Effect of Scleral Contact Lens Size and Duration of Wear on Intraocular Pressure.

OBJECTIVE: To evaluate the effects of scleral lens size and the duration of wear on intraocular pressure (IOP) during lens wear. METHODS: Healthy adults were recruited for this prospective and randomized study. Intraocular pressure measurements were performed using a pneumotonometer. A block randomization was used to assign the order of scleral lens diameter of either 15.6 mm or 18.0 mm for 5-hr bilateral wear over a course of two visits. Scleral IOP (sIOP) was measured during the predetermined intervals, 1.25 hr apart, during the 5-hr scleral lens wear. Corneal IOP (cIOP) was measured before and after the scleral lens wear. The primary outcome measure was the mean change in sIOP from prelens insertion baseline. RESULTS: Corneal IOP unchanged after scleral lens removal compared with the baseline measurements ( P =0.878). Smaller and larger lenses introduced significantly higher sIOP at 2.5 hr after lens insertion with the mean (95% CI) increase of 1.16 (0.54, 1.78) mm Hg and 1.37 (0.76, 1.99) mm Hg, respectively. There was no difference in IOP change between the smaller and larger diameter lenses ( P =0.590). CONCLUSIONS: Well-fitted scleral lenses do not result in clinically significant changes in intraocular pressure during 5-hr lens wear in young and healthy individuals.

Corneal Health during Three Months of Scleral Lens Wear.

SIGNIFICANCE: This study evaluated the effects scleral lens wear has on corneal health using fluorometry and in vivo confocal microscopy. No subclinical changes on healthy corneas of young subjects were observed during 3 months of scleral lens wear. PURPOSE: This study aimed to evaluate the effects 3 months of scleral lens wear has on the corneal epithelial barrier function, dendritic cell density, and nerve fiber morphology. METHODS: Twenty-seven neophytes (mean [standard deviation] age, 21.4 [3.9] years) wore scleral lenses of a fluorosilicone acrylate material bilaterally (97 Dk, 15.6 to 16.0-mm diameter) for 3 months without overnight wear. Subjects were randomized to use either Addipak (n = 12) or PuriLens Plus (n = 15) during lens insertion. Measurements of corneal epithelial permeability to fluorescein were performed with automated scanning fluorophotometer (Fluorotron Master; Ocumetrics, Mountain View, CA) on the central cornea of the right eye and the temporal corneal periphery of the left eye. Images of the distributions of corneal nerve fibers and dendritic cells and nerve fibers were captured in vivo with a confocal laser scanning microscope (Heidelberg Retina Tomograph, Rostock Cornea Module; Heidelberg Engineering, Heidelberg, Germany) on the central and inferior peripheral cornea of the left eye. Corneal measurements and imaging were performed at baseline and after 1 and 3 months of lens wear. RESULTS: The corneal permeability values in natural log, dendritic cell densities, and nerve fiber morphology did not significantly change from baseline to 1 and 3 months of lens wear, for both central and peripheral corneal regions (P > .05). Dendritic cell density at the inferior cornea was higher than the central cornea throughout the study (P < .001). No relationships were observed between each outcome measurements and the saline solution groups (P > .05). CONCLUSIONS: Scleral lens wear for 3 months on healthy cornea of young subjects did not affect corneal epithelial barrier function, nerve fiber, and dendritic cell densities. Buffered and nonbuffered saline solutions impacted the corneal health in similar ways.

Not All Dry Eye in Contact Lens Wear Is Contact Lens-Induced.

OBJECTIVES: To compare subjective and clinical outcomes in three study groups: (1) asymptomatic contact lens (CL) wearers (ASYM); (2) symptomatic CL wearers who become asymptomatic on lens removal; and (3) symptomatic CL wearers who do not resolve on lens removal. METHODS: Ninety-two subjects completed the Berkeley Dry Eye Flow Chart with and without lenses, ocular surface examinations, and a battery of questionnaires. RESULTS: Thirty-seven subjects (40%) were ASYM, 30 (33%) had contact lens-induced dry eye (CLIDE), and 25 (27%) had underlying physiological DE. Visual Analog Scale ratings, OSDI score, and SPEED score were significantly better for the ASYM group (P<0.001) but did not distinguish CLIDE from DE. The DE group was significantly worse than CLIDE and ASYM, which were similar, in precorneal noninvasive tear breakup time (8.2 sec DE vs. 12.3 sec CLIDE and 14.3 sec ASYM; P=0.002), anterior displacement of the Line of Marx (P=0.017), and superior conjunctival staining (P=0.001). CONCLUSIONS: Many CL wearers presenting with dryness symptoms have an underlying DE condition and will not respond to treatments aimed at changing lenses or solutions. Contradictory results from research studies of DE in CL wearers could be due in part to a failure to distinguish subjects with symptoms due specifically to CL wear from those whose symptoms have underlying causes unrelated to CL wear.

Effects of scleral-lens oxygen transmissibility on corneal thickness: A pilot study.

PURPOSE: To investigate the effect of various oxygen transmissibilities (Dk/t) of scleral lenses and corneal thickness recovery time from overnight eye closure with patching on corneal edema during 5 h lens wear. METHODS: Scleral lenses (hofocon A, 15.6 mm diameter) were worn bilaterally with three different Dks (100, 140, and 160 Barrer). Central and peripheral corneal thickness (CCT and PCT) were measured using optical coherence tomography. Four subjects were randomly selected for one additional visit and asked to patch one eye before night sleeping. The patch was not removed until lens insertion to avoid corneal deswelling. Then CCT of both eyes was measured. RESULTS: Ten neophytes with healthy eyes participated in the study. Mean [95% CI] Dk/t of the study lenses was 32.0 [29.2, 34.7] hBarrer/cm. Mean [95% CI] CCT immediately upon lens insertion and after 5 h of lens wear were 532.4 [520.3, 544.5] µm and 538.7 [526.5, 551.0] µm, respectively. Mean [95% CI] percentage change (%Δ) in CCT was 1.2% [0.9%, 1.5%], 1.2% [0.9%, 1.4%], and 0.8% [0.6%, 1.1%] for CCT, nasal PCT, and temporal PCT, respectively. There was an inverse relationship between temporal Dk/t and %ΔPCT (p < 0.05) while Dk/t was not found significantly associated with either CCT or nasal PCT. The patched eyes maintained a relatively stable CCT and showed progressive deswelling, starting and ending with 2.8% and 0.6%, respectively. In contrast, the unpatched eyes swelled, starting with nearly 0% and ending with 0.7% with a maximum swelling of 1.8%. CONCLUSION: There was limited amount of corneal edema induced by short-term scleral lens wear with lens Dk/t ranging from 21 to 47 hBarrer/cm and lenses with lower lens Dk/t did not induce significantly higher corneal swelling. Scleral lens insertion soon after overnight eye closure with patching did not introduce additional swelling for young and healthy eyes.

Tear dynamics under scleral lenses.

PURPOSE: To evaluate post-lens tear dynamics at two different time points during scleral lens wear in two cohorts with 10 neophytes each. METHODS: All subjects wore bilaterally scleral lenses for 5 h on 3 separate visits. Post-lens tear exchange was measured using Out-in method, which required 5 µL of 2% FITC-Dextran instilled on the bulbar conjunctiva during lens wear. Time taken to observe the first sign of fluorescence in post-lens tear reservoir was recorded with a stopwatch. Out-in measurements were collected at 5-hour post-lens insertion in Group 1 and compared with those obtained at 20 min of lens wear in Group 2. Tear dynamics under the lens was observed in Group 2 with fluorogram using a modified slit-lamp technique (Tan et al., 2018) to monitor post-lens fluorescence intensity and with high-resolution spectral domain optical coherence tomography (ENVISU 2300; Bioptigen Inc.) to measure post-lens tear thickness (PoLTT) over 5 h of lens wear. RESULTS: 60% of subjects in Group 1 achieved Out-in times less than 5 min at 5-hour post-lens insertion, compared with 67% of subjects at 20-min lens wear (Tan et al., 2018). Using qualitative analysis on 60 series of data in Group 2 to compare the changes in fluorescence intensity and PoLTT with respect to lens-wearing time, 27% was due to lens settling, 13% was due to tear exchange and mixing while 60% indicated tear dynamics under scleral lenses was due to a combination of tear exchange, mixing, and lens settling. CONCLUSION: Tear flow into tear reservoir under a scleral lens on subjects with healthy cornea occurred at 20 min and 5 h after lens insertion. After 5 h of lens wear, roughly one third of the subjects had no tear flow into post-lens reservoir, as the observed decline in post-lens tear fluorescence was predominately due to lens settling.

A preclinical and clinical review of aflibercept for the management of cancer.

Aflibercept, also known as vascular endothelial growth factor (VEGF)-Trap, is a recombinant, decoy receptor fusion protein, rationally designed to block angiogenesis by targeting not only all forms of VEGF-A, but also VEGF-B and placental growth factor. It inhibits VEGF-induced angiogenesis in preclinical models. In tumor models, aflibercept is associated with the reduction of tumor vasculature and size, and the inhibition of ascites formation. Clinical studies are investigating the use of aflibercept alone and in combination with other antineoplastic therapies for the treatment of various cancers. Phase I and II studies have provided proof of principle, and support the continuing clinical investigation of aflibercept. Results from the phase III study, VITAL, of aflibercept in the second-line setting in patients with advanced non-small cell lung cancer [NCT00532155] demonstrated efficacy in progression-free survival and overall objective response rate, but overall survival was not significantly improved. A full report awaits publication. The Phase III VANILLA trial in metastatic pancreatic cancer [NCT00574275] showed no improvement in overall survival. Most recently, the phase III VELOUR study [NCT00561470] of aflibercept plus FOLFIRI compared with placebo plus FOLFIRI in patients with metastatic colorectal cancer following failure of an oxaliplatin regimen showed significant improvements in overall survival, progression-free survival, and response rate and the complete results have been submitted to a peer-reviewed journal. This review summarizes preclinical and clinical data for aflibercept and discusses future directions and clinical trials for this agent.