Confident complete excision of lid-margin BCCs using a marginal strip: an alternative to Mohs' surgery.

AIMS: To report a new technique of tissue preparation, using a marginal strip, after the excision of eyelid basal cell carcinomas (BCCs) and to report the long-term results of BCCs excised using this technique. METHOD: After the excision of eyelid BCC with a safety margin of 4 mm, a 1 mm strip was excised along the whole perimeter from the margin of the freshly excised specimen. This marginal strip had intact conjunctival mucosa along one edge and skin along the other. The marginal strip and the central tumour mass were then fixed immediately in formal saline and subjected to conventional histopathology. RESULTS: Of the 61 patients who completed a 5 years follow-up, the results of 28 eye-lid BCCs that were within 4 mm of the lid margin are reported. The marginal strip was clear in 22 specimens and had the presence of residual tumour in its margin in 6 specimens. These six 6 cases were further managed by observation (n = 2), by further surgical excision using marginal strip (n = 2) and by Mohs' surgery (n = 2). CONCLUSION: Marginal strip examines the entire resection margins analogous to Mohs' technique and we recommend its use in lid margin where tarsus is present throughout the specimen and >4 mm from the lid margin.

Impact of retinopathy of prematurity screening examination on cardiorespiratory indices: a comparison of indirect ophthalmoscopy and retcam imaging.

PURPOSE: To compare the impact of retinopathy of prematurity (ROP) screening examination between a digital fundus camera and conventional binocular indirect ophthalmoscopy (BIO) using cardiorespiratory indices as a measure of distress. DESIGN: Prospective comparative (nonrandomized) interventional study. PARTICIPANTS: Eighty-six preterm infants with a birth weight of < or =1500 g or gestational age of < or =32 weeks and undergoing ROP screening were included. METHODS: Retinopathy of prematurity screening examination with BIO or the digital fundus camera was performed. Cardiovascular indices were recorded before, during, and 1 hour after examination. Race, birth weight, gender, twin status, duration of the examination, gestational age, and postconceptual age were recorded. MAIN OUTCOME MEASURES: Heart rate (HR), oxygen saturation, respiratory rate (RR), and mean blood pressure (BP). RESULTS: Thirty-four infants underwent indirect ophthalmoscopy, whereas 52 underwent digital fundus camera examination. The increase in HR and RR was significantly higher in the indirect ophthalmoscopy group than in the digital fundus camera group (P<0.05). There was a significant increase in HR and mean BP during examination in both groups (P<0.05). No clinically significant response persisted at 1 hour. Digital fundus camera examination took significantly longer (P<0.001). CONCLUSIONS: Screening for ROP with a digital fundus camera is associated with a significantly lower stress-related response than conventional indirect ophthalmoscopy.

Single-step transepithelial ASLA (SCHWIND) with mitomycin-C for the correction of high myopia: long term follow-up.

PURPOSE: We wanted to compare the outcomes of single-step modified transepithelial photorefractive keratectomy (tPRK) termed a SCHWIND all surface laser ablation (ASLA) versus conventional alcohol-assisted photorefractive keratectomy (PRK) and laser-assisted in situ keratomileusis (LASIK) for the correction of higher myopia of 6.00 diopters (D) or more, in an area with high risk of haze due to high intensity of sunlight. METHODS: We used a prospective interventional cohort with matched retrospective control groups. Patients with >6 D myopia and <3.5 D of astigmatism were included. All treatments were performed with the SCHWIND Amaris system using aspheric ablation profiles. Mitomycin C was used in all PRK and ASLA cases. Outcomes were postoperative refraction, visual acuity, stability, and complications. The follow-up period was up to 12 months. RESULTS: In total, 101 eyes were included after exclusions. Mean preoperative spherical equivalent refraction was -7.9 D, -8.2 D, and -7.4 D in the ASLA (n=41), PRK (n=29), and LASIK (n=31) groups. Mean postoperative spherical equivalent at 12 months postoperatively was -0.1 (standard deviation [SD]: 0.34), -0.2 (SD: 0.59), and -0.08 (SD: 0.36) in the ASLA, PRK, and LASIK groups, with 91.4%, 85.7%, and 83.9% within 0.5 D of target, respectively. Refractive outcomes and regression at 12 months did not vary among groups (P>0.05). Mean logMAR (logarithm of the minimum angle of resolution) uncorrected distance visual acuity at 12 months was 0.00 (SD: 0.05), 0.06 (SD: 0.1), and 0.05 (SD: 0.09) in the ASLA, PRK, and LASIK groups, with significantly better vision in the tPRK group versus LASIK (P=0.01) and PRK (P=0.01) groups. CONCLUSION: ASLA (SCHWIND) tPRK with mitomycin C for high myopia demonstrates comparable refractive outcomes to LASIK and PRK, with relatively favorable visual acuity outcomes. There was no increased incidence of haze in the ASLA group.

Adjuvant corneal crosslinking to prevent hyperopic LASIK regression.

PURPOSE: To report the long term outcomes, safety, stability, and efficacy in a pilot series of simultaneous hyperopic laser assisted in situ keratomileusis (LASIK) and corneal crosslinking (CXL). METHOD: A small cohort series of five eyes, with clinically suboptimal topography and/or thickness, underwent LASIK surgery with immediate riboflavin application under the flap, followed by UV light irradiation. Postoperative assessment was performed at 1, 3, 6, and 12 months, with late follow up at 4 years, and results were compared with a matched cohort that received LASIK only. RESULTS: The average age of the LASIK-CXL group was 39 years (26-46), and the average spherical equivalent hyperopic refractive error was +3.45 diopters (standard deviation 0.76; range 2.5 to 4.5). All eyes maintained refractive stability over the 4 years. There were no complications related to CXL, and topographic and clinical outcomes were as expected for standard LASIK. CONCLUSION: This limited series suggests that simultaneous LASIK and CXL for hyperopia is safe. Outcomes of the small cohort suggest that this technique may be promising for ameliorating hyperopic regression, presumed to be biomechanical in origin, and may also address ectasia risk.

Transepithelial photorefractive keratectomy with crosslinking for keratoconus.

PURPOSE: To analyse visual, refractive and topographic outcomes of combining transepithelial photorefractive keratectomy (tPRK) with simultaneous corneal crosslinking for the visual rehabilitation of contact lens intolerant keratoconus patients. METHODS: Patients with topographically significant keratoconus, limited corrected vision and intolerant of contact lenses were prospectively recruited, subject to ethical approval and consent. All patients underwent single step aspheric tPRK and sequential crosslinking. Preoperative vision, refraction, corneal topography and wavefront were assessed, with postoperative assessment at 1, 3, 6, and 12 months. RESULTS: 22 eyes of 14 patients were included in the pilot study. Mean age was 32 years (SD 6.8, range 24 to 43). Mean preoperative unaided vision was 1.39 LogMAR (SD 0.5) best corrected 0.31 LogMAR (SD 0.2). Mean preoperative spherical equivalent was -2.74 Diopters (D) (SD 4.1 range -12.25 to +7.75), and mean cylinder -2.9 D (SD 1.2, range 0 to -5.5). Mean central corneal thickness was 461um (SD 29, range 411 to 516). Vision improved postoperatively; unaided 0.32 LogMAR (SD 0.4), best corrected 0.11 (SD 0.13) (P=<0.005). Mean postoperative cylinder was -1.4D (SD1.2), significantly reduced (p<0.005). Maximum keratometry (Kmax) was stable throughout postoperative follow up. (p<0.05). CONCLUSIONS: Non topographic transepithelial PRK with simultaneous crosslinking improves vision, and may offer an alternative to keratoplasty in contact lens intolerant keratoconus. Further comparative studies to topographic PRK techniques are indicated.

Preconditioned donor corneal thickness for microthin endothelial keratoplasty.

PURPOSE: To describe a novel surgical technique to produce thin endothelial grafts for Descemet stripping automated endothelial keratoplasty (DSAEK). METHODS: Thirteen human cadaveric corneas in organ culture were randomized into conventional (n = 7) and microthin (n = 6) DSAEK groups. Grafts in the conventional DSAEK group were prepared using the conventional DSAEK technique of a single microkeratome pass with a 350-µm cutting head. Corneas in the microthin group were preconditioned to achieve a target central thickness of 530 µm before graft dissection with a 350-µm microkeratome head. Preconditioning involved stromal dehydration under pachymetric control using sterile airflow for 15-second increments. Donor and graft thicknesses were assessed with optical coherence tomography, and endothelial viability with trypan blue and alizarin red staining. RESULTS: Mean endothelial graft thickness obtained using the microthin DSAEK technique was 106 µm (SD, 32 µm) compared with 177 µm (SD, 33 µm) obtained using conventional DSAEK technique (P = 0.0024). Donor preconditioning yielded a predicted reduction of 100 µm in graft stromal thickness at a rate of 1.5 µm/s and mean duration of 72 seconds. The average anterior lamella thickness (cut depth) obtained in microthin and conventional DSAEK groups were 424 and 431 µm, respectively (P = 0.84). There was no difference in endothelial viability between the 2 groups. There were no corneal perforations during graft preparation in this study. CONCLUSIONS: Donor preconditioning by pachymetry-controlled stromal dehydration achieved significantly thinner endothelial grafts compared with the conventional DSAEK technique without compromise to endothelial viability or graft wastage.

Clinical and experimental validation of a slit lamp modification to measure toric lens position.

AIM: A simple novel slit lamp beam angular scale modification is described to allow more accurate measurement of toric contact and intraocular lens position. METHODS: The modified slit lamp measuring technique was validated in both an experimental and a clinical setting, with two independent observers. The device was tested against a known reference source, and intraobserver variability in a clinical setting measuring toric intraocular lens (IOL) position was ascertained. RESULTS: In the experimental setting 80 paired observations were analysed. Mean variance was 0.19° (95% CI 0.01-0.37), with a typical measurement error of 0.49°. Intraobserver variation had variance of -0.03° (95% CI -0.2 to 0.15) with a typical error of 0.47°. Clinical assessment of toric IOL position was made in 21 eyes. For this group, intraobserver variation had variance of -0.1° (95% CI -0.281 to 0.62) with a typical error of 1.36°. Intraclass correlation coefficient for all measures was 1.0. CONCLUSION: This simple technique has sufficient precision to be valuable in the clinical setting where photographic techniques may not be available or practical.