Biomedical subjects

C Skorpik

Publications and source records attributed to C Skorpik.

At least 37 records · Page 2Linked to original sources

PubMed1994

Postoperative astigmatism after no-stitch, small incision cataract surgery with 3.5 mm and 4.5 mm incisions.

We studied postoperative astigmatism in 107 patients who were followed for 12 months after phacoemulsification and posterior chamber lens implantation. A scleral incision of 3.5 mm was used in Group A patients and one of 4.5 mm in Group B patients. In both groups a no-stitch wound closure technique was used. A high correlation between preoperative and 12-month postoperative height and time shift of keratometric values was found. In both groups the mean difference was less than 0.60 diopters (D). The mean postoperative cylinder increase was less than 0.50 D; it was less than 0.25 D after six months. The induced astigmatism was confirmed by three different methods. Immediately after surgery, a negative induced astigmatism was found in both groups. After 12 months, induced astigmatism in Group A was -0.37 D and in Group B, -0.67 D. Immediately after surgery there was an axis change; a decrease of with-the-rule astigmatism occurred concurrently with an increase toward oblique and against-the-rule astigmatism. This axis change was somewhat evident after 12 months.

Astigmatism↗

PubMed1994

[Long-term results of implantation of a plate haptic silicone lens in the capsular sac].

BACKGROUND: An important step in developing cataract surgery was the introduction of soft foldable silicone intraocular lenses in the middle 80's. Functional and morphological long-term data are a vital base for definite conclusions on the new material's safety and biocompatibility. PATIENTS AND METHODS: Our study presents the long-term results after the implantation of a silicone posterior chamber lens with solid plate haptic design (STAAR AA-4203). All lenses were folded and implanted through a 4-mm small corneoscleral incision. Our study includes 54 eyes in 52 patients with a mean follow-up period of 56.5 +/- 8.9 months. RESULTS: A visual acuity of 20/40 or better was found in 90.7% of all eyes. All except one of the 33 eyes without any further preexisting ocular pathology at the time of the operation achieved a visual acuity of 20/40 or better. Two thirds of all eyes had a horizontal astigmatism of +1.0 D or less. By slitlamp examination more or less dispersed pigment was seen on the IOL's surface in 46.3%. 83% of the silicone lenses were centrated within 0.5 mm. A YAG-laser capsulotomy was performed in 7 cases (13%). IOL-related intraocular inflammations, cystoid macular edema or an elevated intraocular pressure did not occur in this group. CONCLUSIONS: Our satisfactory long-term results suggest an excellent biocompatibility of the IOL's design and material.

Aged↗

PubMed1993

[Experiences with disc lenses composed of silicone].

Our study presents the results with a silicone disc-lens (Adatomed 90D) over a postoperative period of 18 months. It includes 47 patients, 42 could be reexamined. The implantation was done after continuous circular capsulorhexis and phacoemulsification with a Faulkner-folder directly into the capsular bag. The implantation was sometimes difficult. Skill and experience of the surgeon are required. The IOL springs forth of the implantation forceps, which can lead to traumatization of the capsule and the iris. Three times the posterior capsule ruptured, in two cases the implantation was stopped because of vitreous pressure and the risk of rupturing the capsule. In 6 cases the rim of the anterior capsule ruptured during the implantation. Postoperatively one IOL had a sulcus position, all other IOLs were in the capsular bag. A deposit of viscoelastic substance (Healon) between the IOL and the posterior capsule in 34 cases (72%) was remarkable. In 14 cases (33%) it remained for 18 months. 16 times (38%) regeneratory after-cataract reached the central part of the capsule. The visual disturbance was different, in 6 cases (14%) a YAG-laser-capsulotomy was performed. An influence of the deposit of viscoelastic substance on the development of posterior capsule opacification could not be proved. 17 IOLs (40%) were minimally decentrated upwards. Only 11 cases (26%) had an excellent mydriatic pupillary reaction. The reason is not clear. 10 eyes (24%) developed iridocapsular synechia, 22 eyes (52%) foreign body giant cells and 20 eyes (48%) dispersed pigment on the IOL surface. The giant cells did not diminish.(ABSTRACT TRUNCATED AT 250 WORDS)

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PubMed1990

Optical resolution of foldable intraocular lenses.

Recently manufactured intraocular lenses (IOLs) (STAAR AA 4203 made of silicone and IOGEL PC-12 made of polyHEMA) were tested before and after implantation simulation for axial optical resolution (model eye), for optical surface quality (photokeratoscope), and for surface microtrauma (scanning electron microscopy). At a 3 mm pupillary opening, both lens types achieved a mean axial resolution of 1.25 (range 1.0 to 1.5) on an optotype analogous resolution target. When the pupillary opening was increased to 6 mm, polymacon IOLs showed only a moderate resolution decrease (up to one line) and loss of contrast (up to 30%); silicone IOLs showed almost no decrease. Photokeratoscopic evaluation revealed that a circular optical nonhomogeneity at the peripheral optical zone of the hydrogel IOLs is the source of this impairment. Groove-like surface deformities occasionally observed by scanning electron microscopy did not detectably decrease resolution or contrast.

Humans↗

PubMed1990

Modified triple procedure using a temporary keratoprosthesis for closed-system, small-incision cataract surgery.

In patients with corneal disease and cataract, the combined surgical approach yields quick rehabilitation and excellent visual results. Working on an open eye for cataract removal and posterior chamber lens implantation, however, makes the procedure risky and difficult. Using a temporary keratoprosthesis and a small-incision technique, surgery can be performed in a fully closed system, optimizing the safety and precision of the procedure.

Aged↗

PubMed1990

Evaluation of 150 consecutive cases of poly HEMA posterior chamber lenses implanted in the bag using a small-incision technique.

We report the results of 150 capsular bag implantations of the IOGEL PC-12 hydrogel lens. Mean follow-up was seven months. Following capsulorhexis and phacoemulsification, a Faulkner folder was used to insert the lens through a 3.5 mm to 4.0 mm scleral tunnel incision. Initially, a number of surgical complications were encountered. Because of increasing experience and modified instrumentation and technique, these did not occur in the later cases. Visual results were good, all eyes gaining a best case visual acuity of 20/40 or better and 97% achieving 20/25 or better. Morphological results were satisfactory. Generally the lenses remained centered and at a distance from the iris. Retention of viscoelastic substance or debris between the lens and the posterior capsule, occasionally observed at the start of the series, has been avoided by retrolental aspiration. Persistent pigment dispersion, which was observed when the lens had been implanted in the sulcus, was not seen. Tolerance of the lens material was generally satisfactory. There were six cases (4%) of fibrinoid uveitis, which is a relatively high incidence. From our experience and results we conclude that this implantation procedure allowed controlled insertion and placement of the IOGEL lens, provided that adequate instrumentation and technique was used; visual performance was comparable to that of poly(methyl methacrylate) lenses; capsular bag fixation furnished satisfactory morphological results, provided an adequately shaped capsulorhexis was performed.

Aged↗

PubMed1990

Long-term follow-up of argon laser trabeculoplasty in uncontrolled primary open-angle glaucoma. A study with standardized extensive preoperative treatment.

The long-term results of 180 degrees argon laser trabeculoplasty (ALT) were studied in 61 eyes of 43 patients with uncontrolled primary open-angle glaucoma [intraocular pressure (IOP) less than 22 mm Hg]. In order to enhance the relevance of this prospective study, only eyes that had not responded to medication despite standardized extensive therapy were followed up over an average period of 4.4 years [52.8 +/- 7.3 (mean +/- SD) months]. The success rate of treatment (decrease in IOP less than 5 mm Hg, IOP below 20 mm Hg, stable visual field, stable optic nerve head and no further laser or surgical intervention) after 4.4 years was 73.7%. The mean decrease in IOP was 8.5 +/- 2.9 mm Hg (mean +/- SD). Eyes receiving ALT before cataract surgery retained control of IOP after surgery. A comparable pressure control was also attained with those eyes that had undergone previous trabeculectomy. Failures (26.3%) all occurred in the 1st year after treatment. The results and conclusions from our study are compared with those reported in the literature. The different theories regarding the mechanisms of action of ALT are discussed.

Adult↗

PubMed1990

[Artificial intraocular lenses].

Nowadays the "method of choice" is to implant posterior chamber lenses after ECCE or phacoemulsification, but in the literature excellent results have also been reported with ICCE and anterior chamber lens implantation. To date, however, there have been no statistical data available in which these methods have been compared in a fair way. The best anterior chamber lenses seem to be semiflexible monoblock PMMA lenses with open loops (multiflex style). There should not be too much difference between the diameter of the IOL and the diameter of the anterior chamber. Rigid anterior chamber lenses (Choyce style) must be fitted very precisely to avoid complications. Lenses with closed loops (e.g., stable flex) have a very high complication rate and this implantation procedure should be discontinued. Lenses with inserted flexible open loops (e.g., Dubroff) have only been implanted in small series, but the results have been quite good. Follow-up investigations will show what the quality of this type of lens really is. Posterior chamber lenses are mostly implanted into the capsular sac. Only in special cases is sulcus implantation performed; the lens material is mostly PMMA. The loops are also made of PMMA and only rarely of prolene. There is a trend to implant "one-piece lenses"--the optic and haptic are cut out of one piece of PMMA. The rigidity of the loops and the loop configuration are important for centering the IOL and the stability in the sulcus or in the capsular sac. Mainly modified C-loops (Simcoe style) are used. With symmetric, complete capsular sac fixation, the results are very satisfactory.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMed1989

Comparison of contrast sensitivity between posterior chamber lenses of silicone and PMMA material.

Seventeen patients received a posterior chamber lens of PMMA in one eye and a silicone lens (Staar Surgical Co.) in the other. Contrast sensitivity was examined in both eyes in order to detect differences with respect to the material used for lens implantation. An attempt was made to exclude any changes in the eyes that were not due to lens implantation and that might possibly have an influence on the result. A paired T-test was performed for each spatial frequency. No statistically significant difference was found between the two materials with regard to contrast sensitivity.

Aged↗

PubMed1989

Evaluation of the first 60 cases of poly HEMA posterior chamber lenses implanted in the sulcus.

Flexible lenses allow folding and inserting through a small incision. Using Faulkner's forceps, 60 hydrogel lenses were implanted in the sulcus through a 3.5 mm pocket incision following phacoemulsification. Mean follow-up was six months. The lens was suitable for the procedure when it was properly handled. When it was not, untimely unfolding or tears occurred, necessitating prolonged maneuvering in the eye or sometimes replacement of the lens which caused increased trauma. Though functional results were comparable to those achieved with polymethylmethacrylate lenses, all eyes achieving a visual acuity of 20/40 or better, morphological results were less satisfactory. Because of hydrogel's lack of adhesiveness and the inability to estimate the individual sulcus diameter, pseudophakodonesis was a common observation. The lens touching the posterior iris surface caused pigment dispersion (37%), sometimes leading to secondary pigment glaucoma. For this reason, we now favor capsular bag fixation.

Acrylates↗

PubMed1989

Tissue reaction after silicone and poly(methyl methacrylate) intraocular lens implantation: a light and electron microscopy study in a rabbit model.

We describe the histopathologic results of extracapsular lens extraction and silicone and poly(methyl methacrylate) (PMMA) intraocular lens (IOL) implantation in 36 rabbit eyes. Phase-contrast microscopy was used to examine precipitates on IOL surfaces and posterior capsules. Semithin and ultrathin sections were taken from the central cornea, anterior uvea, capsular bag, and retina near the posterior pole. The follow-up was one to 16 weeks. Silicone IOLs did not cause significantly less precipitation than PMMA IOLs. Precipitates consisted of spindle-shaped fibroblast-like cells, various forms of inflammatory cells and multinucleated giant cells, single melanophages, and irregularly arranged birefringent collagen fibers. Corneal endothelial edema was slightly more prominent in PMMA IOL implanted eyes. Significant retinal edema in the posterior pole area was not observed with either of the two lens types. Severe precipitation in the form of large clusters of pigment cells and inflammatory reactions seemed to depend on mechanical trauma (iris capture and lens dislocation) and individual animal reactions, but not on the lens type used.

Animals↗

PubMed1989

[Technic and initial results of capsule sack implantation of hydrogen lenses using a small incision].

Hydrogel lenses are flexible and hydrophilic. The IOGEL lens can be folded with Faulkner forceps and implanted through a 3.5 mm incision. Inadvertant contact with the endothelium causes only minimal cell loss. In April 1988, the authors switched from sulcus to bag fixation and have since inserted 35 lenses. Capsulorhexis appears to guarantee stability and centration. Complications are rare and minor in nature, and can be avoided by adopting an appropriate technique. While retaining all the advantages of phacoemulsification, the procedure considerably accelerates physical and visual rehabilitation. However, long-term results must be awaited.

Aged↗

PubMed1989

Silicone oil implantation in penetrating injuries complicated by PVR. Results from 1982 to 1986.

Between 1982 and 1986, the authors implanted silicone oil in 34 eyes with retinal detachment and proliferative vitreoretinopathy (PVR) stages C-3 to D-3 caused by penetrating injuries. The retina had failed to reattach after initial vitrectomy, membrane peeling, and scleral buckling. Complete anatomic reattachment was achieved in 62%, partial reattachment in an additional 9%. Useful functional results were achieved in 68% of cases (visual acuity of 1/60 to 20/20). Postoperative complications included elevated intraocular pressure in 38% and progress of PVR with membrane formation under the silicone oil in 21% of the cases. Sixty-eight percent of the aphakic eyes developed band-shaped keratopathy. Because most of the eyes were aphakic, the authors do not report cataract incidence. In 15 eyes (44%) the silicone oil was removed. In 14 of these eyes the retina remains attached, in one eye silicone oil removal was followed by phthisis bulbi.

Eye Diseases↗

PubMed1989

Assessment of echographic regression criteria in ruthenium-irradiated melanoma.

Steady flattening of the tumor, increasing reflectivity and decreasing vascularity are echographic signs of successful irradiation treatment. The specific example of an irradiated choroidal melanoma shows that the absence of echographic changes by no means excludes tumor destruction. Because of a dense vitreous body hemorrhage, the melanoma could only be evaluated echographically. Since the echogram lacked evidence of regression, the tumor was locally resected 5 months later. Histology, however, revealed an amorphous mass of dead tissue pervaded by intact vessels. Apparently a successfully irradiated melanoma may generate an echo typical of vital melanoma tissue. The authors therefore draw the conclusion that only a steady tumor growth, as substantiated by an echogram, may be considered an unambiguous sign of tumor vitality.

Choroid Neoplasms↗

PubMed1988

Influence of indomethacin on PGE2 in rabbit aqueous humor after YAG laser photodisruption of the iris.

In an experimental study with rabbits, the influence of indomethacin on the postoperative PGE2 level in the aqueous humor was investigated, following YAG laser traumatization of the iris. Indomethacin is a drug with an inhibitory effect on the synthesis of prostaglandins. Using albino rabbits, the right eye was treated with indomethacin eye drops three times daily for 3 days. On the 4th day, high-energy YAG laser was applied to the iris of both eyes (Q-switched Nd: YAG Laser, Model Cilco Lasertek PV 135; ten photodisruptive lesions, with 50 mJ to the midperiphery of the iris). Subsequently, the rabbits were subdivided into three groups. In group 1 the aqueous humor was removed from both eyes 12 h postoperatively; in group 2 the aqueous humor was tapped 36 h after the intervention; for group 3, it was 60 h afterwards. The results from 15 rabbits were evaluated. Local indomethacin treatment was continued until tapping of the aqueous humor. As a control, another group was used with 3 rabbits without treatment. Twelve hours after YAG laser treatment there was still a clearly significant difference in the PGE2 concentrations between the eyes that had received indomethacin and the untreated eyes; 36 h postoperatively, the difference was no longer statistically significant, and after 60 h the PGE2 concentrations of the treated and untreated eyes were the same.

Animals↗

PubMed1988

[Comparison of the effectiveness and safety of levobunolol and timolol in ocular hypertension and chronic open-angle glaucoma].

Twenty-six patients with open-angle glaucoma or ocular hypertension were studied in a concomitant double-masked clinical trial lasting three months, in which the ocular hypotensive efficacy and safety of levobunolol (0.5%) and timolol (0.5%), topically administered twice daily, were compared. At all follow-up examinations there was a significant decrease in mean intraocular pressure from baseline in both treatment groups, with no significant difference between them in this regard. Few changes were seen in either treatment group in cup/disk ratio, visual fields, visual acuity, biomicroscopy, or ophthalmoscopy. In both groups slight decreases in mean blood pressure were observed. Levobunolol and timolol were similarly effective and safe in reducing intraocular pressure in patients with chronic open-angle glaucoma and those with ocular hypertension.

Adult↗

PubMed1988

The triple procedure--results in cataract patients with corneal opacity.

Beginning in May 1984, we performed penetrating keratoplasties in combination with extracapsular cataract extractions and implantations of posterior chamber lenses in 21 patients. In addition to cataracts, 15 of these elderly patients presented Fuchs' dystrophy and 6 had corneal scars due to infectious or inflammatory corneal diseases. In 2 of the 21 eyes, keratoplasty was a repeat operation because of graft rejection or graft dystrophy. With a mean follow-up of 22 months, visual rehabilitation was satisfactory: 15 patients (71%) achieved a postoperative corrected visual acuity of 6/12 or better. Postoperative deviation from preoperatively calculated refractive lens power--the only major problem--remained within +/- 2 dptr in 95% (20 eyes), with an error of + 4 dptr in 1 eye (5%). In all 21 eyes, clear corneal grafts were obtained. Thus we consider the triple procedure to be the treatment of choice in cataract patients with corneas opacities.

Aged↗

PubMed1987

Effect of indomethacin on aqueous PGE2 levels in rabbits following ocular trauma.

Using a highly specific radioimmunoassay, post-traumatic aqueous PGE2 levels were measured in rabbit eyes treated with topical indomethacin aqueous solution, as well as in untreated eyes. In two groups of ten rabbits each, the surgical trauma consisted of corneoscleral incision (without injury to the iris); one of the two groups received prophylactic treatment (3 days) and therapeutic (21 days) indomethacin treatment. In two other groups of ten rabbits each, corneoscleral incision and iridectomy were performed. One group received indomethacin treatment as described above, while the other group was not treated. Surgery was performed in all 40 right eyes, the left eyes serving as controls. In 20 of the 40 left eyes, indomethacin therapy was applied. In all right and left eyes, aqueous samples were withdrawn 3 days and 21 days postoperatively, and PGE2 concentrations were determined. The results indicate that 3 days after corneal trauma and 3 days after corneal trauma plus iridectomy, there was a highly significant reduction in the elevated PGE2 concentrations as a result of indomethacin therapy. On postoperative day 21, indomethacin reduced even further the still slightly elevated aqueous PGE2 concentrations without, however, completely blocking prostaglandin activity. The latter was observed even in the control animals that were not operated upon; they showed minimal PGE2 levels in response to corneal puncture on postoperative day 3 for the purpose of drawing aqueous samples. Our study demonstrated that short-term indomethacin therapy has a significant inhibitory effect, but no unequivocal answers were found as to the value of long-term treatment.

Animals↗