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Anselm Kampik

Publications and source records attributed to Anselm Kampik.

97 records · Page 6Linked to original sources
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Pulsed electron avalanche knife in vitreoretinal surgery.

PURPOSE: To evaluate the advantages, disadvantages, safety, and surgical applicability of the pulsed electron avalanche knife (PEAK-fc), a new electrosurgical knife for "cold" and tractionless cutting, in vitreoretinal surgery. PEAK-fc is equipped with an integrated fiberoptic that makes bimanual procedures in intraocular surgery possible. METHODS: A prospective consecutive trial of 18 eyes in 18 patients who underwent vitreoretinal surgery for proliferative diabetic retinopathy, proliferative vitreoretinopathy, subretinal macular hemorrhage, or macular pucker was performed. The following specific maneuvers were performed with PEAK-fc: transection of epiretinal membranes, retinotomies, retinal vessel coagulation, and posterior membranectomy. RESULTS: Detached and attached retina could be dissected successfully in eight cases. Intraoperatively, incision edges were sharply demarcated, showing no visible collateral damage. Deeper layers than the neurosensory retina were not affected. With the bimanual approach, epiretinal avascular and vascular membranes could be removed in 10 cases. Hemorrhages occurring during transection of vascularized membranes could be stopped immediately using the coagulation mode of PEAK-fc. Posterior capsule fibrosis was successfully excised in one patient. No complications were observed. CONCLUSION: PEAK-fc offers precise and tractionless tissue cutting during ocular surgery. Using different waveform parameters, the same device performs cold cutting and/or "hot" coagulation, thus improving the precision, safety, and ergonomics of vitreoretinal surgery.

Aged↗
PubMedDate not supplied

Five-year follow-up of macular hole surgery with peeling of the internal limiting membrane: update of a prospective study.

PURPOSE: To report on long-term results of macular hole surgery with peeling of the internal limiting membrane (ILM) in a prospective nonrandomized study. METHODS: Sixty-four consecutive patients with a follow-up of at least 36 months were included. Only idiopathic macular holes were included in the study. All patients had undergone standard pars plana vitrectomy with removal of the ILM and intraocular gas tamponade with a 15% hexafluoroethane (C2F6) gas-air mixture followed by a face-down position for at least 5 days. During each follow-up visit, complete clinical examination including determination of best-corrected visual acuity, Goldmann perimetry, and optical coherence tomography was performed. RESULTS: Fifty-two patients were female and 12 were male, and the patients' mean age was 72 years (range, 53-82 years) at the last visit. We observed stage 2 holes in 5 patients, stage 3 holes in 47, and stage 4 holes in 12. The median postoperative follow-up was 62 months (mean, 56 months; range, 36-75 months). Sixty-two patients (97%) were pseudophakic at the last examination: 3 patients (5%) were already pseudophakic at the time of macular hole surgery; a combined procedure was performed on 9 patients (14%); and 50 patients (78%) underwent cataract surgery later. The median follow-up for patients after cataract extraction was 61 months (mean, 56 months; range, 36-75 months). Anatomical closure was achieved in 61 (95%) of 64 patients as confirmed clinically and by optical coherence tomography. No late reopening of a macular hole or formation of epiretinal membranes was observed after successful hole closure. Best-corrected visual acuity improved in 59 (92%) of 64 patients, remained unchanged in 2, and deteriorated in 3. Best-corrected visual acuity improved from a median of 20/100 preoperatively to a median of 20/32 postoperatively (P < 0.001). There was a median gain of 5 lines (range, -6 to 12). The development of visual acuity did not depend on the duration of symptoms, the number of surgeries, or the stage of the macular hole. CONCLUSIONS: Macular hole surgery with peeling of the ILM is a very safe procedure, even in the long term. It leads to very good and stable functional and anatomical results.

Aged↗
PubMedDate not supplied

Short-term in vivo evaluation of novel vital dyes for intraocular surgery.

PURPOSE: To evaluate the staining characteristics and safety of potential new dyes for intraocular surgery in porcine eyes. METHODS: Four dyes in different solutions (light green SF yellowish [LGSF]: 2%; copper(II) phthalocyanine-tetrasulfonic acid [E68]: 2% and 0.5%; bromophenol blue [BPB]: 2%, 1%, and 0.2%; and Chicago blue [CB]: 2% and 0.5%) were included in this investigation. All dyes were dissolved and diluted using balanced salt solution (BSS plus; Alcon Laboratories, Inc., Fort Worth, TX). After triamcinolone-assisted vitrectomy on 10 porcine eyes in vivo, the dyes were first injected into the air-filled vitreous cavity. After 1 minute, the dye was removed by irrigation with BSS, and the staining effect was graded by two examiners. After vitrectomy, the same dyes and concentrations were injected in the air-filled anterior chamber to stain the lens capsule of the same eye. After surgery, the eyes were enucleated and underwent fixation for light and electron microscopy. The animals were killed by injection of pentobarbital (50 mg/kg). For controls, each BSS plus alone and indocyanine green 0.5% were applied in one eye. RESULTS: On the retinal surface, bright staining of the retinal surface was seen after application of BPB 2% and 1%. The staining effect was less pronounced but still very good using E68 2%, and CB 2% and weak using BPB 0.2%, E68 0.5% and CB 0.5% as well as indocyanine green 0.5%. No staining of the retinal surface but of the vitreous was seen after application of LGSF 2%. The lens capsule stained very well with E68 2%, CB 2% and 0.5%, and BPB 2%, 1%, and 0.2% but not with LGSF. No histologic abnormalities were seen after the application in any eye after dye injection. No dye-related complications occurred during surgery. CONCLUSION: In this study, we identified three dyes with satisfying staining characteristics in both anterior and posterior segments. Because BPB stained the retinal surface and lens capsule at a low concentration (0.2%) with no signs of toxicity, this dye seems to be the most promising candidate for application in humans.

Animals↗
PubMedDate not supplied

Intravitreal bevacizumab (Avastin) therapy for persistent diffuse diabetic macular edema.

PURPOSE: To evaluate the efficacy of bevacizumab (Avastin; Genentech, Inc., South San Francisco, CA) for the treatment of diabetic macular edema. METHODS: This prospective, consecutive, noncomparative case series included 51 consecutive patients (26 females and 25 males; mean age, 64 years) with diffuse diabetic macular edema. Inclusion criteria were determined independently of the size of edema, retinal thickness, visual acuity, age, metabolic control, type of diabetes, or previous treatments beyond a 6-month period. At each visit, patients underwent complete eye examination, including determination of best-corrected visual acuity, slit-lamp examination, intraocular pressure measurement, stereoscopic biomicroscopy of the macula, retinal thickness measurement by optical coherence tomography, fluorescein angiography, and fundus photography. After written informed consent was obtained, all patients were treated with a 0.05-mL injection containing 1.25 mg of bevacizumab. RESULTS: All patients completed 6 weeks of follow-up; 23 (45%) completed 12 weeks of follow-up. Sixteen patients (70%) had received at least two intravitreal injections. All patients had undergone previous treatments, such as focal laser therapy (35%), full-scatter panretinal laser therapy (37%), vitrectomy (12%), and intravitreal injection of triamcinolone (33%). The mean diameter of the foveal avascular zone was 503 micro m, with 49% with values of >500 micro m. At baseline, mean visual acuity +/- SD was 25.88 +/- 14.43 ETDRS letters (0.86 +/- 0.38 logMAR of Snellen letters). Mean central retinal thickness by optical coherence tomography +/- SD was 501 +/- 163 micro m (range, 252-1,031 micro m). Mean visual acuity +/- SD increased to 0.75 +/- 0.37 logMAR of Snellen letters at 6 weeks after injection (P = 0.001), with some regression to 0.84 +/- 0.41 logMAR of Snellen letters after 12 weeks. Changes in ETDRS letters were not significant throughout follow-up. Mean retinal thickness +/- SD decreased to 425 +/- 180 micro m at 2 weeks (P = 0.002), 416 +/- 180 micro m at 6 weeks (P = 0.001), and 377 +/- 117 micro m at 12 weeks (P = 0.001). Changes of retinal thickness and visual acuity correlated weakly (r = -0.480 and P = 0.03 at 6 weeks; r = -0.462 and P = 0.07 at 12 weeks). The increase of visual acuity after 6 weeks as measured by ETDRS charts could be predicted best by baseline visual acuity. No other factors investigated, such as age, thickness by optical coherence tomography, or previous treatments, were predictive for the increase in visual acuity. CONCLUSION: Even in cases of diffuse diabetic macular edema not responding to previous treatments such as photocoagulation, intravitreal injection of triamcinolone, or vitrectomy, improvement of visual acuity and decrease of retinal thickness could be observed after intravitreal injection of bevacizumab. Although our follow-up period was too short to provide specific treatment recommendations, the short-term results encourage further prospective studies with different treatment groups and longer follow-up.

Adult↗