Refractive Outcomes, Contrast Sensitivity, HOAs, and Patient Satisfaction in Moderate Myopia: Wavefront-Optimized Versus Tissue-Saving PRK

PURPOSE

To compare refractive outcomes, contrast sensitivity, higher-order aberrations (HOAs), and patient satisfaction after photorefractive keratectomy for correction of moderate myopia with two methods: tissue saving versus wavefront optimized.

METHODS

In this prospective, comparative study, 152 eyes (80 patients) with moderate myopia with and without astigmatism were randomly divided into two groups: the tissue-saving group (Technolas 217z Zyoptix laser; Bausch & Lomb, Rochester, NY) (76 eyes of 39 patients) or the wavefront-optimized group (WaveLight Allegretto Wave Eye-Q laser; Alcon Laboratories, Inc., Fort Worth, TX) (76 eyes of 41 patients). Preoperative and 3-month postoperative refractive outcomes, contrast sensitivity, HOAs, and patient satisfaction were compared between the two groups.

RESULTS

The mean spherical equivalent was -4.50 ± 1.02 diopters. No statistically significant differences were detected between the groups in terms of uncorrected and corrected distance visual acuity and spherical equivalent preoperatively and 3 months postoperatively. No statistically significant differences were seen in the amount of preoperative to postoperative contrast sensitivity changes between the two groups in photopic and mesopic conditions. HOAs and Q factor increased in both groups postoperatively (P = .001), with the tissue-saving method causing more increases in HOAs (P = .007) and Q factor (P = .039). Patient satisfaction was comparable between both groups.

CONCLUSIONS

Both platforms were effective in correcting moderate myopia with or without astigmatism. No difference in refractive outcome, contrast sensitivity changes, and patient satisfaction between the groups was observed. Postoperatively, the tissue-saving method caused a higher increase in HOAs and Q factor compared to the wavefront-optimized method, which could be due to larger optical zone sizes in the tissue-saving group.

The association of lacrimal gland inflammation with alopecia areata

PURPOSE

To describe the association of lacrimal gland inflammation with alopecia areata.

METHODS

We reviewed the medical records of 4 patients diagnosed with lacrimal gland inflammation who had an antecedent or subsequent episode of alopecia. Data was collected on the presentation age, gender, medical history, disease onset, symptoms and signs, imaging, histopathology, systemic evaluation, management and outcome. Pathology and imaging results were correlated with clinical findings.

RESULTS

Three patients were Asian and one Caucasian. Two developed alopecia after presentation for lacrimal inflammation. The remaining two had a history of alopecia totalis (2 years and 10 years). Three of the 4 patients presented or developed other systemic disorders, including seizures, thrombocytopenia, optic neuritis, ulcerative colitis, allergic rhinitis, lymphadenopathy, vasculitic rash and positive p-ANCA values. All received oral corticosteroids, with the addition of methotrexate therapy in one for relapsing inflammation.

CONCLUSIONS

Lacrimal gland inflammation and alopecia areata are autoimmune processes that can be seen in association with each other.

AAV-mediated and pharmacological induction of Hsp70 expression stimulates survival of retinal ganglion cells following axonal injury

We evaluated the effect of AAV2- and 17-AAG (17-N -allylamino-17-demethoxygeldanamycin)-mediated upregulation of Hsp70 expression on the survival of retinal ganglion cells (RGCs) injured by optic nerve crush (ONC). AAV2-Hsp70 expression in the retina was primarily observed in the ganglion cell layer. Approximately 75% of all transfected cells were RGCs. RGC survival in AAV2-Hsp70 injected animals was increased by an average of 110% 2 weeks after the axonal injury compared to the control. The increase in cell numbers was not even across the retinas with a maximum effect of approximately 306% observed in the inferior quadrant. 17-AAG-mediated expression of Hsp70 has been associated with cell protection in various models of neurodegenerative diseases. We show here that a single intravitreal injection of 17-AAG (0.2 ug/ul) results in an increased survival of ONC injured RGCs by approximately 49% compared to the vehicle-treated animals. Expression of Hsp70 in retinas of 17-AAG-treated animals was upregulated approximately by 2-fold compared to control animals. Our data support the idea that the upregulation of Hsp70 has a beneficial effect on the survival of injured RGCs, and the induction of this protein could be viewed as a potential neuroprotective strategy for optic neuropathies.

Transorbital approach without craniotomy to orbital tumors with extradural intracranial extension

PURPOSE

To review indications and clinical outcomes in a series of orbitocranial tumors treated surgically through a transorbital extradural approach without craniotomy.

METHODS

In this retrospective case series, all patients who underwent surgery through a transorbital extradural approach without craniotomy for benign orbitocranial tumors involving the dura or extending into the anterior or middle cranial fossae were analyzed.

RESULTS

Twenty-seven patients (20 females and 7 males) were included. Median age was 47.0 years (range: 6-74 years) and median follow-up time was 43.5 months (range: 3-148 months). The median preoperative best-corrected visual acuity (logMAR) was improved from 0.35 (range: 0-2.6) to 0.1 (range: 0-2.6) at the last follow-up (p < 0.03). The mean ± SD preoperative exophthalmos significantly decreased from 20.4 ± 3.4 mm to 13.1 ± 3.5 mm at the last follow-up visit (p < 0.01). Four postoperative complications were noted and included one case each of ptosis, numbness, diplopia (transient for 6 months), and cranial nerve VI palsy (transient for 4 months).

CONCLUSIONS

The transorbital extradural approach provides access to the deep orbit and adjacent extradural cranial spaces. Benign orbital tumors that have eroded through the orbital roof, are located in the orbital apex abutting the anterior cavernous sinus and tumors requiring debulking are all processes that can be potentially approached through the transorbital extradural route. Compared to open craniotomy, the incision is smaller, the access more direct and specific risks of open craniotomy are reduced.

Effect of yellow-tinted intraocular lens on standard automated perimetry and short wavelength automated perimetry in patients with glaucoma

Purpose:

To investigate the effect of cataract surgery and yellow-tinted intraocular lens (IOLs) implantation on perimetry indices of short-wavelength automated perimetry (SWAP) and standard automated perimetry (SAP) testing in patients with coexisting cataract and glaucoma.

Materials and Methods:

In this prospective comparative case series, phacoemulsification with implantation of yellow-tinted Acrysof Natural IOL was performed in 16 eyes of 16 patients with visually significant cataract (best-corrected visual acuity (VA) better than 20/120) and mild to moderate glaucoma. Pre- and postoperative values for VA and for perimetry indices including mean deviation (MD), pattern standard deviation (PSD), and foveal threshold (FT) from both SAP and SWAP testing were compared.

Results:

Postoperative VA improved significantly after cataract surgery and yellow-tinted IOL implantation (P < 0.001). After cataract extraction and IOL implantation, MD and FT on SWAP testing improved significantly (P = 0.001); however, there was no statistically significant change with SAP testing between the pre- and postoperative perimetry indices. There was no statistically significant change in PSD with either SAP or SWAP testing postoperatively. The differences between pre- and postoperative values for all perimetry indices under study were not significant when comparing SAP with SWAP tests, except for MD which had improved statistically significantly in SWAP testing (P = 0.03).

Conclusions:

In mild to moderate glaucoma patients with cataracts, the perimetry indices of SWAP testing improved after phacoemulsification and yellow-tinted IOL implantation. This suggests that the yellow-tinted IOLs have less effect on SWAP testing than visually significant cataracts.

Central Corneal Thickness in Highly Myopic Eyes: Inter-device Agreement of Ultrasonic Pachymetry, Pentacam and Orbscan II Before and After Photorefractive Keratectomy

PURPOSE

To determine inter-device agreement for central corneal thickness (CCT) measurement among ultrasound pachymetry, rotating Scheimpflug imaging (Pentacam, Oculus, Wetzlar, Germany), and scanning slit corneal topography (Orbscan II, Bausch & Lomb, Rochester, NY, USA) in highly myopic eyes before and after photorefractive keratectomy (PRK).

METHODS

This prospective comparative study included 61 eyes of 32 patients with high myopia who underwent PRK. Six month postoperative CCT values were compared to preoperative values in 27 patients (51 eyes) who completed the follow up period. To determine the level of agreement, Pentacam and Orbscan II readings were compared to ultrasonic pachymetry measurements as the gold standard method.

RESULTS

Mean CCT measurements with ultrasound, Pentacam, and Orbscan II before PRK were 557µm, 556µm, and 564µm, respectively; and 451µm, 447µm, and 438µm 6 months after surgery in the same order. Preoperatively, the 95% limits of agreement (LoA) with ultrasound measurements were -20μm to 17μm for Pentacam and -21μm to 33μm for Orbscan II. Six months postoperatively, the 95% LoA were -30μm to 23μm for Pentacam and -69μm to 43μm for Orbscan II.

CONCLUSION

Preoperatively, CCT measurements were higher with Orbscan II as compared to ultrasound. Postoperatively, both Pentacam and Orbscan II measurements were lower than those obtained with ultrasound, but Pentacam had better agreement. The use of ultrasound, as the gold standard method, or Pentacam both appear to be preferable over Orbscan II among patients with high myopia.

Macular ganglion cell/inner plexiform layer measurements by spectral domain optical coherence tomography for detection of early glaucoma and comparison to retinal nerve fiber layer measurements

PURPOSE

To evaluate the performance of ganglion cell layer/inner plexiform layer (GCL/IPL) measurements with spectral-domain optical coherence tomography (Cirrus HD-OCT) for detection of early glaucoma and to compare results to retinal nerve fiber layer (RNFL) measurements.

DESIGN

Cross-sectional prospective diagnostic study.

METHODS

We enrolled 99 subjects, including 59 eyes with glaucoma (47 subjects) (mean deviation >-6.0 dB) and 91 normal eyes (52 subjects). Patients underwent biometry and peripapillary and macular OCT imaging. Performance of the GCL/IPL and RNFL algorithms was evaluated with area under receiver operating characteristic curves (AUC), likelihood ratios, and sensitivities/specificities adjusting for covariates. Combination of best parameters was explored.

RESULTS

Average (SD) mean deviation in the glaucoma group was -2.5 (1.9) dB. On multivariate analyses, age (P < 0.001) and axial length (P = 0.03) predicted GC/IPL measurements in normal subjects. No significant correlation was found between average or regional GC/IPL thickness and respective outer retina (OR) thickness measurements (P > 0.05). Average RNFL thickness performed better than average GCL/IPL measurements for detection of glaucoma (AUC = 0.964 vs 0.937; P = 0.04). The best regional measures from each algorithm (inferior quadrant RNFL vs minimum GCL/IPL) had comparable performances (P = 0.78). Entering the GC/IPL to OR ratio into prediction models did not enhance the performance of the GCL/IPL measures. Combining the best parameters from each algorithm improved detection of glaucoma (P = 0.04).

CONCLUSIONS

Regional GCL/IPL measures derived from Cirrus HD-OCT performed as well as regional RNFL outcomes for detection of early glaucoma. Using the GC/IPL to OR ratio did not enhance the performance of GCL/IPL parameters. Combining the best measures from the 2 algorithms improved detection of glaucoma.

Measurement of the optic disc vertical tilt angle with spectral-domain optical coherence tomography and influencing factors

PURPOSE

To report a novel method for measuring the vertical tilt angle of the optic nerve (ON) head and to investigate the associated factors.

DESIGN

Cross-sectional diagnostic study.

METHODS

One hundred and twelve normal, glaucomatous, and glaucoma suspect eyes (99 patients) were enrolled in this study. Subjects underwent a full eye examination, biometry, and spectral-domain optical coherence tomography (SDOCT). The vertical tilt angle was measured on high-resolution cross-sectional SDOCT images passing through the ON head and foveal centers using the inner edges of the Bruch membrane opening as the reference plane. The correlation between the vertical tilt angle with the ovality index and the potential associated factors was estimated with univariate and multivariate linear regression analyses.

RESULTS

The median (interquartile range, [IQR]) axial length and visual field mean deviation were 24.5 (23.8-25.3) mm and -0.9 (-2.76 to 0.26) dB. The median (IQR) tilt angle was 3.5 (1.2-11.2) degrees. There was a moderate correlation between the ovality index and tilt angle (Spearman ρ = 0.351; P < .001). In univariate analyses, axial length, spherical equivalent, and mean deviation were correlated with the tilt angle (P = .002, P = .011, and P = .013, respectively). Axial length, mean deviation, and their interaction showed a statistically significant correlation with the tilt angle in multivariate analyses (P = .044 for axial length, P = .039 for mean deviation, and P = .028 for their interaction).

CONCLUSIONS

We describe a new method for measuring the ON head vertical tilt angle with high-resolution SDOCT imaging. The ovality index demonstrated only a moderate correlation with the tilt angle measurements and hence is not a good proxy measure for the vertical ON head tilt angle. Axial length and visual field mean deviation are the main factors associated with the ON head vertical tilt angle. The underlying basis for the relationship of vertical tilt angle and glaucoma severity should be further explored.

Ocular graft versus host disease following allogeneic stem cell transplantation: a review of current knowledge and recommendations

Graft versus host disease (GVHD) is a common complication of allogeneic stem cell transplantation (allo-SCT). Ocular GVHD develops in approximately 40-60% of patients following allo-SCT and its most common clinical manifestations include keratoconjunctivitis sicca and cicatricial conjunctivitis. Ocular GVHD may lead to severe ocular surface disease, which can significantly diminish quality of life and restrict daily activities. It is thus important to monitor the condition closely since with timely diagnosis, irreversible damage can be avoided. The current review will focus on updated information regarding ocular GVHD.

Dynamic contour tonometry in primary open angle glaucoma and pseudoexfoliation glaucoma: factors associated with intraocular pressure and ocular pulse amplitude

Purpose:

To compare the intraocular pressures (IOP) and ocular pulse amplitudes (OPAs) in patients with primary open-angle glaucoma (POAG) and pseudoexfoliation glaucoma (PXG), and to evaluate ocular and systemic factors associated with the OPA.

Materials and Methods:

In this prospective study, on 28 POAG and 30 PXG patients, IOP was measured with the Goldmann applanation tonometry (GAT) and the Pascal dynamic contour tonometry (DCT). Other measurements included central corneal thickness (CCT), vertical cup-to-disc ratio (CDR), and systolic and diastolic blood pressure. Statistical significance was defined as P < 0.05.

Results:

In each of the POAG and PXG groups, GAT IOP was correlated with CCT (r = 0.40, P = 0.03 and r = 0.35, P = 0.05, respectively), whereas DCT IOP and CCT were not correlated. In all patients and in the POAG group, OPA was positively correlated with DCT IOP (r = 0.39, P = 0.002). OPA was not correlated with CCT in the POAG (P = 0.80), nor in the PXG (P = 0.20) group, after adjusting for DCT IOP. When corrected for DCT IOP and CCT, there was a significant negative correlation between OPA and vertical CDR in all patients (r = −0.41, P = 0.002). There was no significant difference in OPA between groups (P = 0.55), even when OPA was adjusted for IOP and systolic and diastolic pressure (P = 0.40), in a linear regression model.

Conclusion:

DCT IOP and OPA are not correlated with CCT. There is no significant difference between the OPA of PXG and POAG eyes. OPA is correlated with DCT IOP, and is lower in eyes with more advanced glaucomatous cupping.

Long-term outcomes of primary trabeculectomy in diabetic patients with primary open angle glaucoma

AIMS

To evaluate primary trabeculectomy with adjunctive mitomycin-C (MMC) in diabetic patients with primary open angle glaucoma (POAG).

METHODS

Patients with diabetes mellitus (DM) without retinopathy who had ≥6 months of postoperative follow-up were retrospectively compared with a control group selected from the pool of patients without DM matched case-by-case to the diabetic group by age, gender, race, preoperative intraocular pressure (IOP) and lens status. Surgical success was defined as IOP ≤15 and >5 mm Hg (± glaucoma medications) without complications or additional glaucoma surgery.

RESULTS

41 eyes (29 patients) with DM and 81 eyes (64 patients) without DM were compared. Kaplan-Meier cumulative survival rates at 60 months were 57.8±9.3% (DM group) and 68.6±5.3% (control group), and the mean trabeculectomy survival times were 63 months (DM group, 95% CI 50.3 to 75.7) and 74.6 months (control group, 95% CI 67.1 to 82.1; p=0.095). Mean postoperative IOP of control group was statistically significant lower at 2-, 3-, 6- and 7-year follow-up visits (p<0.05). Rates of postoperative complications and additional glaucoma surgeries required were not different between the two groups.

CONCLUSIONS

POAG patients with DM without retinopathy undergoing primary trabeculectomy with MMC do not achieve the same long-term IOP control and may have a lower long-term surgical survival rate compared with patients without DM.

Cataract surgery in eyes with filtered primary angle closure glaucoma

PURPOSE

To evaluate the effect of cataract surgery on intraocular pressure (IOP) in filtered eyes with primary angle closure glaucoma (PACG).

METHODS

In this prospective interventional case series, 37 previously filtered eyes from 37 PACG patients with mean age of 62.1±10.4 years were consecutively enrolled. All patients had visually significant cataracts and phacoemulsification was performed at least 12 months after trabeculectomy. Visual acuity, IOP and the number of glaucoma medications were recorded preoperatively, and 1, 3, 6 and 12 months after surgery. Anterior chamber (AC) depth was measured preoperatively and 3 months after cataract surgery with A-scan ultrasonography. The main outcome measure was IOP at 12 months.

RESULTS

IOP was decreased significantly from 18.16±5.91 mmHg at baseline to 15.37±2.90 mmHg at final follow-up (P<0.01). The mean number of glaucoma medications was significantly decreased from 1.81±0.24 to 0.86±1.00 (P=0.001) at 1 year postoperatively. At final follow up, 36 (97.2%) eyes and 32 (86.4%) eyes had IOP≤21 and IOP≤18 mmHg, respectively; 14 (37.8%) eyes and 9 (24.3%) eyes had IOP≤21 and IOP≤18 mmHg without medications, respectively. The magnitude of IOP reduction was correlated with higher preoperative IOP (r=0.85, P<0.001), shallower preoperative AC depth (r=-0.38, P=0.01) and greater changes in AC depth (r=-0.39, P=0.01).

CONCLUSION

Cataract surgery reduces IOP and the number of glaucoma medications in previously filtered PACG eyes. This reduction seems to be greater in patients with higher preoperative IOP and shallower anterior chambers.

Longitudinal structure-function relationships with scanning laser ophthalmoscopy and standard achromatic perimetry

OBJECTIVE

To explore longitudinal correlations between structural and functional rates of glaucoma progression with confocal scanning laser ophthalmoscopy and standard achromatic perimetry.

METHODS

In this retrospective longitudinal study, 108 eyes with suspected or established glaucoma and 5 or more good-quality scanning laser ophthalmoscopy examinations (global pixel SD<50 μm) and 6 or more reliable visual field (VF) examinations were included. Global and regional rates of progression for VF sensitivity and rim area (RA) were calculated with linear regression analysis. Correlations of global and regional rates of progression were calculated with bivariate correlation analyses. Linear mixed models were built to determine predictive factors for functional and structural changes over time.

RESULTS

The mean (SD) baseline mean deviation was -4.6 (4.9) decibels. The inferotemporal and superotemporal RAs had the highest overall rates of decay (0.0018 mm2/y). Glaucoma progressed in 38 (35.2%) and 20 (18.5%) eyes based on event and trend mean deviation criteria, respectively. The highest correlations of rates were observed between the superonasal or superotemporal RA and inferior VF clusters (ρ=0.25-0.39; P≤.03). Follow-up time, baseline RA, and their interaction were the only significant predictors for RA change; belonging to the group with progression was not associated with higher rates of RA progression.

CONCLUSIONS

Longitudinal structure-function relationships are fair at best in eyes with suspected or established glaucoma. Eyes with progressing disease according to VF criteria do not show significantly higher rates of RA progression. Both structural and functional outcomes need to be monitored to detect glaucoma progression in a timely manner.

Conjunctival limbal autograft and allograft transplantation using fibrin glue

BACKGROUND AND OBJECTIVE

Conjunctival limbal autograft is the surgical treatment of choice for visually significant unilateral limbal stem cell deficiency. The use of fibrin glue, which has been reported extensively in pterygium and other conjunctival surgeries, has not been fully described in limbal stem cell transplantation.

PATIENTS AND METHODS

The authors reviewed 3 cases of conjunctival limbal autograft and 1 of living related conjunctival limbal allograft using only fibrin glue to secure the graft. Main outcome measures included ocular surface stability, visual acuity, and postoperative complications.

RESULTS

At most recent follow-up, all 4 patients (100%) maintained a stable ocular surface. Mean epithelial healing time was 10 days. Mean visual acuity improved from 20/400 to 20/53. All grafts were successful with no postoperative dislocations or displacements.

CONCLUSION

The findings demonstrate that fibrin glue can be used safely and effectively to secure conjunctival limbal grafts in limbal stem cell deficiency. This novel approach has the potential to decrease operative time, increase ease of technique, and improve patient comfort postoperatively.

Retinal nerve fiber thickness is reduced in sleep apnea syndrome

OBJECTIVE

To investigate the prevalence of glaucoma, visual field abnormalities, as well as changes in retinal nerve fiber layer in patients with obstructive sleep apnea syndrome (OSAS).

METHODS

In this cross-sectional study, 51 patients with OSAS were included. Based on apnea hypopnea index (AHI), there were 26, 6 and 19 cases of severe (AHI⩾30), moderate (15⩽AHI<30), and mild (5⩽AHI<15) OSAS, respectively. The control group was matched for age, sex and body mass index. Prevalence of glaucoma and ocular hypertension as well as the following values were assessed and compared between two groups: best-corrected visual acuity, intraocular pressure, central corneal thickness (CCT), cup:disk ratio, mean deviation (MD), pattern standard deviation, and retinal nerve fiber layer (RNFL) parameters using glaucoma diagnosis measurement (GDx).

RESULTS

Seven eyes (6.7%) had intraocular pressure (IOP)>21mmHg; of these, four eyes (3.9%) had glaucoma. No significant difference was detected in CCT between the two groups. IOP was significantly higher in the OSAS group before (p<0.001) and after (p<0.001) correcting for CCT. There was a significant difference between groups in MD and most GDx parameters including DISK (temporal-superior-nasal-inferior-temporal) average (p=0.002), superior average (p=0.05) and nerve fiber indicator (NFI) (p=0.03), where those in the patient group showed lower values. There was a significant positive correlation between AHI and both IOP and NFI.

CONCLUSIONS

OSAS patients had a higher prevalence of glaucoma and ocular hypertension. OSAS patients also had higher IOP, worse visual field indices, and lower RNFL parameters compared with the control group.

Erythropoietin levels in aqueous humor of patients with glaucoma

PURPOSE

To compare the aqueous concentration of erythropoietin (EPO) in eyes with primary open-angle (POAG), pseudoexfoliative (PXFG), and neovascular (NVG) glaucoma with age-matched eyes with cataracts, and to correlate its concentration with other factors including age, gender, intraocular pressure (IOP), type of glaucoma, and severity of glaucoma.

METHODS

In this prospective non-randomized comparative study, a total of 26 eyes with cataracts (control group) and 92 glaucomatous eyes (POAG, 40 eyes; PXFG, 26 eyes; NVG, 26 eyes) were enrolled. Aqueous samples (0.1 to 0.2 ml) were obtained during phacoemulsification, trabeculectomy, phacotrabeculectomy, or Ahmed valve glaucoma implants. The aqueous concentration of EPO was measured using an enzyme-linked immunosorbent assay.

RESULTS

The mean±SEM aqueous level of EPO was statistically significantly higher in eyes with glaucoma (56.7±9.3 mIU/ml) compared to the control group (0.8±0.51 mIU/ml; p<0.001). Eyes with NVG had the highest aqueous level of EPO. Aqueous EPO concentrations remained considerably elevated even in eyes with controlled IOP in all three types of glaucoma. Eyes with PXFG displayed the greatest change in aqueous EPO concentration proportionate to the IOP level. In simple regression analysis, IOP, mean deviation, and the type of glaucoma were the factors that had a statistically significantly positive correlation with the aqueous level of EPO (p=0.011 and <0.001, respectively). Only the type of glaucoma remained statistically significant in the multiple regression analysis (adjusted R(2)=0.278).

CONCLUSIONS

Compared to the control group, the aqueous humor EPO concentration is increased in eyes with POAG, PXFG, and NVG, both with and without controlled IOP. The aqueous level of EPO was more proportionate to the level of IOP in eyes with PXFG compared to eyes with POAG and NVG.

Visual outcome and contrast sensitivity after photorefractive keratectomy in low to moderate myopia: wavefront-optimized versus conventional methods

PURPOSE

To compare visual outcomes and contrast sensitivity after wavefront-optimized or conventional photorefractive keratectomy (PRK) in myopic patients with or without astigmatism.

SETTING

Vanak Eye Surgery Center, Tehran, Iran.

DESIGN

Comparative case series.

METHODS

Patients with low to moderate myopia with or without astigmatism were allocated into 2 groups. The study group was treated with wavefront-optimized PRK (Allegretto Wave Eye-Q software version 2.020 default treatment) and the control group, with conventional PRK (Technolas 217z). In all cases, treatments were bilateral and performed with the same device. Baseline and 3-month postoperative measures were uncorrected and corrected distance visual acuities, manifest refraction, and contrast sensitivity.

RESULTS

Each group comprised 66 eyes. The mean preoperative spherical equivalent refraction improved from -2.99 diopters (D) ± 1.02 (SD) preoperatively to -0.08 ± 0.26 D 3 months postoperatively in the study group and from -2.66 ± 0.95 D to 0.01 ± 0.30 D, respectively, in the control group. In both groups, the postoperative mesopic and photopic contrast sensitivity decreased significantly at most spatial frequencies. The postoperative decrease in contrast sensitivity in both groups was comparable except at spatial frequencies of 3 cycles per degree (cpd) under mesopic conditions and 12 cpd under photopic conditions, frequencies at which the control group had a greater reduction.

CONCLUSIONS

Visual acuity and refractive error outcomes were similar in both treatment groups. After 3 months, mesopic and photopic contrast sensitivity were significantly decreased in both groups; the reduction in the 2 groups was almost comparable.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.