PubMed Health⌕ Search

Biomedical subjects

K U Bartz-Schmidt

Publications and source records attributed to K U Bartz-Schmidt.

At least 37 records · Page 2Linked to original sources
PubMed2005

[Recommendation for the implementation of intravitreal injections--statement of the German Retina Society, the German Society of Ophthalmology (DOG) and the German Professional Association of Ophthalmologists (BVA)].

The intravitreal injection as a minimally invasive intervention has proved to be an effective therapy in the management of numerous vitreoretinal diseases. However, non-standardized performance of the procedure might cause severe complications. The recommendations for intravitreal injections discussed here are intended to contribute to a minimization of the risk for complications. Of particular importance are a meticulous preoperative antisepsis with povidone iodine, a sterile environment using a sterile lid speculum, drape and gloves, the use of an adequate injection technique and the exclusion of postoperative retinal non-perfusion.

Eye Diseases↗
PubMed2004

[Ocular side effects and complications of intravitreal triamcinolone acetonide injection].

With the advent of intravitreal triamcinolone acetonid injections major focus was assigned to potential ocular side effects. The current discussion is dominated by the potential cytotoxicity of particular biologically incompatible components. Those are regarded as substantial pathogenetic factor of the sterile pseudoendophthalmitis that seems to be avoidable by meticulous purification of the commercially available preparations. Even sustained subretinal or epiretinal deposits disclosed no signs of retinal toxicity. Major ocular side effects comprise temporary corticosteroid glaucoma and progressive cataract formation. Infectious endophthalmitis represents a rare but serious complication that might be set into critical context with hygienic surgical standards applied. Due to steroid-induced immune suppression clinical signs of inflammation might be masked and a proper diagnosis delayed. Other rare complications reported include a transient central retinal artery occlusion, conjunctival ulcerations, retinal detachment and potential reactivation of a cytomegalovirus retinitis. In conclusion, ocular side effects and complications show a wide variety of clinical signs and underlying causal mechanisms. However, the consequences are mostly temporary and show a good response to therapeutic intervention.

Anti-Inflammatory Agents↗
PubMed2004

[Vitrectomy with or without cerclage in the treatment of retinal detachment].

In the beginning, pars plana vitrectomy was often combined with encircling elements in the treatment of complicated retinal detachments. Initial considerations were the limited control of the vitreous base due to the restricted view of the fundus periphery and the prevention of redetachment by anterior tears or traction. Today, additional encircling is justified in specified conditions of retinal surgery, e.g., retinal shortening by long-lasting detachments, anterior PVR, or choroidal injuries. Despite several synergistic effects in surgical management, severe complications have to be taken into account for scleral buckling in vitreoretinal surgery. Nevertheless, primary vitrectomy in combination with scleral buckling has led to a marked decrease of primary failure rate and improvement of functional results in retinal detachment surgery.

Combined Modality Therapy↗
PubMed2004

[Eye trauma in childhood and youth].

Childhood trauma of the eye and its adnexa represents approx. 4 - 20 % of all eye injuries. Due to ambiguous patient history and limited cooperation a comprehensive diagnosis of pediatric eye trauma is often difficult. The weakness of the infantile cornea, the thin and elastic anterior lens capsule, and the firm vitreous with its strong adherence to the retina bear particular intra- or postoperative problems. Moreover, the quick development of secondary cataract and the high risk of PVR may complicate the posttraumatic and postoperative course. Small infants represent a special subgroup in various regards mainly because of the risk of amblyopia which often causes functional loss in spite of a good anatomical reconstruction. The relative frequency of certain injuries differs between children and adults. The ocular manifestation of child abuse as well as bite and fireworks injuries are characteristic for childhood and will be discussed more in detail.

Adolescent↗
PubMed2004

Clinicopathological findings of choroidal neovascularisation following verteporfin photodynamic therapy.

AIMS: To report the clinicopathologic findings of surgically excised choroidal neovascularisation (CNV) three days after verteporfin photodynamic therapy (PDT). METHODS: In three patients (three eyes) with age related macular degeneration, the CNV was surgically removed three days after PDT. The CNV specimens were examined by light microscopy. RESULTS: The patients had subfoveal classic CNV. Fluorescein angiography revealed non-perfusion of the CNV after PDT and before surgery in all eyes. The light microscopy of the CNV membranes showed swollen and damaged endothelium. Thrombus formation or vascular occlusion in the CNV vessels was not detected. CONCLUSION: PDT did not cause a thrombosis of the vessels within the CNV three days after PDT. Severe endothelial damage of the CNV was observed and is likely a primary effect of PDT. Non-perfusion of the CNV at this stage is possibly secondary to occlusion at a deeper level, namely the underlying feeding choroid.

Aged↗
PubMed2004

Reproducibility of circadian retinal and optic nerve head blood flow measurements by Heidelberg retina flowmetry.

BACKGROUND/AIM: The Heidelberg retina flowmeter (HRF) is designed to measure retinal capillary blood flow. Previous studies however showed weak reproducibility of data. The intraindividual reproducibility of circadian HRF measurements was examined in healthy subjects in three locations of the retina. METHODS: 36 healthy volunteers (27.3 (SD 4.3) years) were examined by HRF seven times a day (t0-t6). Using a default window of 10 x 10 pixels, three consecutive measurements were performed in three precise focusing planes: superficial, intermediate and deep layer, peripapillary retina, neuroretinal rim and cup, respectively. Images of identical tissue locations identified by capillary landmarks of each layer were selected to quantify the retinal microcirculation of each volunteer. Means and standard deviations of all flow results of a given subject were calculated, at t0-t6 and the coefficients of variation as a measure of reproducibility. RESULTS: The coefficients of variation ranged between 8.4% and 41.0% in the superficial layer (mean 19.8% (SD 8.4%)), 10.6%, and 43.0% in the intermediate layer (mean 24.0% (SD 8.4%)), and 9.9% and 84.0% (mean 29.6% (SD 15.8%)) in the deep layer. CONCLUSIONS: These data show the best reproducibility of measurements in the superficial layer followed by the intermediate and the deep layer. Clinically, this is an unsatisfactory intraindividual reproducibility of flow values in each studied layer.

Adult↗
PubMed2004

Histopathological analysis in experimental macular surgery with trypan blue.

AIM: To analyse the effect of trypan blue on the retina in an experimental setting of macular surgery. METHODS: Porcine eyes were used within 3 hours after death. The eyes were hemisected and the vitreous removed. Trypan blue (0.15%) was applied over the trephined posterior pole, whereas the rest of the eye cup was filled with a balanced salt solution (BSS). The dye and the BSS were removed after 1 minute and the complete eye cup irrigated and filled with fresh BSS. Both the treated and untreated retinas were illuminated with a standard surgical light pipe and source at maximum power for 10 minutes. Both the trypan blue exposed retina and the non-treated surrounding retina were processed for histology. RESULTS: Exposure of the retina to trypan blue for 1 minute, followed by illumination caused no histologically detectable damage compared to the controls. No microarchitectural disorganisation, cellular disruption, or affection of the vitreoretinal interface was detected. CONCLUSIONS: These findings indicate that a 1 minute exposure of trypan blue followed by illumination does not cause an acute morphologically detectable toxic effect on the porcine retina.

Animals↗
PubMed2003

Clinicopathological correlation of choroidal neovascularization after external beam radiotherapy in age-related macular degeneration.

PURPOSE: To analyze the histopathology of choroidal neovascularization after external beam radiotherapy in age-related macular degeneration. METHODS: A retrospective non-case-matched comparative histopathologic study. The histoarchitecture of nine surgically removed subretinal specimens from nine patients that had undergone external beam radiotherapy for exudative age-related macular degeneration was studied. Seven patients had received 20 Gy in 10 fractions and two 15 Gy in 5 fractions with an average time interval between radiotherapy and surgical extraction of 14 months (range 3-28). A consecutive series of classic, mixed and occult choroidal neovascular membranes served as controls. RESULTS: Clinical findings. Radiation-associated choroidal neovasculopathy was angiographically suspected in four patients: a coarse net of vessels on fluorescein angiography developing at the border of previously irradiated choroidal neovascularization was observed in three patients; blebs at the margin of a plaque on indocyanine green angiography were observed in two patients. Pathological findings. Diffuse drusen as well as intra-Bruch's fibrovascular tissue was found in all irradiated specimens. In four specimens an edematous vascularized layer was seen between diffuse drusen and normal-appearing intra-Bruch's fibrovascular tissue. This lesion was not found in the control specimens. A particular correlation for the bleb lesion was not recognized. CONCLUSION: The appearance of an edematous subretinal pigment epithelial vascularized layer between diffuse drusen and normal-appearing fibrovascular tissue in four of nine irradiated membranes may be secondary to previous irradiation. It may correlate with the unusual exudative manifestations observed after external beam radiotherapy.

Aged↗
PubMed2003

Retinectomy for treatment of intractable glaucoma: long term results.

AIM: To report long term efficacy and complications of retinectomy as an intraocular pressure lowering procedure for intractable glaucoma. METHODS: This was a consecutive interventional case series. In 44 consecutive eyes (39 patients, 22 men and 17 women) retinectomy was performed to lower the intraocular pressure (IOP) in patients with uncontrolled IOP (>35 mm Hg for more than 4 months) despite conventional filtering surgery and drug treatment. Pars plana vitrectomy was performed and the peripheral retina was surgically excised to various degrees. The procedure was concluded by an intraocular gas tamponade of 20% C(3)F(8). Included were patients with neovascular glaucoma (12 eyes), infantile and juvenile glaucoma (three eyes), secondary glaucoma due to aphakia (13 eyes), severe ocular trauma (seven eyes), uveitis (seven eyes), and glaucoma in Ehlers-Danlos syndrome (two). RESULTS: All patients underwent successful surgical retinectomy. All patients were followed for 5 years. Mean postoperative IOP after 4 years was 15.7 (SD 9.4) mm Hg, representing a decrease of IOP by 61% compared to the preoperative level (41.2 (9.4) mm Hg). In 52.3% of eyes long term regulation of IOP could be achieved without complications. Retinectomy was least effective in neovascular glaucoma because of central retinal vein occlusion (CRVO). Eyes with glaucoma secondary to uveitis showed a tendency towards low IOP levels with subsequent phthisis bulbi. The initial visual acuity of all patients was lower than 20/50 (mean 1.8 (0.8) logMAR) in the treated eye. Final visual acuity was 2.3 (0.6) logMAR. 21 out of 44 cases developed retinal complications (retinal detachment or proliferative vitreoretinopathy (PVR)) after surgery, requiring silicone tamponade in 11 eyes (52%) either for persistent low IOP or for PVR. Nine eyes developed phthisis, seven of which were enucleated during the follow up. CONCLUSIONS: Long term results after retinectomy demonstrate its efficacy in otherwise intractable glaucoma. Efficacy and safety of retinectomy are dependent on the underlying disease.

Adult↗
PubMed2002

Clinicopathologic correlation in hemorrhagic age-related macular degeneration.

PURPOSE: To analyze and compare the histopathology of surgically extracted membranes in hemorrhagic age-related macular degeneration (AMD) versus extracted classic, mixed and occult choroidal neovascularization (CNV) in AMD. METHODS: Thirty consecutive membranes, surgically removed in hemorrhagic AMD, were analyzed and compared with consecutive series of 50 classic, 20 mixed and 20 occult membrane specimens in exudative AMD. The specimens were serially sectioned and stained in a stepped fashion with hematoxylin-eosin, Masson trichrome and periodic acid-Schiff stain. RESULTS: Diffuse drusen were observed in all hemorrhagic AMD specimens, fibrovascular tissue was found in 29 of 30 specimens which was located subretinally in 11 specimens and/or in Bruch's membrane in 28 specimens. A hemorrhage was located subretinally in 21 specimens, in the stroma of the fibrovascular tissue in 17 specimens, at the choroidal side of the diffuse drusen adjacent to fibrovascular tissue in 13 specimens and at the choroidal side of the fibrovascular tissue in Bruch's membrane in 8 specimens. Grossly dilated thin-walled vessels were identified in one hemorrhagic AMD case, suggestive of polypoidal choroidal vasculopathy. Scarred tears of the retinal pigment epithelium were identified in two specimens. CONCLUSION: A large spectrum of histo-architectural lesions is recognized in hemorrhagic maculopathy. Hemorrhages do not only characteristically appear in the subretinal space or in the stroma of the neovascular tissue but also at the choroidal side of the diffuse drusen adjacent to the neovascular complex and at the choroidal side of the intra-Bruch's fibrovascular tissue.

Humans↗
PubMed2002

[Macular translocation with 360 degree retinotomy in the treatment if exudative macular degeneration. Functional and angiographic results].

BACKGROUND: During surgical extraction of choroidal neovascular membranes (CNV) in age-related macular degeneration (AMD), the defective foveal retinal pigment epithelium (RPE) is removed. Subsequent translocation of the foveal neural retina to adjacent healthy RPE should result in stabilization and possibly improvement of visual acuity. METHODS: A prospective case series was carried out using controlled surgery and examination protocols with examinations made at fixed intervals. The surgical procedures combine counterrotation of the globe, phacoemulsification and implantation of a posterior chamber lens, complete vitrectomy, induction of a total retinal detachment, 360 degrees anterior retinotomy, removal of the subfoveal neovascular complex, foveal translocation outside the RPE defect, reattachment of the retina using F6H8, peripheral laser retinopexy and temporary silicone oil tamponade. PATIENTS: Macular translocation surgery was performed on 100 patients between December 1997 and December 1999. All patients had experienced recent visual loss due to exudative AMD and of these, 26 patients had major macular subretinal hemorrhage, 39 patients had occult and 25 patients classic subfoveal choroidal neovascularization. The preoperative findings in the remaining patients included tears in the pigment epithelium (n = 4), polypoidal choroidal vasculopathy (n = 1), recurrent subfoveal CNV following laser therapy (n = 2) and deep retinal vascular anomalous complexes (n = 3). RESULTS: A total of 97 patients completed the 12-month examination. Visual acuity increased by 15 or more ETDRS chart letters in 24 patients, remained stable in 42 patients and deteriorated by 15 or more EDTRS chart letters in 34 patients 12 months postoperatively. The silicone oil tamponade was removed in 97 patients, in 10 patients, silicone oil had to be reinjected because of severe complications. A secondary procedure was necessary in 25 patients, primary PVR was observed in 9 eyes, secondary PVR developed in 10 eyes, a macular pucker in 5 eyes and a macular hole in 1 patient. Other postoperative complications included persistent hypotonia, macular edema, IOL dislocation, keratopathy and recurrent CNV (n = 3). CONCLUSIONS: Macular translocation is a technically demanding operation, which requires a considerable learning curve. Although the procedure has a high rate of surgical and postoperative complications, the functional and anatomical results appear to be promising for selected patients with subfoveal CNV secondary to AMD.

Aged↗
PubMed2002

[Visual prognosis and patient selection].

Choroidal neovascularization (CNV) is one of the leading causes of central vision loss. Laser photocoagulation and photodynamic therapy may reduce the risk of severe loss of visual acuity in subfoveal CNV secondary to age-related macular degeneration. However, the most favorable effect of these therapies is the slowing of the vision loss. Macular translocation surgery, removing the neurosensory retina away from the area of choroidal neovascularization to a healthier underlying tissue, may improve or stabilize the visual acuity. Several pilot studies of this surgery reported visual recovery in selected patients. Well-designed, controlled randomized studies are needed to clarify the role of the macular translocation surgery in treatment of choroidal neovascularization. Given the severe complications of this surgery, it is of utmost importance to discuss the potential risks and advantages of this procedure with the patient.

Choroidal Neovascularization↗
PubMed2002

Biocompatibility tests on the intraocular vision aid IOVA.

Intraocular miniaturized image transmission systems are developed to restore vision in patients with irreversible destruction of the anterior ocular segment (i.e. chemical burns, explosion trauma, trachoma) and high risk for corneal transplantation, provided that the posterior ocular segment is intact. To ensure safety of such a device biocompatibility tests were conducted. In the present study the effects of light and temperature in various intensities and the toxicity of the implanted materials on neural function in the rabbit retina in-vivo was investigated. All tests give encouraging results concerning the feasibility of intraocular miniaturized image transmission systems.

Animals↗
PubMed2001

Partial deletions of the long and short arm of chromosome 3 point to two tumor suppressor genes in uveal melanoma.

Uveal melanoma is the most common form of primary eye cancer. Monosomy 3, which is an unusual finding in tumors but is present in approximately 50% of uveal melanomas, is significantly correlated with metastatic disease. To obtain positional information on putative tumor suppressor genes on this chromosome, we have investigated tumors from 333 patients by comparative genomic hybridization, microsatellite analysis, or conventional karyotype analysis. A partial deletion of the long arm was found in eight tumors, and the smallest region of deletion overlap (SRO) spans 3q24-q26. We found six tumors with a partial deletion of the short arm and were able to define a second SRO of about 2.5 Mb in 3p25. This SRO does not overlap with the VHL gene. Our finding suggests a role for two tumor suppressor genes in metastasizing uveal melanoma and may explain the loss of an entire chromosome 3 in these tumors.

Chromosome Deletion↗
PubMed2001

Clinicopathological correlation in exudative age-related macular degeneration: recurrent choroidal neovascularization.

PURPOSE: To report the pathology of surgically removed submacular tissue in recurrent choroidal neovascularization after laser photocoagulation of classic choroidal neovascularization in age-related macular degeneration. METHODS: A recurrent subfoveal choroidal neovascular membrane was surgically removed in two patients. The recurrence was identified as a classic membrane on fluorescein angiography at the foveal border of the laser scar. A net was visualized in the early venous phase of the indocyanine green angiogram, with associated late hyperfluorescence. Both patients had undergone laser photocoagulation for a classic interpapillomacular choroidal neovascular membrane about 1 1/2 years earlier. The specimens were serially sectioned and stained with hematoxylin-eosin, periodic acid-Schiff, Masson trichrome and phosphotungstic acid-hematoxylin. RESULTS: The two specimens consisted of subretinal fibrovascular tissue with fibrin exudation. Fibrovascular tissue bordered subretinal fibrous tissue adherent to Bruch's membrane and remnants of the choroid in one patient. The fibrovascular portion most likely corresponded to the recurrence, whereas the fibrous portion represented the original membrane, being obliterated after photocoagulation. Some peripapillary tissue was additionally removed in the other patient. The latter lesion was invisible on fluorescein angiography but stained in the late phase of indocyanine green angiography and corresponded histopathologically to poorly vascularized intra-Bruch's fibrovascular tissue. Granular deposits, periodic acid-Schiff positive and metachromatically purple on Masson trichrome stain, representing diffuse drusen (basal laminar/linear deposits), were identified in the three specimens. CONCLUSION: A subretinal fibrovascular membrane corresponded with the classic recurrent choroidal neovascularization.

Aged↗
PubMed2001

Scleral buckling versus primary vitrectomy in rhegmatogenous retinal detachment (SPR Study): design issues and implications. SPR Study report no. 1.

BACKGROUND: In patients with more complex rhegmatogenous retinal detachments (RRD) not complicated by proliferative vitreoretinopathy (PVR), the most appropriate operating method is controversial, and different surgeons use different techniques. The Scleral Buckling Versus Primary Vitrectomy in Rhegmatogenous Retinal Detachments Study (SPR Study) is designed to compare primary vitrectomy and scleral buckling techniques in these patients. METHODS: The SPR Study is a multicentre, randomised, controlled clinical trial stratified by lens status. Patients with RRD which is not complicated by PVR grade B or C and which cannot be treated with a single meridional sponge are randomised to either scleral buckling or pars plana vitrectomy as first surgical intervention. Four hundred consecutive patients are to be recruited per subtrial (phakic and aphakic/pseudophakic patients), and followed up for 1 year. The primary endpoint (functional outcome) is the change in visual acuity. Secondary endpoints (anatomical outcome) include postoperative PVR, retinal reattachment and the number of reoperations necessary to achieve retinal reattachment. Twenty-seven institutions (49 surgeons) in six European countries have been recruited for participation in the study. CONCLUSION: The SPR Study is the first randomised prospective clinical trial to compare scleral buckling and primary vitrectomy in patients with RRD. The results of this study should enable vitreoretinal surgeons to improve the surgical therapy of patients with the more complicated manifestations of RRD.

Humans↗
PubMed2001

Variability of the normalised rim/disc area quotient estimated by laser scanning tomography. A comparison with conventional planimetry.

BACKGROUND: The introduction of the laser scanning tomograph raises the possibility of the estimation of optic disc morphology in a less subjective and less time-consuming way than the conventional planimetry of fundus photography. The aim of the present study was to estimate the efficiency of the HRT method in a comparison of data collected in a glaucomatous patient group to planimetric data obtained in young normal volunteers. METHODS: Repeated rim/disc area measurements were done in 10 glaucoma patients with a Heidelberg Retina Tomograph and in a group of five young volunteers with good vision. The intra-photographic, intra-observer examination of the planimetric method was compared to the inter-photographic assessment of the HRT technique. RESULTS: The variability of the mean normalised area ratio quotient was nearly 50% less using laser scanning tomography techniques (mean rim/disc area ratio = 0.17). CONCLUSION: The results show the superiority of HRT over the conventional planimetric technique. Furthermore, the much shorter processing time and the advantages of a computer-based databank in follow-up examination with HRT provides the hope that it could replace the rather time-consuming and subjective manual planimetric technique in the examination of glaucomatous optic nerve conditions.

Adult↗