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G O Naumann

Publications and source records attributed to G O Naumann.

At least 19 recordsLinked to original sources
PubMed1999

Adenoma of the nonpigmented ciliary epithelium mimicking a malignant melanoma of the iris.

Adenomas of the nonpigmented ciliary epithelium are rare tumors and are difficult to differentiate from amelanotic malignant melanomas of the ciliary body. We describe a 62-year-old woman with a nonpigmented, vascularized iris tumor with small satellites involving the anterior chamber angle. Clinically, an amelanotic, tapioca, malignant melanoma of the iris was suggested although the blood-aqueous barrier was intact. A block excision of 7.5 mm, a tectonic corneoscleral graft, and a simultaneous extracapsular cataract extraction with implantation of a posterior chamber lens were performed. Histopathologic and electron microscopic studies revealed an adenoma of the nonpigmented ciliary epithelium. Postoperative visual acuity was 20/40 OD after 6 weeks. An adenoma of the nonpigmented ciliary epithelium may mimic an amelanotic malignant melanoma of the iris and should be considered in its differential diagnosis.

Adenoma↗
PubMed1999

Zernike representation of corneal topography height data after nonmechanical penetrating keratoplasty.

PURPOSE: To demonstrate a mathematical method for decomposition of discrete corneal topography height data into a set of Zernike polynomials and to demonstrate the clinical applicability of these computations in the postkeratoplasty cornea. METHODS: Fifty consecutive patients with either Fuchs' dystrophy (n = 20) or keratoconus (n = 30) were seen at 3 months, 6 months, and 1 year (before suture removal) and again after suture removal following nonmechanical trephination with the excimer laser. Patients were assessed using regular keratometry, corneal topography (TMS-1, simulated keratometry [SimK]), subjective refraction, and best-corrected visual acuity (VA) at each interval. A set of Zernike coefficients with radial degree 8 was calculated to fit two model surfaces: a complete representation (TOTAL) and a representation with parabolic terms only to define an approximate spherocylindrical surface (PARABOLIC). The root mean square error (RMS) was calculated comparing the corneal raw height data with TOTAL (TOTALRMS) and PARABOLIC (PARABOLICRMS). The cylinder of subjective refraction was correlated with the keratometric readings, the SimK, and the respective Zernike parameter. Visual acuity was correlated with the tilt components of the Zernike expansion. RESULTS: The measured corneal surface could be approximated by the composed surface 1 with TOTALRMS < or = 1.93 microm and by surface 2 with PARABOLICRMS < or = 3.66 microm. Mean keratometric reading after suture removal was 2.8+/-0.6 D. At all follow-up examinations, the SimK yielded higher values, whereas the keratometric reading and the refractive cylinder yielded lower values than the respective Zernike parameter. The correlation of the Zernike representation and the refractive cylinder (P = 0.02 at 3 months, P = 0.05 at 6 months and at 1 year, and P = 0.01 after suture removal) was much better than the correlation of the SimK and refractive cylinder (P = 0.3 at 3 months, P = 0.4 at 6 months, P = 0.2 at 1 year, and P = 0.1 after suture removal). Visual acuity increased from 0.23+/-0.10 at the 3-month evaluation to 0.54+/-0.19 after suture removal. After suture removal, there was a statistically significant inverse correlation between VA and tilt (P = 0.02 in patients with keratoconus and P = 0.05 in those with Fuchs' dystrophy). CONCLUSIONS: Zernike representation of corneal topography height data renders a reconstruction of clinically relevant corneal topography parameters with a marked reduction of redundance and a small error. Correlation of amount/axis of refractive cylinder with respective Zernike parameters is more accurate than with keratometry or respective SimK values of corneal topography analysis.

Adolescent↗
PubMed1999

Quantification of blood--aqueous barrier breakdown after trabeculectomy: pseudoexfoliation versus primary open-angle glaucoma.

PURPOSE: Impairment of the blood-aqueous barrier in unoperated eyes with pseudoexfoliation syndrome has been demonstrated by fluorescein angiography, fluorophotometry, measurement of aqueous flare, and determination of aqueous protein. We performed noninvasive quantification of aqueous flare using the laser flare-cell meter to compare blood-aqueous barrier breakdown after trabeculectomy in eyes with primary open-angle glaucoma (POAG) and in eyes with pseudoexfoliative glaucoma (PEX). METHODS: Twenty eyes with PEX and 20 eyes with POAG were included in the study. Trabeculectomy was performed by two surgeons according to a standard trabeculectomy technique. Intra- and postoperative treatments were identical in both groups. Aqueous flare was quantitatively determined using the laser flare-cell meter FC-1000 (Kowa, Tokyo, Japan) before and 3, 5, 7, and 9 days after trabeculectomy. Absolute flare and difference between post- and preoperative flare values were statistically analyzed using the Mann-Whitney U-Test for independent samples. RESULTS: Before surgery, aqueous flare values were significantly higher in PEX than in POAG. On days 3, 5, 7 and 9 after surgery, flare values were significantly higher in eyes with PEX than in eyes with POAG. Absolute differences between post- and preoperative flare values also were significantly higher in eyes with PEX, but this was not true for percentage values. CONCLUSION: These results show that substantial blood-aqueous barrier breakdown occurs in eyes with PEX after trabeculectomy. These alterations may contribute to early or late complications of trabeculectomy and indicate the need for close postoperative follow-up evaluation in eyes with PEX.

Aged↗
PubMed1998

Stromal thermal effects induced by nonmechanical (2.94-mum) erbium:YAG laser corneal trephination.

OBJECTIVE: To determine stromal thermal changes after erbium (Er):YAG laser corneal trephination with the use of 2 open masks. METHODS: Corneal trephination was performed in 89 enucleated pig eyes with an Er:YAG laser (400-microsecond pulse duration), 4 open masks (2 metallic and 2 ceramic) for both donors and recipients, and an automated globe rotation device. Different combinations of laser settings were used: pulse energy, 100, 200, and 400 mJ; repetition rate, 2 and 5 Hz; and spot size, 1.3 and 3.2 mm. Thermal effects in corneal stroma and regularity of the cut edges were quantitatively assessed by light microscopy, transmission and scanning electron microscopy. RESULTS: Best regularity and minimal thermal effects of the cut were observed with the use of ceramic masks at 200 mJ, 2 Hz, and 3.2-mm spot size, with middepth thermal changes of 18 +/- 2 microm. Effects increased with cut depth and were lower in donor corneas and with the use of ceramic masks (P<.001). Regularity of the cut was higher in the donors (P = .05) with lower repetition rates (P<.001). CONCLUSIONS: Even with the "free-running" Er:YAG laser mode, features of the trephination cut resembling those created by the 193-nm excimer laser along metal mask were achieved. Ceramic masks may be more suitable than metal masks. The Er:YAG laser seems to have the potential to be a compact and low-cost alternative in nonmechanical trephination for penetrating keratoplasty. CLINICAL RELEVANCE: Thermal effects after corneal trephination with the free-running Er:YAG laser (2.94 mm) are limited and predictable.

Animals↗
PubMed1998

[Endocrine orbitopathy: comparison of the long-term result and classification after radiotherapy].

BACKGROUND: This study compares 4 classifications in patients with progressive refractory Graves orbitopathy (GO) and examines their prognostic value in long-term follow-up. PATIENTS AND METHODS: From 1984 to 1994, 60 consecutive patients (49 female, 11 male) received 20 Gy (10 x 2 Gy) radiotherapy with 6 MV Linac photons. Ocular symptoms and functional impairment was evaluated according to 4 GO-classification systems: Werner-, modified ATA- and Stanford-Score and Ophthalmopathy-Index (OI) according to Grussendorf. In addition, all patients noted their subjective response on a linear scale (0 to 100%). RESULTS: Improvement was achieved within 1 year after radiotherapy according to the Werner-Score in 28 (47%) patients in > or = 1 symptom category, according to the modified ATA-score in 48 (80%), the Stanford-score in 47 (78%) and the OI-Score in 55 (92%) patients (reduction of > 2 points). The Werner-Score correlated less to the other scores (coefficient r < 0.5) than the other scores among themselves (r approximately 0.9). The ATA-Score improved in the different symptom categories between 47% (stage VI) and 87% (stage V). The OI-Score was reduced by a mean of 6 points. The patients reached a mean subjective improvement of +70 +/- 25%. Acute or chronic side effects were not observed. In multivariate analysis the "male gender" (p = 0.08), a "symptom duration prior to radiotherapy > 1 year" (p = 0.14) and a "high symptom category" (p = 0.11) indicated a negative prognostic trend. CONCLUSIONS: External radiotherapy is effective for severe, progressive GO after pretreatment. A minimum follow-up of at least 12 months and standardized classification and success criteria are required.

Adolescent↗
PubMed1998

[Immunologic transplant reactions after non-mechanical corneal trepanation with the excimer laser].

BACKGROUND: Nonmechanical trephination has been established as the standard procedure in penetrating keratoplasty (PK) for avascular corneal diseases at our institution. The purpose of this study was to analyze the incidence and reversibility of immunologic graft reactions after nonmechanical trephination and to detect potentially causative factors. PATIENTS AND METHODS: Out of a total series of 400 nonmechanical PKs, 286 consecutive procedures with sufficient follow-up performed between 07/1989 and 09/1997 were included in the study (104 x keratoconus, 78 x Fuchs' dystrophies, 31 x bullous keratopathies, 28 x ulcers, 25 x avascular scars, 12 x stromal dystrophies, 4 x buphthalmos, 4 x others; 202 x PK only, 84 x combined procedures; 276 first PK). The age of the 138 females and 148 males at the time of surgery ranged from 16 to 89 (mean 55 +/- 19) years. The recipient and donor trephinations were performed from the epithelial side using an 193-mm excimer laser (MEL50 or MEL60, Aesculap-Meditec, 1.5 x 1.5 mm spot mode, 16-24 mJ/pulse, repetition rate 30 or 25/s; metal masks). The shape of the recipient trephination was either circular with four or eight "orientation teeth" (n = 251; 5.0-8.0 mm diameter) or elliptical (n = 35, 6.0 x 7.0 to 7.5 x 8.5 mm diameter). In 62% of procedures fresh or short-term-preserved donor tissue was used, and in 38% of procedures the donor tissue was organ-culture-preserved. RESULTS: During a mean follow-up of 22 +/- 18 months (maximum 7.7 years), 10 acute diffuse (3 irreversible; 1.0%) and 3 chronic focal endothelial graft reactions occurred (4.5%) not earlier than 4 months and not later than 35 months after PK. Elective procedures (3.5%) resulted in significantly (P = 0.01) less reactions than acute corneal ulcers (14.3%). After 1, 2 and 3 years, the cumulative reaction rates (Kaplan-Meier values) were 1.3%, 6.3% and 13.9% in elective procedures, none of which, however, occurred after 26 elliptical trephinations. With fresh or short-term-preserved donor tissue (4.2%), graft reactions did not happen more frequently but earlier (12 +/- 6 months) than with organ-culture-preserved donor tissue (2.2%, 30 +/- 6 months). In patients with keratoconus (4.9%), reactions occurred more frequently (P = 0.05, LogRank) and earlier than in patients with Fuchs' dystrophy (1.3%). CONCLUSIONS: In addition to well-established optical advantages, nonmechanical trephination seems to have no immunologic drawbacks.

Adolescent↗
PubMed1998

[Results of implantation of transsclerally sutured posterior chamber lenses in combination with penetrating keratoplasty].

UNLABELLED: Implantation of transsclerally sutured posterior chamber lenses is one possibility of surgical visual rehabilitation of eyes with pseudophacic or aphacic bullous keratopathy without zonular-capsular support. We analyzed the results and complications of the surgical procedures performed in our institution. PATIENTS AND METHODS: Out of 1567 penetrating keratoplasties and 220 transsclerally sutured posterior chamber lenses that were performed at our institution between 1991 and 1996, patients that underwent penetrating keratoplasty and sutured posterior chamber lens implantation in whom sufficient clinical information was available were selected and analyzed in a retrospective, nonselective study. Surgery was performed by a total of four surgeons and included anterior vitrectomy, inside-out suturing and synechiolysis if necessary. Detailed pre- and intraoperative data, postoperative course and complications were recorded and analyzed. RESULTS: A total of 96 eyes were analyzed (patient age 17-92 years, 49 male, 46 female). Penetrating keratoplasty was performed for pseudophacic (63) oder aphacic (15) bullous keratopathy or for corneal scars following penetrating injury (18). Mean follow-up was 22 months. In 82 of 96 eyes, visual acuity improved following surgery. Complications included rhegmatogenous retinal detachment in 4 eyes, graft rejection in 5 eyes, secondary angle-closure glaucoma caused by preexisting anterior synechiae in 7 eyes, and persisting cystoid macular edema in 19 eyes. Luxation or subluxation of the IOL and endophthalmitis were not observed in any of the patients. CONCLUSION: Implantation of transsclerally sutured posterior chamber lenses appears to be a safe procedure and is considered by us to be the procedure of choice to correct aphacia during penetrating keratoplasty in eyes with absent zonular-capsular support. The majority of postoperative complications is apparently caused by preexisting problems related to previous surgery and/or trauma, such as peripheral anterior synechiae, vitreous incarceration or cystoid macular edema.

Adolescent↗
PubMed1998

[Correlation between semi-quantitative classification of corneal topography and the coefficient of Fourier transformation after non-mechanical perforating keratoplasty].

BACKGROUND: Semiquantitative classification of corneal topography after penetrating keratoplasty has the potential for focusing information about the areal dioptric power of the cornea. The purpose of this study was to objectify the procedure of manual semiquantitative classification using a Fourier transform of corneal topography power data and to correlate both methods. PATIENTS AND METHODS: Fifty patients each (30 keratoconus, 20 Fuchs dystrophy) underwent nonmechanical trephination (excimer laser MEL60, Aesculap-Meditec, Jena) in penetrating keratoplasty. All procedures (7.5-mm trephination diameter in Fuchs, 8.0 mm in keratoconus, double-running 10-0 nylon suture) were done by one surgeon. Pre-, intra- and postoperative treatment were identical. At the follow-up examinations, the keratometric astigmatism, qualitative and quantitative criteria of the automatic videokeratography, visual acuity and refraction were assessed. Corneal topography was classified both manually and based on Fourier coefficients. RESULTS: After a mean follow-up of 24 +/- 5 months, keratometric net astigmatism was 3.0 and 2.7 D with keratoconus and Fuchs dystrophy. Corneal topography analysis showed a higher orthogonality of the bow-tie shape and less asymmetry between opposite hemimeridians with increasing follow-up after keratoplasty. The semiquantitative classification showed a statistically significant correlation with the classification based on Fourier coefficients, especially with higher astigmatism and after suture removal (P = 0.04/0.01 before/after suture removal). DISCUSSION: After nonmechanical trephination, the semiquantitative classification of corneal topography can be synthetized using Fourier analysis of corneal dioptric power data. In the future, this method may be favored for prediction of potential best-corrected visual acuity after penetrating keratoplasty.

Adult↗
PubMed1998

Juvenile open angle glaucoma: fine mapping of the TIGR gene to 1q24.3-q25.2 and mutation analysis.

Autosomal dominant juvenile open angle glaucoma (JOAG) is an early-onset form of primary open angle glaucoma (POAG), which has been linked to chromosome 1q21-q31. Recently, mutations in the trabecular meshwork inducible glucocorticoid response gene (TIGR), one of the candidate genes mapped in this region, were identified in glaucoma patients of several families. We screened for mutations of the TIGR gene in two German families with JOAG and in 100 unselected sporadic cases of POAG. In the first family we identified a Pro370Leu mutation and in the second family a Gly367Arg mutation cosegregating with the glaucoma phenotype. No pathogenic mutation was found in 100 sporadic cases but a Tyr347Tyr polymorphism was found in two patients. Furthermore, fluorescence in situ hybridization (FISH) analysis was used to map a TIGR-specific yeast artificial chromosome to 1q24.3-q25.2.

Adolescent↗
PubMed1998

Quantification of aqueous melanin granules in primary pigment dispersion syndrome.

PURPOSE: Aqueous melanin granules are essential in the pathogenesis of pigment dispersion syndrome and pigmentary glaucoma. We quantified aqueous melanin granules with the laser flare-cell meter in patients with pigment dispersion syndrome, assessed the measurement reproducibility, and correlated the numbers with clinical findings. METHODS: Aqueous melanin granules were counted by means of the cell count mode of the laser flare-cell meter (KOWA FC-1000; Kowa, Tokyo, Japan) in 42 eyes of 21 patients with primary pigment dispersion syndrome under three conditions (undilated pupils, dilated pupils, after exercise). The reproducibility of the measurements was determined with the intraclass correlation coefficient. A control group of 40 age- and sex-matched eyes was also examined after pupillary dilation. The results were correlated with biomicroscopic findings in eyes with pigment dispersion syndrome (retrocorneal Krukenberg spindle, iris transillumination, pigmentation of trabecular meshwork). RESULTS: Numerous aqueous melanin granules were detected in eyes with pigment dispersion syndrome (mean, 2.9 +/- 3.7 granules/0.075 mm3) but only small numbers were counted in normal eyes (0.2 +/- 0.3, P < .001). Medical pupil dilation caused an additional increase of aqueous melanin granules in pigment dispersion syndrome (6.3 +/- 5.3, P < .001), but not undilated exercise (climbing stairs) (2.9 +/- 3.7, P > .5). The reproducibility of the measurements was very high (intraclass coefficient >0.92). The number of melanin granules correlated with the degree of Krukenberg spindle (r = .61, P = .004) and with iris transillumination (r = .69, P = .001). CONCLUSIONS: Quantification of aqueous melanin granules yields reproducible results and shows increased numbers in pigment dispersion syndrome, especially after pupillary dilation. Aqueous melanin granule quantification may be useful for evaluating eyes with pigment dispersion syndrome and for assessing treatment effects.

Adult↗
PubMed1998

Infection of the corneal endothelium in herpes simplex keratitis.

PURPOSE: To describe viral infection of the corneal endothelium in a patient with recurrent herpes simplex virus keratitis in the corneal graft. METHODS: Case report. A healthy 28-year-old man presented with necrotizing stromal keratitis and corneal perforation in the corneal graft. A second penetrating keratoplasty was performed. The corneal button was processed for histopathologic, immunohistochemical, and electron microscopic studies. RESULTS: Histopathologically, the corneal endothelium showed viral inclusion bodies. Herpes simplex virus antigens and viral particles were identified in stromal keratocytes and corneal endothelial cells. CONCLUSION: Productive herpes simplex virus infection of the corneal endothelial cells may contribute to corneal graft failure in recurrent herpes simplex virus infections.

Adult↗
PubMed1998

Epithelioid cell Spitz nevus of the eyelid.

PURPOSE: To report a 20-month-old child with a rapidly growing dome-shaped red nodule on the left lower eyelid. The lesion was diagnosed clinically as an hemangioma, but microscopy disclosed an epithelioid Spitz nevus. METHOD: Case report. RESULT: Histopathologic examination of the excised lesion disclosed a Spitz nevus (benign juvenile melanoma) of a chiefly epithelioid cell type. CONCLUSIONS: The differential diagnosis of eyelid skin nodules in children should include Spitz nevus. This uncommon nevus has many cytologic features in common with nodular malignant melanoma. Histologically, it may be difficult to distinguish between nodular malignant melanoma and Spitz nevus.

Diagnosis, Differential↗
PubMed1998

Microcirculation architecture of metastases from primary ciliary body and choroidal melanomas.

PURPOSE: To describe the microcirculation architecture of metastatic choroidal and ciliary body melanoma. METHOD: Histologic sections of 35 metastases from 19 primary melanomas were stained to demonstrate microcirculation. RESULT: The appearance of microcirculatory networks in metastases is independent of the target organ but associated with the size of the metastatic deposit (estimated coefficient = 0.5959; SE = 0.3024; P = .0488). CONCLUSION: The microcirculatory patterns of primary uveal melanomas that are associated with metastatic behavior appear in foci of metastasis, regardless of the site of dissemination.

Choroid Neoplasms↗
PubMed1998

Blood-aqueous barrier after mechanical or nonmechanical excimer laser trephination in penetrating keratoplasty.

PURPOSE: To analyze whether nonmechanical trephination with an excimer laser influences post-operative blood-aqueous barrier breakdown after penetrating keratoplasty. METHODS: Patients undergoing penetrating keratoplasty for keratoconus or Fuchs dystrophy were prospectively randomly assigned to trephination by either excimer laser or conventional mechanical handheld motorized trephine. All surgery was performed by one surgeon, and preoperative, intraoperative, and postoperative treatment was identical in both groups. Aqueous flare was quantitatively determined postoperatively in a masked fashion by laser flare-cell meter. For statistical analysis, the nonparametric Wilcoxon-Mann-Whitney test was used. RESULTS: A total of 52 eyes of 52 patients were examined (Fuchs dystrophy, 10; keratoconus, 42). During the early postoperative period (days 3 to 9), eyes that had undergone nonmechanical excimer laser trephination (25/52) showed significantly (P < .005) lower flare values than did eyes that had undergone mechanical trephination (27/ 52). In both groups, flare values returned to normal levels by 6 weeks postoperatively. CONCLUSION: Early postoperative blood-aqueous barrier breakdown is less pronounced after penetrating keratoplasty with nonmechanical excimer laser trephination.

Adolescent↗
PubMed1998

Bilateral zonular cataract associated with the mitochondrial cytopathy of Pearson syndrome.

PURPOSE: To report a child with the mitochondrial cytopathy of Pearson syndrome and zonular cataract. METHOD: Case report. We describe a 6-year-old boy with Pearson syndrome. RESULTS: At age 3 years, the boy developed secondary strabismus caused by bilateral zonular cataract. Subsequently, he underwent successful bilateral cataract extraction with intraocular lens implantation. Postoperative visual acuity with best correction was RE, 20/25 and LE, 20/40. CONCLUSIONS: Children with Pearson syndrome should be examined ophthalmologically to rule out zonular cataract and possible amblyopia. Mitochondrial cytopathies such as Pearson syndrome should be included in the differential diagnosis of congenital and early juvenile cataract.

Anemia, Sideroblastic↗