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D von Domarus

Publications and source records attributed to D von Domarus.

At least 19 recordsLinked to original sources
PubMed2002

[In vivo measurement of temperature during phacoemulsification].

BACKGROUND: Based on our experience of in vitro measurements of temperature in the anterior chamber in 1994 we designed a new spatula with an integrated probe that enabled us to measure temperature continuously during phacoemulsification without any surgical effort. METHODS: We measured the temperature in the anterior chamber during 50 cases of phacoemulsification. Depending on the indications, we used different energy modes (0-100%) and pulse modes ranging from 3 to 10 pulses per second or continuous ultrasonic output. Different viscoelastic substances were also used. RESULTS: The average temperature in the anterior chamber was 30 degrees C and adapted to the temperature of the irrigation fluid within seconds as soon as irrigation was started. During phacoemulsification each ultrasonic output causes an increase of temperature. In the case of continuous mode, the maximum rise in temperature was 3.5 degrees C. When the pulse mode was used the temperature increased up to 1.7 degrees C. It is important to note that one single pulse may increase the temperature by 0.8 degree C close to the phacotip. The rise of temperature correlated with the viscosity of the viscoelastic substance used. CONCLUSIONS: The new probe proved to be a practical device to monitor temperature in the anterior chamber during phacoemulsification. Up to now we did not encounter any critical degrees of temperature but it should be pointed out that a functional irrigation unit, the use of pulse mode or permanent ultrasonic output and in particular the type of viscoelastic material used are all important parameters influencing the rise of temperature during phacoemulsification. Further experience and results obtained with the new probe will be reported in the future.

Anterior Chamber↗
PubMed2002

[Final clinical indications and etiology in 1,023 enucleations. Descriptive databank evaluation with SPSS software in variable response mode with dummy variables].

BACKGROUND: A new data bank developed for ophthalmopathology using a computer-generated, multidigital data code is expected to be able to accomplish complex clinicopathologic correlations of diagnoses and signs, as provided by (multiple) clinical events and histopathologically proven etiologies, and to facilitate the documentation of new data. PATIENTS AND METHODS: In the ophthalmopathology laboratory 2890 eyes were examined between January 20, 1975 and December 12, 1996. The main diagnoses and patient data from this 22-year period were recorded. To facilitate the presentation of data, a 10-year period with eyes of 976 patients enucleated from December, 1986 to December, 1996 was chosen. Principal and secondary diagnoses served for establishing the data bank. The frequencies of successive histologic and clinical diagnoses were evaluated by a descriptive computing program using an SPSS-multi-response mode with dummy variables and a categorical variable listing of the software (SPSS version 10.0) classified as (a) non-filtered random, (b) filtered by multiple etiologies, and (c) filtered by multiple events. RESULTS: The principal groups (e.g., histologic diagnoses concerning etiology) and subgroups (e.g., trauma, neoplasia, surgery, systemic diseases, and inflammations) were defined and correlated with 798 separate diagnoses. From 11 diagnoses/events ascribed to the clinical cases, 11,198 namings resulted. CONCLUSIONS: Thus, a comparative study of complex etiologies and events leading to enucleation in different hospitals of a specific area may be performed using this electronic ophthalmopathologic data bank system. The complexity of rare disease and integration into a superimposed structure can be managed with this custom-made data bank. A chronologically and demographically oriented consideration of reasons for enucleation is thus feasible.

Causality↗
PubMed2000

[Long-term results of combined glaucoma and cataract surgery. Intraocular pressure and visual acuity follow-up].

BACKGROUND: The aim of this investigation was to ascertain the long-term results of intraocular pressure and visual acuity after combined glaucoma and cataract surgery. PATIENTS AND METHODS: Between 1994 and 1997, 65 eyes underwent Pham's sclerectomy and at the same time 65 eyes underwent Elliot's trephination with scleral flap. Both procedures were combined with phacoemulsification and implantation of a posterior chamber lens. The mean follow-up was 21.9 +/- 11.0 months. RESULTS: The IOP of eyes that underwent Pham's sclerectomy decreased from 21.4 +/- 3.3 mmHg to 14.9 +/- 2.7 mmHg and of eyes that underwent Elliot's trephination from 24.6 +/- 7.3 mmHg to 15.8 +/- 2.6 mmHg. Thirty percent of the eyes with Pham's sclerectomy and 25% with Elliot's trephination required an additional medication. In both procedures the overall visual acuity increased by three lines. CONCLUSIONS: These results of combined glaucoma and cataract surgery confirm their efficiency. From the economical aspect, combined glaucoma and cataract surgery has gained increasing significance.

Aged↗
PubMed1999

Tapioca melanomas of the iris: immunohistology and report on two cases.

BACKGROUND: Tapioca-like tumors are rare, and their benign or malignant nature is obscure without histological work-up. We report on the clinical and histological features of different types of tumors in two patients. CASE REPORT: Two patients aged 17 and 45 years presented with brownish iris masses increasing in size. Full-thickness en bloc excision of melanocytic tumors (5.5 mm and 7.0 mm in diameter) was carried out. Histological work-up revealed a nevus cell nevus in the young patient and an epithelioid malignant melanoma in the middle-aged patient evolving from the ciliary body. Staining for HMB-45 was marked in both tumors, for S-100 low in the nevus and marked in the melanoma, and for p53 negative in the nevus and positive in the melanoma. Ki67 stains were negative. CONCLUSION: We propose that excision of anteriorly located pigmented tumors that increase in size is indicated in order to determine whether they are benign or malignant. In these case reports, tapioca-like tumors include a benign and a malignant entity. To our knowledge, a nevus cell nevus presenting as a tapioca-like tumor has not previously been described. Curative surgery and histological and immunohistological evaluation are required to characterize the malignant potential of these tumors and the prognosis.

Adolescent↗
PubMed1998

[Clinical and histopathological aspects of 113 necrotizing malignant melanomas of the choroid. 1. Clinical and histological features of necrotizing choroidal melanomas].

BACKGROUND: Tumor necrosis may reflect a destructive immune reaction. Systematic and statistically significant comparative clinico-histopathologic studies have not yet been reported. PATIENTS AND METHODS: 113 necrotizing choroidal melanomas (NCM) recruited from 701 enucleated globes 1967-1988 were resectioned, stained and compared to 100 choroidal melanomas without necrosis (CM), and data of 74 patients with a follow-up of more than 10 years were evaluated. RESULTS: Statistically significant characteristics of NCM were: patient age < 60 yrs. for NCM 27.4%, CM 46%; patient age in men for NCM was 64 yrs on average (CM: 58 yrs.), in women for NCM 67 yrs. (CM: 59 yrs.). Time elapsed between first symptoms and enucleation was < 12 months in 15.9% of NCM (89% for CM), and > 12 months in 23.9% of NCM (11% in CM). Mixed or epitheloid cell tumors was seen in 54.9% of NCM and 49% of CM, spindle cell tumors in 36.3% of NCM and 51% in CM. Advanced tumor stages T3 and T4 were present in 45.1% resp. 36.3% of NCM compared to 37% resp. 16% in CM. Scleral invasion was documented in 67.3% of NCM and 37% of CM, extrascleral dissemination in 43% of NCM and 16% of CM. Secondary glaucomas were seen in 62.2% of NCM and 6% CM, a penetration through Bruch's membrane in 61.0% of NCM and 46% of CM. Intratumoral hemorrhage was noted in 68.14% of NCM and 24% of CM, extratumoral bleeding in 23.9% of NCM and 0% CM. Inflammatory reactions in tumors were observed in 96.7% of NCM harboring > 30% necrosis compared to 5% in CM, and extratumoral in 94.5% of NCM and 0% of CM. Intraocular extratumoral necrosis was seen in 23.9% of NCM and 0% of CM. There were no significant differences in the degree of pigmentation of the 90.3% pigmented NCM or of the 94% pigmented CM, neither in the tumor localization, being constantly behind the equator in 87% of cases. Survival of patients with NCM patients was 5 years and 9 months on average (5-year mortality rate 41.9%), and 74.3% were deceased from metastatic spread. CONCLUSIONS: Significant clinical and histopathological differences between necrotizing and non-necrotizing malignant melanomas of the choroid can be identified. The inflammatory reaction of NCM must be further elucidated, particularly with respect to the nature of tumor-infiltrating lymphocytes.

Adult↗
PubMed1995

[Experimental study of the temperature during phacoemulsification].

UNLABELLED: Reports on thermal burns during phacoemulsification motivated us to perform an experimental study on the temperature gradient [2,7]. A special measurement technique was developed that enable us to record temperatures in 0.1 s and to document these measurements and interpret them. The experiments were conducted in enucleated pig eyes, as well as in a constructed model of the anterior chamber. Using 500 such measurements, we discuss and demonstrate the influence of the volume of the anterior chamber, the adjustment of the phacoemulsification, the presence of viscoelastic material, the reflection of ultrasonic power on the lens, and insufficient or interrupted irrigation and/or aspiration. RESULTS: An analysis of the measurements showed that within 8 s extremely high temperatures developed. At the phacosleeve, temperatures of more than 100 degrees C were recorded. Measurements around the phacotip also showed high temperatures resulting in tissue degeneration, especially with simultaneous application of viscoelastic material and/ or the presence of a hard nucleus. When pulse modulation is applied or power reduced, temperatures drop to less than 50%. CONCLUSIONS: The main factor behind the development of high temperatures is the breakdown of irrigation. The danger of phacoburns increases by application of viscoelastic material, reduced volume of the anterior chamber when there is a hard nucleus and high ultrasonic power with no pulse.

Animals↗
PubMed1991

[Unusual course of hypernephroma metastasis].

11 years after removal of a kidney because of hypernephroma a choroidal metastasis of this tumor grew. Clinically an inflammatory process had been suspected, thus leading to late correct diagnosis. The clinical and histological findings are presented. In the overall statistic of ocular metastasis seen in the university-eye-hospital in Hamburg, hypernephromas hold the 3rd place in the rank-list of the most common primary tumors. Thus, in case of a suspected ocular metastasis, in differential diagnosis a hypernephroma should be excluded.

Aged↗
PubMed1990

[The regression behavior of choroid melanoma following radiotherapy--a new prognostic parameter?].

The present paper reports on follow-up examinations of 246 patients after Ruthenium106 treatment of choroidal melanomas (follow-up time 1.8 to 13 years). In January 1988, 212 patients were alive and free of metastases; 15 had died, 12 of them of melanoma metastases, and 17 could not be followed up. In a retrospective analysis of factors influencing tumor-related mortality, the rate of regression of irradiated tumors was found to be particularly significant. The mean time taken to reduce tumor volume by half was 4.4 months in patients who died of metastases, as against 6.6 months in a matched group of survivors. Using discriminance analysis, the difference was found to be highly significant (P = 0.0058). In the total patient population, a significant correlation was found between pretreatment tumor volume and the probability of metastases (P = 0.058). It may be concluded, though with the qualification that the number of tumor-related deaths was small, that the tumor regression rate is an important factor in the prognosis for patients with Ruthenium-treated malignant choroidal melanomas.

Choroid↗
PubMed1990

Carcinoma in situ of the cornea.

Carcinoma in situ of the cornea is part of a pathological entity, which covers all conjunctival and corneal epithelial neoplasiae (CIN). The clinicopathological characteristics of this rare ocular tumor will be demonstrated.

Adult↗
PubMed1990

[Histopathological findings following cryo-coagulation of the ciliary body with a nitrogen-cooled probe].

A new cryoprobe was investigated in rabbits for experimental coagulation of the ciliary body. In a one-step procedure, the cyclodestructive effect was achieved by cooling the cryoprobe down to -100 degrees C without significant lens damage. The histological investigation showed extensive necrosis of the ciliary epithelium 2 h and 2 days after the freezing damage. After 2 weeks and 2 months, fibrous atrophy of the entire segment of the ciliary body could be observed.

Animals↗
PubMed1989

[Ultrastructural studies of the epithelium in Reis-Bückler's corneal dystrophy].

In Reis-Bücklers' dystrophy an unknown pathomechanism in Bowman's layer and the basal cells of the corneal epithelium results in recurrent epithelial erosions. The final stage is characterized by visual impairment due to irregular astigmatism and opacities in the superficial stroma. The treatment is superficial keratectomy, lamellar or perforating keratoplasty. This study presents the electron-microscopic findings in the epithelium and Bowman's layer from samples obtained from 3 generations of the same family. All were diagnosed and treated in the University Eye Clinic of Hamburg.

Corneal Dystrophies, Hereditary↗
PubMed1988

[Penetrating keratoplasty--indications with special reference to artificial lens keratopathy].

During the period from 1980 until the beginning of 1986, 1,219 corneal buttons removed in the course of penetrating keratoplasty were histologically examined. In 16.5% (201 cases) a re-keratoplasty was necessary. Indications for a primary corneal transplant (n = 1,018) were keratitis-induced corneal changes (35.0%), dystrophies (30.5%), surgical traumas (17.2%), nonsurgical traumas (11.4%), congenital corneal clouding (3.1%) and degenerations (2.8%). Over the six-and-a-half-year period the incidence of pseudophakic bullous keratopathy was 6.9%, with an increase from 1.6% in 1980 to 12.4% in 1986. Besides an unspecific endothelial cell atrophy, fibroblast-like cell structures, possible macrophages, were found in some specimens by histologic examination on corneal buttons as well as on explanted intraocular lenses.

Cornea↗
PubMed1988

Binding of peanut agglutinin on fresh and organ-cultured porcine corneal tissue.

To investigate the binding of peanut-agglutinin (PNA) on porcine corneal tissue, several methods of tissue processing were used. In cryostat sections of postmortem tissue, PNA labeling of epithelial cell membranes was detected. In the stroma, a fibrillar structure parallel to the corneal surface was found. The anterior part of Descemet's membrane was strongly positive, whereas the posterior Descemet membrane was negative. The endothelium was faintly positive. After 3 days of organ culture, the epithelial and endothelial staining patterns were not significantly changed. The stromal fibrils detected by PNA staining showed a considerable spatial disarrangement due to the stromal hydration.

Animals↗
PubMed1988

Clinical picture and problems of keratoplasty in Richner-Hanhart syndrome (tyrosinemia type II).

The Richner-Hanhart syndrome seen in a middle-aged woman is described. The patient had the typical clinical manifestations of tyrosinemia II with a bilateral keratopathy, palmar and plantar hyperkeratosis. The patient was subjected to a specific diet and to perforating keratoplasty. Postoperative systemic therapy with steroids had a negative influence on the clinical manifestations; dendritic lesions which developed on the corneal graft disappeared after interruption of the systemic steroid therapy. This suggests that cortisone treatment after keratoplasty should be avoided in this special metabolic disorder.

Amino Acid Metabolism, Inborn Errors↗
PubMed1987

[Attempt at preoperative differentiation of malignant melanoma of the choroid. A comparison of nuclear magnetic resonance tomography, ultrasound echography and histopathology].

In a large choroidal melanoma (prominence 12 mm, volume approx. 1,900 mm3) diagnostic sonography revealed an unusual compartmentation, corresponding to the internal reflectivity of the tumor. When NMR imaging was performed, marked differences in signal behavior were seen between the tumor's center and its periphery. Histopathology revealed a highly pigmented spindle B melanoma containing an amelanotic island with signs of necrosis. The ultrasound pattern was explained on the basis of well known physical phenomena, whereas the NMR signals are still not fully understood.

Adult↗
PubMed1987

Tissue changes induced by intraocular lenses. A histopathologic study.

The histopathologic findings in autopsy and surgically enucleated eyes are described. Tissue atrophy and inflammatory reaction can be demonstrated in every eye examined in our laboratory. Scanning electron microscopy was used to detect tissue formation on intraoccular lenses.

Atrophy↗