bluuebunny/crossref_metadata_2025 huggingface dataset:
The Accommodative Convergence/Accommodation (AC/A) and Near Convergence/Distance (NC/D) Ratios in Esotropia
Authors: Filipovic Tatjana
Published: April 2021

ABSTRACT

Introduction: In esotropías, measurement of AC/A and NC/D ratios are Important for exact classification and adequate therapy. We devised a table for the calculation of AC/A and NC/D ratios to facilitate their estimation.

Method: For the assessment of AC/A ratio, we used the grathent method range 6 Dsph and for the NC/D ratio we used the heterophoria method. For the calculation of both ratios, we used our own table. A series of 102 children were examined.

Results: The mean value of AC/A ratio for esotropías was 4.86±2.05. The mean value of AC/A ratio for the control group was 3.9±1.92.The difference was 0.96 and was statistically significant at the level of 5% (Student's / test). The AC/A ratio is high in esotropia ranging from 1 to 1 0. At 58% of esotropías, the AC/A ratio is higher than the mean value of AC/A ratio of the control group.

The mean value of the NC/D ratio for esotropía was 5.9±1 .51 . The mean value of the NC/D ratio for the control group was 5.1 ±1.5. The difference of 0.8 was statistically significant at a level of 5%. Thus, in esotropia the NC/D ratio is high.

The NC/D ratio in esotropia ranges from I to 10. The NC/D ratio is low in 16% of esotropías.

Conclusion: Our own table for calculating the AC/A and NC/D ratios was useful because it facilitates their determination. The mean values of AC/A and NC/D ratios in esotropia are high and range from 1 to 10. In 58% of cases the AC/A ratio Is high and in 84% of cases the NC/D ratio Is high and can be responsible for the oculomotor imbalance.
Lenz Syndrome in Two Sisters: Clinicopathologic Correlations of the Ocular Anomalies
Authors: Krishnamurthy Mina S , Urban Robert C , Kousseff Boris G , Margo Curtis E
Published: April 2021

ABSTRACT

Background: The Lenz syndrome (Mendelian Inheritance in Man catalog number 309800) is a presumed X-linked recessive disorder. Major diagnostic criteria include ocular, skeletal, and urogenital manifestations. We describe two sisters and the two sons of one of them with Lenz syndrome. The eye from one boy was removed because of pain and total loss of vision, allowing histopathologic documentation of the ocular malformations.

Methods: Clinicopathologic case report.

Results: Two sisters in this family displayed several of the major diagnostic criteria of the Lenz syndrome. The stunted growth of the eye, and the ocular and non-ocular anomalies defines the microphthatmos as monogenie, complex, and colobomatous.

Conclusion: The pattern of inheritance of Lenz syndrome is best explained by X-linked dominant transmission. Future reports of familial cases with an excess of affected females are needed to confirm this hypothesis.
Long-term Results of Trabeculectomy for Congenital Glaucoma
Authors: Dureau Pascal , Dollfus Hélène , Cassegrain Christine , Dufier Jean-Louis
Published: April 2021

ABSTRACT

Background: To evaluate long-term results of intraocular pressure after trabeculectomy for congenital glaucoma.

Methods: Data concerning 55 eyes (30 patients) who underwent trabeculectomy for congenital glaucoma were recorded. Mean age at diagnosis was 3.4 months (range: 2 days to 10 months). Mean follow up was 56.8 months. Associated anterior segment abnormalities, need for one or more new trabeculectomy procedures during follow up, and intraocular pressure at the last examination were noted.

Results: Of the 55 eyes, 48 met the success criteria (87.3%). A second and sometimes third or fourth trabeculectomy were necessary during follow up in 17 eyes (31%). Of the seven failures at final examination, six (85%) had been diagnosed and operated on before the age of 1 month, whereas 15 of the 48 eyes with good results (31.2%) were in this group (p<.02). Of the seven failures at final examination, six (85%) were operated on two to four times, whereas 10 of the 48 eyes with good results (20.1%) were in this group (p<0.01). An associated anterior segment abnormality was present in 13 eyes (23%), and did not seem to influence the final outcome.

Conclusion: Trabeculectomy is an effective procedure for long-term control of intraocular pressure in congenital glaucoma. The early diagnosis and surgical treatment correspond to a poor long-term prognosis, probably related to initially severe cases. In these cases, intraocular pressure is difficult to control despite repeated surgical procedures.
Laser Interferometric Prediction of Postoperative Visual Acuity in Patients With Genetic Ectopia Lentis
Authors: Guo Xiangming , Chen Youzhao , Guo Li , Jia Xiaoyun
Published: April 2021

ABSTRACT

Purpose: To compare preoperative laser interference visual acuity (LIVA) with postoperative Snellen visual acuity (SVA), and to evaluate clinical significance using laser interferometer in patients with genetic ectopia lentis.

Methods: We treated a series of 18 patients (34 eyes) with genetic ectopia lentis whose visual acuity did not improve with optical phakic or aphakic correction, or with modern microsurgery and automated suction-cutting devices. Laser interferometry and electroretinogram (ERG) were used for the examination of retinal function before surgery.

Results: There was not significant difference between the interferometric acuity before operation and the corrected visual acuity after operation (p>0.05), and the coincidence rate between them was 80% (27 eyes). ERG examination showed normal function in most of the patients.

Conclusions: The results showed that the laser interferometric acuity is a valuable method in evaluation of postoperative visual acuity in patients with ectopia lentis. In six eyes, the LIVA was lower than the initial corrected vision postoperatively, but ERG examination showed that the retinal function was normal in these patients. Therefore, in patients with genetic ectopia lentis, LIVA combined with ERG predicts visual acuity more accurately.
Evaluation of Superior Oblique Weakening Procedures
Authors: Sharma Pradeep , Khokhar Sudarshan , Thanikachalam
Published: April 2021

ABSTRACT

Purpose: To evaluate two superior oblique weakening procedures, silicon expander (SE), and translational recession (TR), and their effects on correction of "A" pattern, vertical deviation in adduction and dorsoadduction, superior oblique overaction, and torsion.

Method: In a prospective, institution-based study, 32 eyes of 16 patients having bilateral superior oblique overaction with significant "A" pattern (>10 prism diopters [?]) were evaluated. The parameters studied were: change in "A" pattern; effect on vertical deviation in adduction and dorsoadduction; superior oblique overaction; and torsion.

Results: The index of surgical effect (ISE), showed 95% reduction in "A" pattern with SE and 92% reduction with TR, indicating equal effect in collapse of "A" phenomenon (p=0.78). The extorsion produced by TR was more than that produced by SE (P=0001).

Conclusions: Both the SE and TR procedures offered controlled weakening of the superior oblique and caused a 95% and 92% reduction in the "A" pattern. The latter procedure caused a marked extorsiona! change, three times that which resulted from SE. Both the procedures leave residual superior oblique overaction.

Journal of Pediatrie Ophthalmology and Strabismus 1999;36:189-195.
Cataract Surgery in Children With Uveitis
Authors: Paikos Peter , Fotopoulou Maria , Papathanassiou Miltiadis , Choreftaki Panagiota , Spyropoulos Grigorios
Published: April 2021

ABSTRACT

Purpose: To report the technique and postoperative results of cataract surgery in children with uveitis.

Method: Between 1988 and 1998, nine children (age range: 2.5-11 years) who developed secondary uveitic cataract and underwent cataract extraction were studied retrospectively. Seven children had juvenile rheumatoid arthritis and two had chronic anterior uveitis of unknown etiology. The surgical technique was lensectomy and wide anterior vitrectomy with limbal approach, lysis of anterior synechiae and in some cases, peripheral iridectomy. Postoperative aphakia was corrected with soft contact lenses in all patients. Follow-up ranged from 6 months to 6 years.

Results: Postoperatively, visual acuity in all patients improved and final visual acuity ranged from 20/70 to 20/25. Significant intraoperative complications did not occcur in any patient. One boy with juvenile rheumatoid arthritis developed cystoid macular edema 1 month postoperatively, which was successfully managed. He also developed hypertonia 1 year later, which was also successfully managed. Seven of the nine children had fewer and milder relapses of uveitis after surgery.

Conclusion: Cataract surgery, using the lensectomy-vitrectomy technique in children with uveitis, is a safe technique with a relatively small percentage of postoperative complications and good functional results.

Journal of Pediatric Ophthalmology and Strabismus 2001;38:16-20.
Normal Neonatal Values of Ophthalmic and Central Retinal Artery Blood Flow Velocities
Authors: Romagnoli Costantino , Papacci Patrizia , Zecca Enrico , Giannantonio Carmen , De Carolis Maria Pia , Tortorolo Giuseppe
Published: April 2021

ABSTRACT

Purpose: To define standard values of blood flow velocities and indices in the ophthalmic and central retinal arteries in the neonatal period.

Methods: Forty-two healthy full-term neonates comprised the study population. A color Doppler with mechanical sector probe was used for measuring blood flow velocity in the ophthalmic and central retinal arteries. Systolic, end diastolic, and mean-enveloped velocities were measured, and the resistance index and pulsatility index were calculated.

Results: Ophthalmic artery Doppler velocities were similar on the first and third days of life, but increased significantly on the fifth and seventh days of life; resistance index significantly increased during the first week of life, whereas pulsatility index did not change significantly. Doppler velocities of the central retinal artery were similar on the first and third days; they show a delayed increase compared to the ophthalmic artery. Central retinal artery blood flow velocities increased significantly from the third to seventh postnatal day. Resistance index also increased between the first two days and on the fifth and seventh postnatal days, while pulsatility index did not change.

Conclusion: These data constitute a starting point for studying the possible relationship between eye circulation and pathogenesis of retinopathy of prematurity.

Journal of Pediatric Ophthalmology and Strabismus. 2001;38:213-217.
Cystoid Macular Edema Associated With Juvenile Idiopathic Arthritis Resolved by a Dexamethasone Intravitreal Implant
Authors: Totan Yüksel , Güler Emre , Guragaç Fatma B. , Dervisogullari Mehmet S. , Tenlik Aylin , Hepsen Ibrahim F.
Published: April 2021

Uveitis, glaucoma, and cystoid macular edema frequently develop in patients with juvenile idiopathic arthritis. The authors describe a case of cystoid macular edema associated with juvenile idiopathic arthritis that had not responded to intravitreal triamcinolone acetonide and bevacizumab but improved significantly following intravitreal injection with a dexamethasone 0.7 mg implant.
[J Pediatr Ophthalmol Strabismus 2014;51:e25–e28.]
Clinical and Histopathological Features of Congenital Fibrovascular Pupillary Membranes in a Chinese Case Series
Authors: Liang Tianwei , Zhang Chengyue , Fu Libing , Hu Man , Zhang Lianxin , Li Li
Published: April 2021

Purpose:

To investigate the clinical and histopathological features of congenital fibrovascular pupillary membrane (CFPM) in Chinese patients.

Methods:

This retrospective study reviewed CFPM cases treated at Beijing Children's Hospital. The clinical manifestations, approaches of treatment, outcomes, and histopathological findings were collected and analyzed.

Results:

A total of 33 patients with CFPM were reviewed. All patients had unilateral eye involvement. A total of 21 eyes (63.64%) had a white membrane that partially covered the pupil and 12 eyes (36.36%) had a membrane that completely covered the pupil. Of the 12 eyes with a complete pupillary membrane, 6 (50%) had glaucoma. For eyes with a partial pupillary membrane, 11 eyes (52.38%) were followed up at the outpatient clinic without surgery and 10 eyes (47.62%) underwent membranectomy and pupilloplasty due to visual axis blockage. For the 12 eyes with a complete pupillary membrane, 6 eyes (50%) with normal intraocular pressure (IOP) received membranectomy and pupilloplasty combined with iridectomy, and 1 (16.67%) of these 6 eyes underwent a reoperation after 5 months due to a recurrent membrane. Furthermore, 6 eyes (50%) with glaucoma had membranectomy, pupilloplasty, iridectomy, and goniosynechialysis. Among these 6 eyes, 2 eyes (33.33%) underwent a reoperation due to the recurrence of a membrane and 4 eyes (66.67%) had a pale optic disc. The histopathological findings revealed that these membranes were mainly composed of fibrous tissue, lymphocytes, pigment epithelial cells, and vascular tissues.

Conclusions:

CFPM has diverse manifestations, including a partial pupillary membrane, a complete pupillary membrane with normal IOP, and a complete pupillary membrane with glaucoma. Timely diagnosis and treatment are critical when the visual axis is blocked and/or the IOP is high.

[
J Pediatr Ophthalmol Strabismus
. 2021;58(2):105–111.]
Clinical and Electrophysiological Outcomes After Eye Muscle Surgery in 81 Adults With Infantile Nystagmus Syndrome
Authors: Hertle Richard W. , Curtis Molly , Boydstun Ian , Juric Ana , Evliyaoglu Ferhat , Ricker Isabel
Published: April 2021

Purpose:

To characterize the effects of eye muscle surgery on patients older than 18 years with infantile nystagmus syndrome (INS) who have had only optical treatment.

Methods:

This was a prospective, single-center, interventional case series analysis of clinical and electro-phyisological data before and after surgery. Outcome measures included: clinical characteristics, surgical procedure, and preoperative and postoperative binocular best corrected visual acuity (BCVA) in the null position, anomalous head posture (AHP), contrast sensitivity, strabismic deviation, and nystagmus acuity function (NAFX). Postoperative data used were collected for a minimum of 12 months after surgery. Parametric and non-parametric statistical analysis of the outcome measures was performed.

Results:

Ages ranged from 18 to 72 years (average: 36 years) and follow-up from 12 to 74 months (average: 26 months). A surgical algorithm of nine separate procedures involving at least two recti muscles on each eye was used for each patient. Most patients had associated systemic and/or ocular diagnoses, including albinism (35%), amblyopia (23%), optic nerve or retinal disorders (48%), refractive error (80%), AHP (44%), aperiodicity (27%), and strabismus (69%). There were no serious surgical complications, with a reoperation rate of 12%. There were significant group mean increases in BVCA, AHP, contrast sensitivity, strabismic deviation, and NAFX after surgery. Sixty percent of patients who were legally ineligible for driving prior to surgery became eligible after eye muscle surgery.

Conclusions:

Adult patients with INS showed sustained improvement in many afferent and efferent measures of visual function after eye muscle surgery.

[
J Pediatr Ophthalmol Strabismus
. 2021;58(2):93–104.]
The Perceptual Characteristics of Juvenile Delinquents*
Authors: Petrie Asenath , McCulloch Rook , Kazdin Phoebe
Published: April 2021

EDITORIAL NOTE:

This research merits more than one reading with particular attention to the technique described and studied consideration should be given to the psychological implications of Reducer-Augmenter in regard to planning patient activities on nursing units. This research suggests a technique which could provide a more scientific approach to planning therapeutic activities for patients. Psychiatric Nursing needs more specific methods and techniques to better establish the therapeutic activities to be provided. This could be one to be further researched by psychiatric nurses to determine its application to patient care planning at the ward level.
Nursing is an Interpersonal Experience
Authors: Hays Joyce Samhammer , Krikorian Diana
Published: April 2021

Prior to beginning clinical experience, freshman students-in the baccalaureate nursing program of the University of Pennsylvania-were asked to submit papers expressing their thoughts about nursing. This paper presents a composite picture of those thoughts.
Recent Reports: An International Potpourri
Authors: David Henry P
Published: April 2021

INTERNATIONAL TRENDS
"Reward Education and Experience," Nurses Say
Authors: Anonymous
Published: April 2021

Nursing Economics

Panel calls for career ladders, graduated salary scales, and PR
First Annual APNA Convention Held in Baltimore
Authors: Anonymous
Published: April 2021

Workshops cover wide range of psychosocial topics
NURSING CARE CHALLENGES: Homosexual Psychiatric Patients
Authors: Smith George Byron
Published: April 2021

There are at least 20 million lesbians and gay men living in the United States today (Curry, 1988). According to the famous Kinsey study on sexuality, approximately 10% of the population is homosexual (Carl, 1990). However, the exact number of gay individuals is difficult to ascertain due to the social stigma of homosexuality.
Levels of Recovery From Psychotic Disorders Chart
Authors: Sousa Sharon
Published: April 2021

The Levels of Recovery From Psychotic Disorders Chart was developed by this author at the request of the Massachusetts Alliance for the Mentally III (AMI). This chart is used to assess and treat patients' recovery from psychotic illnesses. By using the chart in a process of periodic assessment, patients, their families, and clinicians are prompted to consider alternative antipsychotic medications that might potentiate recovery. This article describes the development of the chart, methods of recording observations, clinical recommendations based on the chart, and implications for nursing.
THE ASTRONAUT'S WIFE
Authors: Anonymous
Published: April 2021

Lessons of Growth Through Spousal Depression
Reclaiming Control in Stalking Cases
Authors: Spitzberg Brian H
Published: April 2021

ABSTRACT

Some common myths about stalking are debunked on the basis of research. In light of such research, stalking is examined in terms of its prevalence, the degree to which it is a gendered phenomenon, the tactics stalkers use in their pursuit, the effects of such unwanted pursuit on victims, and the tactics victims typically use to manage such pursuit. Recommendations are made regarding these strategies.
Ten Years Experience With a Conservative Approach to Radial Keratotomy
Authors: Salz James J , Salz James M , Salz Mark , Jones Donna
Published: April 2021

ABSTRACT: This retrospective study reports the results of radial keratotomy surgery on 225 eyes of 135 patients by one surgeon. Fifty-one percent of the eyes had four incisions and 45% had eight as the initial procedure. Fifteen percent of the eyes repeated surgery. The mean preoperative spherical equivalent refraction was -5.10 diopters (SD 1.90, range 1.20 to 11.60 D) and at 3 months to 1 year, the mean was -0.60 D (SD 1.00, range -4.80 to +3.40 D). For the entire series, 69% of the eyes achieved an uncorrected visual acuity of 20/40 or better, 73% were corrected to within ±1.00 D of emmetropia, and 3% were overcorrected by more than +1.00 D. For eyes with low preoperative myopia (-3.00 D and less), 100% achieved an uncorrected visual acuity of 20/40 or better, 97% were corrected to within ±1.00 D of emmetropia, and 3% were overcorrected by more than +1.00 D. For eyes with moderate myopia (-3.1 to -5.9 D), 73% achieved an uncorrected visual acuity of 20/40 or better, 81% were corrected to within ±1.00 D of emmetropia, and 3% were overcorrected by more than +1.00 D. For eyes with higher preoperative myopia ( -6.0 to -11.60 D), 47% achieved an uncorrected visual acuity of 20/40 or better, 45% were corrected to within ±1.00 D of emmetropia and 3% were overcorrected by more than +1.00 D. One hundred eyes with a follow-up of 2 years or greater were studied for stability; 77% changed by less than 1.00 D from the 1 year value; 17% changed by 1.00 D or more in the hyperopic direction; 6% changed by 1.00 D or more in the myopic direction. There were no vision threatening complications and only one eye had a postoperative best spectacle corrected visual acuity of less than 20/40. [Refractive and Corneal Surgery 1991;7:12-22.]
A Study of the Optical Micrometer, the Coin Gauge, and the Diamond Knife Micrometer in Diamond Knife Calibration
Authors: Au Yue-Kong , Reynolds Mark D , Chadalavada Ravi C
Published: April 2021

ABSTRACT: Reproducible results in refractive keratectomy are greatly influenced by an accurate setting of the diamond knife blade length. In this study, we evaluated the accuracy and reproducibility of three existing techniques of blade calibration: the KOI coin gauge, the KOI diamond knife handle micrometer, and the Magnum optical micrometer. Serial blade length measurements of three similarly designed KOI diamond knives were made using each of the above calibration methods. The three knife handle micrometers had the largest measurement error (3.55%, 2.83%, 1.82%), and therefore the sole reliance of the handle micrometer for blade calibration was not recommended. The measurements made by the coin gauge on the three knives had measurement errors of 1.03%, 1.64%, and 1.46%. The optical micrometer achieved an accuracy of 0.005 mm and an interobserver precision of 0.009 mm. We prefer using the optical micrometer because the potential for parallax error is eliminated; it has a lower risk of blade damage; it is easier to use; and it also allows detection of defects in the footplates, the diamond knife, and of the wobbling blade, which may contribute to calibration erroURefracf Corneal Surg 1991 ;7:299-302.)
Subregions of Differing Refractive Power Within the Clear Zone After Experimental Radial Keratotomy
Authors: Lopez Pedro F , Maloney Robert K , Goodman Gerri G , Stark Walter J
Published: April 2021

ABSTRACT: After radial keratotomy (RK), some patients experience a mild decrease in best corrected visual acuity, visual distortion, or monocular diplopia. These optical effects of radial keratotomy are best explained by subregions of different refractive powers within the surgery-free clear zone. To investigate the topography of the clear zone, we performed four- and eight-incision radial keratotomy in eight cadaver eyes. After radial keratotomy, we found subregions within the clear zone of two types: 1) small, very flat regions at the ends of the radial incisions (seven of eight eyes), and 2) a series of concentric rings centered on the visual axis with a continuously progressive decline in refractive power toward the periphery of the clear zone (all eyes). The clear zone after radial keratotomy is often nipple-shaped, with a more myopic segment centrally and a more hyperopic region near the periphery of the clear zone. (Refract Corneal Surg 1991;7:360-367.)
Corneal Topographic Changes Induced by Pterygia
Authors: Pavilack Mark A , Halpern Barton L
Published: April 2021

ABSTRACT

BACKGROUND: This study characterizes the topographic changes induced by pterygia.

METHODS: Using data obtained from a videokeratoscope (TMS-1), we assessed the topographic changes of corneas from 24 consecutive eyes with pterygia.

RESULTS: Each pterygium induced a localized area of flattening central to its apex of 38.00 ± 2.80 diopter (D) which was significantly flatter (p < .0001) than the mean corneal power (43.70 ± 1.70), minimum corneal power (MinK, 42.70 ± 2.10), and the power of the flattest corneal meridian (42.90 ± 1.90).

CONCLUSIONS: Our topographic findings characterize an area of localized corneal flattening central to the apex of pterygia. It is not known if this pterygium-associated corneal flattening influences the centripetal growth of pterygia or their tendency not to cross the visual axis. [J Refract Surg. 1995;11:92-95.]
Repeatability of Corneal Topography: The "Corneal Field"
Authors: Zadnik Karla , Friedman Nina E , Mutti Donald O
Published: April 2021

ABSTRACT

BACKGROUND: The purpose of this study was to determine the interoccasion repeatability of keratometry, photokeratography, and videokeratography and to describe the "corneal field," a scheme for explaining videokeratography results.

METHODS: A single examiner obtained corneal curvature measurements with a keratometer, a photokeratoscope, and the TMS-1 in 29 adult patients on two occasions.

RESULTS: Estimates for the repeatability of keratometry were ±0.49 and ±0.65 diopters (D) for the horizontal and vertical meridians respectively. The repeatability of photokeratography was ±0.90 and ±1.21 D. We presented a rational method for presenting numeric videokeratographic data by temporally and spatially averaging corneal curvature values and grouping them into 24 regions. The repeatability of videokerategraphy with the TMS-1 was ±0.50 D centrally, ±0.65 D paracentrally, and ±0.80 to ±1.00 D in the midperiphery.

CONCLUSIONS: Repeatability of the photokeratoscope for central measurements is considerably worse than the keratometer. The repeatability of videokeratography is worse toward the periphery. Refractive surgeons and contact lens investigators need to be aware of these limitations so that true change can be distinguished from measurement error.[J Refract Corneal Surg 1995;11:119-125.]
Laser In Situ Keratomileusis for Myopia Using Manual Dissection
Authors: Gomes Marcos
Published: April 2021

ABSTRACT

Forty-two eyes underwent interlamellar photoablation, a simple method of exposing the stroma to excimer laser treatment using common surgical instruments. A 8 mm diameter line up to 200 µm thick is raised manually from its bed. The stromal bed is reshaped with the excimer laser, and restoring the disc results in correction of high myopia. Our own nomogram was used.

This method allows the use of less corticosteroids and final visual acuity recovers between 20 and 90 days postoperatively, time required for interface adherence and epithelial remodeling. Two treatment zones were used when 80% of the patient's myopia was greater than 10.00 diopters (D). One-year follow-up data allowed us to conclude that this method achieved results similar to excimer laser in situ keratomileusis (LASIK). [J Refract Surg. 1995;11 (suppl.):S239-S243.]
Excimer Laser Photorefractive Keratectomy For Myopia: Two-year Follow Up
Authors: Amano Shiro , Shimizu Kimiya
Published: April 2021

ABSTRACT

This study, comprising 60 eyes with a follow up of at least 2 years, was designed to evaluate the efficacy and safety of excimer laser photorefractive keratectomy (PRK) for myopia in Japanese people. Eyes were divided into three groups: low myopia group (-2.00 diopters (D) to -3.00 D), 11 eyes; medium myopia group (-3.10 D to -6.00 D), 28 eyes; and high myopia group (-6.10 D to -14.00 D), 21 eyes. In 60 eyes, uncorrected visual acuity improved and spectacle corrected visual acuity remained unchanged. At 2 years, 100%, 75%, and 52%, respectively, of the low, medium, and high myopia groups, were within ± 1.00 D of the attempted correction. Twenty-two eyes (37%) developed corneal haze of grade 2 or more. These data show that in low or medium myopia the predictability is good. But we think we have to pay attention to the strong haze, which seems to have developed more frequently in Japanese people than in previous reports of PRK in Caucasians. [J Refract Surg. 1995;11 (suppl): S253-S260]
The Effect of Spherical Photorefractive Keratectomy On Myopic Astigmatism
Authors: Loewenstein Anat , Lipshitz Isaac , Lichtenstein Florina , Ben-Sirah Ayala , Lazar Moshe
Published: April 2021

ABSTRACT

The aim of this report is to present the effects of spherical photorefractive keratectomy (PRK) by excimer laser on myopic astigmatism.

Spherical PRK was performed in 96 eyes with myopia associated with astigmatism of between 0.75 and 2.00 diopters (D) using the Summit excimer laser.

The reduction both in sphere and in cylinder was found to be highly statistically significant (P<0.0001 for both). The mean reduction of cylinder was 46%.

Astigmatic error of less than 2.00 D can be corrected significantly by spherical PRK. [J Refract Surg. 1995;11(suppl.):S263-S264.]
Multizone Photorefractive Keratectomy for Myopia of 8 to 23 Diopters
Authors: Rajendran Babu , Janakiraman P
Published: April 2021

ABSTRACT

Multizone photorefractive keratectomy (PRK) was performed on 124 eyes of 69 patients for the treatment of high myopia using 4.5 mm, 5.0 mm, and 6.0 mm diameter ablation zones. Preoperative spherical equivalent refractions ranged from -8.00 diopters (D) to -22.5 D (mean ± SD, -12.3 ± 3.9 D).

Mean attempted ablation depth was 109.5 ± 37.8. Follow up ranged from 6 to 9 months. An uncorrected visual acuity of 20/60 or better was achieved in 63% of eyes and 20/40 or better in 48% of eyes. Sixty-seven percent of eyes achieved their pretreatment spectacle corrected visual acuity or were within two Snellen lines of it at 6 months postop.

Subepithelial haze was mild in 23% of eyes and moderate in another 34% of eyes. This cleared without a trace in almost all of these eyes within 6 months. Twenty-five percent of the eyes had dense scars and required reablation. [J Refract Surg. 1995; 11 (suppl.) :S298-S301.]
Regional Variation in Corneal Topography and Wound Healing Following Photorefractive Keratectomy
Authors: Grimm Bradford , Waring George O , Ibrahim Osama
Published: April 2021

ABSTRACT

BACKGROUND: After excimer laser photorefractive keratectomy, corneal epithelial and anterior stromal wound healing may produce corneal haze and variability in refractive results among patients and eyes.

METHODS: We report a retrospective study of 17 selected eyes that received excimer laser photorefractive keratectomy with one of three brands of laser and that exhibited regional variations in corneal wound healing as observed with slit-lamp microscopy and videokeratography (Tomey TMS) within the ablation zone.

RESULTS: All 17 eyes were selected to show that the clear areas in the ablation zone corresponded with flat zones on the videokeratographs and the areas of subepithelial haze corresponded with steeper zones. Spectacle-corrected visual acuity was measured in 12 of the 17 eyes, and was 20/20 or better in 58% and 20/30 or better in 100%, indicating that the regional variation did not severely degrade Snellen visual acuity. Further studies are needed to determine how often regional variability occurs and to better define the relationship of corneal haze and corneal curvature.

CONCLUSION: Regional variations in corneal topography and haze can occur within the ablation zone in an individual cornea after photorefractive keratectomy. [J Refract Surg. 1995;11:348-357.]
Correction of Myopia With Er:YAG Laser Fundamental Mode Photorefractive Keratectomy
Authors: Jean Benedikt , Kriegerowski Martin , Matallana Michael , Bende Thomas
Published: April 2021

ABSTRACT

BACKGROUND: Photorefractive keratectomy (PRK) has been performed with the ultraviolet 193 run radiation of the excimer laser. Due to its high absorption in water (3 µm water absorption band), the Er:YAG's 2.94 µm wavelength in the mid-infrared also qualifies for photoablation.

METHODS: A new laser source, providing an output energy of 2.6 J (multimode) and 380 mJ in the fundamental mode, was used to perform corneal areal ablation (large) in two blind human eyes eccentrically. The fundamental mode provided a Gaussian-shaped beam profile, able to ablate more tissue centrally, depending on the fluence applied.

RESULTS: The visible ablation diameter (opaque area) at the corneal surface was about 5 mm. Its effective ablation diameter was 4.85 ± 0.2 mm. The maximal ablation depth was 155 ± 5 µm. Surface roughness was 0.73 ± 0.06 µm, as assessed by a corneal silicone replica and subsequent confocal laser topometry.

Intraoperatively, the ablation site turned opaque, clearing after a couple of minutes. The resultant surface was rough; epithelization was uneven but not delayed. Postoperative pain was reported to be minimal. Subepithelial reactions were comparable to a 3+ haze and showed bubble-like inclusions, which slowly disappeared. By week 4, the corneal surface was even; a 1+ subepithelium haze persisted in case 1, while a clear ablation site was seen in case 2.

CONCLUSION: Areal corneal ablation with an Er:YAG laser that emits mid-infrared wavelengths seems possible. Although the thermally induced collateral damage is more pronounced, the wound healing pattern is comparable to 193 am PRK. This preliminary result has to be confirmed in normal eyes. [J Refract Surg. 1995;11:392-396.]
Oblique Versus Vertical-Horizontal Incision Orientation in Four-Incision Radial Keratotomy
Authors: Burillon C , Guigon B , Durand L
Published: April 2021

ABSTRACT

BACKGROUND: Four-incision radial keratotomy is used for the correction of mild to moderate myopia. The traditional orientation of incisions was naturally on the horizontal and vertical meridians. We undertook a comparative study of oblique versus traditional four-incision radial keratotomy (orthogonal orientation) to show the advantage of an oblique incision orientation.

METHODSi A prospective study of two groups of 21 eyes was conducted: an orthogonal group with vertical-horizontal orientation of the four incisions, and an oblique group with four obliquely oriented incisions. Spatial contrast sensitivity, glare, and night vision tests were performed and results compared. The follow up period was 3 months.

RESULTS: Glare and contrast sensitivity were less affected with oblique orientation of incisions. There was no significant difference regarding night vision effects. We observed a decrease in induced astigmatism with oblique orientation.

CONCLUSION: The location of horizontal incisions within the palpebral fissure and the unequal lengths of horizontal and vertical incisions are responsible for ocular alterations. An oblique orientation is preferable to avoid glare, starburst, and induced astigmatism. [J Refract Surg. 1995;1 1:453459.]
Do Three-Piece PMMA IOLs Rotate After Implantation In the Capsular Bag?
Authors: Werblin Theodore P
Published: April 2021

ABSTRACT

BACKGROUND: With the current interest in toric intraocular lenses (IOLs), it is critical to establish whether these implants rotate following cataract surgery. If there is continual rotation of the implant with capsular bag contraction, then the orientation of the astigmatic correction would be unstable and thus not clinically useful.

METHODS: Twenty-eight eyes were followed for up to 6 months postoperatively. These consecutive eyes were selected on the basis of demonstrating adequate dilatation following surgery, such that the points of haptic to optic insertion could be visualized with the slit-lamp microscope. Sequential photographs and comparisons of the orientation of the lenses postoperatively were performed.

RESULTS: With the exception of one lens implant, none of the 28 IOLs demonstrated significant rotation. Of the 16 eyes followed for 6 months, none demonstrated rotation of greater than 4 degrees, which was within experimental error.

CONCLUSIONS: Continued rotation of PMMA IOLs following implantation in the capsular bag seldom occurs. Thus, the concept of toric IOLs appears to be quite usable. [J Refract Surg. 1995;11:468-471.]
Combined Wedge Resection and Relaxing Incisions for Astigmatism After Penetrating Keratoplasty
Authors: Belmont Sandra C , Lazzaro Douglas R , Muller Jacqueline W , Troutman Richard C
Published: April 2021

ABSTRACT

BACKGROUND: Videokeratography may provide information for surgical correction of astigmatism after penetrating keratoplasty. We used a combination of wedge resection and relaxing incisions to treat high refractive astigmatism after penetrating keratoplasty.

METHODS: Videokeratography using the normalized scale of the Topographic Modeling System was used as a guide in determining the location and the length of incisions and resections. Nine eyes were treated with both relaxing incisions and a wedge resection. All patients had more than 3.00 diopters (D) of refractive astigmatism. All patients were intolerant of spectacles or contact lenses. The depth of the corneal relaxing incisions was constant at 0.5 mm and the width of the corneal wedge resections was constant at 0.75 mm.

RESULTS: The relaxing incisions produced flattening of the steeper meridian and the wedge resection produced steepening of the flatter meridian. The average preoperative keratometric astigmatism was 7.44 D (range, 3.50 to 11.00 D) and the average refractive astigmatism was 5.56 D (range, 4.00 to 8.00 D). The average preoperative spherical equivalent was 0.08 D (range, -7.00 to 4.25 D). Postoperatively, the average keratometric astigmatism was 2.97 D (range, 1.00 to 5.00 D) and the average refractive astigmatism was 2.58 D (range, 0.00 to 5.00 D). The average postoperative spherical equivalent refraction was -0.32 D.

CONCLUSIONS: Combined corneal wedge resection and relaxing incisions appears to be effective in reducing high refractive astigmatism following corneal transplantation. [J Refract Surg. 1995;11:472-476.]
Epikeratoplasty for Myopia: 2-year Results and a Proposed Nomogram
Authors: Choi Sangkyung , Lee Jin H
Published: April 2021

ABSTRACT

BACKGROUND: Epikeratoplasty for myopia is a relatively safe and reversible surgical technique that can result in large refractive corrections. However, it is also claimed that long-term stability and predictability are not satisfactory due to refractive regression and undercorrection.

METHODS: In an effort to improve predictability and stability of epikeratoplasty for myopia, we followed 24 cases for 2 years and isolated factors affecting the postoperative refractive results.

RESULTS: We found that better refractive results were achieved at 24 months postoperatively for cases in which the power of preoperative myopia was lower. Our investigations also disclosed no significant correlation between the surgical outcome at 24 months and patients' sex, age, and preoperative keratometric readings.

CONCLUSION: On the basis of our observations, we propose a new nomogram where higher powers of minus keratolenses, compared to the traditional prescription chart, should be selected for those with high preoperative myopia to result in improved long-term results with epikeratoplasty for myopia. This nomogram has not yet been clinically tested. [J Refract Surg. 1995;11:497-501.]
In Vivo Evaluation of a Collagen Corneal Allograft Derived From Rabbit Dermis
Authors: Kornmehl Ernest W , Bredvik Brian K , Kelman Charles D , Raizman Michael B , DeVore Dale P
Published: April 2021

ABSTRACT

BACKGROUND: This study evaluates epithelialization, clarity, intraocular inflammation, and fibroblast ingrowth of a collagen corneal allograft derived from rabbit dermis.

METHODS: Dermal collagen fibers were dispersed intact and chemically modified to make them soluble. The allografts consisted of a fibrous, opaque peripheral zone and a central clear area. Twelve New Zealand white rabbits underwent penetrating keratoplasty with implantation of an allograft. The grafts were evaluated daily for clarity, anterior segment inflammation, and extent of reepithelialization with a slit-lamp microscope.

RESULTS: Epithelialization of the fibrous peripheral zone of the graft ranged from 0% to 90%. The central clear area did not epithelialize in any of the animals. Fibroblasts migrated into the peripheral zone in all eyes. Complications included ulceration of the central clear area in two eyes. There was no ulceration or leakage at the graft-host interface and no synechia, fibrous, or inflammatory retrocorneal membranes in any of the eyes.

CONCLUSIONS: Our study is the first to describe the method of modifying dermal type I collagen into a clear corneal allograft. Survival of the corneal collagen allograft beyond 1 month may be limited by several factors including lack of epithelialization of the central clear area. [J Refract Surg. 1995;11:502-506.]
Limitations of Erbium:YAG Laser Photorefractive Keratectomy
Authors: Mrochen Michael , Semshichen Vladimir , Funk Richard H W , Seiler Theo
Published: April 2021

ABSTRACT

PURPOSE: The erbium:YAG laser (λ = 2.94 /¿m) has been considered promising as an alternative to the ArF excimer laser in photorefractive keratectomy (PRK). However, corneal application of this mid-infrared solid state laser is still plagued with various disadvantages compared to that of the ArF excimer laser (λ = 193 nm). We discuss the limitations of PRK with the erbiunuYAG laser.

METHODS: Measurements of ablation threshold, ablation efficiency, and thermal damage were done to compare the process of erbium:YAG laser photoevaporization to the ArP excimer laser. PRK procedures were performed on fresh enucleated pig corneas to investigate the morphology and surface roughness of the cornea after scanning-spot and fundamental mode photoablation. Surface roughness was measured by using a tactile surface reprofiling system.

RESULTS: The ablation threshold and the ablation efficiencies for the erbium:YAG laser are significantly higher compared to the ArF excimer laser. Collateral thermal damage decreases with a reduction of laser pulse duration to a minimum of approximately 5 /im. Scanning electron microscopy and surface roughness measurements of the corneal surface after erbiunuYAG laser treatment demonstrated higher surface roughness compared to ArF excimer laser treatments.

CONCLUSIONS: The erbium.YAG laser is not at present an alternative to the ArF excimer laser for photorefractive keratectomy. [J Refract Surg 2000;16:51-59]
Results of Photorefractive Keratectomy in Keratoconus Suspects at 4 Years
Authors: Bilgihan Kamil , Özdek Sengül C , Konuk Onur , Akata Fikret , Hasanreisoglu Berati
Published: April 2021

ABSTRACT

PURPOSE: We studied the long-term results of photorefractive keratectomy (PRK) in keratoconus suspects detected by videokeratography (TMS).

METHODS: Bilateral inferior corneal steepening was detected in 6 candidates for PRK presenting with moderate myopia or astigmatism. Mean follow-up was 44.5 ± 4.4 months (range, 38 to 54 mo). Mean spherical equivalent refraction was -5.18 ± 1.60 D (mean sphere, -4.73 D; mean cyclinder, -0.92 D) which was stable for at least the preceding year. The quantitative measurement of inferior corneal steepening (I-S value) was greater than +1.60 (mean, 1.83 ± 0.11) in all eyes. An Aesculap Meditee Mel 60 excimer laser was used for the PRK procedures and mean follow-up was 44.5 months. Postoperative pachymetric measurements were also performed in 6 eyes.

RESULTS: Postoperative uncorrected visual acuity was 20/20 in 8 eyes (66.6%) and 20/32 or better in all eyes with a mean postoperative spherical equivalent refraction of -0.70 ± 0.74 D (mean sphere, -0.63 D; mean cyclinder, -0.39 D). Five eyes (41.6%) were within ±0.50 D spherical equivalent refraction. Inferior steepening was associated with thinning of the inferior cornea which was statistically significantly thinner than the superior thickness (Student's f-test, P < .05). There were no wound healing problems or any sign that the excimer laser adversely affected the cornea during follow-up.

CONCLUSIONS: Photorefractive keratectomy seems to be a safe procedure for reducing or eliminating myopia or astigmatism in keratoconus suspect eyes - most probably forme fruste keratoconus- with a stable refraction, but this may be different in eyes with early keratoconus, known to be a progressive disease. [J Refract Surg 2000; 16:438-4431
Implantation of a New Accommodative Posterior Chamber Intraocular Lens
Authors: Küchle Michael , Nguyen Nhung X , Langenbucher Achim , Gusek-Schneider Gabriele C , Seitz Berthold , Hanna Khalil D
Published: April 2021

ABSTRACT

PURPOSE: A new, potentially accommodative posterior chamber lens (PCIOL) was designed based on principles elaborated by Hanna using finite element computer simulation methods. We report 3-month postoperative results in patients.

METHODS: In a prospective study, 12 eyes of 12 patients (age 45 to 87 yr) underwent phacoemulsification for cataracts and PCIOL implantation. The PCIOL, 1 CU, has haptics designed for anterior optic movement following ciliary muscle contraction. Patients were examined postoperatively after 1 and 2 days, 1, 2 and 6 weeks, and 3 months, and results were compared with a control group of 12 eyes that received standard PMMA or acrylic PCIOLs.

RESULTS: Surgery was uncomplicated and all PCIOLs were well-tolerated and stable with good centration in the capsular bag. The results were (mean ± SD [range] and median; 1 CU versus control PCIOL): near visual acuity (Birkhäuser reading chart at 35 cm) with best distance correction 0.34±0.17 (0.2 to 0.6), 0.3 (J10-J1, median J7) versus 0.15±0.07 (0.1 to 0.3), 0.15 (J16-J7, median J13), P=.001; subjective near point 59±10 cm (40 to 100 cm), 53.5 cm versus 93±20 cm (64 to 128 cm), 86 cm, P=.004; retinoscopic accommodative range 1.2 ± 0.4 D (0.63 to 1.5 D), 1.2 D versus 0.2±0.19 D (-0.25 to 0.5 D), 0.25 D, P<.001; decrease of anterior chamber depth after 2% pilocarpine 0.63±0.16 mm (0.40 to 0.91 mm), 0.63 mm versus 0.15±0.05 mm (0.08 to 0.20 mm), 0.17 mm, P<.001.

CONCLUSIONS: The new PCIOL appears to be safe at short to medium term. Our results indicate pseudophakic accommodation secondary to focus shift with this PCIOL. Additional larger and long-term studies are necessary for exact evaluation of safety and accommodative power of this new PCIOL. [J Refract Surg 2002;18:208-216]
Laser in situ Keratomileusus for Mixed and Simple Myopic Astigmatism With the Nidek EC-5000 Laser
Authors: Rueda Lizbeth , Pineda-Fernández Angel , Huang David , Nur Jorge
Published: April 2021

ABSTRACT

PURPOSE: To evaluate the visual and refractive results of laser in situ keratomileusis (LASIK) for mixed and simple myopic astigmatism using bitoric ablation.

METHODS: A retrospective study was performed in 65 eyes of 38 consecutive patients to evaluate uncorrected (UCVA) and best spectacle-corrected visual acuity (BSCVA) and cyclopegic and manifest refraction, before and 3 and 6 months after LASIK (Moria LSK-ONE microkeratome, Nidek EC-5000 excimer laser).

RESULTS: At 3 and 6 months after LASIK, 40 eyes of 24 patients (64.5%) were available for follow-up examination. Mean age was 25.9 ± 6.6 years (range 18 to 43 yr). Mean preoperative manifest spherical equivalent refraction was -1.40 ± 0.80 D (range -3.80 to +0.50 D), mean preoperative cylinder was -3.30 ± 1.30 D (range -1.00 to -6.00 D). At 6 months follow-up, mean manifest spherical equivalent refraction was +0.30 ± 0.46 D (range -0.38 to +1.88 D), mean cylinder was -0.73 ± 0.61 D (range -2.25 to 0 D). There was a 77.8% decrease in astigmatism magnitude. According to vector analysis, mean achieved vector magnitude was 80% of intended. Fifty percent (20 eyes) had a cylinder within ±0.50 D of emmetropia. Twenty-three eyes (57.5%) had a spherical component within ±0.50 D. Eighty-five percent (34 eyes) had postoperative UCVA of 20/40 or better. Ten percent (four eyes) lost two lines of Snellen BSCVA, whereas 35% (14 eyes) gained one or more lines.

CONCLUSIONS: Bitoric LASIK with the Moria LSK-ONE microkeratome and Nidek EC-5000 excimer laser was effective and safe for the reduction of cylinder in mixed and simple myopic astigmatism. Moderate undercorrection of the cylinder was evident. [J Refract Surg 2002;18: 234-238]