOP that requires glaucoma therapy. This can occur even if the patient has tolerated multiple prior injections without IOP elevation.
Clinical data was reviewed for 25 eyes of 23 patients with neovascular age-related macular degeneration who had increased IOP while receiving interval doses of intravitreal ranibizumab and/or bevacizumab. All eyes had tolerated multiple anti-VEGF injections in the past without IOP elevations.
After a mean of 20 anti-VEGF injections (r: 8 to 40), the mean IOP was 28.9 mmHg (r: 22 to 58 mmHg), compared with a baseline of 16.9 mmHg (r: 14 to 21 mmHg). The mean highest IOP while receiving intravitreal anti-VEGF therapy was 35.8 mmHg (r: 23 to 58 mmHg). Overall, 23 of 25 cases required IOP management. In the remaining two cases, anti-VEGF dosing was switched from regular interval dosing to an optical coherence tomography-guided variable regimen, with subsequent improvement in IOP without anti-glaucoma treatment.
Tseng J, Vance S, Della Torre K, Mendonca L, Cooney M, et al.
PF Tafluprost Well-Tolerated for Ocular Hypertension
In a randomized, double-masked multicenter clinical trial, researchers compared the efficacy and safety of tafluprost, a preservative-free prostaglandin analogue, with PF timolol in patients with open-angle glaucoma or ocular hypertension. The IOP-lowering effect of PF tafluprost was noninferior to that of the PF timolol; PF tafluprost is an efficacious and generally well-tolerated ocular hypotensive agent.
After discontinuation and washout of existing ocular hypotensive treatment, patients who had IOP ≥23 and ≤36 mmHg in at least one eye at the 8:00 hour time point were randomized 1:1 to 12 weeks of treatment with either PF tafluprost 0.0015% or PF timolol 0.5%. IOP was measured three times during the day (8:00, 10:00 and 16:00 hours) at baseline and at weeks two, six and 12. It was hypothesized that PF tafluprost would be noninferior to PF timolol over 12 weeks with regard to change from baseline IOP. The trial was powered for a noninferiority margin of 1.5 mmHg at each of the nine time points assessed.
A total of 643 patients were randomized and 618 completed the study (PF tafluprost=306, PF timolol=312). IOPs at the three time points assessed during the baseline visit ranged from 23.8 to 26.1 mmHg in the PF tafluprost group and 23.5 to 26.0 mmHg in the PF timolol group. IOPs at the three time points assessed during the 12-week visit ranged from 17.4 to 18.6 mmHg for PF tafluprost and 17.9 to 18.5 mmHg for PF timolol. At all nine time points, the upper limits of the two-sided 95 percent confidence intervals for the difference between treatments in IOP lowering were less than the prespecified noninferiority margin. Similar percentages of PF tafluprost and PF timolol patients reported ocular pain/stinging/irritation (4.4 percent vs. 4.6 percent) and pruritus (2.5 percent vs. 1.5 percent). The percentages of PF tafluprost and PF timolol patients reporting conjunctival hyperemia were 4.4 percent vs. 1.2 percent (p=0.016).
Chabi A, Varma R, Tsai J, Lupinacci R, et al.
DLK After LASIK With Femtosecond Laser Flap
According to researchers from the University of Michigan, diffuse laser keratitis after LASIK with femtosecond laser flap creation tended to be mild with little effect on visual acuity. A case-controlled study enrolled 801 eyes (419 patients), with 99 eyes (12.4 percent) of 70 patients developing DLK. Most cases comprised mild flap interface inflammation and were treated with a routine postoperative anti-inflammatory regimen. Twenty-two eyes (2.7 percent) required more than one week of anti-inflammatory treatment.
There was a statistically significant increase in the incidence of DLK with larger flap diameter (p=0.0171), higher side-cut energy (p=0.0037) and higher raster energy (p=0.0033). Patients with DLK were less likely to achieve corrected distance visual acuity of 20/20 or better one day postoperatively (p=0.0453). The difference in acuity was no longer present at one week. There were no significant associations between the incidence of DLK and preoperative refractive error, flap thickness, ablation depth or other treatment parameters.
de Paula F, Khairallah C, Niziol L, Musch D, Shtein R.