Night Vision Symptoms Research Articles

Vitamin A deficiency with nyctalopia after bilateral cataract surgery with multifocal intraocular lenses

Introduction: The purpose of this case study was to report an unusual case of vitamin A deficiency (VAD) with nyctalopia that was diagnosed after bilateral cataract surgery with multifocal intraocular lenses (IOLs). Patient and Clinical Findings: After cataract surgery with multifocal IOLs, a 66-year-old man developed progressive intolerable night vision symptoms, requesting IOL exchange. Diagnosis, Intervention, and Outcomes: Only careful history and investigation revealed the cause to be VAD secondary to celiac disease, rather than lens-related. The patient was commenced on parenteral vitamin A resulting in a complete resolution of nyctalopia. Conclusions: To our knowledge, this is the only reported case of VAD diagnosed in this context. We reflect on the importance of thorough history taking, particularly in patients referred for cataract surgery by their optometrist, where the provided medical history may be incomplete.

Diffractive optic intraocular lens exchange: indications and outcomes.

To assess indications and outcomes of surgical exchange of diffractive optic multifocal and extended depth-of-focus intraocular lenses (IOLs) in favor of monofocal IOLs. Private practice, Los Angeles, California. Retrospective chart review. All cases of diffractive optic IOL exchange between June 2007 and October 2020 for diffractive optic dysphotopsia (DOD) (ie, light-induced concentric circles and spider web patterns), poor visual quality, or night vision symptoms were evaluated retrospectively regarding surgical indications, comorbidities, surgical methods, surgical complications, and visual outcomes. Ocular surface disease and ametropia were managed prior to consideration of IOL exchange. The charts of 64 eyes of 46 patients were included. 53/64 (83%) had DOD, 50/64 (78%) experienced reduced quality of vision, and 12/64 (19%) complained of night vision difficulties. 27/64 (42%) of eyes had no ocular comorbidities; 15/64 (23%) of eyes had more than 1 comorbid condition, and 12/64 (19%) were post-laser refractive surgery. Laser posterior capsulotomy had been performed in 15/64 (23%) of eyes. There were a variety of inciting diffractive optic IOLs and various monofocal exchange lenses and fixation techniques were used based on symptoms, comorbidities, and status of the posterior capsule. After IOL exchange, all eyes were relieved of DOD, and all eyes had improved or unchanged corrected distance visual acuity. Diffractive optic IOLs may induce unsatisfactory visual outcomes. However, in this large series of IOL exchanges, DOD and reduced visual function can be overcome with exchange for a monofocal IOL, despite comorbidities or an open posterior capsule.

Incidence and Outcomes of Optical Zone Enlargement and Recentration After Previous Myopic LASIK by Topography-Guided Custom Ablation.

To report the incidence, visual and refractive outcomes, optical zone enlargement, and recentration using topography-guided CRS-Master TOSCA II software with the MEL 80 excimer laser (Carl Zeiss Meditec AG, Jena, Germany) after primary myopic laser refractive surgery. Retrospective analysis of 73 eyes (40 patients) with complaints of night vision disturbances due to either a decentration or small optical zone following a primary myopic laser refractive surgery procedure using the MEL 80 laser. Multiple ATLAS topography scans were imported into the CRS-Master software for topography-guided ablation planning. The topography-guided re-treatment procedure was performed as either a LASIK flap lift, a new LASIK flap, a side cut only, or photorefractive keratectomy. Axial curvature maps were analyzed using a fixed grid and set of concentric circles superimposed to measure the topographic optical zone diameter and centration. Follow-up was 12 months. The incidence of use in the population of myopic treatments during the study period was 0.79% (73 of 9,249). The optical zone diameter was increased by 11% from a mean of 5.65 to 6.32 mm, with a maximum change of 2 mm in one case. Topographic decentration was reduced by 64% from a mean of 0.58 to 0.21 mm. There was a 44% reduction in spherical aberration, 53% reduction in coma, and 39% reduction in total higher order aberrations. A subjective improvement in night vision symptoms was reported by 93%. Regarding efficacy, 82% of eyes reached 20/20 and 100% reached 20/32 (preoperative CDVA was 20/20 or better in 90%). Regarding safety, no eyes lost two lines of CDVA and 27% gained one line. Regarding predictability, 71% of re-treatments were within ±0.50 diopters. Topography-guided ablation was effective in enlarging the optical zone, recentering the optical zone, and reducing higher order aberrations. Topography-guided custom ablation appears to be an effective method for re-treatment procedures of symptomatic patients after myopic LASIK. [J Refract Surg. 2018;34(2):121-130.].

Simulated night vision after small-incision lenticule extraction

To describe simulated night vision, night-vision symptoms, and refractive outcomes after small-incision lenticule extraction. Tertiary referral eye center, Singapore. Prospective case series. All patients had small-incision lenticule extraction using the Visumax 500kHzfemtosecond laser system. The main outcome measure was simulated night vision logMAR corrected distance visual acuity (CDVA) using the super vision test-night vision goggle vision chart at 12months. Secondary outcomes measures included refractive outcomes (ie, efficacy, predictability, and safety) up to 12months and vision-related symptoms assessed using a validated questionnaire. The study comprised 50 eyes. Overall simulated night vision was not affected (mean CDVA 0.08 logMAR±0.1 [SD], P=.67; mean mesopic CDVA -0.02±0.1 logMAR, P=.58) after small-incision lenticule extraction at the 12-month follow-up. In low myopia, simulated night vision improved from preoperatively (mean 0.099±0.07) to 12months postoperatively (mean 0.006±0.09) (P=.008). Most patients reported mild or no night-vision symptoms 3months after surgery (score range 1.6 to 2.2). At 12months, the overall efficacy index was 0.98±0.20, with 100% of eyes attaining an uncorrected visual acuity of 20/40 or better and 86% attaining 20/20 or better. Ninety-four percent eyes were within ±1.0 diopter of the attempted correction, and the overall safety index was 1.17±0.17. Small-incision lenticule extraction did not affect simulated night vision or contrast sensitivity, with patients reporting no or mild night-vision symptoms. None of the authors has a financial or proprietary interest in any material ormethod mentioned.

Effect of postoperative keratometry on quality of vision in the postoperative period after myopic wavefront-guided laser in situ keratomileusis

To determine whether postoperative keratometry is a predictor of patient-reported satisfaction and night-vision phenomena after wavefront-guided myopic laser in situ keratomileusis (LASIK). Optical Express, Glasgow, United Kingdom. Retrospective case series. Myopic eyes treated with wavefront-guided LASIK were analyzed in this study. All patients completed pre-operative and 1-month postoperative questionnaires, in which the satisfaction with visual outcomes and pre-operative and postoperative night-vision symptoms (glare, halos, starburst, ghosting/double-vision) were rated. Multivariate regression analysis was performed to determine factors associated with questionnaire outcomes. This study evaluated 8672 myopic eyes of 4602 patients. The mean pre-operative manifest spherical equivalent was -3.72 diopters (D) ± 2.00 (SD) (range -0.50 to -11.00 D) and the mean pre-operative keratometry (K) value was 43.64 ± 1.43 D (38.38 to 49.00). At 1 month after surgery, 93.7% and 99.1% of eyes were within 0.50 D and 1.00 D of emmetropia, and 94.6% and 98.3% of eyes achieved monocular and binocular uncorrected-distance visual acuity(UDVA) of 20/20 or better, respectively. There were 48.7% of eyes that had the flat corneal meridian (minimum K) of 40.0 D or less. Although postoperative keratometry was a significant predictor of patient-reported satisfaction and the change in halo reports in the regression analysis, its relative contribution was very low and accounted for less than 0.50% of the variance explained by either model. Postoperative keratometry was not a significant predictor of a change in reports of glare, starburst, and ghosting or double vision. In this large cohort of patients, postoperative keratometry played a minimal and clinically insignificant role in predicting post-LASIK halo visual phenomena and patient-reported satisfaction. Dr. Schallhorn is a consultant to Abbott Medical Optics and Zeiss and a Global Medical Director for Optical Express. None of the other authors have a financial or proprietary interest in the products and materials presented in this paper.

Low luminance deficit and night vision symptoms in intermediate age-related macular degeneration

Background/aimsTo determine the relationship between self-reported visual difficulties under low luminance conditions (night vision symptoms) and visual function measures in intermediate age-related macular degeneration (AMD).MethodsOne hundred participants with bilateral intermediate...

Visual outcome and patient satisfaction after multifocal intraocular lens implantation: Aspheric versus spherical design

To evaluate visual outcomes and patient satisfaction after implantation of an aspheric apodized diffractive intraocular lens (IOL) or a spherical apodized diffractive IOL in cataract surgery. Maastricht University Medical Center, The Netherlands. Nonrandomized clinical trial. This prospective nonrandomized study with a 6-month follow-up compared the results of cataract surgery with implantation of an aspheric AcrySof ReSTOR SN6AD3 IOL and a spherical AcrySof ReSTOR SN60D3 IOL. Main outcome measures were uncorrected (UDVA) and corrected (CDVA) distance visual acuities, uncorrected (UNVA) and distance-corrected (DCNVA) near visual acuities, straylight levels, incidence of glare and halos, and contrast sensitivity levels. The mean UDVA was 0.14 ± 0.15 logMAR in the aspheric group (47 eyes) and 0.14 logMAR ± 0.17 (SD) in the spherical group (45 eyes) and the mean CDVA, -0.01 ± 0.06 logMAR and 0.02 ± 0.10 logMAR, respectively. The mean UNVA was Jaeger (J) 1 in 83.0% of patients in the aspheric group and 55.5% of patients in the spherical IOL group (P = .003). The DCNVA was J1 in 95.7% and 71.1%, respectively (P = .001). There were no significant differences between the 2 groups in contrast sensitivity levels, intraocular straylight levels, incidence of night-vision symptoms, or subjective rating of vision. Patients with the aspheric multifocal IOL had significantly better near vision than patients with the multifocal spherical IOL. The UDVA, CDVA, intraocular straylight, night-vision symptoms, and contrast sensitivity were similar between the 2 groups.

Quality of Life in High Myopia before and after Implantable Collamer Lens Implantation

To examine changes in vision-related quality of life after implantable Collamer lens (ICL) implantation for the correction of myopia. Prospective, interventional, consecutive case series. We included 34 consecutive patients (68% female; mean age, 37 years [range, 23-49]) with preoperative myopia (mean ± standard deviation [SD] refraction spherical equivalent, -11.0 ± 3.12). Bilateral ICL implantation. Quality of life Impact of Refractive Correction (QIRC) score. The median postoperative interval before questionnaire administration was 4 months (range, 3-7). The QIRC scores were significantly higher postoperatively (preoperative QIRC score [mean ± SD], 40.45 ± 4.83; postoperative QIRC score 53.79 ± 5.60; P < 0.001), with significant improvements (P<0.01) for 14 of 19 items. Nineteen (58%) patients reported a worsening in night vision symptoms (mostly nonspecific glare and halo or arc effects) after surgery, but overall levels of satisfaction were high; 88% were either satisfied or very satisfied with the results of surgery. No patients reported overall dissatisfaction. In free text responses, 11 patients (32%) described ICL implantation as life changing or wished that they had opted for the surgery sooner. Implantation of an ICL for myopia is associated with significant improvements in quality of life. Any dissatisfaction with the procedure largely relates to night vision symptoms, which are common in the early postoperative period.

Corneal Wavefront-Guided Retreatments for Significant Night Vision Symptoms after Myopic Laser Refractive Surgery

Corneal Wavefront-Guided Retreatments for Significant Night Vision Symptoms after Myopic Laser Refractive Surgery

Night Vision Symptoms and Progression of Age-related Macular Degeneration in the Complications of Age-related Macular Degeneration Prevention Trial

To describe baseline night vision symptoms and their association with >/=3-lines loss in visual acuity (VA), choroidal neovascularization (CNV), and geographic atrophy (GA). Cohort study within a multicenter randomized clinical trial. A total of 1052 participants with >/=10 large (>125 mu) drusen and VA >/=20/40 in each eye. At baseline, participants self-administered a 10-item Night Vision Questionnaire (NVQ-10). VA testing was performed at baseline, 6 months, and annually. One eye of each participant was randomly assigned to laser treatment, and the contralateral eye was assigned to observation. During follow-up, trained readers identified CNV on the basis of fluorescein angiograms and end point GA, defined as >1 disc area of new GA, based on color photographs. Evaluation was performed by repeated-measures logistic regression for NVQ-10 score as a risk factor for >/=3-lines loss in VA and by survival analysis for CNV and GA, with and without adjustment for participant and ocular characteristics. Evaluations were based on observed eyes and treated eyes, considered separately and combined. A >/=3-lines loss in VA, development of CNV and end point GA. At baseline, NVQ-10 scores ranged from 3 to 100 with a mean of 70 (100 corresponds to no night vision symptoms). Compared with participants with the best night vision (fourth quartile of scores), participants with the worst night vision (first quartile of scores) were at increased risk of >/=3-lines loss in VA in both observed and treated eyes; odds ratios (95% confidence interval) were 2.85 (1.85-4.39) and 2.00 (1.27-3.14), respectively. The relative risk for the first quartile versus the fourth quartile for development of GA was 4.18 (1.80-9.68) in observed eyes and 2.59 (1.13-5.95) in treated eyes. The relative risk for CNV incidence was 1.99 (1.12-3.54) in observed eyes and 1.33 (0.81-2.19) in treated eyes. These relationships were maintained after adjustment for baseline participant and ocular characteristics. Participants who perceived the most problems in their night vision at baseline had an increased risk of >/=3-lines loss in VA, CNV, and GA. These associations are independent of established risk factors.

Efficacy of brimonidine tartrate 0.2% ophthalmic solution in reducing halos after laser in situ keratomileusis

To quantitatively evaluate the effect of brimonidine tartrate 0.2% (Alphagan) on halo and pupil size in patients who had symptomatic night-vision difficulties after laser in situ keratomileusis (LASIK). Nune Eye Hospital, Seoul, Korea. This study comprised 28 eyes of 14 patients with symptomatic night-vision difficulties after LASIK. Pupil diameter was measured with a Colvard pupillometer (Oasis Medical, Inc.). Quantitative analysis of halos was performed by measuring the area using a new computerized method. Pupil size and halo size were evaluated under scotopic and normal room light conditions. Alphagan was administered, and the effect was measured after 30 minutes and 1, 6, 12, and 24 hours. There was a statistically significant correlation between pupil size and halo size (r = 0.527; P<.0001; slope = 691.6 pixel/mm). Pupil size and halo size decreased significantly 30 minutes after Alphagan instillation under both luminance conditions (all P< .0001). Under normal room light, the pupil and halo remained decreased until the last measurement at 24 hours. Under scotopic conditions, the pupil returned to its preinstillation size at 24 hours while the halo remained decreased. The maximum effect on halos was observed after 6 hours, when the mean reduction over preinstillation size was 28.2% and 29.1% under normal room light conditions and scotopic conditions, respectively. Alphagan effectively reduced halo size and pupil size in postoperative LASIK patients with night-vision symptoms.

Corneal Wavefront-Guided Retreatments for Significant Night Vision Symptoms after Myopic Laser Refractive Surgery

To evaluate the results of corneal wavefront (WF)-guided enhancements in patients with night vision symptoms and significantly high positive spherical aberration (SA) after myopic laser refractive surgery. Noncomparative, interventional case series. Twenty-eight eyes of 20 patients with significant night vision symptoms and positive corneal SA (Z(4)(0)) higher than 0.5 microm after myopic laser refractive surgery were included in the study at Vissum-Instituto Oftalmologico de Alicante, Spain. Enhancement surgery was planned to remove residual refractive error and corneal SA (Z(4)(0)) in all cases. All patients underwent corneal WF-guided excimer laser retreatments using the ESIRIS/SCHWIND excimer laser system (Schwind Eye Tech Solutions, Kleinostham, Germany). The main outcome measures were visual symptoms, change in corneal SA (Z(4)(0)), and corneal asphericity (Q-value). Subjective reports of night vision symptoms were improved in all patients. Mean corneal SA (Z(4)(0)) decreased from 0.75 +/- 0.19 microm before surgery to 0.43 +/- 0.42 microm after surgery (P < .001). Mean asphericity in the 4.5-mm zone significantly decreased from 1.02 +/- 1.07 before surgery to 0.52 +/- 0.88 after surgery (P = .008), and the mean asphericity in 8 mm did not change significantly (P = .362). The mean spherical equivalent significantly shifted to hyperopia from -0.22 +/- 1.14 diopters (D) before surgery to 0.33 +/- 0.54 D after surgery (P = .025). Cornea wavefront-guided retreatment was effective in improving subjective night vision symptoms, reducing corneal SA, and decreasing asphericity in eyes that underwent myopic laser refractive surgery.

Corneal Wavefront-guided LASIK Retreatments for Correction of Highly Aberrated Corneas Following Refractive Surgery

To investigate the safety and efficacy of customized corneal wavefront-guided retreatment in symptomatic patients with highly aberrated corneas following LASIK. This prospective study included 75 eyes of 59 patients with significant visual symptoms who underwent LASIK for the correction of residual refractive error. Ablation profiles were calculated using CSO corneal topography and ESIRIS/Schwind laser platform. Eyes were divided into two groups: those with significant night vision symptoms (37 eyes; night symptoms group) and those with decentration, irregular ablation profile, and flap complications (38 eyes; corneal complications group). Corneal topography and aberrations, visual acuity, point spread function (PSF), refractive outcome, and subjective symptoms were evaluated preoperatively, and 1, 3, and 6 months postoperatively. Mean uncorrected visual acuity was 20/32 preoperatively and 20/25 at 6 months postoperatively in the night symptoms group and 20/40 preoperatively and 20/30 at 6 months postoperatively in the corneal complications group. Mean best spectacle-corrected visual acuity was 20/25 both preoperatively and 6 months postoperatively in both groups (t test, P = .219 and P = .149 for the night symptoms and corneal complications groups, respectively). Safety index was 1.1 in both groups, and efficacy index was 0.93 and 0.92, respectively. Statistically significant improvement of total corneal higher order aberrations, tilt, and improvement of spherical aberrations and coma were observed, with corresponding improvement of PSF. Corneal wavefront-guided LASIK retreatment with CSO topography, ORK-W software, and ESIRIS/Schwind laser platform is safe and effective for treating symptomatic patients affected by corneal higher order aberrations or corneal irregularities following LASIK surgery.

Outcomes of LASIK for Myopia With FDA-Approved Lasers

To report expected outcomes of laser in situ keratomileusis (LASIK) for myopia and myopic astigmatism from existing US Food and Drug Administration (FDA) data. Data from Summaries of Safety and Effectiveness for each of the 12 lasers approved by the FDA for LASIK for myopia or myopic astigmatism between 1998 and 2004 were recorded from the FDA Web site. The Cochran-Armitage test for trend was used to determine whether improvements in outcomes occurred with laser technology changes. For all patients, there was a statistically significant trend toward improvement with improved laser technology in the proportion of patients with uncorrected visual acuity (UCVA) of 20/20 or better, UCVA of 20/40 or better, results within +/-0.50 D of intended correction, results within +/-1.00 D of the intended correction, and night vision symptoms (all P < 0.0002). Because there were preoperative differences across laser types, subgroup analyses were also completed. The results for subgroup analyses (high myopia, low to moderate myopia, spherical myopia, and myopic astigmatism) for visual acuity and refractive error outcomes were similar to results for analyses for all groups combined. Conversely, there was no difference across laser types in the proportion of patients who experienced dry eye symptoms or for the proportion of patients with low to moderate myopia who experienced night vision symptoms that were worse or significantly worse than before LASIK. LASIK provides excellent visual acuity and refractive error outcomes. Night vision and dryness symptoms still occur in a significant proportion of patients. Future studies should seek to determine whether additional changes in technology, patient selection criteria, or postoperative treatment could reduce or eliminate these symptoms.

Wavefront-guided Enhancements Using the WaveLight Excimer Laser in Symptomatic Eyes Previously Treated With LASIK

To describe our clinical experience in wavefront-guided LASIK enhancements using the WaveLight ALLEGRETTO system (WaveLight Technologie AG, Erlangen, Germany) for symptomatic eyes previously treated with standard LASIK. Twenty-six eyes of 20 patients with residual myopia, hyperopia, or mixed astigmatism and/or night vision symptoms after primary standard LASIK were considered for wavefront-guided customized retreatment using the WaveLight ALLEGRETTO WAVE 200 Hz excimer laser system (model 106). Preoperative best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity, topography with the ALLEGRETTO Topolyzer, wavefront analysis using the ALLEGRETTO WAVE Tscherning Analyzer, and contrast sensitivity were compared to postoperative (enhancement) measurements. Twenty-two of the original 26 eyes underwent wavefront-guided enhancement, 4 were excluded because they did not meet wavefront-guided treatment inclusion guidelines of this study. Mean follow-up was 8 months (range: 6 to 13 months, standard deviation [SD] 2). All patients were within +/- 0.50 diopters (manifest refraction) of intended postoperative refraction. The mean preoperative BSCVA improved from 20/25 (SD +/- 0.12) to 20/18 (SD +/- 0.1) postoperatively. All patients gained at least one line of BSCVA, and a maximum of three lines. There was no loss of BSCVA in any patient. The total amount of high order aberrations (RMSH) decreased from an average of 1.04 (SD +/- 0.22) to 0.46 (SD +/- 0.14) microm. Patients also had a mean improvement in low contrast sensitivity of 59%. Based on this small series, customized wavefront-guided enhancements using the WaveLight ALLEGRETTO system in patients who underwent previous LASIK appear to be safe and effective in correcting residual refractive error, reducing high order aberrations, and improving visual symptoms when reliable and reproducible measurements are achieved.

Lasik, photokéractectomie réfractive et qualité de vision : étude des facteurs pronostiques et enquête de satisfaction

To confirm the clinical interest of pupillary diameter measurement for selecting indications and determining surgical protocols, to look for clinical factors predisposing to night vision symptoms, and to the assess patient satisfaction level for photoablation techniques not based on aberrometry. This retrospective study was conducted on 111 consecutive myopic patients (219 eyes, with a mean spherical equivalent of -4.25+/-1.84 D); they underwent Lasik (91.3% of cases) or photorefractive keratectomy, after having their pupillary diameter measured by the Colvard pupillometer. Clinical data were collected from medical files, and an anonymous questionnaire was sent in order to assess quality of vision and postoperative satisfaction. Preoperative aims were reached (r=0.41, p<0.0001). The response rate for the questionnaire was 81.1%. Daytime vision was the same or better for 91.1% of the patients, but 25.6% had worse night vision than before. Night vision symptoms were mentioned by 46.7% of the patients, and the most frequent complaint was halos. However, 97.8% of the patients declared themselves as satisfied and would recommend such surgery to their family and friends. A preoperative myopia greater than 4.50D (RR=1.52, p<0.05) and a postoperative keratometry greater than 8.44 mm (RR=1.62, p<0.05) were risk factors for having night vision symptoms, but pupillary diameter was not a risk factor. This survey gives an indirect confirmation of the interest of scotopic pupillary diameter measurement and taking it into account in photoablation protocols. However, night vision symptoms remain frequent but do not influence patient satisfaction. Knowledge of risk factors and technical progress should provide a better quality of vision after Lasik.

Reasons patients recommend laser in situ keratomileusis

To evaluate the reasons patients who have had laser in situ keratomileusis (LASIK) recommend it to others and examine the disparity between high levels of satisfaction and patient reports of night-vision symptoms and/or dry eye after LASIK. Northeastern Eye Institute, Scranton, and the University of Pittsburgh, Pittsburgh, Pennsylvania, and the University of California at Los Angeles, Los Angeles, California, USA. Questionnaires assessing symptoms and satisfaction after LASIK were mailed to 2,100 patients. The questionnaires included items about night-vision symptoms and satisfaction and an open-ended question for patients to give their reasons for recommending LASIK to others. The open-ended responses were categorized and tabulated. Four hundred thirty-four patients provided reasons for recommending LASIK to others. Sixteen categories of reasons were identified. "No more spectacles/contact lenses" was listed by 180 patients (42%), followed by "better vision" (21%) and "convenience" (15%). Women were significantly more likely to cite "better comfort" (27 women versus 3 men; chi square = 8.99, P =.003) and "better quality of life" (41 women versus 9 men; chi square = 7.36, P =.007) as a reason for recommending LASIK. Of the 35 patients who reported dissatisfaction with post-LASIK vision, 20 (57%) would recommend LASIK to a friend because "LASIK helps others." Categories of reasons for recommending LASIK to others were similar to reasons given by patients for seeking LASIK. Some patients who reported dissatisfaction with their vision said they would recommend LASIK, suggesting that recommendation of LASIK to others is not necessarily a measurement of the quality of a patient's vision after LASIK.

Quality of vision and patient satisfaction after LASIK.

The purpose of this article is to review the literature and find characteristics that lead to improved patient satisfaction and better quality of vision. Flatter preoperative corneal curvature is a risk factor for starbursts after laser-assisted in situ keratomileusis (LASIK). Pupil size has not been found to be correlated with night vision symptoms. Wavefront-guided ablations reduce higher-order aberrations in comparison with traditional LASIK. Night vision symptoms are correlated with younger age, greater correction/increased ablation depth, enhancement, and decreased ablation diameter. Contrast sensitivity has been found to initially decrease after LASIK, returning to baseline 6 to 12 months postoperatively. LASIK has quickly become the refractive procedure of choice around the world. Quality of vision and patient satisfaction after LASIK can be difficult to assess because of the many variables that must be considered to accurately measure these endpoints. Preoperative characteristics such as: increased patient age, decreased corneal toricity, or increased pupil size reduce patient satisfaction. Intraoperative factors like decentration, ablation-zone size, active eye tracking, and wavefront guided ablations affect quality of vision. Finally, postoperative factors such as night vision symptoms, reduced contrast sensitivity, and re-treatment can lead to a decline in patient satisfaction. Eliminating or limiting these variables may lead to increased patient satisfaction and higher quality of vision after LASIK.

Patient satisfaction and visual symptoms after laser in situ keratomileusis

Purpose To examine preoperative risk factors for decreased satisfaction and symptoms of glare, halos, and/or starbursts after laser in situ keratomileusis (LASIK). Design Retrospective, case-control study. Participants Participants were 604 previously myopic patients who underwent LASIK at least six months prior to completing the questionnaire. Methods Questionnaires about satisfaction and night vision symptoms were mailed to 2100 patients from the Northeastern Eye Institute, UCLA, and the University of Pittsburgh. Preoperative and postoperative ocular variables were collected from the medical charts of the 841 subjects who returned the questionnaire. Main outcome measures Responses to various satisfaction and night vision symptom questions were compared to demographic and preoperative ocular variables using multivariate logistic regression. Results The questionnaire return rate was 42.9%. The mean age for all subjects was 43.0 ± 10.6 years, and 63% of the subjects were women. Overall, 97% of the subjects would recommend LASIK to a friend. Among subjects who would not recommend LASIK to a friend, a significantly larger percentage reported that they experienced glare, halos, or starbursts (13 of 16 (81.3%) vs. 206 of 388 (53.1%), χ 2 = 4.9, p = 0.03). Also, subjects with flatter preoperative minimum corneal curvature values were more likely to report that they would not recommend LASIK to a friend (OR = 0.71, 95% confidence interval (CI) = (0.52, 0.96), p = 0.03). The median score for satisfaction with vision was 100%, or the maximum value of 127 mm on the visual analog scale. Increasing age was significantly associated with dissatisfaction with vision after LASIK (OR = 1.68, 95% CI = (1.10, 2.56), P = 0.02). Halos were reported by 30%, glare by 27%, and starbursts by 25% of all subjects. Subjects who reported starbursts had a significantly flatter preoperative minimum corneal curvature (43.54 ± 1.60 D versus 43.92 ± 1.69 D, t = 2.15, p = 0.03). Also, subjects who had surgical enhancement were more likely to experience glare, halos, and/or starbursts (OR = 2.14, 95% CI = (1.33, 3.46), p = 0.002). Conclusions Most subjects are satisfied with their vision after LASIK. Our study suggests, however, that certain factors are associated with decreased satisfaction and night vision symptoms after LASIK. Some of these factors include: increasing age, flatter preoperative minimum corneal curvature, and surgical enhancement.

Intacs After Laser in situ Keratomileusis: A Preliminary Report

To assess the corneal topographic and refractive results and feasibility of placing Intacs in eyes with a history of previous laser in situ keratomileusis (LASIK) surgery. This was a prospective study on 25 eyes with residual myopia between -0.75 and -3.00 D. Residual myopia in these patients was secondary to regression or planned undercorrection due to preoperative thin corneas. Main outcome measures included uncorrected visual acuity, preservation of best spectacle-corrected visual acuity, refractive predictability, corneal topographic changes, and evaluation of surgical complications. Initial Intacs procedures after previous LASIK were performed uneventfully. In addition to correcting residual myopia, these procedures may improve night vision symptoms in some patients. These cases may improve our understanding of the ideal corneal shape. [J Refract Surg 2000;1 6(suppl):S236-S238].