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P Kroll

Publications and source records attributed to P Kroll.

At least 55 records · Page 3Linked to original sources
PubMed1998

[Staghorn calculi of the kidney and ureter as a urologic complication ina child with cerebral palsy].

UNLABELLED: We present a child with cerebral palsy, treated for renal and ureteral staghorn calculi. Calculosis was associated with neurogenic voiding dysfunction. CASE REPORT: A 10 year boy was admitted to Pediatric Surgery Clinic in Poznań because of urolithiasis. In neurologic examination four-extremities spastic paresis and convergent strabismus was found. Intellectual contact with this child was very poor. Constant urine leakage from urethra was observed. In urine analysis pH < 7, leucocytes and erythrocytes, in urine culture Proteus vulgaris > 10(5). Ultrasonography revealed three staghorn calculi in right kidney. On the plain x-ray film three calculi in right kidney and two staghorn calculi in right ureter. In urodynamic evaluation in cystometry: low bladder compliance, no detrusor overactivity, no bladder sensation, "leak point" pressure 25-27 cm H2O. In profilometry incompetent urethral closure mechanism. All stones were evacuated during one operation. Postoperative course was uneventful. Risk factors in the treatment of patients with cerebral palsy are stressed. CONCLUSIONS: 1. Dysfunction of lower urinary tract is an important clinical problem in children with cerebral palsy. 2. Voiding dysfunction could be a risk factor in the development of urinary stones. 3. In the treatment of children with cerebral palsy multispecialistic team is needed.

Cerebral Palsy↗
PubMed1998

[The role of psychogenic factors as a cause of urinary retention in a patient with lazy bladder syndrome].

UNLABELLED: We present a child with "Lazy Bladder Syndrome". In this case psychogenic factors appeared to play an important role in the development of the voiding dysfunction in her. This factors influenced also the course of the treatment. CASE REPORT: A 14 years old girl admitted to Paediatric Surgery Clinic in Poznań with urine retention lasting for 20 hours. The child came of the pathologic family, and did not live with its parents. In the anamnesis: irregular mictions with episodes of urine retention. In clinical examination we found only bladder reaching the umbilicus, from which after catheterisation we got 1300 ml of urine. Antibacterial agent and observation was prescribed. After next 12 hours she passed no urine and intermittent catheterisation was started. Ultrasonography was normal. In urodynamic investigation we found in voiding cystometry: high bladder compliance, low bladder sensation with F.D. at capacity of 1000 ml. With normal relaxation in the EMG, detrusor contractions were observed neither in lying nor in sitting position. There was no pathology in the cystoscopy. Consulting neurologist found no pathology. EEG was normal. Conservative treatment with intermittent catheterisation, alfa-blocker and cisapride was continued. Consulting psychiatrist prescribed Mianserin. No spontaneous miction was observed after three weeks of this conservative treatment. The girl was sent to sanatorium, where she continued therapy. After 10 day resting in sanatorium she started spontaneous micturitions. She refused further cystometric examinations. In five consecutive uroflowmetries she passed 280 to 780 ml of urine in one portion with high flow rates. CONCLUSIONS: 1. Both functional and psychogenic factors are important in the development of "Lazy Bladder Syndrome". 2. In patients with voiding dysfunction the results of urodynamic evaluation are the most important. 3. Multispecialistic team is needed in the treatment of children with "Lazy Bladder Syndrome".

Adolescent↗
PubMed1997

Low-dose radiation therapy for age-related macular degeneration.

BACKGROUND: The study was carried out to evaluate the effect of low-dose radiation therapy in patients with age-related macular degeneration. METHODS: One hundred eyes of 78 patients (mean age 72 years) with different forms of age-related macular degeneration were treated with external beam radiotherapy between 1971 and 1989. In four fractions a total dose of 2 Gy was administered over 7 days. Radiation therapy was performed by the conventional 200-kV technique. The mean duration of follow-up period was 7 years (range 0.5 to 20 years). A control group was composed of 96 eyes from patients with AMD who received no therapy. The mean visual acuity at first presentation and the duration of follow-up was the same as in the treatment group. RESULTS: No difference in visual acuity between the treatment and control groups could be observed. After 1, 2, 5 and 10 years the mean visual acuity was equal in the radiation group and the control group. Even in subgroup analysis regarding only the eyes with exudative forms of AMD, no effect of this treatment strategy could be demonstrated. CONCLUSION: Our results suggest that low-dose radiation therapy in patients with age-related macular degeneration has no beneficial effect. However, it must be considered that the dose of 2 Gy is low in comparison to doses used in recently published studies (5-24 Gy).

Aged↗
PubMed1997

[Retinal detachment in Ehlers-Danlos syndrome. Treatment by pars plana vitrectomy].

UNLABELLED: Ehlers-Danlos syndrome (EDS) is an hereditary connective tissue disorder caused by defective collagen synthesis, the main features being hyperelasticity and vulnerability of the skin, recurrent bleeding from fragile blood vessels, and secondary deformities of the joints. Ocular involvement is a rare occurrence, e.g., corneal and scleral rupture from minor blunt injury, lens displacement, rhegmatogenous retinal detachment. To date, few reports exist concerning the treatment of retinal detachment in Ehlers-Danlos syndrome, all of them dealing exclusively with conventional scleral buckling surgery. PATIENT AND METHODS: We report on a 47-year-old male patient suffering from EDS type VI (so-called ocular type, lysine-hydroxylase deficiency). He presented with rhegmatogenous retinal detachment in his only eye. A scleral buckling procedure was not feasible because of marked scleral atrophy. A three-port vitrectomy was therefore carried out. RESULTS: During the operation, pronounced choroidal detachment and bleeding developed, subsiding within weeks postoperatively. Closure of the sclerotomies was difficult due to scleral thinning. Two revitrectomies were necessary because anterior PVR with traction retinal detachment occurred. The last revitrectomy was performed 18 months ago, and the retina has been completely reattached under 5000 cs silicone oil since then. Visual acuity is 0.1. CONCLUSION: Primary vitrectomy permits successful treatment of retinal detachment in EDS patients if a buckling procedure cannot be performed because of scleral atrophy. However, serious complications may occur. Surgical procedures other than primary vitrectomy should therefore always be carefully considered, e.g., pneumatic retinopexy, temporary balloon, dura patch with episcleral pocket.

Ehlers-Danlos Syndrome↗
PubMed1997

[Labor monitoring and indications for abortion and cesarean section in eye diseases--an overview].

BACKGROUND: Management of labor and indications for abortion in ophthalmologic diseases are discussed controversially in literature. Overtreatment is still frequent. In diseases like pseudotumor cerebri, high myopia, retinal detachment, retinopathy in EPH-gestosis, uveal melanoma and diabetic retinopathy, the question for optimal management of labor or interruption rises mainly from gynaecologists. METHODS: In this review these conditions will be discussed with the literature--obtained by a medline-research. CONCLUSIONS: In the ophthalmologist's point of view--there are no indications for interruption or section caesarean in patients with above mentioned ophthalmologic diseases.

Abortion, Eugenic↗
PubMed1997

[Pseudotumor cerebri and pregnancy--a case report].

BACKGROUND: Indications for section caesarean or interruption in ophthalmologic diseases are discussed controversially in the literature and are often overemphasized. CASE REPORT: A 34-year-old VII-gravida VI-para consulted our clinic for the first time in her 14th week of pregnancy because of bilateral papilledema. There was no indication for EPH-gestosis, neurological examination als well as MRT were normal. In control examinations--first every 3 weeks, then with the beginning of the 30th week of pregnancy every week--the clinical course was uneventful: visual acuity remained on both sides 1.0, on the right eye more than on the left eye the discs appeared prominent with hazy margins, the blind spot was enlarged on the right eye more than on the left eye. Furthermore there was intermittent myopia. In the 37th week of pregnancy section caesarean was performed because of gynecological indications. At the last examination, 4 weeks later, there was a nearly complete restitution ad integrum. CONCLUSION: Indications for section caesarean or interruption in patients with papilledema due to pseudotumor cerebri will be discussed with the literature.

Adult↗
PubMed1996

Vitrectomy in diabetic patients with a blind fellow eye.

Results of pars plana vitrectomy for complications of proliferative diabetic retinopathy were analysed in 32 consecutive patients with a blind fellow eye due to diabetic eye disease. The mean follow-up period was 22.3 months. Only 16% of all eyes examined had received full scatter photocoagulation prior to referral for vitrectomy. Out of 9 eyes with vitreous haemorrhage, 8 improved to a visual acuity of > or = 0.2 postoperatively. Amid 23 eyes which were vitrectomized for advanced traction retinal detachment, only 4 eyes improved to a postoperative visual acuity of > or = 0.02. In this group 12 eyes deteriorated after vitrectomy, 3 eyes progressing to no light perception. The postoperative visual outcome after vitrectomy for traction retinal detachment in this group of diabetics with a blind fellow eye (mean postoperative visual acuity 0.03 +/- 0.05) was significantly worse (p < 0.000) compared to a group of 196 patients with a seeing fellow eye who were vitrectomized for traction retinal detachment at our clinic (mean postoperative visual acuity 0.09 +/- 0.11). Therefore we conclude that traction retinal detachment in this subgroup of patients is a particularly severe presentation of diabetic retinopathy with a guarded functional prognosis after vitrectomy. Our results demonstrate the importance of timely full scatter photocoagulation and early vitrectomy in eyes with progressive fibrovascular proliferation not responding to panretinal photocoagulation. We conclude that especially diabetic patients with a blind fellow eye must be followed closely and assigned to vitrectomy at an earlier stage of their disease in order to improve functional prognosis.

Adult↗
PubMed1996

[Complications of preventive cryoretinopexy in retinal foramina and degeneration in 1,000 eyes].

INTRODUCTION: Prophylactic treatment of full-thickness retinal breaks is widely accepted. The side effects and benefits of prophylactic treatment, however, have to be considered critically. The complication rates of prophylactic procedures must be compared. The aim of our study was to find out the complication rate of cryopexy in prophylactic retinal surgery. PATIENTS: Retrospectively we analyzed 1000 eyes of 746 patients who were prophylactically treated by cryopexy for different reasons. We included eyes with round holes, horse shoe tears and peripheral degenerations. Follow-up time ranged from 6 months to 7 years (average 30 months). RESULTS: Further surgical treatment was necessary in 3.4% of the patients (1.8% had a second cryopexy, 0.1% needed laser coagulation, and in 1.5% a subsequent scleral buckling procedure was necessary. In 17.6% of these cases (0.6% of all cases) the retinal detachment occurred in the periphery of the primary cryopexy after more than 1 year. In all our patients we did not find postoperative macular pucker or cystoid macular edema. CONCLUSIONS: The complication rate of cryopexy performed for the treatment of retinal holes and degeneration is low. This method has to be regarded as a therapeutic tool in the prophylactic treatment of (dangerous) retinal areas.

Adolescent↗
PubMed1996

Management of retinal redetachment following silicone-oil removal.

The aim of the present investigation was to study the clinical course of eyes presenting with retinal redetachment after silicone-oil removal (SOR), with special regard being paid to the long-term visual outcome. Between October 1989 and September 1994, SOR was performed on a consecutive series of 262 eyes that had previously undergone vitrectomy combined with silicone-oil injection for complex retinal detachments. The records of these patients were analyzed retrospectively. The mean follow-up period after redetachment following SOR was 26.3 (range 6-45) months. Redetachment occurred in 35 eyes (13.4%), mostly within 1-3 months of SOR. Redetachment was not dependent on the surgical procedure or the underlying disease. A total of 24 eyes were revitrectomized and a stable flat retina was the result in 23 eyes (65.7%). At the latest follow-up visit, 18 eyes (51.4%) had a visual acuity (VA) of > or = 0.02 and 14 eyes (40%) had a VA of > or = 0.1. In 12 eyes (34.3%) the final VA equalled the best VA recorded before redetachment; an increase in VA occurred in 6 eyes (17.1%) and a deterioration was noted in 17 eyes (48.6%). Only 6 of the 17 eyes that deteriorated had displayed a VA of > or = 0.02 prior to SOR and lost formed vision due to redetachment; these 6 eyes represent 17.1% of the eyes presenting with redetachment after SOR and 2.3% of all 262 eyes that had undergone SOR. These observations demonstrate that revitrectomy is an effective treatment for retinal redetachment after silicone-oil removal. The final failure rate does not appear high enough to justify a contraindication for routine removal of silicone oil, especially since it remains a matter of speculation as to whether these eyes would have fared better had removal of silicone oil been avoided.

Adolescent↗
PubMed1996

[Intrastromal keratectomy in high myopia. 1 year results].

Photorefractive keratectomy (PRK) by excimer laser is now a scientifically established treatment method in low and moderate myopia. In high and very high myopia, however, the formation of severe corneal haze or scars and a considerable regression of refraction remain obstacles to the use of PRK. One approach to these two problems is to perform an intrastromal keratectomy. PATIENTS AND METHOD. Between September 1992 and September 1994 intrastromal keratectomy was carried out in 42 eyes with myopia between -8.625 and -36 D. Twenty-one eyes (spherical equivalent of pre-operative refraction between -12.12 and -36 D) were treated by keratomileusis in situ, and 21 eyes (spherical equivalent of pre-operative refraction between -8.625 and -29.25 D) by intrastromal excimer laser keratectomy. Thirty-two eyes were followed up for at least 12 months. RESULTS. The post-operative refraction (spherical equivalent) ranged between +1.375 D and -5.0 D in the keratomileusis in situ group and between +1.5 D and -3.0 D in the intrastromal excimer laser keratectomy group. Nearly all patients regained their pre-operative visual acuity quickly. In the long-term follow-up (1 year) no significant regression of refraction occurred; the pre-operative visual acuity was regained in both groups after 1 year. Significant astigmatism was not induced. CONCLUSIONS. Intrastromal keratectomy is able to correct even very high myopias quite precisely and without regression of the refractive outcome. In addition, considerable haze can be avoided. For these reasons, in high and very high myopia intrastromal keratectomy seems to be superior to conventional anterior photorefractive keratectomy (PRK) by excimer laser.

Adult↗
PubMed1996

Prediction of visual acuity after early vitrectomy in diabetics.

In proliferative diabetic retinopathy the indication of early vitrectomy remains controversial. At present, no decision rule exists for the assessment of the various factors predicting the postoperative visual outcome. We reviewed 75 vitrectomies in 68 diabetics from our clinic. All vitrectomies were done by one surgeon. In all cases, vitrectomy was indicated because of nonclearing vitreous hemorrhage and/or fibrovascular proliferation. A linear regression model was used to identify factors correlating with the visual outcome. By means of univariate analysis, six of nine clinical variables were found to be associated with the final visual outcome. Dividing the patients into two groups according to their preoperative visual acuity (group 1 hand movement, group 2 better than hand movement), we identified two predictors that were independently associated with the postoperative visual acuity: group 1-the visual acuity of the fellow eye (P < 0.05) and rubeosis iridis (P < 0.05); group 2-the visual acuity of the fellow eye (P < 0.001) and preexisting systemic diabetic vascular disorders (P < 0.01). Based on this model, a formula was derived to predict the visual acuity at 6 months postsurgery. For easier handling the prognostic factors of a poor visual outcome (less than 0.1) were summarized in a flow chart. The test is a useful tool for the preoperative evaluation of various risk factors and, hence, for more reliable prediction of a poor visual outcome. Thus, it may be especially useful to objectify the risk-benefit ratio for early vitrectomy in diabetics.

Diabetic Retinopathy↗
PubMed1996

Linkage between research sponsorship and patented eye-care technology.

PURPOSE: To examine the linkage between the funding of ophthalmologic and related biomedical research and the development of patented eye-care technology using data on patents granted and the scientific literature cited by those patents. METHODS: The United States patents granted during the 20-year period from 1975 through 1994 were screened using patent office classifications and key words to identify all eye-care-related patents. Each patent's nonpatent references (references to literature other than previously granted patents) were examined, and those references to scientific papers then were reviewed to determine the authors' institutions and acknowledged funding sources. RESULTS: Major findings include the following: (1) Eye technology innovation has grown steadily, with a threefold increase in number of patents granted from 224 in 1975 to 662 in 1994. (2) The cited scientific base that supports this technology has grown even more rapidly, with a sixfold increase in the average number of nonpatent references, from fewer than 0.5 per patent in 1975 to more than 3.0 in 1994; as a result, the total number of nonpatent references has increased by a factor of 20, from 100 in 1975 to 2000 in 1994. (3) The National Eye Institute is the leading single institution in providing support for this research: 31% of all eye-care patents with science references cite papers that contain at least one acknowledgment to National Eye Institute (NEI) support; and when NEI is combined with the rest of the National Institutes of Health (NIH), 41% of the patents with science references are linked to NIH-funded research. (4) Patent science dependence, as measured by science references, is greatest for technologies related to medical treatment, surgical instruments, and intraocular lenses; moderate for diagnostic instruments and contact lens; and least for eyeglasses. CONCLUSIONS: The NIH and other sponsored vision research is of direct and increasing relevance to the growing number of US patented eye-care technologies.

Animals↗
PubMed1996

[Early diagnosis and therapy of diabetic retinopathy].

Diabetic eye disease, especially diabetic retinopathy including maculopathy, is the most common cause of blindness in industrialized countries. However, if adequate treatment (photocoagulation, vitrectomy) is started timely, severe visual loss from this disease can be prevented in most instances. This paper reports on clinical findings, classification and treatment of diabetic eye disease. It is emphasized that only an effective screening and prevention strategy can lead to a reduction of blindness from diabetic retinopathy.

Adult↗
PubMed1996

In vivo observation of corneal nerve regeneration after photorefractive keratectomy with a confocal videomicroscope.

The aim of the present study was to study corneal nerve regeneration after photorefractive keratectomy (PRK) in vivo by means of a confocal videomicroscope. A total of 25 myopic eyes of 16 patients were examined biomicroscopically and with the confocal microscope (Microphthal, Hund Company, Wetzlar, Germany) before and after PRK. The mean age of the patients was 30.4 (range 21-44) years, the mean follow-up period was 13.7 (11.0-15.1) months, the mean preoperative refraction was -5.5 (-1.75 to -9.0) D, the mean amount of attempted correction was -4.75 (-1.75 to -7.5) D, the mean ablation depth was 50 (30-75) microns, and the single central ablation zone measured 6.0 mm in diameter. The postoperative refractive and visual outcome was favorable in most eyes. The mean postoperative refraction was -0.5 (-2.75 to + 0.5) D. Among the 25 eyes, 22 (88%) had +/- 1.0 D of attempted correction at 1 year and only 2 eyes showed a loss of 2 Snellen lines. Despite increased light scattering and reflection due to haze, sufficient postoperative imaging of the corneal nerve architecture was possible in all cases. Recovery of corneal innervation started from the margin of the ablation, being directed toward the center of the cornea and the epithelium. At 5-8 months following PRK, stromal nerves and the subepithelial nerve plexus took on their definite appearance. The original nerve structure was not reestablished, abnormal branching and accessory thin nerve fibers being present without exception. Confocal slit-scanning video-microscopy is a very useful technique for in vivo investigation of corneal nerve regeneration after PRK and, presumably, other keratorefractive procedures. In comparison with histology studies in animals, reinnervation of the human cornea after PRK seems to be completed earlier but follows the same morphologic principles.

Adult↗
PubMed1996

Corneal reinnervation after photorefractive keratectomy and laser in situ keratomileusis: an in vivo study with a confocal videomicroscope.

The purpose of this study was to compare the regeneration of corneal nerves after photorefractive keratectomy (PRK) versus laser in situ keratomileusis (LASIK) in vivo with a confocal videomicroscope. In all, 15 eyes that had undergone PRK and 15 eyes that had been subjected to LASIK were compared with a confocal in vivo slit-scanning video-microscope. The subepithelial nerves were observed preoperatively and at 3, 6, and 12 months postoperatively. In all eyes, good microscope images of the subepithelial nerve plexus could be obtained preoperatively. Because of postoperative light reflection and scattering in the treated area, subepithelial nerve-fiber regeneration could be followed satisfactorily only in seven eyes after PRK and in five eyes following LASIK. In the eyes treated with PRK, recovery of subepithelial reinnervation started from the margin of the ablation zone, being directed toward the center of the cornea. At 8 weeks postoperatively, rarefied subepithelial nerve fibers were visible at the edges, and after 3 months, single nonbranched nerve fibers could be visualized in the center of the ablation zone. At 6-8 months following PRK, subepithelial nerve regeneration seemed to be completed; however, abnormal branching and accessory thin nerve fibers were present without exception. After LASIK, corneal nerve-fiber regeneration followed the same course described for PRK except that regenerated subepithelial nerve fibers were barely visible in the center after 6 months. Further changes in nerve structure were visible for up to 12 months postoperatively. Recovery of corneal sensitivity in humans has been reported to start at 4-6 weeks after PRK and is said to be completed within 6-12 months of surgery. Slit-scanning videomicroscope findings were in accordance with these observations.

Cornea↗
PubMed1995

Optical sectioning of the cornea with a new confocal in vivo slit-scanning videomicroscope.

PURPOSE: The purpose of this article is to introduce a newly developed confocal in vivo slit-scanning microscope for continuous recording and real-time imaging of the various corneal subsegments of the patient's eye with high microscopical resolution and adequate contrast. METHODS: One-dimensional confocal slit-scanning videomicroscopy of the human cornea was performed with an instrument mainly consisting of a scanning module, an image-intensifier video camera, a video monitor, and a synchronization unit for matching optical scan and video cycle with respect to frequency and phase. Light intensity or fluorescence intensity profiles through the cornea could be obtained by microphotometric recording of part of the imaging light. An immersion contact technique using an isotonic tear replacement liquid with thixotropic properties avoids any mechanical contact between the front lens of the microscope objective and the corneal surface. RESULTS: In normal human eyes, the corneal micromorphology could be made visible with satisfactory lateral and axial resolution and with good contrast. The separately focussed sections of the cornea showed the endothelial cells, the superficial, intermediary, and basal cells of the epithelium, as well as stromal keratocytes and nerves. Even in eyes with significant corneal opacities resulting from corneal edema, the endothelial pathology could be imaged with sufficient contrast. CONCLUSION: The in vivo slit-scanning videomicroscopy offers real-time noninvasive and noncontact serial imaging of corneal subsegments with resolution and imaging contrast. Thus, an important step toward using confocal scanning microscopy for corneal diagnosis seems to be done.

Cornea↗
PubMed1995

[Evaluating vision after photorefractive keratectomy within the scope of legal police service requirement 300].

BACKGROUND: The Polizeidienstvorschrift (PDV) 300 is a regulation which prescribes visual requirements for applicants to the German Police Service. Among other demands, uncorrected visual acuity (VA) of both eyes must be at least 0.5 before age 18 and at least 0.3 after age 21. The spherical equivalent of spectacle correction is ordained to fall into the range between -2.0 and +3.0 dpt. To date, recommendations for the assessment of excimer laser photorefractive keratectomy (PRK) with a view to Police Service applicants are still lacking. PATIENTS: Two applicants with myopic astigmatism were treated by PRK in order to meet the refractive requirements for entering the German Police Service. The first patient was judged fit for service two weeks after PRK was performed on his right eye. At this time uncorrected VA was 1.0 VA under glare conditions and contrast sensitivity had not been tested. The second patient had a stable postoperative refraction with an uncorrected VA of 1.0 in both eyes at six months postoperatively. VA under glare conditions and contrast sensitivity were normal. However, the medical service of the police authority demanded an additional follow-up of six months before judging this applicant fit for service. CONCLUSIONS: Before excimer laser PRK is performed in myopic police service applicants, a careful examination should rule out disorders of the visual system which are not related to the refractive error and may preclude admission into the police service. After PRK in this group of persons, a postoperative standard follow-up of at least six months should be demanded. Since fitness for night driving, self-defence ability and good orientation under difficult visual conditions are mandatory for police officers, any ophthalmologic certificate should make definite statements about glare and contrast sensitivity.

Adolescent↗