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1.
PURPOSE: The purpose of the study is to evaluate the myopic shift that occurs in children 3 to 9 years of age who undergo cataract extraction with primary intraocular lens (IOL) implantation. METHODS: A review of 18 children (mean, 6.3 +/- 0.5 year; range, 3-9 years) who had undergone primary IOL implantation was undertaken. Patients were observed for an average of 3.2 years. The initial and last postoperative refractive errors were compared. RESULTS: The mean myopic shift was -0.99 +/- 0.22 diopter (D) (median, 1.0 D) with a range of -3.25 to +0.38 D. The difference in the myopic shift of the children 3 to 5 years of age (-0.94 +/- 0.30 D) was not significantly different from the myopic shift occurring in the children 6 to 9 years of age (-1.07 +/- 0.35 D). The myopic shift was less than 1.5 D in 70% of the eyes and only 3 eyes had a myopic shift greater than 2 D. Ninety percent of the children achieved a visual acuity of 20/40 or better in their pseudophakic eye or eyes. CONCLUSIONS: Although each patient should be evaluated on an individual basis, the authors recommend undercorrecting most children 3 to 9 years of age by 1 D from the IOL power predicted to achieve emmetropia.  相似文献   

2.
PURPOSE: To report refractive changes after cataract surgery and intraocular lens implantation in infants and children. METHODS: In an ongoing prospective study, the refractive errors of all patients younger than 18 years undergoing intraocular lens implantation were determined at 6 weeks, 3 months, 6 months, and 1 year, and at least yearly thereafter. All patients with greater than 6 months of follow-up were included in the study. RESULTS: Eighty-three eyes of 81 patients were identified. Cataracts were traumatic in 32 eyes (38%) and developmental in 42 eyes (50%). At implantation, the mean (+/-SD) age was 6.3 +/- 4.6 years (range, 9 months to 17 years). The mean follow-up was 26.6 months (range, 6 months to 6.6 years). Patients 0 to 2 years old at the time of implantation demonstrated a mean myopic shift of -3.00 diopters during a mean follow-up period of 2.5 years. Patients 2 to 6 years old at the time of implantation demonstrated a mean myopic shift of -1.50 diopters in a similar follow-up period. Children aged 6 to 8 years experienced a mean myopic shift of -1.80 diopters during a mean follow-up period of 3.0 years, while children older than 8 years at the time of intraocular lens implantation experienced a mean myopic shift of -0.38 diopters during a mean follow-up period of 1.8 years. On average, the operated-on eye showed a greater mean myopic shift than the fellow eye. No statistically significant differences in refractive change were found in comparing amblyopic to nonamblyopic eyes, traumatic to nontraumatic cataracts, or primary to secondary intraocular lenses. CONCLUSIONS: Our data demonstrate a trend toward increasing postoperative myopia in pediatric patients undergoing intraocular lens implantation. This myopic shift is greatest in the younger age groups and persists until at least 8 years of age. There is much variability in the postoperative refractive changes, and predicting exactly when and where the refraction will stabilize for an individual patient is difficult.  相似文献   

3.
The two main possibilities of error of the generally used methods for artificial lens implantation after preoperative ultrasound measurements and calculations are discussed. By using our additional special calibration to the ultrasonic equipment we can predict the postoperative refraction with an error of +/- 0.5 D corresponding to an uncorrected vision of about 20/40 and better. Procedures based on the validity of Knapp's law may lead to optical pitfalls, since Knapp's law is only valid for eyes with variable eye length, while it is known that human phakic, pseudophakic and aphakic eyes have a constant eye length. Three principles for the precalculated artificial lens implantation are published and results of refractive balances are given.  相似文献   

4.
PURPOSE: To report results of secondary intraocular lens implantation after cataract surgery in children. METHODS: We reviewed clinical records for a 5-year period of patients who had cataract surgery in childhood and received a secondary intraocular lens implant. We studied indications for secondary intraocular lens placement; surgical procedures for intraocular lens implantation; preoperative and postoperative visual acuity, refractive error, and binocular status; and complications of the procedure. RESULTS: A secondary intraocular lens was placed in 28 eyes of 25 patients who had cataract surgery in childhood. In 20 eyes, the lenses were placed in the ciliary sulcus. The other eight eyes had insufficient capsular support for an intraocular lens; in two, the intraocular lens was placed in the anterior chamber and, in six, in the posterior chamber with suture fixation to the sclera. Twenty of 28 eyes (71%) had measurable improvement in visual acuity; only one eye had a decrease in visual acuity of 2 lines. Fifteen patients (54%) had a final refraction within 1.50 diopters of the fellow eye; 21 (75%) were within 3.00 diopters. During follow-up, two eyes developed glaucoma. One had transient pressure elevation; one required two filtration procedures. Three patients required Nd:YAG capsulotomy. Six patients demonstrated Worth fusion at distance and near; three demonstrated 200 seconds of arc or better stereo visual acuity. CONCLUSION: Secondary placement of an intraocular lens in the posterior chamber appears to be a safe, effective alternative for correction of aphakia in the contact lens- or spectacles-intolerant child or young adult.  相似文献   

5.
PURPOSE: To evaluate the role of lens epithelial cells (LECs) in posterior capsule opacification. SETTING: Departments of Ophthalmology and Pathology, Wakayama Medical College, Department of Anatomy, Kansai Shinkyu College, and Department of Ophthalmology, Kobe Kaisei Hospital, Japan. METHODS: We examined the presence of degenerated LECs on the capsules of the eyes of rabbits and a patient after intraocular lens (IOL) implantation. Phacoextraction of a crystalline lens and IOL implantation were done in 5 albino rabbits under general anesthesia. The animals were killed after 2 months. Lens capsules were removed and fixed. During vitreous surgery, a lens capsule with an IOL was removed from a patient. Ultrathin sections of specimens were studied by transmission electron microscopy. RESULTS: Presumed LECs proliferated between the posterior capsule and the IOL in association with collagenous matrix. Debris from the degenerated cells and destroyed intracellular organelles was also seen. CONCLUSION: Lens epithelial cells proliferating on the posterior capsule cannot survive indefinitely.  相似文献   

6.
Posterior chamber phakic intraocular lens (PCP IOL) implantation is an emerging refractive procedure. We report a case of cataract formation 6 months after uneventful implantation of a Staar PCP IOL to correct high myopia. Visual recovery was achieved after explantation of the phakic IOL and phacoemulsification with implantation of a foldable IOL through the same unenlarged self-sealing corneal incision.  相似文献   

7.
OBJECTIVE: To understand whether the binocular visual function could be restored after posterior chamber intraocular lens (IOL) implantation. METHODS: The visual function including corrected vision, simultaneous perception, fusion, stereoacuity, aniseikonia and retinal correspondence point were determined for 50 cases (64 eyes) after the surgery. RESULTS: The corrected visual acuities were 0.6 or better. Visual acuities of 1.0 or better were achieved in 65% and 0.6-0.9 in 35% of the eyes. All patients obtained simultaneous perception and fusion function. The near stereoacuity of 50 cases showed foveal stereoacuity < or = 60 seconds in 23 cases (46%), macular stereoacuity 80-200 seconds 10 cases (20%) and peripheral stereoacuity 400 seconds 17 cases (34%). The far stereoacuity of 50 cases comprised 34 cases of foveal stereoacuity (68%), 9 cases of macular stereoacuity (18%) and 7 cases of peripheral stereoacuity (14%). The postoperative retinal correspondence points were normal. There was no aniseikonia in 35 cases, except 15 cases of aniseikonia which was within normal tolerable limits. CONCLUSION: When binocular corrected vision is > or = 0.4 with ocular alignment, the binocular visual function could be restored for varying degrees.  相似文献   

8.
Mere aphakia is not an indication for secondary intraocular lens implantation. However, many patients with positive indications may be benefited most strikingly by this procedure. These indications are illustrated and results of the author's first 65 secondary implantations are analyzed.  相似文献   

9.
In 540 cases having undertaken extracapsular cataract extraction and intraocular lens implantation, a pupillary membrane developed in 76 cases, the rate of occurrence being 14%. Generally, the membrane appears on the fifth post-operative day and corticosteroids are effective in its treatment. After treatment no significant sequela is left and the corrected postoperative visual acuity is not affected. The pathogenesis, treatment and prognosis of the pupillary membrane are briefly discussed in the report.  相似文献   

10.
PURPOSE: To ascertain whether phacoemulsification with posterior chamber intraocular lens (IOL) implantation causes long-term reduction in intraocular pressure (IOP). SETTING: Private practice, Kempten, Germany. METHODS: Intraocular pressure was measured in both eyes of 120 consecutive patients who were unilaterally phakic after phacoemulsification a mean of 17 months +/- 17 (SD) previously. Mean age of the 36 men and 84 women was 76 +/- 10 years. Data were analyzed using binomial distribution and the Wilcoxon signed-rank test. RESULTS: The median ratio of IOP in the pseudophakic eye to IOP in the phakic eye was 0.83. The IOP was lower in the pseudophakic eye in 96 patients (80%). The median IOP was 12 mm Hg in the pseudophakic eyes and 14 mm Hg in the phakic eyes (P < .001). As measured by the interquartile range, IOP distribution was more centered in the pseudophakic than in the phakic eyes (3 versus 4). The IOP in the pseudophakic eyes remained lower to the last measurement, 5 years postoperatively, and appeared to be independent of patient age. Lower IOP in the pseudophakic eye was consistently present in patients with higher IOP in the phakic eye (16 to 22 mm Hg). CONCLUSION: Phacoemulsification with posterior chamber IOL implantation reduced IOP in most but not all patients with a preoperative IOP of 22 mm Hg or less. This reduction was maintained over several years, with the cause yet to be established. Lower IOP may decrease the risk of subsequent glaucomatous nerve damage in these patients.  相似文献   

11.
A 53-year-old man with keratoconus and an axial length of 32.59 mm had cataract extraction by phacoemulsification. The Holladay II formula called for -14.00 diopters (D) of power. Two negative-power intraocular lenses (IOLs) were implanted to optimize visual results. A 1 day postoperative refraction of +1.50 D sphere necessitated an exchange of the anterior IOL. Six days after the exchange, the patient had a refraction of -1.25 D sphere and best corrected visual acuity of 20/50.  相似文献   

12.
OBJECTIVE: The study was designed to determine the visual outcome and indication of secondary posterior chamber intraocular lens (IOL) implantation. METHODS: The operation was performed on 34 eyes with aphakia in children after separation of posterior iris synechia from posterior capsule and formation of a posterior chamber space large enough to insert an intraocular lens. Based on whether the integrity of the posterior capsule was complete or not, various techniques of secondary IOL implantation were adopted. RESULTS: The follow-up periods ranged from 6 to 24 months. The results showed that 29 of the eyes (85.29%) achieved a post-operative corrected visual acuity equal to or better than that of the best corrected visual acuity before the surgery; the postoperative uncorrected visual acuities in 16 eyes (47.06%) and corrected visual acuities in 28 eyes (82.35%) reached 0.5 or better. CONCLUSION: Secondary posterior chamber IOL implantation is a safe and effective method in children who have a complete or partial posterior capsule.  相似文献   

13.
Implantation of a posterior chamber phakic intraocular lens is an effective refractive procedure with a good safety record in the short-term follow-ups reported in the literature. Cataract formation is a potential complication of the procedure. Two patients developed lens opacities in 3 eyes after the procedure was performed for myopic astigmatism. The possible causes are discussed. This is not a dangerous complication as cataract extraction is easily achieved if necessary. However, it is undesirable and further research is required to assess the long-term incidence, causes, and ways to prevent its occurrence.  相似文献   

14.
15.
Endothelial physiology and intraocular lens implantation   总被引:1,自引:0,他引:1  
The endothelium is the cellular monolayer which lines the posterior surface of the cornea. This layer is important in clinical ophthalmology because it is vital to maintenance of the transparency of the cornea and vision through its pump and barrier functions which limit the ingress of fluid into the cornea from the aqueous. When the function of the corneal endothelium becomes compromised, the corneal stroma swells as it hydrates. Subsequently, epithelial bullae form with painful recurring epithelial erosions, and finally corneal scarring and blindness result. The relatively vulnerable position of the corneal endothelium renders it susceptible to iatrogenic injury during intraocular procedures, especially IOL implantation: the poor regenerative (mitotic) capacity of the human corneal endothelium limits its ability to recover normal function once it is injured.  相似文献   

16.
Identification of unknown bodies is mainly made by dental examination and comparison with accurate dental records. Therefore it is necessary to examine the jaws carefully and to locate every tooth-coloured dental restoration. Overlooking dental fillings can make positive identification impossible. The technique described prepares the natural dental hard tissue by etching with 37% phosphoric acid. In the next step an indicator colours the roughened dental tissue but not the polished restoration material. In this way all 15 tested dental restoration materials could be detected with high sensitivity.  相似文献   

17.
We have previously shown that mild hypothermia applied after hypoxia-ischemia in newborn piglets and rats reduces brain injury evaluated 3-7 d after the insult. The aim of the present study was to assess the neuroprotective efficacy of hypothermia with respect to short- (neuropathology) and long-term (neuropathology and sensorimotor function) outcome after hypoxia-ischemia in 7-d-old rats. One hundred fourteen animals from 13 litters survived either 1 or 6 wk after a hypoxic-ischemic insult. The animals were randomized to either 1) normothermic recovery for the whole 1- or 6-wk period or 2) cooling to a rectal temperature of 32.0 degrees C for the first 6 h followed by normothermic recovery with the dam. Hypothermia offered a uniform protection of 27, 35, 28, and 25% in cerebral cortex, hippocampus, basal ganglia, and thalamus, respectively, in the 1-wk survivors (n = 32). The corresponding values for the 6-wk survivors (n = 61) were 22, 28, 37, and 35%. There was a significant correlation between sensorimotor performance and infarct volume (r = 0.66; p < 0.001). However, the sensorimotor function was not significantly improved by hypothermia if all animals were included, but in female pups the total functional score was higher in the hypothermia group (150 +/- 35 versus 100 +/- 34, p < 0.0007) which corresponded to a marked (51%) reduction of the neuropathology score in this subgroup. This is the first neonatal study to show a long-term histopathologic protection of the brain after posthypoxic hypothermia.  相似文献   

18.
For a large scaled test 52 patients with anterior transposition of the ulnar nerve and 62 patients with elbow injuries were examined by questionnaire, physical examination and electroneurography. In conformity with existing literature 24 patients out of 52 suffering from cubital tunnel syndrome had an elbow trauma previously. To our great surprise in seven patients out of 46 with elbow injuries a cubital tunnel syndrome could be found for the first time. The cubital tunnel syndrome appears to be a frequent complication of elbow injuries. Besides the well known fractures of the medial epicondyle and pericondylar fractures leading to cubital tunnel syndrome, in our study fractures of the head of the radius and processus coronoideus were found quite often. Patients having typical anamnesis and complaints should be checked by electroneurography in order to permit a quick operation and to prevent incurable damages of the nerve. The diagnosis leading to operation of the elbow should however be made with greatest care. In case the operation is unavoidable, the ulnar nerve should be thoroughly checked and anterior transposition should be carried out.  相似文献   

19.
20.
The Epstein-Barr virus is a ubiquitous human herpesvirus that is associated with an increasing number of human malignancies. Among these are Epstein-Barr virus-associated lymphoproliferative diseases in immunocompromised patients, a spectrum of mainly B-cell diseases that range from polyclonal lymphoproliferative diseases, which resolve when immunosuppression is halted, to highly malignant lymphomas. Progress has identified Epstein-Barr virus gene products involved in B-cell transformation, variation in Epstein-Barr virus transforming genes, distinct target cell populations with differing regulation of Epstein-Barr virus expression, and selective recruitment of other supportive cell types as factors in the heterogeneity of lymphoproliferative diseases. New therapeutic approaches to treat lymphoproliferative diseases are also being developed. Finally, xenotransplantation poses new risks for the introduction of Epstein-Barr virus-like viruses and more aggressive lymphoproliferative diseases in heavily immunosuppressed patients.  相似文献   

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