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C Eckardt

Publications and source records attributed to C Eckardt.

At least 19 recordsLinked to original sources
PubMed2002

[Retropupillary fixation of the iris claw lens in aphakia. 1 year outcome of a new implantation techniques].

INTRODUCTION: There are several surgical options available for the correction of aphakia. We investigated if retropupillary fixation of an iris claw lens is a method combining the advantages of posterior chamber implants with a new low-risk method of intervention. PATIENTS AND METHODS: An iris claw lens was implanted in 48 eyes in the plano-convex direction (model 205 Y). For the calculation of the IOL power we estimated an A-constant of 116.8. The lens was pushed via a 5-mm wide corneal incision vertically in the anterior chamber and was fixed in the retropupillary position after turning in the horizontal direction. After aspiration of the viscoelastica the corneal incision was closed by a 10-0 nylon suture. RESULTS: The implantation was successful in all patients. A visual improvement was noted in 27 patients (56.2%), an unchanged visual acuity was seen in 18 patients (37.5%) while 3 patients (6.2%) showed a loss of visual acuity. A cystoid macular edema was found by fluorescein angiography in two cases. Leakages in the area of the enclavation were not seen. SUMMARY: The retropupillary fixation of an iris claw lens seems to have the advantages of a true posterior chamber implantation with a low intra- and postoperative risk profile. The easy implantation process with this technique could replace the normally applied sclera suture fixed implantation of a posterior chamber lens as the method of choice.

Aphakia↗
PubMed2001

[Combined cataract-glaucoma surgery with deep sclerectomy. An alternative to gonio-trephination in the intra- and early postoperative phases].

BACKGROUND: We examined the value of deep sclerectomy combined with phacoemulsification as a surgical technique in the peri- and postoperative phases. MATERIALS AND METHODS: Deep sclerectomy with phacoemulsification was carried out in 18 patients. Mean postoperative follow-up was 7.5 weeks. RESULTS: Deep sclerectomy was more difficult to perform than goniotrephination. We observed neither fibrin reaction nor hypotonic dysregulation (intraocular pressure, IOP, < 8 mmHg). Five patients required additional pressure-lowering drugs during postoperative IOP regulation. CONCLUSION: We consider the low inflammatory response in the early postoperative phase to outweigh the greater surgical difficulty and prolonged surgery time. Further studies must verify whether higher IOP during the early postoperative phase is sufficient for good long-term IOP regulation.

Anterior Chamber↗
PubMed2001

Macular translocation: unifying concepts, terminology, and classification.

PURPOSE: To describe some unifying concepts, terminology, and classification of macular translocation so as to facilitate communication within the scientific community. METHODS: A panel of ophthalmologists with expertise in macular translocation reviewed available data and developed some unifying concepts, terminology, and classification of macular translocation. RESULTS: Macular translocation may be defined as any surgery that has a primary goal of relocating the central neurosensory retina or fovea intraoperatively or postoperatively specifically for the management of macular disease. It may be classified according to the size of the retinotomy and, where applicable, the technique of chorioscleral shortening used. The direction of macular translocation is denoted by the movement of the neurosensory macula relative to the underlying tissues. Effective macular translocation may be defined as successful intraoperative or postoperative relocation of the fovea overlying a subfoveal lesion to an area outside the border of the lesion. The concepts of minimum desired translocation and median postoperative foveal displacement can give some useful idea of the likelihood of effective macular translocation before surgery. CONCLUSIONS: Use of a common standardized terminology for macular translocation will facilitate communication within the scientific community and enhance further research in this area. However, the definitions, terms, classification, and concepts concerning macular translocation are likely to continue to evolve as macular translocation undergoes further modifications and refinements.

Humans↗
PubMed2001

In the mammalian eye type VI collagen tetramers form three morphologically different aggregates.

The organization of the aggregates occurring in the stroma: (1) of the murine and human cornea after incubation in an ATP acidic solution; (2) of surgically excised epiretinal membranes (ERM); and (3) of the trabecular meshwork of monkey eyes was investigated morphologically and immunocytochemically on thin section electron microscopy. Morphology. The aggregates in the cornea appeared as cross-banded fibrils. The bands were uniformly electron dense (single banded form); they were separated from each other by interbands consisting of a bundle of filaments emerging in cross section as small areas of randomly assembled dot-like structures. In the ERM, most of the aggregates stood out as heteromorphic cross-banded bodies showing dense bands with electron denser borders (double banded form) and interbands composed of longitudinally oriented, parallel sheets or laminae of amorphous material enclosing thin, similarly oriented filaments. These extended, thinner and double in number (since interlacing with similar components of the opposite sheet), into the pale central zone of the dense band. The aggregates of the trabecular meshwork were heteromorphic, had uniformly dense bands (single banded form as in the cornea), but their interbands displayed longitudinal sheets (as the ERM aggregates). Immunocytochemistry revealed type VI collagen in the three eye aggregates with gold particles preferentially localized at the interbands. The specificity of the antibodies used was tested by Western blot analysis of type VI collagen samples extracted from human placenta and on homogenates of human cornea. In conclusion, the results indicate that the tetramers of type VI collagen may aggregate differently into structures with distinct supramolecular arrangements. These are illustrated in schematic drawings.

Aged↗
PubMed2001

Membrana limitans interna and epiretinal membrane lying on macular holes. Some morphological observations.

The structure of the membrana limitans interna (MLI) in the region of the macula has been investigated by electron microscopy in (a) 2 enucleated human adult eyes and (b) 38 surgically removed samples associated with an epiretinal membrane (ERM). In the enucleated eye, the glia cells were vitrad bordered either by the lamina rara or, directly, by the lamina densa. Both extended into a coarse network whereby the lamina densa, through repeated branches and anastomoses, delimited large meshes, the lamina rara formed their contents. High magnification revealed that both meshes and contents of this network were composed by a further, finer network. It is suggested that strips and small openings of the finer network are homologous to the cords and intercordal spaces, respectively, which have been indicated as the common, basic structures of most of the basement membranes. The MLI excised with an ERM had the same structure. In some of the ERM associated with a macular hole, myofibroblasts prevailed among the cells. They showed indented nucleus, stress fibers abuting on the plasma membrane or in apparent continuity with bundles of extracellular filaments (microtendons), gap junctions. The cells lay on or were surrounded by a discontinuous basement membrane.

Aged↗
PubMed1999

Macular rotation with and without counter-rotation of the globe in patients with age-related macular degeneration.

BACKGROUND: Macular rotation to treat exudative age-related macular degeneration (AMD) involves translocation of the fovea to a site with intact retinal pigment epithelium. To avoid the inevitable postoperative cyclotropia we combined this procedure with torsional muscle surgery. PATIENTS AND METHODS: In 30 eyes the macula was rotated upward by 30-50 degrees following complete artificial retinal detachment and a 360 degrees retinotomy. Simultaneous torsional muscle surgery was not carried out in the first 8 eyes; in the remaining 22 eyes surgery of the oblique muscles was performed alone or in combination with surgery of two or four rectus muscles. Simultaneously or later, muscle surgery was performed on the fellow eye in 17 of these patients. Three of the eight patients who had no primary muscle surgery were operated on later. They had muscle surgery on the macular-rotated eye and on the fellow eye. RESULTS: Postoperatively, the silicone oil was removed from all but one eye and an intraocular lens implanted in all but two eyes. Five eyes developed a postoperative retinal detachment, three of them with proliferative vitreoretinopathy. Three other eyes developed a recurrence of the choroidal neovascularization. At last examination, 18 of the 30 eyes (60%) had a near vision of 0.4 or better, sufficient for the reading of normal newsprint. Six of the eight patients who did not undergo muscle surgery reported considerable disorientation caused by the postoperative diplopia and cyclotropia. The muscle operation, which has been performed in a total of 25 patients, conferred complete freedom from complaints in all but one patient. CONCLUSION: Macular rotation succeeded in restoring reading vision in about half of cases of exudative AMD, at least in the short term. The most serious complication was the development of a retinal detachment. The extremely disorienting side effects of diplopia and tilted image could be prevented or effectively treated by muscle surgery for counter-rotation of the globe, if need be also in the fellow eye.

Aged↗
PubMed1998

[Orthoptic problems after macular rotation with and without muscle surgery].

BACKGROUND: In spite of new therapeutic approaches the treatment of age related macular degeneration remains unsatisfying. Macular rotation is so far only a rarely employed surgical procedure, where the macula is translocated to an area with intact retinal pigment epithelium. The aim of this study was to elucidate the orthoptic problems of macular rotation and describe possible treatment modalities. PATIENTS AND METHOD: Between February and July of 1997 a macular rotation was performed in 8 patients with exsudative macular degeneration, followed by silicone oil removal and implantation of an intraocular lens. In 3 out of 8 patients the oblique muscles were transposed at the beginning of the surgery to produce an excylotropia. In all patients visual acuity for distance and near was determined pre- and postoperatively along with a complete orthoptic status including measuring of cyclotropia. Mean postoperative follow-up was 5.5 months. RESULTS: Due to the unilateral ectopia of the macula all patients presented with a postoperative strabismus with vertical deviation of 2 degrees to 10 degrees. The change of the visual axis resulted in a displacement of the pupillary reflex. The patients described a cyclotropia of 12 degrees to 45 degrees corresponding to the ophthalmoscopically estimated angle of retinal rotation. Patients after surgery of the oblique muscles showed less cyclotropia with an angle of 12 degrees to 20 degrees. They were less disturbed by diplopia and tilted visual impression than those without muscle surgery. All patients exhibited an abnormal head position with chin up and tilt to the side of the operated eye. CONCLUSION: Macular rotation always causes diplopia because of the unilateral ectopia with cyclotropia and vertical deviation. These problems can be considerably reduced by combining macular rotation surgery with oblique muscles surgery. It may well be that in the future these problems can be completely resolved by additional surgery on the rectus muscles.

Aged↗
PubMed1997

[Obtaining donor corneas without eyeball removal].

The goal of the present study was to compare the quality of 7-mm corneal buttons taken directly from donor eyes with commonly obtained transplants. Seven-mm porcine corneal specimens and 16-mm cornoscleral specimens were immersed for 3 and 7 days in Optisol culture medium. After 3 days, ultrasonic pachometry revealed a decline to 73% of the original thickness in the 7-mm and to 83% in the 16-mm specimens. After 8 days, the thickness in both groups had returned to 91% of the original values. Light microscopy revealed a homogeneous endothelial layer in both groups. Staining with 0.25% Trypan blue revealed only a few dead cells. The 7-mm specimens exhibited fewer wrinkles in Descemet's membrane than the 16-mm specimens. Scanning electron microscopy of human 7-mm corneal specimens, some obtained directly from donor eyes and stored in Optisol and some trephined from 16-mm corneoscleral specimens after immersion, detected uniformly smooth cutting edges in both groups. Even the endothelia displayed no marked differences. Our results show that the quality of donor specimens removed at the desired size in situ and stored in Optisol equals that of commonly obtained specimens. Further investigations must show the feasibility of this procedure in practice.

Animals↗
PubMed1997

[Removal of the internal limiting membrane in macular holes. Clinical and morphological findings].

UNLABELLED: The recommended treatment for full-thickness macular holes is removal of the posterior hyaloid and sometimes the epiretinal membrane from the retina during vitrectomy in order to release the assumed intravitreous traction. We have employed a technique involving the additional removal of the membrana limitans interna (MLI) from the retina in the vicinity of the macular hole. We report on our clinical results and ultrastructural findings. MATERIALS AND METHODS: Between December 1995 and July 1996, we performed vitrectomies on 39 eyes of 37 patients with full-thickness macular hole. After removal of the attached posterior hyaloid, a specially developed forceps was used to remove a circular area of the MLI approximately three to four disc diameters in size. At the conclusion of the operation, 20% C3F8 gas was injected and the patient instructed to stay in a prone position for 8 days. RESULTS: Intraoperatively, "rhexis" of the MLI only rarely produced bleeding or recognizable retinal edema. Complete closure of the hole was observed postoperatively in 36 of the 39 eyes (92%). A visual improvement of at least two lines was achieved in 77% of eyes with successful closure. Pigment irregularities or edematous changes could not be detected either clinically or by fluorescein angiography in any of the 39 eyes. Electron microscopy was performed on 23 of the membranes. The salient feature was the MLI. Canals leading from the inner to the outer surface of the MLI contained Müller cell processes with clear signs of necrosis or degeneration. On the vitreous side, the MLI usually exhibited myofibroblasts. CONCLUSIONS: The MLI was successfully removed in all 39 eyes with a full-thickness macular hole. This procedure led to very good anatomic and functional results. It remains for future studies to determine the pathogenic significance of the necrotic processes detected by electron microscopy in the MLI canals.

Adult↗
PubMed1997

[Incidence of posterior vitreous detachment in the elderly].

UNLABELLED: Few studies have so far investigated the frequency of posterior vitreous detachment in healthy eyes, and most of these have been biomicroscopic investigations. Since the reported data sometimes vary widely, especially in older age-groups, we conducted sonographic investigations on the frequency of posterior vitreous detachment in old and very old patients. METHOD: A total of 712 eyes in 404 patients aged 65 years and older were studied. Eyes that had previously been operated on, eyes with proliferative retinal disease, and eyes with an ametropia exceeding +/- 3.0 diopters were excluded from the study. The vitreous body was investigated using kinetic B-mode sonography. It was classified as completely attached, completely detached, or partially detached. RESULTS: In the 65- to 69-year-old age-group, only 12 of 105 eyes (11%) exhibited a complete posterior vitreous detachment, while the vitreous body was still completely attached in 75 eyes (71%). A marked decline in the number of eyes with a completely attached vitreous body was first seen in the 80- to 89-year-old age-group. Even in this group, however, the vitreous body was still completely attached in 114 of 263 eyes (43%), whereas it was partially detached in 28 eyes (11%). Only in 121 eyes (46%) was the vitreous body completely detached. CONCLUSIONS: The frequency of partial or complete posterior vitreous detachment increases with age. However, posterior vitreous detachment in the elderly is rarer than previously thought.

Aged↗
PubMed1997

Diathermy capsulotomy to remove fibrotic anterior capsules in pseudophakic eyes.

OBJECTIVE: To evaluate a technique for removing fibrotic tissue of a shrunken opening of the anterior capsule. SETTING: Augenklinik der Städtischen Kliniken, Frankfurt, Germany. METHODS: Intraocular diathermy was used to enlarge the anterior capsule in nine patients with intraocular lenses (IOLs) (eight poly[methyl methacrylate], one silicone). In five patients, the diathermy was done to improve the intraoperative fundus view just before vitreoretinal surgery. The other four patients had visual field impairment or IOL dislocation resulting from capsular opening contraction. A 1.1 mm paracentesis was made and a viscoelastic injected beneath the anterior capsule. The diathermy probe was then introduced into the anterior chamber and the capsule opening cut to the desired size. The excised material was removed with a forceps. RESULTS: The procedure was free of complications. No eye developed a postoperative inflammatory reaction. CONCLUSION: Diathermy was easy to perform and according to these preliminary results, highly effective.

Adult↗
PubMed1996

[Surgical removal of submacular neovascularization membranes].

UNLABELLED: New techniques for vitreoretinal surgery enable the removal of submacular neovascular membranes inaccessible to laser coagulation. The present study describes the anatomical and functional results following membrane removal. PATIENTS: Between January 1994 and June 1995, submacular neovascular membranes were removed from 56 eyes with age-related exudative macular degeneration. Thirty-one eyes had classic subfoveal membranes; 19, occult membranes; and 6 eyes, disciform fibrotic changes that had already persisted for more than 6 months. RESULTS: Surgery led to improved vision in 20 of the 56 eyes (36%). In 26 of the 56 eyes (44%) vision at the last follow-up was no different from preoperative vision: in 10 eyes (17%) visual acuity declined. In the group of 6 eyes with a 6-month history of exudative maculopathy, surgery produced a slight improvement in vision in most patient. Complications arose in 8 of the 56 eyes (14%), namely choroidal hemorrhage (2 eyes), a macular hole (1 eye), and peripheral retinal detachment (5 eyes). Recurrence of the membrane was seen in 5 eyes (9%). CONCLUSION: Surgical removal of submacular membranes can often lead to stabilization or even improvement of vision. Owing to the relatively high rate of complications, however, the indications must be rigorously appraised on a case-by-case basis.

Aged↗
PubMed1996

[Outcome of corneal astigmatism after pars plana vitrectomy with or without simultaneous cataract extraction].

Changes in corneal astigmatism induced by pars plana vitrectomy (PPV) (group I, 44 eyes) and PPV combined with no-stitch cataract surgery (group II, 20 eyes) were studied prospectively for a period of at least 3 months. The amount and orientation of the keratometric cylinder and the surgically induced astigmatism (according to the methods of Jaffe and Clayman or Naeser) were analysed. In the first postoperative week both groups exhibited a marked against-the-rule to oblique astigmatism (in group I up to 3.65 +/- 1.40 D, in group II up to 3.05 +/- 1.60 D, according to Jaffe). After 3 months this had declined in group I to 0.40 +/- 0.27 D, whereas a slight induced astigmatism (0.97 +/- 0.41 D) persisted in group II. Gas endotamponade did not significantly aggravate the postoperative astigmatism in either group. Computerized video-keratography generally revealed an asymmetric bowtie pattern during the first week. Our results show that PPV alone induces no appreciable long-term corneal astigmatism. Optical rehabilitation, however, can be delayed by a marked short-term postoperative astigmatism. PPV with simultaneous no-stitch cataract surgery, by contrast, was found to induce a persisting slight astigmatism against the rule.

Adult↗
PubMed1995

[Binocular vision in idiopathic macular foramen. Pre- and postoperative findings].

In recent years idiopathic macular hole has become an increasingly frequent indication for vitrectomy. To our knowledge, the literature contains no studies comparing binocular vision before and after vitrectomy. We therefore carried out a prospective study not only on visual acuity following vitrectomy but also, for the first time, on binocular vision. Stereopsis and fusion were evaluated in 37 patients with idiopathic macular holes (stage I-IV) using Bagolini striated glasses, the Titmus stereotest (contour stereopsis), the random dot test (global stereopsis), the Worth four-dot test and the phase-difference haploscope. The tests were performed preoperatively and 10-12 weeks after vitrectomy. Two patients with stage I macular hole showed no loss of stereopsis in conventional tests. One patient, however, exhibited suppression tendencies with partial exclusion. The 18 patients with stage II macular hole had a relative good visual acuity of 0.2-0.6, but subnormal binocular vision with marked suppression of foveal images. Postoperatively, the majority of these patients had symptom-free binocular vision and good stereopsis. Some, however, continued to experience foveal exclusion. Patients with macular hole stage III and IV (n = 17) had the poorest results. Although the postoperative visual acuity improved by 2 to 3 points in some patients (n = 6), in approximately one third it remained limited to global peripheral binocular vision. In summary, our findings show that even in early stages (I and II), macular hole can cause not only reduced visual acuity but also impairment or, in stage II, even loss of binocular vision. Vitrectomy in these early stages often leads to an overall improvement in visual acuity and binocular vision, whereas in more advanced stages vitrectomy often does not affect visual acuity and binocular vision. This should be taken into account when weighing up the indications for surgery.

Aged↗
PubMed1995

[Toxic substances with silicone oil after intraocular injections].

In articles about the analysis of intraocular silicone oil, mostly the amount and toxicity of low-molecular-weight components (LMWC) have been investigated. This study was intended to analyze the components of silicone oil following a longer intraocular application. We analyzed silicone oil removed from human eyes with PVR a few months postoperatively. The fraction of LMWC was further investigated and we separated 16 different components belonging to hexachlorhexanes (HCH), polybiphenyls (PCB) and dichlor-diphenyl-trichlorethane (DDT). All these substances are said to have a toxic and cancerogenic effect as well as weakening the immune system. The concentration of these organic chloride components measured in intraocular injected silicone oil is about the same as fatty tissue but exceeds the concentration in human blood enormously. Possible damage to the retina by these toxic substances is another reason for early removal of silicone oil if the situation of the retina is stable.

Adolescent↗
PubMed1993

[Results of pars plana vitrectomy in chronic uveitis in childhood].

During 1986-1991 vitreous surgery was performed in 5 girls and 8 boys (age range 2-15 years) with chronic uveitis. In 6 cases a combined lensectomy-vitrectomy was performed because cataract was present, so that the results generally refer to 19 eyes. We found a low rate of postoperative complications. During a follow-up period of 6 months to 5 years (average 2 years and 1 month), 12 of the 19 eyes showed a significant visual improvement. Preoperatively, 8 eyes were found to be affected by cystoid macular edema; in 7 of these cases remarkable regression of the edema was observed after surgery. In two-thirds of cases the intensity of the inflammation decreased, so that the dose of corticosteroids could be reduced postoperatively. Our results suggest that vitrectomy for chronic uveitis in children is a relatively safe and successful treatment. In order to prevent irreversible complications and amblyopia surgery should be performed in an early stage of the disease.

Adolescent↗