Biomedical subjects

R Menapace

Publications and source records attributed to R Menapace.

At least 91 records · Page 5Linked to original sources

PubMed1993

Choroidal melanomas near the optic disk or macula. Long-term results after proton beam irradiation: a report of 3 cases.

Three patients with choroidal melanomas of the posterior pole were treated with proton beam irradiation. One tumor was medium-sized, two were large-sized. Two of the three eyes were functionally single eyes. 60 CGE (cobalt gray equivalents) was delivered in 4 equal treatments during 4 consecutive days. The minimum follow-up period for each patients is 4 years, the average time 4.8 years. Functionally, we lost both eyes with the large-sized tumors owing to severe radiogenic side effects; the eye containing the largest tumor had to be enucleated after 48 months because of phthisis bulbi. No metastases have developed up to now.

Adult↗

PubMed1993

A warm-water perfusion plaque for hyperthermic treatment of intraocular tumors.

This paper describes the design and performance of a plaque aimed at delivering hot-water hyperthermia to intraocular tumors. The plaque transfers heat into the tissues via conduction. Maximum temperature cannot exceed inflow water temperature. The high water flow rate provided by the hyperthermia unit guarantees an excessive power output at a constant temperature level, resulting in a homogeneous temperature distribution in the tissue. Heat distribution over the plaque surface was shown to be uniform. System performance has been studied on enucleated human as well as on living rabbit eyes. Thermal mapping was done in two and one planes, respectively, and the spatial distribution was calculated. Results promise therapeutic temperature levels to a depth exceeding 10 mm.

Animals↗

PubMed1993

Combined local excision and brachytherapy with ruthenium-106 in the treatment of epibulbar malignancies.

Two patients with epibulbar malignancies were treated by local excision and brachytherapy with ruthenium-106. One patient showed a large melanoma on the epibulbar conjunctiva, the other patient suffered from a recurrent squamous cell carcinoma at the limbus. After excision of the tumor including lamellar sclerectomy and keratectomy, a ruthenium-106 plaque was sutured to the sclera, and a total dose of 290 and 320 Gy, respectively, was delivered to the tumor bed. No severe radiogenic complications were observed except for a rarefaction of the sclera in the treatment area and a slow cataract increase. After a follow-up period of 50 and 22 months, respectively, both patients do not show any recurrence or metastatic disease.

Aged↗

PubMed1992

Effect of carbachol on intraocular pressure in small-incision cataract surgery.

Sixty patients, who underwent phacoemulsification and implantation of a folded polyHema intraocular lens were assigned to two groups. Following wound closure 0.5 ml of 0.01% carbachol or balanced salt solution was instilled into the anterior chamber. Healon was used in all eyes but evacuated from the capsular bag behind the intraocular lens and the anterior chamber. Intraocular pressure was measured the day before as well as 6 and 18 hours postoperatively. At 6 hours the mean change of intraocular pressure from baseline was -2.8 +/- 5.3 mmHg in the carbachol group compared with +4.7 +/- 8.0 mmHg in the BSS group (p < 0.0001). At 18 hours the mean change from baseline was -3.0 +/- 4.6 mmHg in the treatment group and +2.3 +/- 8.5 in the control group (p < 0.0001). Intraocular pressure exceeding 25 mmHg at 6 hours was observed in 8 (27%) eyes of the control group but none of the treatment group. At 18 hours 4 (13%) eyes of the control group and 1 (3%) of the carbachol group still had an increase of intraocular pressure. Summarizing our results we conclude that the effect of Healon on the postoperative intraocular pressure is successfully counteracted by its aspiration from the capsular bag and the anterior chamber, especially when carbachol is used for intraoperative miosis.

Aged↗

PubMed1992

Induced astigmatism following small incision cataract surgery combined with trabeculectomy.

The combination of phacoemulsification and implantation of foldable intraocular lenses through a small incision with a trabeculectomy is increasingly preferred in glaucoma patients with coexisting cataract. Small incisions induce less astigmatism and thereby enhance visual recovery. This study should clarify if this benefit of small incision cataract surgery is preserved when combined with a trabeculectomy. Thirty-five eyes were included in this study. Preoperative astigmatism measurements were compared with those obtained one month and one year postoperatively. Vector analysis was performed. A series of 30 cases which underwent small incision cataract surgery alone were used as a control group. One month postoperatively the eyes undergoing the combined procedure showed about the same with-the-rule astigmatic peak (mean: +0.32 dpt.) as the control group eyes (mean: +0.26 dpt.; p > 0.05). One year postoperatively both groups showed the same against-the-rule astigmatic shift (mean: -0.28 dpt.; p > 0.05). In conclusion, patients undergoing small incision cataract surgery combined with trabeculectomy showed a small amount of surgically induced astigmatism. When compared with patients which underwent small incision cataract surgery alone, the difference in astigmatic changes was found to be statistically not significant.

Astigmatism↗

PubMed1992

Endothelial cell density and corneal pachometry after no-stitch, small-incision cataract surgery.

In a prospective study we used the change of central and peripheral (12 o'clock-position) corneal thickness (CT) after no-stitch small incision cataract surgery as a parameter of tissue traumatisation (33 eyes) and compared the values to a series of cases (32 eyes) with conventional 3.5 mm scleral step incision. In both groups the peripheral measurements showed a higher increase in corneal thickness than the central. After 1 month all eyes regained their central preoperative thickness. Increase in corneal thickness (delta CTc, delta CTp) after the different postoperative periods were correlated. The values of the central cornea showed no significant difference between the two groups. 1, 7 and 30 days after surgery the increase of peripheral CT was significantly higher in the no-stitch group. This fact was underlined by the clinical aspect at the slit lamp and is due to the anatomical and surgical characteristic of this procedure. One month postoperatively there was no increased endothelial cell loss in the no-stitch group (3%). No-stitch cataract surgery surgery provides a lot of intra- and postoperative advantages. The problem of increased swelling of the peripheral corneal entry seems to be a secondary one as corneal thickness decreases with time. Concerning the prospective endothelial cell loss it is mandatory to study the long term results.

Aged↗

PubMed1992

Combined small-incision cataract surgery and trabeculectomy--technique and results.

In a prospective study 35 eyes of 25 patients with coexisting cataract and glaucoma underwent trabeculectomy, phacoemulsification and implantation of a folded polyHema intraocular lens through the trabeculectomy opening. Follow-up ranged from 6 to 27 months (mean 13.3). The mean age was 76.4 (68 to 88 years). 22 eyes suffered from primary open angle glaucoma, 10 eyes from a pseudoexfoliation glaucoma and 3 eyes had a chronic angle closure glaucoma. Preoperatively intraocular pressure was controlled in 10 eyes with a mean medication of 2.1 but uncontrolled in 25 eyes (mean medication: 2.5). The preoperative visual acuity ranged from 20/40 to hand motions. Postoperatively intraocular pressure was controlled (< 18 mmHg) in all (100%) eyes and without therapy in 32 (91%) eyes. Three (9%) eyes had to be treated with topical timolol twice a day after surgery. Mean intraocular pressure dropped from 21.2 +/- 6.0 mmHg preoperatively to 13.5 +/- 2.1 mmHg postoperatively. Vision improved in all but 4 eyes, 25 (74%) achieving a visual acuity of 20/40 or better. The causes for failed improvement or deterioration of vision were senile macular degeneration in 2 eyes and central retinal vein occlusion and vascular optic nerve atrophy in one eye respectively. Post-operative complications included hyphema in 9 (26%) eyes, fibrin effusion to a various extent into the anterior chamber in 19 (54%) eyes and delayed hypotony (< 5 mmHg) with chorioidal effusion in 1 (3%) eye. Fibrin effusion was frequently observed in eyes with intraocular pressure below 10 mmHg, iris surgery and hyphema. Finally the complications did not effect the results regarding visual acuity or glaucoma control.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

PubMed1992

Intraocular pressure following small-incision cataract surgery and polyHEMA posterior chamber lens implantation. A comparison between acetylcholine and carbachol.

Ninety patients who had phacoemulsification and implantation of a flexible polyHEMA intraocular lens (IOGEL 1103) were assigned to three groups. After evacuation of sodium hyaluronate retrolentally from the capsular bag, 0.5 ml of 1% acetylcholine chloride, 0.01% carbachol, or balanced salt solution was instilled into the anterior chamber following wound closure. Intraocular pressure (IOP) was measured the day before, and six hours, 18 hours, and one week postoperatively. No topical or systemic antiglaucomatous drug was given during the study period. Preoperatively and one week postoperatively there was no significant difference between the three groups (P greater than .01). At six hours postoperatively the mean IOP decreased in the carbachol group (-2.8 mm Hg) and increased in the acetylcholine and control groups (+0.6 mm Hg and +/- 4.7 mm Hg) when compared with baseline pressures. At 18 hours the mean change from baseline was -3.0 mm Hg in the carbachol group, +0.8 mm Hg in the acetylcholine group, and +2.3 mm Hg in the control group. At six hours IOP exceeding 22 mm Hg was observed in ten of the control patients (30%) receiving balanced salt solution intracamerally and four of the acetylcholine patients (13.3%) but none of the carbachol patients. At 18 hours IOP remained above 22 mm Hg in three of the acetylcholine patients (10%) and four of the control patients (13.3%). Only one of the carbachol patients developed an increase of IOP up to 26 mm Hg at 18 hours. Removal of viscoelastic substances from behind the IOL reduced the incidence of pressure spikes in the early postoperative period.(ABSTRACT TRUNCATED AT 250 WORDS)

Acetylcholine↗

PubMed1992

Evaluation of 200 consecutive IOGEL 1103 capsular-bag lenses implanted through a small incision.

We evaluated 200 consecutive IOGEL 1103 capsular bag intraocular lenses. We performed a 5 to 6 mm capsulorhexis and inserted the intraocular lens (IOL) through a 3.5 to 4.0 mm scleral tunnel with a Faulkner folder. Twenty-two cases were combined with trabeculectomy and ten with keratoplasty using a temporary keratoprosthesis. Mean follow-up was six months. The implant centered well and resisted capsular shrinkage. Iris touch to the optic was rare and did not provoke persistent pigment dispersion. In one third of the cases a cleft was discernible between the posterior convex IOL surface and the extended capsule despite thorough aspiration of viscoelastic and debris from the retrolental space. In 8% of cases, white flakes of unknown origin were observed at the IOL-capsule interface. In cases associated with pre-existing iritis or intraoperative iris trauma (iris manipulation, iridectomy, or synechiolysis in glaucoma patients), fibrin exudation as well as iridocapsular synechial formation and macrophage precipitation often ensued. Cellular precipitates, as evaluated by biomicroscopy and specular microscopy, were less pronounced and more transient than on poly(methyl methacrylate) IOLs. Best case visual acuity results were comparable to those with conventional implants; all eyes attained 20/40 or better and 97% achieved 20/25 or better. The 1103 was easier to implant through a capsulorhexis opening and suited the dimensions of the capsular bag better than the PC-12 model.

Aged↗

PubMed1992

[Evaluating biological tolerance of PMMA, heparin-modified PMMA and hydrogel intraocular lenses using slit lamp microscopy].

In order to find a difference in the biocompatibility of different IOL-materials we examined the lens-surface of poly(methylmetacrylate)-(PMMA-), heparin surface-modified PMMA-(HSM-PMMA-) and hydrogel-IOLs in a prospective study by specular microscopy. Documentation consisted of cellular reaction, precipitates on the lens-surface and irregularities of the IOL-material. Early postoperative on HSM-PMMA and hydrogel-IOLs there were fewer fibroblast-like cells as compared to PMMA-IOLs. In the later postoperative period foreign body giant cells were seen on PMMA-IOLs in 26.6%, on HSM-PMMA and hydrogel-IOLs in less than 10% of the cases. In cases with increased postoperative inflammation or contact between uveal tissue and lens-surface we found more cells and in a higher percentage. Concerning precipitates on the surface and material irregularities we also found lens-specific differences. Clinical results were satisfactory for all lens-types.

Aged↗

PubMed1992

[Effect of intraocular administration of acetylcholine and carbachol on postoperative intraocular pressure after cataract surgery].

In a consecutive series of 90 patients we examined the effect of intracameral acetylcholine and carbachol on intraocular pressure following extracapsular cataract surgery. In all cases phacoemulsification and implantation of a folded polyhema intraocular lens under healon was performed. After evacuation of the viscoelastic substance from the capsular bag behind the inserted lens and wound suturing we instilled 0.5 ml 1% acetylcholine, 0.5 ml 0.01% carbachol or 0.5 ml balanced salt solution respectively into the anterior chamber. Without the influence of antiglaucomatous drugs applanation tonometry was performed 6 and 18 hours postoperatively. When compared with preoperative values intraocular pressure decreased in the carbachol group (-2.8 mm Hg) but increased in the acetylcholine group (+0.6 mm Hg) and control group (+4.7 mm Hg). 18 hours postoperatively the mean change was -3.0 mm Hg in the carbachol group, +0.8 mm Hg in the acetylcholine group and +2.3 mm Hg in the control group. Intraocular pressure exceeding 22 mm Hg at 6 hours was observed in 33% of the control group and 13% of the acetylcholine group but none of the carbachol group. At 18 hours intraocular pressure was still elevated in 13% of the control group, 10% of the acetylcholine group and 3% of the carbachol group. Reviewing our results we conclude that the evacuation of viscoelastic substances from the capsular bag behind the implanted lens reduces the incidence of pressure rises in the early postoperative period. This effect can be enhanced by the use of acetylcholine and, the more potent, carbachol.

Acetylcholine↗

PubMed1992

In vivo observation of surface precipitates of 200 consecutive hydrogel intraocular lenses.

Over a 1.5-year postoperative period, surface precipitates were observed on hydrogel intraocular lenses (IOLs) by specular microscopy. In eyes with prolonged postoperative inflammation, a higher number of cells was observed. In these cases, the cells remained on the IOL surface for a longer period. We found very few small round cells and fibroblast-like cells on hydrogel IOLs during the postoperative period of our follow-up. Only in 8% (16 eyes) foreign-body giant cells were observed. From these 16 eyes, 81.25% showed an increased postoperative inflammation due to a preexisting inflammatory disposition or increased intraoperative trauma. In eyes, where a glaucoma or a corneal triple procedure was performed, foreign-body giant cells were seen in 27.3 or 10%, respectively. Fifty percent of these 16 eyes showed postoperative iridocapsular synechiae. These data show that an increased postoperative inflammation or iridocapsular synechiae cause cell reaction in most of the cases. Excluding all these cases, foreign-body cells were seen in only 1.5% on hydrogel IOLs. These results suggest that p-Hema is a material with high biocompatibility. In 43.5%, we found pigment deposits on the surface of hydrogel IOLs. These pigment granules induced almost no cell reaction with almost no phagocytosis of the pigment debris. In 7% of the cases, dust-like white precipitates of uncertain origin were seen on the IOL surface and posterior capsule; in 5%, amorphous debris was observed. Fine scratches, obviously caused by the polishing process during manufacture, were seen on the hydrogel IOLs.

Aged↗

PubMed1992

Results and implications of high-resolution surface dosimetry of ruthenium-106 eye applicators.

The dosimetry of 106Ru/106Rh beta-emitting eye applicators is still inadequate. Manufacturer's specifications of absolute dose rates are loaded with a +/- 30% error, and the relative distribution of activity on the surface is measured on a few points only, using a 3-mm plastic scintillation probe. While reducing the absolute error of dose rate measurements to +/- 15% by a method published earlier, we now present a phantom using small thermoluminescent dosimetry crystals for refined assessment of its distribution over the surface. Evaluation of two applicators revealed a 50% increase in activity in the midperiphery in one and a steep falloff of activity 1 mm within the margin of both specimens. The method and findings are demonstrated in detail and compared to those reported by other authors.

Brachytherapy↗

PubMed1992

Effect of acetylcholine on intraocular pressure following small-incision cataract surgery.

40 patients, who underwent phacoemulsification and implantation of a polyHema intraocular lens (IOGEL-1103) were assigned to two groups. After evacuation of Healon from the capsular bag behind the lens and the anterior chamber, either 0.5 ml of 1% acetylcholine chloride or 0.5 ml of balanced salt solution was injected into the anterior chamber. When compared with preoperative values, the mean intraocular pressure (IOP) 6 h postoperatively was unchanged in the acetylcholine group (0 +/- 8.5 mm Hg) but increased in the control group (+4.1 +/- 7.4 mm Hg). 18 h postoperatively, the mean intraocular pressure slightly decreased in the acetylcholine group (-0.5 +/- 6.1 mm Hg) compared with an increase of +1.4 +/- 4.4 mm Hg in the control group. Intraocular pressure exceeding 25 mm Hg was observed at 6 h in 2 (10%) patients of the acetylcholine group and in 4 (20%) of the control group. At 18 h, intraocular pressure was elevated in only 1 (5%) patient of the acetylcholine group and in 3 (15%) of the control group. From these results, we conclude that the evacuation of Healon from the capsular bag behind the implanted lens and acetylcholine reduce the incidence of postoperative elevations of intraocular pressure.

Acetylcholine↗

PubMed1992

[Postoperative astigmatism. 3.5 mm scleral tunnel incision and implantation of a HEMA posterior chamber lens vs 7 mm scleral step incision and implantation of a PMMA posterior chamber lens].

In a prospective study, two groups of 35 patients each were compared following phacoemulsification and posterior lens implantation. Both groups were followed up to evaluate the evolution of the postoperative astigmatism during a minimum of 6 months. In group A, a HEMA posterior chamber lens was implanted through a 3.5 mm scleral tunnel incision. In group B, a PMMA posterior chamber lens was implanted through a 7 mm scleral step incision. The data were analyzed for the whole observation time with reference to preoperative, early postoperative, absolute and induced astigmatism. Different subgroups were formed. Vector analysis was performed in both groups in order to determine surgically induced axial changes, e.g., the intensity and direction of the power working on the cornea. The results were compared. Group A showed lesser early postoperative astigmatism than group B; however, group A also returned to the preoperative values more quickly. Both groups exhibited a shift towards against-the-rule astigmatism.

Astigmatism↗

PubMed1992

[Effect of argon laser trabeculoplasty on unrestricted outflow of aqueous humor in eyes with simple glaucoma].

In this prospective study we used the oculopressions-tonometry (OPT) for determination of the aqueous humor outflow facility (C). 53 phacic eyes with glaucoma simplex were examined pre- and postoperatively. One hour after operation C decreased from 0.15 to 0.14. In correlation to this fact the IOD increased. After 7 days C was higher already than preoperatively, 30 days and 6 months after operation C showed normal values. After 6 months the mean decrease in IOD was 5.8 mm Hg, the mean increase in C was 39%. The rate of success after 30 days was 77.4%. IOP and C showed statistically significant changes. The problems with determining C and the causes of the fluctuation of C during our follow-up are discussed.

Adult↗

PubMed1991

Cellular invasion on hydrogel and poly(methyl methacrylate) implants. An in vivo study.

Over a two-year postoperative period, cells on hydrogel (poly HEMA) and poly(methyl methacrylate) (PMMA) intraocular lenses (IOLs) were observed by specular microscopy. First small, round cells and fibroblast-like cells and later epithelioid-like cells and foreign-body giant cells could be seen on both IOL types. In eyes with prolonged postoperative inflammation a greater number of cells was observed and the cells remained on the IOL surface for a longer period. We found fewer cell reactions on hydrogel IOLs during the postoperative period of our follow-up. Foreign-body giant cells were observed on only 9%. These cells were smaller than those on PMMA IOLs. This finding may suggest that poly HEMA demonstrates greater biocompatibility, with regard to this foreign-body cell reaction, than PMMA. However, we found more pigment dispersion (50%) on the surface of hydrogel IOLs. These pigment deposits induced no cell reactions and there was less phagocytosis of the pigment debris. In 7% of the cases, dust-like, white precipitates of uncertain origin were seen; in 5% amorphous debris was seen. Fine scratches caused by polishing during the manufacturing process were seen in some cases. The postoperative clinical signs for PMMA and hydrogel IOLs were similar.

Biocompatible Materials↗

PubMed1991

Results of corneal pachymetry after small-incision hydrogel lens implantation and scleral-step incision poly(methyl methacrylate) lens implantation following phacoemulsification.

In a prospective study we used the change in central and peripheral (12 o'clock position) corneal thickness after two cataract surgery techniques as a parameter of tissue trauma. We looked at whether our findings indicated a difference in corneal thickness in the two groups and thus, as postulated in the literature, in the prospective endothelial cell loss. In 32 eyes (Group A) we performed small incision surgery (3.5 mm to 4.0 mm scleral-step incision) with hydrogel intraocular lenses implanted in the bag. In 30 eyes (Group B) we performed a 7.0 mm scleral-step incision with in-the-bag implantation of conventional poly(methyl methacrylate) intraocular lenses. Increases in corneal thickness (centrally and peripherally) were correlated after different postoperative periods. After 48 hours Group B showed a slightly higher increase in corneal thickness than Group A. Similar findings were observed at five days. In Group B the peripheral thickness did not show as high an increase as the central thickness after 48 hours. In all other cases the peripheral thickness increased more than the central thickness. After one month all eyes regained their preoperative thickness. We did not find a statistically significant difference in central and peripheral corneal thickness between the two groups. The results show that neither of the two surgical techniques greatly influenced the increase in corneal thickness and, consequently, the prospective endothelial cell loss.

Adult↗