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PubMedDate not supplied

Surgical complications caused by inaccurate scotopic preoperative pupillary measurement in cataract and lasik surgery: case report and review of the literature.

Accurate scotopic preoperative pupillary measurements in both cataract and lasik surgery cases are critical to avoid in individuals with naturally briskly dilating pupils under scotopic conditions postoperative visual disability related to low light reflections, disabling illuminance, glare disability, halos, starbursts, and diplopia with night vision. Both edge reflections of the pseudophakos implant in cataract surgery and the ablated corneal margin in lasik surgery can contribute to serious visual disability in patients who have larger scotopic pupils exposing the edge of the implanted lens or the surgical optical zone of the ablated cornea to the entrance pupil. A case is presented in which cataract surgery was performed initially with a 5.5-mm-diameter optic lens in one eye and later a 7.0-mm-diameter optic lens in the other eye. Because of a naturally briskly dilating pupil of 7.0 mm, the eye with the smaller implant experienced significant night vision difficulties because of edge reflections of the exposed implant. The other eye in the very same patient with the larger lens implant was asymptomatic. This case underscores the importance of accurate preoperative pupillary measurements under scotopic conditions to avoid this preventable disabling surgical complication in both cataract and lasik cases.

Cataract Extraction↗
PubMed1998

Effects of fenretinide (4-HPR) on dark adaptation.

OBJECTIVES: To assess the alterations in dark adaptation induced by low (200 mg/d) doses of fenretinide (4-HPR), to assess whether these effects were cumulative and whether they were reversible, and to attempt to elucidate the mechanism underlying the changes in night vision. DESIGN: Case series. SETTING: Outpatient eye clinic. PATIENTS: Twenty-two women enrolled in a breast cancer chemoprevention trial, and 18 normal control subjects. INTERVENTION: Measurements of absolute luminance thresholds during dark adaptation. MAIN OUTCOME MEASURES: Parameters of an exponential model of the dark-adaptation function before, during, and after administration of fenretinide. RESULTS: The most conspicuous effect of fenretinide on dark adaptation was a significant delay in the timing of the rod-cone break (P<.001). A minimal elevation of the final cone threshold was also observed. These effects were reversible after fenretinide therapy was discontinued and did not seem to be cumulative. An inverse relationship between delay of the rod-cone break and plasma retinol concentration was found. CONCLUSION: The dose of fenretinide used in this study produced clearly measurable, but not severe, changes in night vision, which were rarely symptomatic.

Adult↗
PubMedDate not supplied

Early results of nidek customized aspheric transition zones (CATz) in laser in situ keratomileusis.

PURPOSE: Standard ablation profiles for myopia and myopic astigmatism are spherical in shape and usually induce spherical aberration, often resulting in glare, halo, and other night vision problems. New ablation algorithms with aspheric transition zones may help reduce the amount of induced spherical aberrations in refractive surgery. METHODS: Between September and November 2002, 52 eyes were treated with bilateral laser in situ keratomileusis (LASIK) using a new ablation profile with customized aspherical transition zone (CATz). Results were analyzed from examinations performed 1 day, 1 and 3 months (if available) after surgery, and compared to a standard LASIK patient group. RESULTS: Refractive outcome of patients was within +/- 0.50 D of intended correction in 72% on day 1, and 82% at 1 month after surgery. At 1 month after LASIK, mean spherical equivalent refraction was changed from preoperative mean -6.73 +/- 2.04 D to postoperative mean -0.43 +/- 0.80 D (range -2.00 to +1.50 D). No eye lost more than 1 line of visual acuity; 10% gained 1 line and 80% remained unchanged 1 month after surgery. The topographically visible effective optical zone size was larger than in comparable treatments with standard ablation profiles. Spherical aberration was reduced and no patient complained about night vision problems after surgery. CONCLUSIONS: Customized aspheric transition zones may help reduce induction of spherical aberration in refractive surgical correction of myopia and myopic astigmatism.

Adolescent↗
PubMed2002

Mutations in the RPGR gene cause X-linked cone dystrophy.

X-linked cone dystrophy is a type of hereditary retinal degeneration characterized by a progressive dysfunction of the day vision or photopic (cone) system with preservation of night vision or scotopic (rod) function. The disease presents with a triad of photophobia, loss of color vision and reduced central vision. This phenotype is distinct from retinitis pigmentosa (RP) in which there are prominent night and peripheral vision disturbances. X-linked cone dystrophy is a genetically heterogeneous disorder, with linkage to loci on Xp11.4--Xp21.1 (COD1, OMIM 304020) and Xq27 (COD2, OMIM 303800). COD1 maps to a region that harbors the RPGR gene, mutations in which account for >70% of patients with X-linked RP. The majority of these mutations reside in one purine-rich exon, ORF15, encoding 567 amino acids with a repetitive domain rich in glutamic acid residues. We mapped two families with X-linked cone dystrophy to the COD1 locus and identified two distinct mutations in ORF15 in the RPGR gene (ORF15+1343_1344delGG and ORF15+694_708del15) leading to a frame-shift and premature termination of translation in one case and a deletion of five amino acids in another. Consistent with expression of RPGR in rods and cones, our results show that mutations in RPGR, in addition to X-linked RP, can also cause cone-specific degeneration.

Amino Acid Sequence↗
PubMed2000

Functional outcome and satisfaction after photorefractive keratectomy. Part 2: survey of 690 patients.

PURPOSE: To document patient satisfaction and self-perceived quality of vision after bilateral photorefractive keratectomy (PRK). DESIGN: Noncomparative, interventional case series. PARTICIPANTS: Consecutive patients who underwent bilateral PRK from May 1994 through May 1997 by the 12 surgeons of four collaborating centers with a minimum of 4 months since the last surgery and up to 30 months since the first surgery. METHODS: A questionnaire with known psychometric properties was self-administered by the patients. MAIN OUTCOME MEASURES: Responses to individual questions and scale scores. RESULTS: A total of 929 questionnaires were sent, of which 690 were answered and returned (74.3% response rate). The preoperative spherical equivalent ranged from -0.38 diopters [D] to -27.75 D (mean, -5.32 D; standard deviation, 2.85 D). Although 91.8% of the patients were satisfied or very satisfied with their surgery, 96.3% considered that their main goal had been reached, and 95.7% would still choose to have surgery if they had it to do over. The degree of satisfaction was proportional to the postoperative uncorrected visual acuity in the best eye expressed in LogMAR (r = -0.18, P: = 0. 0001) and was negatively correlated with the importance of the corneal haze (r = -0.23, P = 0.0001). Daytime glare was reported to be greater than before surgery by 55.1% of patients. A decrease in night vision was reported by 31.7% of patients, and 31.1% of patients reported increased difficulty driving at night because of their vision. CONCLUSIONS: Overall satisfaction after PRK for low to severe myopia appears to be very good. Glare and night vision disturbance, particularly bothersome for night driving, seem to constitute significant secondary effects that deserve further investigation and should be kept in mind for future improvements in the technique.

Adolescent↗
PubMed2004

Survey of complications and recommendations for management in dissatisfied patients seeking a consultation after refractive surgery.

PURPOSE: To review complications associated with and management options for dissatisfied patients seeking a consultation after refractive surgery performed elsewhere. SETTING: Refractive Eye Surgery Center, The Wilmer Institute, Lutherville, Maryland, USA. METHODS: In this retrospective review, charts of consecutive dissatisfied patients who sought a refractive consultation between June 1999 and January 2003 after refractive surgery performed elsewhere were reviewed and the following parameters were analyzed: visual acuity (uncorrected and best spectacle corrected), prior manifest refraction, complications, and recommendations. The subjective complaints, complications, and visual acuity were reviewed, and the associated historical or visual risk factors as well as treatment options were analyzed. RESULTS: One hundred sixty-one eyes in 101 patients with ocular complaints were identified. One hundred thirty-four eyes (83.2%) had had laser in situ keratomileusis; 22 eyes, photorefractive keratectomy; 4 eyes, radial keratotomy; and 1 eye, laser thermokeratoplasty. The most common subjective complaints were blurred distance vision (59.0%), glare and night-vision disturbances (43.5%), and dry eyes (21.1%). The most common complications were overcorrection (30.4%), irregular astigmatism (29.8%), dry eyes (29.8%), glare (26.1%), difficulty with night driving (16.7%), and corneal haze (16.7%). The most common cause identified in eyes with best spectacle-corrected visual acuity worse than 20/40 was irregular astigmatism (10 of 18 eyes [55.5%]). The most common recommendation for management was medical treatment or observation (68.3%). Medical therapies recommended included lubrication, punctal plugs, topical and systemic pharmaceutical agents to modulate ocular surface, spectacles, and contact lenses. Keratoplasty (lamellar or penetrating) was recommended in 4 patients (4 eyes [2.5%]). The diagnoses included corneal ectasia in 3 eyes and severe flap complication with irregular astigmatism in 1 eye. Nine patients (5.6% eyes) required nonkeratoplasty surgery. In other patients, waiting for advances in technology, including wavefront-guided customized retreatment, was recommended. CONCLUSIONS: A spectrum of complications associated with refractive surgery may result in patient dissatisfaction. Proper patient selection, prevention strategies, and prompt diagnosis and medical or surgical intervention may be beneficial in managing complications and improving patient satisfaction.

Adult↗
PubMed1982

Visual improvements with red-tinted glasses in a patient with cone dystrophy.

A patient with cone dystrophy empirically discovered that his vision improved when a red filter was placed in front of his eyes. The present study documents the conditions under which his visual acuity and field improved and shows that the patient's vision is mediated by the night vision photoreceptors, the rods. Increment threshold functions examined the benefits (and limitations) of red glasses to the patient's vision.

Adult↗
PubMed1999

Polychromatic percepts during hypergravity.

Future helmet mounted systems and cockpit displays will rely on color graphics and information that high performance aircraft pilots will need to discern and understand. Color in displays may help reduce pilot workload. The effect of high G and reduced eye level blood pressure on field-of-view has been study extensively. The effect of high sustained acceleration on color vision, however, is unknown. Research on visual contrast sensitivity, night vision, and visual acuity under acceleration in a human centrifuge has demonstrated changes in vision. We began by having normal color vision subjects view a magnified color aerial map and describe what they saw as we slowly ramped up the G profile from baseline (1.4 G) at 0.1G/sec until they experienced almost complete blackout. At that point subjects began straining and the centrifuge was rapidly decelerated. Several subjects described the river fading away before much else happened. Then the yellow and green features of the terrain faded together. Reds and dark blues appeared to change to black but remained legible until the entire image also faded to black. Computer types call the color of a river on a map cyan. So a display was created that resembled a device know as a "light bar" that is routinely used in centrifuge research. It consisted of a 45 degree wide square projection of green dots in the periphery and a red dot in the center on a white background. Due to our new curiosity about cyan we added dots halfway between the green and red that were cyan. We then ran several people through the same slow onset ramp until near blackout. Several reported that the cyan disappeared completely, significantly before the green. Then the green disappeared, and finally the central red dot. For those who experience it, it is a very useful and repeatable early end point where vision is affected but still available. Next we borrowed a color wheel from the hypobaric chamber and taped it to the wall of the cab. Several subjects reported discomforting angular optical vection due to torsional nystagmus. Thus, a vertical bar arrangement of colors was selected that minimized disruption from involuntary eye movements.

Aerospace Medicine↗
PubMed1991

Early-onset autosomal dominant retinitis pigmentosa with severe hyperopia.

We studied a four-generation family with early-onset autosomal dominant retinitis pigmentosa, severe hyperopia, and axial eye lengths of less than 20 mm. The affected members had decreased vision, night blindness, typical peripheral retinal pigmentary changes, and electroretinographic abnormalities characteristic of retinitis pigmentosa. This pedigree suggests there is another variant of retinitis pigmentosa associated with hyperopia besides Leber's congenital amaurosis and preserved para-arteriole retinal pigment epithelium.

Adolescent↗
PubMed1993

Excimer laser keratectomy for the correction of myopia.

We present the preliminary refractive and visual results in 46 sighted eyes that had undergone excimer photorefractive keratectomy. Although our sample size was small and the follow-up relatively limited (3-6 months), a few important conclusions were drawn. The visual and refractive results compare quite favorably to the preliminary results with radial keratotomy. Thirty-four of 46 patients (74%) were within 1 D of emmetropia; and 45 (98%) were within 2 D at the end of the follow-up period. Forty-four patients (96%) achieved at least 20/40 vision, with more than half achieving 20/20 or better. We encountered no significant vision threatening complications. Twenty of 46 patients (43%) complained of night vision disturbances, but symptoms improved in all patients by 6 months. The majority of patients developed trace epithelial haze; however, corneal haze did not produce reductions in visual acuity. Though the preliminary results of our study of the safety and efficacy of excimer photorefractive keratectomy are promising, further study of long-term vision stability and corneal clarity is clearly needed.

Adult↗
PubMed2006

Connecticut nighttime safety belt use.

PROBLEM: Safety belt use in the United States, as measured over daylight hours, has risen steadily over recent years reaching 80% in 2004. Yet, using the National Highway Traffic Safety Administration's (NHTSA) Fatality Analysis Reporting System (FARS), safety belt use among fatally injured front seat outboard occupants of passenger vehicles was only between 42% and 46% for the years 1999 to 2003. One possible contributing factor is that safety belt use at night, when crash rates are highest, is lower than during the day. METHOD: A full statewide nighttime belt use observation survey was conducted in 2004. This survey was conducted simultaneously with Connecticut's annual full statewide daytime belt use survey. Night belt use observations of drivers and passengers are possible using newly available near military grade night vision goggles and handheld infrared spotlights. Both day and goggle-assisted night observations were conducted at 100 observation sites in Connecticut. Procedures for day and night observations were as nearly identical as possible. RESULTS: The night belt use rate was 6.4 percentage points lower than the day rate (83.0 vs. 76.6). Consistent with belt use among Connecticut fatalities, day versus night differences were greatest in urban areas. There was evidence that day versus night differences were greater before as compared to after a May 2004 belt use enforcement program.

Accidents, Traffic↗
PubMed1998

Glaucoma's impact on quality of life and its relation to clinical indicators. A pilot study.

OBJECTIVE: This study aimed to compare the quality of life (Q of L) of patients with glaucoma and control subjects and to determine the relationships between Q of L and demographic and clinical variables in patients with glaucoma. DESIGN: The study design was a stratified cross-sectional study. PARTICIPANTS: A gender-, race-, and age-stratified cross-sectional sample of patients with glaucoma (n = 56) and control subjects (n = 54) was obtained. Additional patients (n = 12) were included to examine the relationships between glaucoma, its therapy, and Q of L. INTERVENTION: The Medical Outcomes Study short form (MOS-20), the Activities of Daily Vision Scale (ADVS), and questions related to glaucoma and side effects of treatment were administered. Descriptive statistics characterized demographic variables and MOS and ADVS scales. Group differences were evaluated using chi-square, Fisher's and Ordinal Exact, Wilcoxon rank-sum, and two-sample t tests. Spearman rank correlations were obtained between MOS-ADVS scores and clinical and demographic variables. Regression was used for multivariate analysis. MAIN OUTCOME MEASURES: The MOS scores, ADVS scores, visual acuity, visual fields, and demographic variables were measured. RESULTS: Patients scored significantly lower than did the control subjects in all MOS-20 categories except pain. Differences were physical (-20%), role (-43%), mental health (-10%), general health (-22%), and social (-9%). The only category that was not statistically significant was that of pain (P = 0.075). In the glaucoma subgroup, there were differences between whites and nonwhites in MOS subscales physical, role, social, pain, and health, and ADVS near vision. In patients, current medications and previous surgeries correlated with ADVS subscales night vision, near vision, and glare; visual acuity and fields correlated with MOS subscales physical, role and health, and all ADVS subscales. A multiple regression model including visual acuity and fields, urban residence, and female gender explained 61% of the variability in ADVS overall score. CONCLUSIONS: The Q-of-L perception differed between patients with glaucoma and control subjects. Increasing field loss, decreased visual acuity, and complexity of therapy correlated with patients' reduction in activities of daily vision.

Activities of Daily Living↗
PubMed2000

Mutations in NYX, encoding the leucine-rich proteoglycan nyctalopin, cause X-linked complete congenital stationary night blindness.

During development, visual photoreceptors, bipolar cells and other neurons establish connections within the retina enabling the eye to process visual images over approximately 7 log units of illumination. Within the retina, cells that respond to light increment and light decrement are separated into ON- and OFF-pathways. Hereditary diseases are known to disturb these retinal pathways, causing either progressive degeneration or stationary deficits. Congenital stationary night blindness (CSNB) is a group of stable retinal disorders that are characterized by abnormal night vision. Genetic subtypes of CSNB have been defined and different disease actions have been postulated. The molecular bases have been elucidated in several subtypes, providing a better understanding of the disease mechanisms and developmental retinal neurobiology. Here we have studied 22 families with 'complete' X-linked CSNB (CSNB1; MIM 310500; ref. 4) in which affected males have night blindness, some photopic vision loss and a defect of the ON-pathway. We have found 14 different mutations, including 1 founder mutation in 7 families from the United States, in a novel candidate gene, NYX. NYX, which encodes a glycosylphosphatidyl (GPI)-anchored protein called nyctalopin, is a new and unique member of the small leucine-rich proteoglycan (SLRP) family. The role of other SLRP proteins suggests that mutant nyctalopin disrupts developing retinal interconnections involving the ON-bipolar cells, leading to the visual losses seen in patients with complete CSNB.

Adult↗
PubMed2006

Visual function of police officers who have undergone refractive surgery.

INTRODUCTION: The visual acuity and contrast sensitivity of police recruits and officers was evaluated in both normal and dim illumination conditions to determine whether officers who have had refractive surgery have compromised night vision. METHODS: The control group consisted of 76 officers and recruits who have not had refractive surgery and the refractive surgery group consisted of 22 officers and recruits who had refractive surgery. Visual acuity and contrast sensitivity were measured under both room illumination and dim illumination. The room illumination test series included high contrast acuity, low contrast acuity and Pelli-Robson contrast sensitivity. The dim illumination test series included high contrast acuity, low contrast acuity, Pelli-Robson contrast sensitivity, license plate number acuity (with and without glare) and the Mesotest. RESULTS: The general findings were that the refractive surgery group had lower acuity scores on low contrast targets in both room and dim light levels along with a reduction in the Mesotest scores with a glare source compared to the control group. CONCLUSIONS: Although refractive surgery police recruits and officers had reduced performance on some vision tests, these reductions were small and it is unlikely that their performance on vision related tasks would be compromised, on average. The major concern is the small number of refractive surgery candidates whose results were well outside the range of the non-surgical candidates. Their vision may be unacceptable for policing.

Adult↗
PubMed2006

Visual experience and patient satisfaction with wavefront-guided laser in situ keratomileusis.

PURPOSE: To determine the correlation between patient perception and clinical measurements after wavefront-guided laser in situ keratomileusis (LASIK). SETTING: Multicenter clinical trial. METHODS: In this retrospective analysis of clinical study results in 274 eyes, wavefront-guided LASIK procedures were performed in 274 myopic-astigmatic eyes at 6 sites. Comprehensive evaluations of vision and ocular health were conducted preoperatively and for 6 months postoperatively. Visual acuity and contrast sensitivity were measured, and questionnaires were administered. Questionnaire responses were compared with clinical measurements. RESULTS: The overall distribution shifted toward "more satisfied." The "very satisfied" population increased by as much as 70% in all areas. There was no significant change in frequency of visual symptoms. Patients were more expressive about visual decline than visual improvement. Perception of changes in vision appeared to be related to mesopic contrast sensitivity and mesopic contrast sensitivity under glare. Mesopic pupil diameter was not a major predictor of patient satisfaction. Contact lens wearers were more satisfied with postoperative vision than were spectacle wearers. Men were more likely to report visual symptoms and to complain about night vision, although their changes were the same as those of the women. Residual refractive error was a major predictor for most questionnaire items. CONCLUSION: Most patients were as satisfied or more satisfied with their postoperative uncorrected visual acuity than with their preoperative best corrected visual acuity. By continuing to minimize postoperative refractive error through the use of nomograms and improved technology, visual complaints such as night glare and halo could be diminished or even eliminated. The study shows that subjective experience affected satisfaction with results. Some dissatisfaction might be mitigated by being sure patients are educated and have realistic expectations before surgery.

Adult↗
PubMed2006

[Laser ray tracing to measure optical aberrations in eyes with contact lenses].

PURPOSE: To evaluate the impact of disposable soft contact lenses upon visual performance by comparing the optical aberrations of myopic eyes with and without the use of contact lenses. METHOD: The optical aberrations of a set of 18 eyes were measured by a laser ray tracing system, an objective measurement method, enabling comparison of the findings of the naked eye, the eye plus a test lens, and the eye plus a disposable contact lens. RESULTS: There was a large variability among subjects, but the general tendency was that test lenses did not modify aberrations, whereas contact lenses tended to increase the ocular aberrations for large pupils by an average of 40%. There was a lower increase for smaller pupils. CONCLUSION: This study predicts there will be no significant adverse effects on the quality of vision from the use of disposable contact lenses worn under daylight conditions, but a small decline in night vision.

Adult↗
PubMedDate not supplied

Wavefront-guided laser epithelial keratomileusis with the wavelight concept system 500.

PURPOSE: Laser epithelial keratomileusis (LASEK) is a technique of refractive surgery for treatment of myopia. More than 90% of patients are within the intended correction of +/-0.50 diopters (D), without any unwanted side effects. After conventional refractive surgery, higher-order aberrations are induced. To reduce these aberrations, we used wavefront-guided ablation. METHODS: Twenty patients with visual problems in ambient light were included. The primary surgery was 141 to 463 days before the retreatment. LASEK was performed with the Camellin technique with 20% EtOH for 30 seconds. Before surgery, the root mean square (RMS) values were measured and the laser treatment was performed with the WaveLight Concept System 500 (WaveLight Laser Technologie AG). The preoperative spherical equivalent refraction was -1.22 D (SD 0.57 D) and the astigmatism was -0.42 D (SD 0.25 D). Preoperatively and 6 months postoperatively, a comprehensive examination was performed. RESULTS: All retreatments were performed without any intra- or postoperative complications. All patients reported an improvement of vision. The 6-month postoperative refraction was 0.25 D (SD 0.36 D). RMS decreased significantly from 0.72 to 0.47. RMS fourth order also decreased significantly from 0.60 to 0.30 and the spherical aberration decreased significantly from 0.57 to 0.28. CONCLUSIONS: In earlier studies, patients reported reduction of contrast vision, even after resurgery. Our patients showed a significant reduction of higher-order aberrations and better contrast vision after retreatment with wavefront guided LASEK. Retreatment with wavefront-guided LASEK has the potential to correct night vision problems after excimer laser surgery.

Corneal Topography↗
PubMed2000

Melanoma-associated retinopathy versus abnormal retinal function due to interferon-alpha/Isotretinoin therapy in cutaneous malignant melanoma.

PURPOSE: To analyze whether an abnormal retinal function in patients with a cutaneous malignant melanoma was due to paraneoplastic retinopathy or due to isotretinoin or interferon-alpha. METHODS: We studied 15 patients with malignant melanoma in stage IIa and IIb who are all participants in a randomized, multicentered, double-blind placebo-controlled clinical trial comparing interferon-alpha/isotretinoin versus interferon-alpha/placebo performed by the Department of Dermatology, University of Graz. Our assessment included a full ophthalmic history and examination, electrophysiological testing (ERG, EOG), dark adaption, color vision and visual field testing. RESULTS: The most prevalent ocular symptom patients complained about was ocular dryness (8 patients). Electrophysiological as well as psychophysical testings showed no abnormalities in 12 patients. In 1 patient the therapy was stopped because of electrophysiological and psychophysiological pathology. This patient suffered from severe reduction of night vision and visual disturbances. Another patient had had night blindness since childhood which remained stable. CONCLUSIONS: We postulate that in 1 of 15 patients, visual complaints are caused with a high probability by melanoma-associated retinopathy although, in the literature, isotretinoin is described to show similar effects on retinal function.

Aged↗