The medial sural artery perforator flap in intra-oral reconstruction: A Northeast experience.

BACKGROUND: The medial sural artery perforator (MSAP) flap is a fasciocutaneous flap that is gaining popularity for intra-oral reconstructions. The aim of this two-centre review was to evaluate the use of the MSAP flap in intra-oral reconstructions and report our experiences. METHODS: Data were collected prospectively on 35 consecutive intra-oral reconstructions using the free MSAP flap. Patient details and intraoperative flap details were recorded. RESULTS: Thirty-five patients underwent intra-oral reconstruction with a free MSAP flap (26 males and nine females). The average flap dimensions were a length of 8.03 cm, a width of 5.0 cm and a thickness of 7.1 mm. Twenty-two flaps had two perforators, and the average pedicle length was 11.1 cm. There were no flap losses. Ninety-one per cent of donor sites were closed primarily. There were two minor complications related to donor-site wound dehiscence, which required delayed skin grafting. The overall complication rate was 5.7%. CONCLUSIONS: The MSAP flap is a good choice for intra-oral reconstruction. It has reliable anatomy and provides thin, pliable skin with a long pedicle. In addition, donor morbidity is low as the donor site can be closed directly in most cases. It is currently our flap of choice for small intra-oral soft tissue defects.

Experience of Integra(®) in cancer reconstructive surgery.

OBJECTIVES: Integra® has already established its role in acute burn injuries and scar management. It can also be used to cover non-vascularised wounds such as exposed bone resulting from trauma or tumour resection. The aim of this series was to review all cases that underwent Integra® reconstruction following cancer excision. In particular we were interested in the use of Integra for day-case and local anaesthetic procedures in cases where excision was required down to bone or tendon. METHODS: All patients who had Integra reconstruction over a three-year period were prospectively followed. A total of 14 cases were identified for inclusion into the series. In each case patient factors such peripheral vascular disease, age and patient choice meant that traditional methods of reconstruction were not possible. As a result a staged Integra® reconstruction was performed. RESULTS: The 14 cases comprised 11 (78%) males and 3 (22%) females with the majority being diagnosed with Squamous cell carcinomas, 3 (40%) or Malignant Melanomas, 3 (20%). The most common operative sites were digital (5) and scalp (6) in 72% of the cases. The average graft take was 87%. There were 4 early, 4 delayed and 3 late complications in a total of 8 patients mostly resulting in a delay in healing. In 6/14 patients (43%) there were no complications. CONCLUSIONS: Tumour excision and wide local excision may leave patients with defects requiring complex reconstructive surgery. The options available are often compounded by various patient factors. In complex cases we have found the use of Integra® to be a safe and viable alternative to traditional methods of wound closure.

The effect of degree of refractive error on hydrogel contact lens-induced complications and patient self-management behaviors.

INTRODUCTION: Although many aspects of hydrogel lens wear have been explored over the last 20 years, little attention has been paid to the role of refractive error magnitude in determining patients' ocular responses or associated contact lens behaviors. METHODS: A cross-sectional study was conducted in 32 optometric and ophthalmologic practices. We enrolled 2161 spherical soft contact lens-wearing patients. High ametropes were defined as those with at least +/- 5.00 D spherical equivalent refractive error in the right eye. Data on current contact lenses, prescribed care regimens, and slit lamp biomicroscopic signs were provided by the eye care practitioners, and information on actual lens care behaviors and attitudes toward contact lens wear were gathered by survey directly from the patients. All differences between high and low ametropes were compared using the chi-square test. RESULTS: Compared with low ametropes, high ametropes were more satisfied with their vision with contact lenses (p < 0.001). More high ametropes wore their lenses on an extended-wear schedule (p = 0.015). Both groups of patients reported a similar degree of lens awareness and lens-associated pain, but fewer high ametropes reported foreign body sensation (p = 0.002). In managing contact lens discomfort, high ametropes were more likely to use an old spare lens (p = 0.01) and more likely to continue wearing their lenses (p = 0.016)--indicators of a propensity for self-management. In response to a damaged lens, high ametropes were less likely to remove both of their lenses (p = 0.002). High ametropes showed more conjunctival staining (p = 0.001) and more corneal scars (p = 0.033). High ametropes also presented with more corneal fluorescein staining (p = 0.001) and more corneal vascularization (p < 0.001). These relations between the degree of ametropia and slit lamp signs of contact lens wear were not significantly affected by daily- vs. extended-wear status. CONCLUSIONS: In summary, practitioners should consider the implications of the patient's degree of ametropia when prescribing contact lenses. These results indicate the need for closer observation and specific advice concerning management of contact lens-related problems when caring for patients with high refractive errors.

Characterization of ocular surface symptoms from optometric practices in North America.

PURPOSE: This study characterized ocular symptoms typical of dry eye in an unselected optometric clinical population in the United States and Canada. METHODS: Self-administered dry eye questionnaires, one for non-contact lens wearers (dry eye questionnaire) and one for contact lens wearers (contact lens dry eye questionnaire), were completed at six clinical sites in North America. Both questionnaires included categoric scales to measure the prevalence, frequency, diurnal severity, and intrusiveness of nine ocular surface symptoms. The questionnaires also asked how much these ocular symptoms affected daily activities and contained questions about computer use, medications, and allergies. The examining doctors, who were masked to questionnaire responses, recorded a nondirected dry eye diagnosis for each patient, based on their own diagnostic criteria. RESULTS: The dry eye questionnaires were completed by 1,054 patients. The most common ocular symptom was discomfort, with 64% of non--contact lens wearers and 79% of contact lens wearers reporting the symptom at least infrequently. There was a diurnal increase in the intensity of many symptoms, with symptoms such as discomfort, dryness, and visual changes reported to be more intense in the evening. The 22% percent of non-contact lens wearers and 15% of contact lens wearers diagnosed with dry eye (most in the mild to moderate categories) reported symptoms at a greater frequency than those not diagnosed with dry eye. CONCLUSIONS: Our results show that symptoms of ocular irritation and visual disturbances were relatively common in this unselected clinical population. The intensity of many ocular symptoms increased late in the day, which suggested that environmental factors played a role in the etiology of the symptoms.

Recovery from hyperemia after overnight wear of low and high transmissibility hydrogel lenses.

PURPOSE: To measure the limbal vascular response after 8 hours of eye closure while wearing high and low permeability lenses compared to control eyes without lenses. METHOD: Twenty neophyte participants wore lotrafilcon A silicone hydrogel lenses (HDk; Dk = 140) or etafilcon A hydrogel lenses (LDk; Dk = 18). On two different nights the lenses were randomly worn for 8 hours during sleep in the right eyes only. Left eyes were non-lens wearing controls. Biomicroscopic images of the temporal limbal area were videotaped at baseline, on eye opening and every 20 minutes for 3 hours. A masked observer graded digitized images of the limbal area. RESULTS: On waking and after lens removal there were no differences in hyperemia between the HDk and LDk lens wearing eyes. There were also no differences at any time between the HDk lens wearing eyes and their control eyes (p > 0.05). On waking the eyes wearing the LDk lens were more hyperemic compared to baseline (p < 0.001) and compared to their control eyes at 20 (p < 0.001) and 180 minutes (p = 0.01), indicating slower recovery from hyperemia. The HDk lens wearing eyes recovered to their baseline levels by 180 minutes (p = 0.99), compared to the LDk lens wearing eyes, which had not recovered to baseline levels by 180 minutes (p = 0.04). CONCLUSION: The reduction in hyperemia over time of the HDk lens wearing eyes was the same as the controls. The LDk lens wearing eyes were more hyperemic than the controls on waking and the reduction in hyperemia over time was slower. This suggests that the slower recovery from hyperemia may be affected by the lower oxygen transmissibility of the LDk lens.

Vascular response to extended wear of hydrogel lenses with high and low oxygen permeability.

PURPOSE: The purpose of this study was to determine the impact of extended wear of high and low oxygen permeability (Dk) lenses on the development or resolution of limbal hyperemia and corneal neovascularization in a randomized prospective clinical trial. METHODS: Adapted daily-wear contact lens wearers were randomly assigned to one of two groups. The low-Dk group (N = 23) wore etafilcon A lenses (Dk/t = 40) for up to 7 days and 6 nights, and the high-Dk group (N = 39) wore lotrafilcon A lenses (Dk/t = 175) for up to 30 days and nights. Limbal hyperemia and neovascularization were assessed and graded during 9 months of extended wear. A stratified analysis to determine how change in ocular redness depended on initial presentation was also conducted. RESULTS: On a 0 to 100 scale, extended wear of low-Dk lenses resulted in a 16-point increase in limbal hyperemia (p < 0.0001); no significant change occurred with the high-Dk lenses. The difference was greatest for low-Dk participants who initially presented with lower levels of hyperemia (N = 18). There was a slight resolution of redness in participants who initially presented with higher levels of hyperemia (N = 10) after wearing the high-Dk lenses. Neovascularization increased by an average of 0.5 on a scale of 0 to 4 in low-Dk lens wearers (p < 0.0001) but remained unchanged in the high-Dk lens wearers. The increase was most marked for the low-Dk group with lower levels of neovascularization at baseline. CONCLUSIONS: Subjects who wore lenses with higher oxygen permeability for 9 months of extended wear exhibited a lower vascular response of the ocular surface compared with subjects who wore lenses of lower oxygen permeability for the same period. This result was found both for the surface limbal vessels and in the deeper neovascular stromal vessels. Moderate neovascularization also developed after 3 months of extended wear of low-Dk hydrogels, whereas high-Dk lenses caused no neovascularization.

Changes in myopic refractive error with nine months' extended wear of hydrogel lenses with high and low oxygen permeability.

BACKGROUND: A small but significant increase in myopia after extended wear of low oxygen permeability (Dk) hydrogel lenses has been previously reported; however, the specific impact of hypoxia on refractive status and corneal curvature with extended wear are not well documented. The purpose of this study was to compare the refractive changes induced over a period of 9 months' extended wear with high-Dk fluorosiloxane hydrogel lenses and low-Dk hydrogel lenses. METHODS: Adapted daily wear contact lens wearers were randomly assigned to one of two groups. The low-Dk group wore etafilcon A (Dk = 28) for up to 7 days and 6 nights and the high-Dk group wore lotrafilcon A (Dk = 140) for up to 30 days and nights. Refractive error and corneal curvature were measured at 3-month intervals over 9 months of extended wear. RESULTS: The etafilcon A group demonstrated an average increase in myopia of 0.30 D over the 9-month period; however, no change in spherical myopic correction was measured in the lotrafilcon A group. The cylindrical component did not change in either group. A stratified analysis revealed a greater increase in myopia for low myopes than moderate myopes in the etafilcon A group but no difference in the lotrafilcon A group. Keratometric analysis revealed no change in the etafilcon A group and a small degree of central corneal flattening in both major meridians of 0.35 D in the lotrafilcon A group. CONCLUSIONS: Nine months of extended wear of low-Dk lenses is associated with a small degree of myopic progression in adult myopes that appears to be reversible. Wearing fluorosiloxane-hydrogel lenses of high-Dk had no impact on refractive error and may be associated with a small degree of central corneal flattening.

Sympathetic swelling response of the control eye to soft lenses in the other eye.

PURPOSE: To compare central corneal swelling and light scatter after 8 hours of sleep in eyes wearing high- and low-Dk hydrogel lenses and to the contralateral control eyes. METHODS: Twenty neophyte subjects wore a Lotrafilcon A (Dk, 140; Ciba Vision, Duluth GA) silicone hydrogel lens and an Etafilcon A (Dk, 18; Acuvue; Vistakon, Jacksonville, FL) 58% water content hydrogel lens of similar center thickness in random order in the right eye only, for overnight 8-hour periods. The contralateral nonwearing left eyes served as controls. Central corneal thickness was measured using an optical pachometer and light scatter using a Van den Berg stray-light meter before lens insertion, after lens removal on waking, and every 20 minutes for the next 3 hours. RESULTS: Central corneal swelling induced by the Etafilcon A lens on eye opening was significantly higher than with the Lotrafilcon A lens (8.66%+/-2.84% versus 2.71%+/-1.91%; P<0.00001). Light scatter induced by the Etafilcon A lens on eye opening was significantly higher than with the Lotrafilcon A lens (46.09+/-5.62 versus 42.78+/-6.07 Van den Berg units, P = 0.0078). The swelling of the control eyes paired with the Etafilcon A lens-wearing eyes was also slightly but significantly higher than that of the control eyes paired with the Lotrafilcon A lens-wearing eyes (2.34%+/-1.26% versus 1.44%+/-0.91%; P = 0.0002). Light-scatter measurements were not significantly different between control sets of eyes but showed the same trend. CONCLUSIONS: In neophyte subjects, corneal swelling of the contralateral control eyes appears to be influenced by the swelling of the fellow lens-wearing eyes-that is, the swelling of the contralateral control eye was significantly lower when there was less swelling of the fellow eye wearing the high-Dk lens. Although there was no statistically significant difference in light-scatter measurements between the control sets of eyes, a trend similar to the corneal swelling results was observed, which could be used to support the suggestion that this may be a sympathetic physiological response rather than an unusual sampling coincidence.

Characteristics of corneal staining in hydrogel contact lens wearers.

Corneal fluorescein staining is widely used in clinical practice and research, but little information exists on the distribution of staining in a large group of asymptomatic contact lens wearers. This cross-sectional study took place at 3 centers, and investigated the pattern of corneal fluorescein staining in both eyes of 98 hydrogel contact lens wearers. We also investigated the strategies used by three experienced clinicians to grade corneal staining. Overall corneal staining was graded using a scale from 0 to 4 in one-half steps, and five corneal zones, superior, inferior, nasal, temporal, and central, were also graded. The average overall staining grade for both eyes of our subjects was 0.50, with an average of 0.57 for the right eye and 0.44 for the left. This difference between the eyes was statistically significant (p = 0.011). In addition, a comparison of the zones within each eye showed a significant difference (p = 0.0001) among the zones. Corneal staining between the two eyes was also positively and significantly correlated (r = 0.58; p = 0.0001). Grading strategies among clinical investigators were significantly different (p = 0.0001), indicating a potential source of bias in multi-centered studies. The difference in corneal staining between the eyes may represent a source of systematic bias, and could be due to grading the right eye before the left. The correlation in corneal staining between the eyes indicates that the two eyes of a subject cannot serve as independent data points. One-third of the subjects who participated in this study had notable corneal staining. This finding underlines the importance of regularly checking corneal staining in clinical practice.

The clinical presentation, prevalence, and risk factors of focal corneal infiltrates in soft contact lens wearers.

PURPOSE: We evaluated the clinical presentation, prevalence, and associated risk factors for focal corneal infiltrates with overlying fluorescein staining in a population of soft contact lens wearers. METHODS: We measured the prevalence of focal stromal infiltrates with overlying fluorescein staining among contact lens wearers in a large cross-sectional, masked, multicenter study. RESULTS: The practice-based occurrence of infiltrates with overlying staining was 1.6%, or 38 of 2,324 patients examined. The events were milder than those reported in studies conducted in specialty eye care centers; were usually noted during unscheduled office visits; and were accompanied by symptoms of redness, photophobia, pain, and foreign body sensation. The infiltrates were located in all corneal zones, with 44.7% of the infiltrates involving the central zone, none of which caused significant loss of acuity at follow-up. The risk factors of overnight wear, lens modality (e.g., conventional, disposable), and smoking have been confirmed. Overnight wear showed a prevalence ratio of 1.88 compared with daily wear (P < 0.055, chi-square); lens modality showed an increased risk for disposables compared with conventional lenses of 2.1 (P = 0.036, chi-square). Smoking was associated with an increased prevalence of events; 1.2% of "never" and 2.2% and 2.4% of "former" and "current" smokers, respectively, experienced an infiltrate, for a prevalence ratio of 2.0 (P < 0.04). Smoking and lens modality also interacted positively with extended wear, amplifying the risk associated with those factors. CONCLUSIONS: We found a 1.6% practice-based prevalence and a wide range of clinical presentation of focal infiltrates in soft contact lens wearers, and we measured the relative risks of extended wear, lens modality, and smoking in a general practice population. In these cases, there was no distinct pattern in location or severity of corneal infiltrates, and visual acuity following the events was not compromised.

Effect of storage time with different lens care systems on in-office hydrogel trial lens disinfection efficacy: a multi-center study.

A combined prospective and retrospective study was conducted to evaluate the efficacy of in-office disinfection methods for hydrogel trial contact lenses. Two hundred and twenty-one trial contact lenses, disinfected by four different disinfection methods, were collected from seven Study Centers and cultured for microbial contamination after various storage periods. Negative and positive control lenses were included as an additional Center in this double-masked study. There was a significant difference in the incidence of microbial contamination among the Centers for all storage times (chi 2 p < 0.001). Contamination of trial lenses in Centers using thermal disinfection with preserved saline (SoftWear Saline) was negative and thermal disinfection with nonpreserved saline (LensPlus Saline) was 8.7%. Lens contamination in Centers using chemical disinfection was 13.6% with ReNu and 40.7% with OptiFree. The degree of contamination ranged from 90 colony forming units (CFU)/ml to over 10 million CFU/ml. Among the microorganisms isolated after the different disinfection methods were Alcaligenes xylosoxidans, Serratia marcescens, Moraxella phenylpyruvica, Enterobacter agglomerans, Pseudomonas stutzeri, and various gram-positive organisms. This study suggests that practitioners should redisinfect all inventory trial lenses at least once a month to minimize the risk of patient infection.

Effect of H2O2 concentration and exposure time on stromal swelling: an epithelial perfusion model.

The corneal epithelium can be affected adversely by some preservatives used in contact lens solutions. To test the effect of H2O2 at the epithelial surface, the rabbit cornea was perfused with various concentrations of H2O2, and the effect on stromal and Anterior Bright Band (ABB) thickness measured for 150 min. The study compares stromal swelling and ABB swelling for a single 10-min pulse with that for a 150-min sustained dose. With the 10-min pulse dose there was no significant swelling up to 235 ppm H2O2, the highest dose tested. With the sustained dose, significant stromal swelling began between 72 and 153 ppm H2O2. These results indicate that residual H2O2 present at the epithelial surface after neutralization in current contact lens disinfection systems does not have a high enough concentration to affect corneal function adversely.

Hydrogen peroxide in anterior segment physiology: a literature review.

The role of hydrogen peroxide when it is physiologically produced or when it is applied externally to the eye is examined in this review. Three enzymes deal with the endogenously produced H2O2. They are catalase, superoxide dismutase, and glutathione peroxidase. These enzymes are present at different concentrations in ocular tissues and function most efficiently at different concentrations of H2O2. For H2O2 which contacts the external surface of the eye, the same enzymes also seem to act to metabolize the H2O2. In general the eye is more sensitive to changes in pH than to low concentrations of topically applied H2O2 at concentrations less than about 400 ppm. So, the small amounts of residual H2O2 which remain on contact lenses after disinfection in H2O2 solutions do not pose a great risk to the eyes.