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P Kroll

Publications and source records attributed to P Kroll.

At least 37 records · Page 2Linked to original sources
PubMed2000

[Vitreoretinal surgery in complicated retinal detachment in children and adolescents].

BACKGROUND: The purpose of this study was to evaluate anatomical and functional results of vitreoretinal silicone oil surgery for complicated retinal detachments due to trauma and myopia in children and juveniles. METHODS: We retrospectively reviewed the records of children and juveniles up to 17 years of age who had undergone vitreoretinal surgery with silicone oil instillation for the above causes between 1990 and 1997. A total of 30 eyes of 29 patients were operated on, 24 because of trauma and the remaining 6 because of retinal detachment in high myopia. There was a mean postoperative follow-up period of 1.7 years. Silicone oil could be removed from 18 of the 30 eyes after a mean of 4.7 months. The median number of vitrectomies performed per eye was two (range one to five). RESULTS: In 21 of 30 eyes (70%) the retina could be reattached after one or more surgeries. Silicone oil was removed from 16 of these 21 eyes (53%) which was defined as anatomical success. Visual acuity increased (14 eyes, 48.3%) or remained unchanged (9 eyes, 31%) in 23 of 29 eyes (79.3%). Visual acuity decreased in 6 of 29 eyes (20.7%) despite surgery. Two eyes (6.7%) had to be enucleated due to bulbar phthisis. Seventeen eyes reached a postoperative visual acuity of at least counting fingers. In one child functional tests could not be performed due to young age. CONCLUSION: Vitreoretinal surgery with silicone oil endotamponade has become a standard procedure in treating complicated retinal pathologies in children and juveniles. In very young patients it is thought that silicone oil instillation has advantages over gas endotamponade since it is very difficult for children to keep the proper face-down positioning after the procedure. The retinal reattachment rate is encouraging. In the majority of cases visual acuity greater than or equal to counting fingers and thus orienting vision was reached postoperatively. In few cases even reading vision was regained.

Adolescent↗
PubMed2000

[Air endotamponade in 52 vitrectomies due to proliferative diabetic retinopathy--retrospective comparison with 40 vitrectomies without endotamponade].

BACKGROUND: In patients with proliferative diabetic retinopathy rebleeding after pars plana vitrectomy is one of the most common complications. We tried to reduce the rate of that complication by using an air endotamponade. PATIENTS AND METHODS: The following study is a retrospective comparison of 2 patient groups both after pars plana vitrectomy due to proliferative diabetic retinopathy. Group 1 was managed with air as endotamponade (n = 52, mean age 61.2 years), group 2 without any endotamponade (n = 40, mean age 59.4 years). Classification of the proliferative diabetic retinopathy as described by Kroll et al. [5] in both groups: 23 and 29 patients with stage A resp., 24 and 10 patients with stage B resp., 5 and 1 patient with stage C respectively. RESULTS: 77% of group 1 patients had an increase os vision by mean of 4.8 vision steps, in 70% of the group 2 patients vision increased by mean of 7.2 vision steps. Complications in both groups as follows: Rebleeding within 14 days 15% vs. 33%, development of secondary glaucoma in 9.6% and 17.5% resp., revitrectomy within 14 days were necessary in 3.8% resp. 2.5% of the patients, later revitrectomy in 13.5% vs. 42.5% of all patients. SUMMARY: Air endotamponade turned out to be appropriate to reduce the rate of postoperative vitreous rebleeding after pars plana vitrectomy due to proliferative diabetic retinopathy. We found no increase of secondary glaucoma or cataract.

Adult↗
PubMed2000

Quantitative effect of intravitreally injected tissue plasminogen activator and gas on subretinal hemorrhage.

PURPOSE: To quantify the effect of intravitreally injected tissue plasminogen activator (TPA) and an expanding gas on freshly formed subretinal hemorrhage (SRH). PATIENTS AND METHODS: Thirteen patients with acute (1 week or less) SRH due to age-related macular degeneration (ARMD) were treated with an intravitreal injection of 50 microg TPA, and 24 hours later, with an expanding gas. Fundus photographs taken before and 24 hours after each injection were digitized and calibrated. Area, geometric center, and shift of the SRH were measured at each time point using NIH image analysis software. Elevation of the SRH was assessed by echography. RESULTS: Compared to the preoperative size, SRH enlarged significantly 24 hours after TPA injection (P < 0.001). A significant shift of the geometric center toward the inferior retinal periphery out of the macula was found after gas injection (P < 0.001). Significant horizontal displacement of the SRH was not noted after TPA or gas injection. More elevated subretinal blood clots showed a larger increase in size after TPA injection than flat clots (P < 0.05). CONCLUSION: Enlargement of SRH in a gravity-dependent manner indicates subretinal liquefaction of the clot after TPA treatment. An intravitreal injection of gas 24 hours later can significantly displace the SRH inferiorly.

Acute Disease↗
PubMed2000

Pigment epithelium defects after submacular surgery for choroidal neovascularization: first results.

It was the aim of this study to compare postoperative pigment epithelium defects after submacular surgery for well-defined choroidal neovascularization (CNV) with preoperative fluorescein angiogram (FAG), indocyanine green angiogram (ICG), and intraoperative findings of the excised neovacularization. Surgical removal of the CNV was videotaped. By means of a gauge the absolute size of an anatomic structure was determined which was visible on video, FAG, and ICG as well. Postoperatively another FAG was performed to further examine the funduscopically visible pigment epithelium defect. By comparison with the above-mentioned anatomic structure it was thus possible to determine the exact size of CNV and pigment epithelium defect. The extent of the pigment epithelium defect as determined on postoperative FAG after submacular surgery surpasses the size of CNV as measured in FAG, ICG, and anatomical preparation.

Adult↗
PubMed1999

[Exudative retinal detachment surgery. A prognostic++ parameter of malignant melanoma in brachytherapy?].

BACKGROUND: The purpose of this study was to compare the regression of the tumor-distant exudative detachment that accompanies malignant melanoma with regression of the tumor as a result of ruthenium-106 irradiation. METHODS: From 1994 until the beginning of 1996 we treated 28 patients with choroidal malignant melanoma with radioactive plaque therapy. Follow-up examinations were completed 3 and 6 weeks, 3, 6 and 12 months after therapy and finally at 1 year or half-year intervals. Twenty-three patients met the study requirements. RESULTS: Initially, after irradiation there was an increase in the retinal detachment. In 15 patients (65%) we found rapid regression of the detachment, accompanied by distinct tumor regression (61%). One of these patients revealed only minor tumor regression in spite of regression of the exudative detachment. Three months after radiation, 8 patients showed no rapid regression of the exudative detachment. Two of these patients had to undergo a second irradiation and 2 were enucleated because of absent tumor regression. One patient died. Three patients showed an increase in the detachment, accompanied by tumor regression. CONCLUSIONS: Rapid regression of the exudative detachment (> or = 50% of the preoperative detachment) approximately 3 months after irradiation seems to be of good prognostic value for tumor regression.

Adult↗
PubMed1999

Management of acute submacular hemorrhage using recombinant tissue plasminogen activator and gas.

PURPOSE: To assess the effects of intravitreal injection of recombinant tissue plasminogen activator (rTPA) and gas on submacular hemorrhage in age-related macular degeneration (ARMD). METHODS: Eleven consecutive patients (11 eyes) with subretinal hemorrhage due to ARMD involving the fovea with elevation of the neurosensory retina were included in this study. Subretinal hemorrhage occured 12 h to 14 days before onset of therapy. Injection of rTPA through the pars plana in a dose of 50 or 100 microg was performed. Gas instillation (0.2-0.4 ml) followed rTPA injection, either immediately after injection (7 patients) or during the following day (4 patients). RESULTS: After intravitreal injection of rTPA, subretinal clots were totally or partially liquefied when treatment started up to 3 days after onset of bleeding. In all patients treated with 100 microg rTPA a large exudative retinal detachment of the inferior retina resulted, which reabsorbed spontaneously within 2 weeks. After reattachment of the exudative retinal detachment hyperpigmentation of the retinal pigment epithelium was noted. Temporary opacification of the vitreous was observed between the 2nd and 7th postoperative day in 5 eyes (45.5%). Postoperative visual acuity increased in 5 patients (45.5%). CONCLUSION: Intravitreal application of rTPA followed by gas injection is a sufficient and convenient technique for effective removal of freshly formed submacular hemorrhage. Removal is mediated through combined enzymatic (rTPA) and mechanical (gas) effects. This technique offers a quick recovery of vision in eyes with less severe ARMD.

Acute Disease↗
PubMed1999

[Disturbances of binocular vision in macular heterotopia].

BACKGROUND: Tractive translocation of the macula (secondary macular heterotopia) may result in disturbance of binocular vision. The report of a case shall discuss the sensorial problems of these patients. HISTORY AND SIGNS: We report of a 40-years old male who had decreased visual acuity and loss of binocular vision for several years due to episodes of uveitis with intravitreous hemorrhage and cataract formation. After bilateral vitrectomy and cataract extraction a good visual acuity was restored in both eyes. Postoperatively, the patient monocularly complained about disturbed egocentric localization (tilting of the visual environment, "past-pointing") and metamorphopsia. Binocularly he was confused by doubled vision with tilted images. Both maculae showed a tractive translocation of 15 degrees downward. Measurements of binocular alignment with the tangent screen showed an excyclotropia of 8 degrees and an exotropia of 7 degrees in all directions of gaze. Haploscopic examination with fusion images demonstrated that sensorial fusion was not possible even with perfect ocular alignment due to disturbed relative retinal localization (obligate fixation disparity). THERAPY AND OUTCOME: Initially, full time occlusion of the left eye was required. After improvement of symptoms occlusion therapy was slowly tapered. Within one year the patient had learned to suppress the image of his left eye and reported only minor residual visual disturbances even without occlusion of his left eye. CONCLUSIONS: Secondary translocation of the macula monocularly results in a disturbance of egocentric localization and in metamorphopsia. Binocularly doubled vision with tilted images and a loss of sensorial fusion are seen. With monocular vision, perceptual adapting to the aberration in egocentric localisation is possible within weeks by reallocation of the retinal meridians in the central nervous system. Binocular improvement of symptoms is limited to the learning of suppression. Improvement of binocular symptoms by adaptation of retinal correspondence does not occur.

Adult↗
PubMed1999

[Enzymatically induced posterior vitreous detachment in proliferative diabetic vitreoretinopathy].

BACKGROUND: Complete detachment of the posterior vitreous cortex is an important aim in the treatment of proliferative diabetic vitreoretinopathy (PDVR). Today a posterior vitreous detachment (PVD) can only be achieved during vitrectomy. A randomized pilot study was started to evaluate wether intravitreally injected TPA is sufficient to induce a PVD in diabetic eyes. PATIENTS AND METHODS: Eight weeks prior to vitrectomy because of proliferative diabetic vitreoretinopathy (non-clearing haemorrhage, fibrovascular proliferations) 20 eyes which had an attached vitreous received a cryopexy of the peripheral retina. In 11 eyes that had been selected at random 10 micrograms of recombinant tissue plasminogen activator were injected midvitreally 24 hrs later. A newly formed PVD was assessed by means of biomicroscopy or ultrasound. RESULTS: A newly formed partial (n = 3) or complete (n = 7) PVD was found in 10 of 11 TPA-treated eyes versus one partial detached vitreous in the control group. In 3 younger patients PVD developed exclusively after TPA-injection. We did not observe severe changes of the ERG, decrease of visual acuity, severe new vitreous haemorrhages or opacities of the lens. In 3 eyes (2 eyes of the control group) a circumscribed retinal detachment developed during the follow-up period. CONCLUSIONS: The described technique can be used in diabetics without severe side effects. It facilitates the removal of the vitreous cortex and may be a valuable adjunct to the surgical management of PDVR. Unlike other proteases TPA is available for clinical use through recombinant DNA technology which allows standardized enzymatic activities, steril and non-infectious conditions.

Adult↗
PubMed1999

Vitreopapillary traction in proliferative diabetic vitreoretinopathy [ssee comments].

AIM: To present the clinical profile of a new entity in advanced proliferative diabetic vitreoretinopathy (PDVR). Mechanisms of vision loss due to vitreopapillary traction on the nasal optic disc are described, followed by an introduction of methods for prevention and treatment in such cases. METHODS: 17 patients with PDVR and traction on the nasal side of the optic disc, pallor of the optic nerve head, and reduced visual acuity were included in the study. Six patients were observed retrospectively and 11 patients prospectively before and after pars plana vitrectomy. Pre- and postoperative examinations included visual acuity, Goldmann's visual field, fluorescein angiography, and measurements of visual evoked potentials (VEP). RESULTS: During a postoperative follow up period of 3 to 24.5 months (mean 14.5 months) an improvement in optic disc appearance combined with an increased visual acuity (mean increase in VA = 0.171) was observed in 15/17 (88.3%) patients. In addition, 8/17 (47%) of these patients showed higher VEP amplitudes (mean 3.83 microV), and eight (6/8 of the same patients as VEP amplitudes) patients showed a reduction of latency (mean reduction 22.25 ms) during VEP assessment. CONCLUSION: These results suggest that vitreopapillary traction may damage the anterior optic nerve, via decreased axoplasmatic flow in the optic nerve fibres and/or mechanical reduction of perfusion in the posterior ciliary arteries. The effects of each mechanism appear to be reversible, but in the long term might lead to irreversible optic nerve atrophy. Therefore, in patients with vitreopapillary traction, early vitrectomy should be considered as a method to prevent optic neuropathy.

Adult↗
PubMed1999

Conjunctival malignant melanoma in children.

The first case concerns a 14-year-old girl with a brown conjunctival mass temporally in her right eye which was excised and diagnosed as active conjunctival melanotic lesion. Five years later, a malignant melanoma of the right lacrimal sac and orbit led to general metastatic spread. The second case demonstrates a conjunctival brown mass temporally in the left eye of a 3-year-old boy which enlarged over 4 years. The excision revealed a melanotic lesion which was of uncertain histological dignity. The third case occurred in a 4-year-old boy with a conjunctival glassy tumor temporally in his right eye which after excision led to controversial discussions concerning benign nevus or malignant melanoma.

Adolescent↗
PubMed1998

[External trabecular excision--alternative to filtering glaucoma operation in patients with open angle glaucoma].

BACKGROUND: Postoperative complications concerning glaucoma filtering surgery (trabeculectomy, goniotrepanation) often include hypotonia that may lead to athalamia or choroidal detachment, which are difficult to handle. Cystic non filtering blebs are due to postinflammatory reactions, and may limit the success of filtering surgery. Aim of the study was to compare the success and the complications of a new operating technique, which will be described, with those of usual glaucoma filtering surgery. PATIENTS AND METHODS: In 24 open angle glaucoma patients with mean intraocular pressure of 28.12 mm Hg (+/- 8.6) we performed external trabecular excision in 25 eyes since June 1997. Preoperative visual acuity and peak intraocular pressure were compared retrospectively in all eyes with the values of the first postoperative day, in 22 eyes after one month and in 17 eyes after 3 months. RESULTS: Intraocular pressure measured between 0 mm Hg and 16 mm Hg on the first postoperative day (7.64 mm Hg +/- 4.3), after one month between 10 mm Hg and 30 mm Hg (17.81 mm Hg +/- 5.5) and after 3 months between 9 mm Hg and 26 mm Hg (15.29 mm Hg +/- 4.2). After 1 month 10 of 22 (45%) and after 3 months 7 of 17 eyes (42%) required antiglaucomatous drugs; 3 eyes needed gonitrepanation (2 weeks, 1 month, 3 months after ETE). Concerning postoperative complications, we observed 6 choroidal detachments, once erythrocoytes in the anterior chamber, twice hyphemata, twice inflammatory reaction in the anterior chamber, two flat anterior chambers and twice a positive seidel test. CONCLUSION: Complications after ETE are similar to those after filtering surgery. Postoperative intraocular pressure dip after ETE in most eyes was not as pronounced as after goniotrepanation or trabeculectomy, and postoperative complications were all reversible. 45% of the eyes again needed antiglaucomatous drugs after one month and 42% after 3 months. A prospective long-term study has to verify the success respectively the complications of ETE.

Adult↗
PubMed1998

[Are there indications for abortion or cesarean section and contraindications for spontaneous delivery in ophthalmologic diseases? Case report and overview].

Management of labor and indications for abortion in patients with ophthalmologic diseases are discussed controversially in literature and are often overemphasized. We present a case of a pregnant woman with bilateral papilledema due to pseudotumor cerebri, because an abortion was in question. This case lead us to discuss indications for abortions in patients with pseudotumor cerebri, as well as indications for abortions or cesarean sections in patients with high myopia, retinal detachment, retinopathy in EPH-gestosis, uveal melanoma and diabetic retinopathy. In this article these questions will be discussed.

Abortion, Induced↗
PubMed1998

[Analysis of results after primary heminephrectomy in surgical treatment of duplicated pyelo-caliceal system].

AIM: Determination of the effective diagnostics and therapeutic procedures in duplicated pyelo-calyceal system with upper pole dysfunction. METHOD: Retrospective review of operative procedures and follow-up. MATERIAL: In Department of Pediatric Surgery University of Medical Sciences in Poznań (Poland), 383 children with duplicated pyelo-calyceal system were treated between 1976 and 1997. The diagnosis was based on: IVP, MCU, scintigraphy, cystoscopy, and since 1984 on US. Conservative treatment was performed in 103 (26%) children with low VOR. The most frequent surgical procedure was Politano-Leadbetter ureteroneocystostomy carried out in 167 (44%) children. Primary heminephrectomy was performed in 79 (21%) patients with complete deterioration of the upper pole of the kidney. In order to attain upper pole parenchyma protection in 34 (9%) children the following primary procedures were performed: extirpation of the ureterocele with ureteroneocystostomy of both ureters, cutaneous uretral stoma or uretero-pyeloanastomosis. RESULTS: Among 79 children with primary heminephrectomy of the duplicated system with ureterocele, secondary operation was required only in 18 patients. From 34 children with kidney parenchyma protecting procedures in 18 patients secondary heminephrectomy or nephrectomy was performed. CONCLUSIONS: 1. Primary heminephrectomy with ureterectomy with partial ureterectomy is a method of choice in the treatment of seriously deteriorated upper pole of the duplicated pyelo-calyceal system. 2. Secondary surgical procedures were required only in 25% of children in whom primary heminephrectomy was performed. 3. Primary heminephrectomy is a save procedure with a low complication rate.

Adolescent↗
PubMed1998

[Intravesical instillation of atropine in treatment of detrusor overactivity in children].

UNLABELLED: We present our own experiences with intravesical Atropine instillation in patients with voiding dysfunction. We used concentration of 10(-6) Atropine in 14 patients with detrusor overactivity. In 12 patients neurogenic voiding dysfunction was caused by a meningomyelocoele. In 2 dysfunction was non-neurogenic. Patients were selected on the base of urodynamic investigation in which low bladder cystometric capacity was caused by detrusor overactivity and poor bladder compliance. This type of therapy was started in patients who had not responded to oral oxybutynin therapy, had major side-effects, or oral therapy had not been possible. All were on clean intermittent catheterisation. The effects on the functional parameters were estimated in urodynamic investigations. With the aim of estimating systemic side-effects blood pressure and heart rate was monitored during Atropine infusion. RESULTS: 6 patients responded to intravesical instillation of Atropine. The increase in bladder cystometric capacity was caused by the decrease in bladder overactivity. No effect on bladder wall compliance was noted. No systemic side-effects were observed. CONCLUSIONS: 1. Intravesical Atropine instillation was useful method of treatment in some patients with detrusor overactivity. 2. No systemic side effects were noted. 3. Because of limited effectiveness and low cost, this method should be considered as an alternative way of decreasing bladder overactivity.

Administration, Intravesical↗
PubMed1998

[Electrostimulation in treatment of neurogenic and non-neurogenic voiding dysfunction].

UNLABELLED: The efficiency of transcutaneous and intravesical temporary electrostimulation were evaluated in patients with neurogenic and non-neurogenic voiding dysfunction. Non-invasive electrostimulation was performed in 42 children with voiding dysfunction, at the age of 4 months to 15 years. In 5 children rectal electrode and impulse frequency of 50 Hz was used because of incompetent urethral function. In 9 children with detrusor overactivity rectal electrode and impulse frequency of 5 Hz was used. In 12 girls with discoordinated voiding electrostimulation with rectal electrode was used in biofeedback training. In one case intravesical electrostimulation was used in a girl with lazy bladder syndrome. In 15 patients with neurogenic voiding dysfunction intravesical electrostimulation was used to improve bladder sensation. The efficiency of the treatment was evaluated on the base of urodynamic investigation and patients' observations. The improvement was observed in 3 children from the group with urethral incompetence, both in urodynamic parameters and subjective patients' observations. One girl claimed no change in continence despite improvement in cystometric and profilometric testing. In one girl no change in urodynamic evaluation and continence was observed. Good results were observed in the group of 9 girls in which electrostimulation with rectal electrode was a part of the biofeedback training in discoordinated voiding. In the group of 9 children in whom electrostimulation with rectal electrode was used because of detrusor overactivity in 5 cases improvement in cystometric capacity was estimated. The estimation of usefulness of the intravesical electrostimulation in patients with neurogenic voiding dysfunction is not possible because of too short time of observation and the age of patients. We had to stop stimulation with rectal electrode in one patient because of inflammation of the skin in perineal region caused by cystitis. In two children stimulated with intravesical electrodes a new infection of urinary tract was observed. CONCLUSIONS: 1. Electrostimulation is a non-invasive, save method in the treatment of voiding dysfunction. 2. Electrostimulation with rectal electrodes is an effective method of treatment in cases of urethral incompetence, and an alternative method of treatment for detrusor overactivity. 3. Electrostimulation with rectal electrodes is an additional tool in biofeedback training of discoordinated voiding.

Adolescent↗