Cutaneous Permeation of a Percutaneously Applied Glucocorticoid Using Plant-Based Anionic Phospholipids in Hydrogenated Vegetable Oil: A Preliminary Study.

Purpose: It is important that, when corticosteroids are used therapeutically, concentrations be reduced as much as possible to mitigate potential adverse events and side effects. This preliminary study compares the permeation for the delivery of a corticosteroid in a 1% hydrocortisone-supplemented topical cream containing anionic polar phospholipids (APP) in hydrogenated vegetable oil (triglyceride) versus a market-leading 1% hydrocortisone in a mineral hydrocarbon-based skin cream. Methods: Using the Franz diffusion cell method with cadaveric skin, the permeation of a 1% hydrocortisone-supplemented cream containing APP (test preparation) was compared with a commercially available 1% hydrocortisone cream (control preparation). The principal APP in the test preparation were phosphatidylinositol, phosphatidylserine and phosphatidylglycerol. Permeation was determined at 4 and 8 h time intervals. Results: The permeation values for the 1% hydrocortisone supplemental APP cream (test preparation) were comparatively very high 1180 ng/cm2 at 4 h and 2173 ng/cm2 at 8 h, in contrast to the 1% hydrocortisone cream (control preparation) values of 13 ng/cm2 at 4 h and 98 ng/cm2 at 8 h. Permeation of skin cream increased significantly from 0 to 4 and 8 h, when comparing the APP test preparation with the control preparation (p < 0.001). This translates, respectively, into the 90-fold greater and a 20-fold greater penetration of the test preparation APP cream over the 1% hydrocortisone cream at 4 h and 8 h time points. Conclusions: This preliminary study demonstrates the enhanced permeation of 1% hydrocortisone when applied topically to the skin in an APP skin cream vehicle. This enhanced permeation suggests the potential use of APP technology to deliver therapeutically effective hydrocortisone treatment to the skin at markedly reduced concentrations of steroid. As such, APP technology may offer an improved approach to the treatment of dermatoses associated with inflammatory diseases and conditions requiring prolonged topical corticosteroid therapy.

Corneal absorption of glycerylphosphorylcholine.

This study documents the absorption of glycerylphosphorylcholine (GPC) into corneas ex vivo. Corneas in quadruplicate were incubated in preservation medium containing 30 mM GPC, which is used as a reference marker. The GPC reference marker is used to calibrate 31P nuclear magnetic resonance (NMR) spectral chemical-shift positions for identification of phosphatic metabolites and to calculate intracorneal pH in intact tissues ex vivo. Following baseline NMR ex vivo analysis, corneas were stored in eye bank chambers in preservation medium containing 30 mM GPC at 4 °C overnight for 8 h. After returning to room temperature, NMR analysis was repeated on the same corneas in fresh GPC-free preservation medium. NMR analysis also was performed on the 30 mM GPC preservation medium alone from the eye bank chambers for detection of the GPC signal. The elevated GPC signal unexpectedly persisted in corneas incubated at 4 °C overnight even though GPC was not present in the fresh GPC-free preservation medium. In fact, the concentration of GPC in the intact cornea was many times higher than that found in the cornea endogenously. The levels of phosphatic metabolites and the energy modulus, after subtracting the spectral contribution of the 30 mM exogenous GPC, as well as the intracorneal pH remained unchanged from pre-refrigeration analyses. Corneas also retained transparency through the time-course of this study irrespective of temperature or change in temperature. The GPC signal in the NMR analysis of the preservation medium from the eye bank chambers was nearly undetectable. GPC was unexpectedly absorbed into the corneal tissue without detectable metabolic or physical toxicity. The intracorneal uptake of GPC at reduced temperatures parallels the increase in GPC that occurs naturally in muscle tissue in animals during wintering periods and the very high concentration of GPC in sperm, a cryogenically compatible cell, suggestive of a potential role for GPC in cryopreservation.

Hydrotropic function of ATP in the crystalline lens.

The hypothesis proposed herein is presented to explain the unexpectedly high concentration of ATP and provide evidence to support its hydrotropic function in the crystalline lens determined using 31P NMR. The lens, historically considered to be a metabolically quiescent organ, has the requisite machinery to synthesize ATP, such that the homeostatic level is maintained at about 3 mM. This relatively high concentration of ATP has been found to be consistent among multiple mammalian species including humans. This millimolar quantity is many times greater than the micromolar amounts required for the other known functions of ATP. The recent postulation that ATP at millimolar concentrations functions as a hydrotrope in various cell/tissue homogenates preventing protein aggregation coupled with observations presented herein, provide support for extending the hypothesis that ATP functions as a hydrotrope not only in homogenates but in an intact functioning organ, the crystalline lens. Concentrations of ATP of this magnitude are hypothesized to be required to maintain protein solubility and effectively prevent protein aggregation. This concept is important considering protein aggregation is the etiology for age-related cataractogenesis. ATP is a common ubiquitous intracellular molecule possessing the requisite hydrotropic properties for maintaining intracellular proteins in a fluid, non-aggregated state. It is proposed that the amphiphilic ATP molecule shields the hydrophobic regions on intralenticular fiber cell protein molecules and provides a hydrophilic interfacial surface comprised of the ATP negatively charged triphosphate side chain. Evidence is presented that this side chain is exposed to and has been reported to organize intracellular interstitial water to form an interfacial rheologically dynamic water layer. Such organization of water is substantiated with the effect of deuterium oxide (heavy water) on ATP line widths of the side chain phosphates measured ex vivo by 31P NMR. A novel model is presented to propose how this water layer separates adjacent lens fiber cell proteins, keeping them from aggregating. This hypothesis proposes that ATP can prevent protein aggregation in normal intact lenses, and with declining concentrations can be related to the disease process in age-related cataractogenesis, an affliction that affects every older human being.

Long-Term (3 Year) Effects of a Single Thermal Pulsation System Treatment on Meibomian Gland Function and Dry Eye Symptoms.

PURPOSE: The present study examined the long-term (3 years) effects of a single (12 min) thermal pulsation system (TPS) treatment on symptomatic patients with evaporative dry eye disease (DED) secondary to meibomian gland dysfunction (MGD). METHODS: In this prospective, cohort, observational, single-center study design, signs (meibomian gland secretion [MGS] scores and tear film breakup time [TBUT]) and symptoms (Ocular Surface Disease Index [OSDI] and Standard Patient Evaluation of Eye Dryness [SPEED] questionnaires) were determined in 20 patients (40 eyes) with MGD and dry eye symptoms at baseline (BL), 1 month, and 3 years post-TPS treatment using LipiFlow. RESULTS: Meibomian gland secretion scores increased from BL (4.5±0.8) to 1 month (12.0±1.1, P≤0.001). Improvement persisted at 3 years (18.4±1.4) relative to BL (P≤0.001). Meibomian gland secretion scores in all regions of the lower eyelid were improved over BL at 1 month (nasal [P≤0.001], central [P≤0.001], temporal [P≤0.01]) and 3 years (nasal [P≤0.001], central [P≤0.001], temporal [P≤0.001]). TBUT increased from BL (4.1±0.4) to 1 month (7.9±1.4, P≤0.05) but was not significantly different than BL at 3 years (4.5±0.6, P>0.05). The OSDI scores decreased from BL (26.0±4.6) to 1 month (14.7±4.3, P≤0.001) but returned to BL levels at 3 years (22.5±5.4, P>0.05). The SPEED scores decreased from BL (13.4±1.0) to 1 month (6.5±1.3, P≤0.001), and this improvement persisted at 3 years (9.5±1.6, P≤0.001). CONCLUSIONS: Thermal pulsation may be a uniquely efficacious treatment option for DED secondary to MGD in that a single 12-min procedure is associated with significant improvement in MGS and SPEED scores for up to 3 years.

Long-term (12-month) improvement in meibomian gland function and reduced dry eye symptoms with a single thermal pulsation treatment.

PURPOSE: To determine the 1-year post-treatment dry eye status of subjects with meibomian gland dysfunction and dry eye symptoms after receiving a single LipiFlow Thermal Pulsation System treatment. DESIGN: Single-centre, prospective, observational, open-label, 1-month-registered clinical trial with a 1-year follow-up examination. PARTICIPANTS: Patients with evaporative dry eye disease with meibomian gland dysfunction and dry eye symptoms who had participated in the registered 1-month clinical trial. METHODS: Eighteen of 30 subjects initially enrolled were able to return for a 1-year follow-up. Both eyes of all patients were treated with a single 12-min treatment using the LipiFlow Thermal Pulsation System. Meibomian gland function, tear break-up time and dry eye symptoms were measured. Data are presented for pretreatment (baseline), and 1-month and 1-year post-treatment. MAIN OUTCOME MEASURES: Meibomian gland secretion scores, and tear break-up time and dry eye symptoms. RESULTS: Significant improvement in meibomian gland secretion scores from baseline measurements (4.0 ± 3.4) to 1-month post-treatment (11.3 ± 4.7; P < 0.0005) was maintained at 1-year (7.3 ± 4.6; P < 0.05). Baseline tear break-up time (4.9 ± 3.0) was significantly increased at 1-month (9.5 ± 6.9; P < 0.05); however, this improvement was no longer evident at 1-year post-treatment (6.0 ± 4.4). The significant improvement in symptom scores on Ocular Surface Disease Index and Standard Patient Evaluation of Eye Dryness questionnaires observed at 1-month (P < 0.0005) was maintained at 1-year (Ocular Surface Disease Index [P < 0.05]; Standard Patient Evaluation of Eye Dryness [P < 0.0005]). CONCLUSION: A single 12-min treatment with the Lipi Flow Thermal Pulsation System offers an effective treatment for evaporative dry eye and meibomian gland dysfunction resulting in significant and sustained improvement in signs and symptoms for up to 1 year.

A single LipiFlow® Thermal Pulsation System treatment improves meibomian gland function and reduces dry eye symptoms for 9 months.

PURPOSE: To evaluate the effect of a single treatment with the LipiFlow(®) Thermal Pulsation System on signs of meibomian gland dysfunction (MGD) and dry eye symptoms over a 9-month period. METHODS: Patients (n = 42 eyes, 21 subjects) diagnosed with MGD and dry eye symptoms were recruited for a non-significant risk, prospective, open-label, 1-month clinical trial. Patients received a single 12-minute treatment using the LipiFlow(®) Thermal Pulsation System on each eye. The LipiFlow(®) device applies heat to the conjunctival surfaces of the upper and lower inner eyelids while simultaneously applying pulsatile pressure to the outer eyelid surfaces to express the meibomian glands. Patient symptoms were evaluated using the Ocular Surface Disease Index (OSDI) and Standard Patient Evaluation for Eye Dryness (SPEED) dry eye questionnaires; tear break-up time was measured with the dry eye test (DET™); and meibomian gland function was evaluated using a standardized diagnostic expression technique. Data are presented for patient's pre-treatment (baseline) and at 1-month and 9-month post-treatment. RESULTS: Meibomian gland secretion scores improved significantly from baseline (4.4 ± 4.0) to 1-month post-treatment (11.3 ± 6.2; p < 0.0001) and this improvement was maintained with no significant regression at 9 months (11.7 ± 5.9). Similarly, baseline tear break-up time (4.8 ± 3.2) was significantly increased at 1 month (9.6 ± 7.6; p < 0.001) and this increase was maintained with no significant regression at 9 months (7.1 ± 5.6). Symptom scores on both OSDI and SPEED questionnaires improved significantly at 1 month (p < 0.0001) and this improvement was maintained at 9 months. CONCLUSION: With such prolonged improvement in signs and symptoms of dry eye disease, the LipiFlow(®) Thermal Pulsation System offers a technological advancement for the treatment of dry eye disease secondary to meibomian gland dysfunction. A single 12-minute LipiFlow(®) treatment results in up to 9 months of sustained improvement of meibomian gland function, tear break-up time and dry eye symptoms that are unparalleled with current dry eye treatments.

A new system, the LipiFlow, for the treatment of meibomian gland dysfunction.

PURPOSE: To evaluate the safety and effectiveness of the LipiFlow System compared to the iHeat Warm Compress (WC) for adults with meibomian gland dysfunction (MGD). METHODS: This was a non-significant risk, prospective, open-label, randomized, crossover multicenter clinical trial. One hundred thirty-nine subjects were randomized between LipiFlow (n=69) and WC control (n=70). Subjects in the LipiFlow group received a 12-minute LipiFlow treatment and were reexamined at 1 day, 2 weeks and 4 weeks. Control subjects received a 5-minute iHeat treatment with instructions to perform the same treatment daily for 2 weeks. At 2 weeks, they crossed over (LipiFlow Crossover) and received the LipiFlow treatment. Effectiveness parameters: meibomian gland (MG) assessment, tear break-up time (TBUT) and dry eye symptoms. Safety parameters: adverse events, ocular health exam, ocular surface staining, intraocular pressure, visual acuity and discomfort. RESULTS: LipiFlow resulted in significant improvement (P < 0.05) in MG secretion at 2 and 4 weeks (mean ± standard deviation at baseline = 6.3 ± 3.5; 2 weeks = 14.3 ± 8.7; 4 weeks = 16.7 ± 8.7); and TBUT at 2 and 4 weeks: (at baseline = 5.5 ± 2.9; 2 weeks = 6.9 ± 5.0; 4 weeks = 7.4 ± 5.5). There was no significant change in MG secretion or TBUT in the control group. LipiFlow resulted in a greater significant reduction in dry eye symptoms than the iHeat WC. The crossover group demonstrated similar significant improvement 2 weeks post-treatment with the LipiFlow. There was no significant difference between groups in the incidence of non-serious, device-related adverse events. CONCLUSION: The LipiFlow System was significantly more effective than iHeat WC. These results support its safety and effectiveness in the treatment of MGD and dry eye symptoms.

Inner eyelid surface temperature as a function of warm compress methodology.

PURPOSE: To (1) determine an optimal method of warm compress (WC) application to maximize heating meibomian glands in minimal time, (2) determine the maximum inner eyelid temperature achievable during 30 min of routine WC application, (3) examine the cooling curve for 10 min after WCs have been discontinued. METHODS: Subjects were randomly assigned to one of three WC methodologies. Group A (GrA), (n = 10): 15 min WC application without reheating. GrB, (n = 10): 30 min WC application with reheating every 2 min. GrC, (n = 12): 30 min WC application optimizing contact with the lower lid and reheating every 2 min. WCs were heated to 45 +/- 0.5 degrees C. Outer and inner lower eyelid surface temperatures were measured at baseline and regular intervals. RESULTS: GrA: the maximum outer and inner lower eyelid surface temperatures = 41.2 +/- 0.3 degrees C at 1 min and 38.8 +/- 0.2 degrees C after 4 min, respectively. GrB: the maximum outer upper eyelid temperature, 43.3 +/- 0.5 degrees C, was reached after 6 min while it required 30 min to reach the maximum inner lower eyelid temperature, 40.4 +/- 0.3 degrees C. GrC: it required 4 min to reach the maximum outer lower eyelid temperature, 42.2 +/- 0.4 degrees C, while it required 20 min to reach the maximum inner lower eyelid temperature, 40.8 +/- 0.3 degrees C. CONCLUSIONS: To optimize WC efficiency, patients should (1) heat the WC to approximately 45 degrees C, (2) optimize contact between the WC and outer eyelid surfaces, (3) reheat the WC frequently and have a replacement heated WC on hand for exchange, and (4) perform the activity for at least 4 min in order to achieve an inner lower eyelid temperature > or = 40 degrees C. Longer therapy may be necessary for more severe obstructions. These data suggest that precise, customized, labor-intensive WC procedure is necessary to optimize treating meibomian gland dysfunction and obstruction using WCs.

Warm compress induced visual degradation and Fischer-Schweitzer polygonal reflex.

PURPOSE: To document adverse visual effects of warm compress therapy and determine potential etiologies in subjects with dry eye symptoms. METHODS: Subjects (n = 24) with dry eye symptoms were recruited. Group 1 (n = 13): baseline measurements for each eye included subjective blur, visual acuity (VA), autorefraction (AR), corneal topography (CT), central corneal curvature (CCC), lipid layer thickness (LLT), and evaluation for corneal striae and edema. A warm, moist compress (44.4-45 degrees C) was applied with gentle pressure for 30 min to the closed eyelids of the randomized experimental eye; nothing was applied to the contralateral control eye. Subjective blur, VA, AR, CT, CCC, and LLT were evaluated for each eye at 5, 15, and 30 min and 5 min after application. Striae and edema were assessed for each eye at 30 and 5 min after application. Group 2 (n = 11): the above warm compress protocol was repeated to investigate the Fischer-Schweitzer polygonal reflex at the times stated. RESULTS: At 5 and 30 min, 71% and 88% of all subjects experienced increased subjective blur and decreased VA. At 30 min: Group 1: Of 13 experimental eyes: 13 experienced subjective blur; nine exhibited a VA decrease > or =2 lines (mean = 3.4 +/- 0.7). For the control eye, two subjects reported blur and none exhibited decreased VA. The findings for AR, CT, CCC, LLT, striae and edema did not correlate with blur or with VA decline. Group 2: Of 11 experimental eyes: 10 exhibited the polygonal reflex compared with 0 controls (p < 0.001); eight exhibited subjective blur; seven exhibited VA decrease > or =2 lines (mean = 2.9 +/- 0.9). The polygonal reflex correlated positively to visual blur (r = 0.88, p = 0.04) and to VA decrease (r = 0.79, p = 0.1). CONCLUSIONS: Warm compress application induces transient visual degradation. Although there was no correlation between visual degradation and AR, CT, CCC, LLT, or the presence of striae or corneal edema, visual degradation correlated positively with the polygonal reflex, which was observed following warm compress application.

Increase in tear film lipid layer thickness following treatment with warm compresses in patients with meibomian gland dysfunction.

PURPOSE: Warm-compress therapy applied to the skin of the closed eyelids has been recommended as a treatment for meibomian gland dysfunction (MGD). Previous studies have evaluated the effects of warm-compress therapy on tear-film fluorescein break-up time and tear evaporation rate. The purpose of this study was to determine if tear-film lipid layer thickness (TFLLT) was altered following 5, 15, and 30 minutes of warm, moist compress therapy. METHODS: Twenty patients with a diagnosis of dry eye associated with MGD and a baseline TFLLT of