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G O Naumann

Publications and source records attributed to G O Naumann.

At least 19 recordsLinked to original sources
PubMed2005

[Functional significance of adenosine receptors in the eye and their dysregulation in pseudoexfoliation syndrome].

BACKGROUND: Adenosine regulates many physiologic processes, such as aqueous humor secretion and intraocular pressure, via activation of its receptors. We investigated the expression of the receptor isoforms in eyes with PEX syndrome, which is associated with anterior chamber hypoxia and elevated intraocular pressure. MATERIALS AND METHODS: The mRNA and protein expression of the adenosine receptor subtypes in anterior segment tissues of patients with PEX syndrome, glaucomas, and normal control eyes were analyzed comparatively. RESULTS: Whereas the receptor subtypes A1, A2a, and A2b displayed no differential expression between PEX and control tissues, expression of the A3 adenosine receptor was consistently enhanced in the nonpigmented ciliary epithelium of all PEX eyes, independent of the presence of glaucoma, compared to normal and glaucomatous control eyes. CONCLUSION: Considering the known role of the A3 adenosine receptor in modulating aqueous humor secretion, its selective upregulation in the ciliary epithelium may confer cytoprotection and be accessible to therapeutic intervention in PEX patients.

Aged↗
PubMed2004

[Solid limbal dermoid in an 80-year-old patient].

BACKGROUND: Typically solid limbal dermoids are excised in pre-school age unless a high irregular astigmatism and its risk for amblyopia lead to an earlier intervention. CASE REPORT: An 80-year-old lady from a rural area complained about a burning, tearing and foreign body sensation of the left eye for two months. In the past two years she had recognized that an extraocular prominence which had been present since birth had shown a tendency to grow. Slit lamp examination showed a markedly prominent and vascularized limbal tumor from 3.30 to 7.00 o'clock. Paralleling the border of the mass there was a bow-shaped stromal lipoid deposit reaching from limbus to limbus. Gonioscopic examination revealed a deep penetration of the process almost into the anterior chamber. The tumor was excised and some fatty tissue adjacent to Descemet's membrane was left. Histological assessment brought us to the diagnosis of a chronically irritated, predescemetal limbal dermoid with marked secondary vascularization, epidermalization, elastoid degeneration and degenerative arcus lipoides. CONCLUSIONS: The excision of the limbal dermoid in the described case was performed in the later stage of life. When indicated cosmetically or medically, surgery should typically take place in pre-school age and be performed as a lamellar excision.

Aged↗
PubMed2001

Pseudoexfoliation syndrome and aneurysms of the abdominal aorta.

We assessed the association between pseudoexfoliation syndrome, a common age-related fibrillopathy of unknown cause, and vascular diseases, especially aneurysms of the abdominal aorta. In a prospective single-blind study we ophthalmoscopically examined 55 patients with aneurysms of the abdominal aorta and 41 controls with carotic-artery occlusion. 24 of 55 patients with aortic aneurysm showed signs of manifest (17 of 55 patients) or early-stage (seven of 55) pseudoexfoliation syndrome. Eight of 41 control patients showed manifest (seven of 41 patients) and early (one of 41) ocular pseudoexfoliation (p=0.016). These findings, including histopathological examinations, suggest an association between aneurysms of the abdominal aorta and pseudoexfoliation syndrome.

Aged↗
PubMed2001

"Masked" pseudoexfoliation syndrome in unoperated eyes with circular posterior synechiae: clinical-electron microscopic correlation.

OBJECTIVE: To investigate the prevalence of "masked" pseudoexfoliation (PEX) syndrome in eyes with circular posterior synechiae receiving antiglaucomatous therapy with miotics. DESIGN: Cross-sectional prospective study. METHODS: Twenty-eight eyes of 27 consecutive patients with circular posterior synechiae and a history of miotic drug use without previous intraocular surgery, inflammation, or trauma, and without conventional signs of PEX material in the anterior chamber were included in the study. All eyes were investigated by slitlamp biomicroscopy and gonioscopy of the anterior chamber before extracapsular cataract surgery for the presence of typical PEX-associated iris pigment epithelial changes, such as peripupillary atrophy and trabecular meshwork melanin granule deposition. The anterior chamber depth, lens thickness, and axial lengths of the eyes were measured by A-scan immersion sonography. The excised anterior lens capsules obtained during extracapsular cataract surgery were investigated for the presence of precapsular fibrillar PEX deposits by electron microscopy. MAIN OUTCOME MEASURE: The prevalence of masked PEX syndrome in eyes with circular posterior synechiae receiving antiglaucomatous therapy with miotics. RESULTS: Transmission electron microscopy of unselected nonserial sections revealed a precapsular layer consisting of typical PEX fibers or microfibrils, which indicated early stages of PEX syndrome in 18 (64%) of 28 eyes with circular posterior synechiae. Melanin granules were frequently found adhering to the fibrillar layer. Eyes with precapsular fibrillar deposits showed significantly greater trabecular meshwork pigmentation than eyes without such deposits. Differences in age, lens thickness, axial length of the eye, anterior chamber depth, and degree of peripupillary atrophy were, however, not statistically significant between the groups with and without electron microscopic evidence of PEX deposits. CONCLUSIONS: Circular posterior synechiae were more frequently associated with manifest or early stages of PEX syndrome. However, the formation of broad posterior synechiae in miosis prevented a definite clinical diagnosis based on the classic changes of the anterior lens capsule. In eyes with spontaneous or miotic-induced circular posterior synechiae without other obvious cause, the masked variant of PEX syndrome should always be considered.

Aged↗
PubMed2001

Unilateral or asymmetric pseudoexfoliation syndrome? An ultrastructural study.

BACKGROUND: Clinically, most patients with pseudoexfoliation (PEX) syndrome reveal only unilateral ocular involvement. However, the generalized nature of the disorder suggests that PEX syndrome is clinically asymmetric rather than strictly unilateral. OBJECTIVE: To perform an ultrastructural study of the contralateral eyes in patients with unilateral PEX syndrome. METHODS: Five pairs of donor eyes with slitlamp microscopic, macroscopic, and light microscopic evidence of unilateral PEX syndrome and 6 normal control eyes were investigated by transmission electron microscopy and light and electron microscopic immunohistochemistry using antibodies against the human natural killer (HNK-1) epitope and against latent transforming growth factor beta1-binding protein, both markers for the identification of PEX deposits. RESULTS: Ultrastructural alterations were observed in anterior segment tissues of all apparently not involved fellow eyes. These included (1) deposits of typical PEX fibrils on the iris and ciliary epithelia and in the dilator muscle of the iris; (2) increased accumulation of extracellular matrix, including microfibrils and reduplicated basement membrane material in the periphery of iris vessels, in the dilator muscle and in the juxtacanalicular tissue of the trabecular meshwork; and (3) degenerative changes of the iris pigment epithelium and dilator muscle cells. Latent transforming growth factor beta1-binding protein- and HNK-1-positive deposits indicating PEX material accumulations were detected in the periphery of iris vessels and in the dilator muscle in all affected and contralateral eyes, but not in the control eyes. CONCLUSIONS: These subclinical alterations of contralateral eyes in clinically so-called unilateral PEX syndrome support the concept that PEX syndrome is a generalized basically bilateral disorder with a clinically marked asymmetric manifestation. The iris changes may account for the clinical signs characteristic of early stages, such as melanin dispersion, peripupillary atrophy, trabecular meshwork pigmentation, and insufficient asymmetric mydriasis. The findings should be considered in the clinical management of the patients. CLINICAL RELEVANCE: In view of the fact that PEX syndrome is the most common identifiable cause of open-angle glaucoma worldwide and as it is an important risk factor for a wide spectrum of ocular complications, particularly during cataract surgery, the potential involvement of both eyes in the PEX process is of clinical significance.

Aged↗
PubMed2001

Immunohistochemical classification of primary and recurrent macular corneal dystrophy in Germany: subclassification of immunophenotype I A using a novel keratan sulfate antibody.

Macular corneal dystrophy (MCD) is an autosomal recessive disease characterized by abnormal deposition of glycosaminoglycans in corneal stroma, keratocytes, Descemet's membrane and corneal endothelium. According to the presence and distribution of sulfated keratan sulfate (KS)-epitopes in serum and cornea (using mAb 5-D-4), MCD can be classified into three immunophenotypes: type I, I A and II. The purpose of this study is to evaluate the immunophenotype of primary and recurrent MCD and to analyze the reactions of a novel KS-antibody in MCD corneas, which recognizes an epitope localized in the binding region of KS-chains to the core protein (mAb 3D12/H7). Indirect immunohistochemistry for KS (mAbs 3D12/H7 and 5-D-4) was performed on 44 corneas of 37 patients with MCD including two recurrences. Immunogold labeling was used to localize KS ultrastructurally within keratocytes. The serum concentration of KS (cKS) was determined in a serum antigen-inhibition assay. Immunohistochemically, no reaction was observed using mAb 5-D-4 in 18 corneas of 16 patients (43% of 37 patients; immunophenotype I). Positive reactions within single keratocytes but not in the stroma, were seen in 22 corneas of 17 patients (46% of 37 patients; immunophenotype I A) and positive reactions in keratocytes and extracellular stroma were found in four corneas of four patients (11% of 37 patients: immunophenotype II). For analysis of cKS a total of seven samples was available. Whereas in the samples of the five patients with immunophenotypes I and I A cKS was below the limit of detection, in the two sera from patients with immunophenotype II, cKS was normal (cKS = 1243 and 1380 nmol l(-1)). The two recurrences demonstrated immunophenotype II. Using mAb 3D12/H7, MCD immunophenotype I A can be further subclassified in type I A 1 (lacking reaction with mAb 3D12/H7 in keratocytes; 77%) and type I A 2 (positive reaction with mAb 3D12/H7 within keratocytes; 23%). MCD immunophenotype I A can not only be found in Saudi Arabia, but is as common as immunophenotype I in German patients. The only recurrences of MCD necessitating regrafting occurred in two patients with immunophenotype II possibly suggesting a higher risk for recurrence in this immunophenotype. The mAb 3D12/H7 allows a further subclassification of immunophenotype I A into type I A1 and 2. This points to a broader spectrum of MCD immunophenotypes and indirectly to a broader corneal proteoglycan pathology in MCD.

Antibodies, Monoclonal↗
PubMed2001

Role of transforming growth factor-beta1 and its latent form binding protein in pseudoexfoliation syndrome.

Pseudoexfoliation (PEX) syndrome is a common and clinically important systemic condition characterized by the pathologic production and accumulation of an abnormal fibrillar extracellular material in many intra- and extraocular tissues. Recent evidence suggests that it is a type of elastosis associated with the excess synthesis of elastic microfibrillar components such as fibrillin-1. Since transforming growth factor (TGF)-beta is a major modulator of extracellular matrix formation, the potential involvement of TGF-beta and its latent form binding protein (LTBP) in this aberrant matrix process was investigated. The expression of various isoforms of TGF-beta and LTBP was investigated in the anterior segment tissues of PEX and control eyes on the protein and mRNA level by light and electron microscopic immunohistochemistry, in situ hybridization, and semiquantitative RT-PCR. TGF-beta1 and TGF-beta2 levels were measured in aqueous humor and serum of PEX and control patients by ELISA. Cultures of Tenon's capsule fibroblasts were established to study the effect of TGF-beta1 on fibrillin-1 mRNA expression by Northern blot analysis. Significantly increased concentrations of both total and active TGF-beta1 were measured in the aqueous humor of PEX eyes without and with glaucoma as compared to control eyes, whereas levels of TGF-beta2 were not significantly different. The expression of TGF-beta1, LTBP-1, and LTBP-2, but not TGF-beta2, was markedly increased in anterior segment tissues of PEX eyes, particularly in the non-pigmented epithelium of the ciliary body, on both the mRNA and the protein level. Latent TGF-beta1 staining was consistently associated with PEX material deposits and could be released by proteolytic processing. Double immunolabeling revealed clear co-localization of LTBP-1 and -2 with latent TGF-beta1 and with fibrillin-1 on PEX fibrils. The expression of mRNA coding for fibrillin-1 was up-regulated in vitro by TGF-beta1. This study provides evidence for a significant role of TGF-beta1 and the LTBPs 1 and 2 in PEX syndrome. The results suggest that increased levels of latent and active TGF-beta1 in the aqueous humor of PEX patients, derived from enhanced local synthesis and activation, promote the buildup of the abnormal extracellular elastic material characteristic of PEX syndrome. They further support a dual role for LTBPs, both as integral structural components of PEX fibers and as a means of matrix anchorage of latent TGF-beta1, representing one possible mechanism for the regulation of TGF-beta1 activity in PEX eyes. Future therapeutic strategies might focus on TGF-beta1 antagonistic approaches.

Aged↗
PubMed2001

[Morphological results after eccentric perforating keratoplasty].

OBJECTIVE: Due to unfavourable optical and immunological conditions, an eccentric position of the corneal transplant is limited to curative or tectonic indications. The purpose of this study was to assess the morphological results of eccentric homologous penetrating keratoplasty (PK) with respect to diagnosis as well as position and size of the corneal graft. PATIENTS AND METHODS: In our retrospective study, 122 cases of eccentric homologous PK in 96 eyes between 01/1989 and 10/1997 were included, which in 104 patients was necessary because of a corneal ulcer (36 previous PK, 21 areactive/rheumatic, 20 herpetic, 15 bacterial, 12 other). Elective PK was performed on 6 eyes with corneal scars, 7 eyes with ectatic corneal diseases (ECT) and 5 others. Using postoperative slides the following parameters were quantified: the graft diameter (GD) and transparency, the distance of the geometric centre of the cornea from the central trephination margin (ABS) as well as from the geometric centre of the graft (decentration, DEZ). Of these, 17 grafts were classified as eccentric peripheral keratoplasty (EPK) with the optical axis through the host cornea and 67 as eccentric central keratoplasty (ECK) with the optical axis through the graft. RESULTS: The average follow-up period was 25 months. In EPK (ulcers only, 5.0 +/- 1.7 mm) the mean GD was significantly lower than in ECK (78% ulcers, 7.0 +/- 1.3 mm) (p < 0.001). The decentration of EPK (3.5 +/- 1.1 mm) was significantly higher than for ECK (1.4 +/- 0.8 mm, p < 0.001). ABS of EPK was +1.3 +/- 0.9 mm and for ECK was -2.0 +/- 1.0 mm. Of the grafts in EPK and ECK 46%/57%, respectively were crystal clear, 18%/15% respectively showed minor decompensation and 36%/28% were completely cloudy. In cases of ulcers/scars/ECT/others, 45%/75%/100%/75% were crystal clear, respectively, 18%/25%/0%/0% showed minor decompensation and 37%/0%/0%/25% were completely cloudy. With increasing stages of cloudiness, the mean graft decentration increased from 1.4 +/- 1.1 mm (crystal clear) to 1.7 +/- 1.2 mm (minor decompensation) and 2.2 +/- 1.4 mm (completely cloudy). Transplants with greater GD (p = 0.04) and ABS (p = 0.01) were significantly more often clear. Ulcers were significantly more cloudy than scars/ECT (p < 0.01). The position of the graft and its cloudiness was not significantly correlated. CONCLUSION: The diagnosis leading to eccentric PK seems to have the greatest impact on long-term graft transparency. Our results indicate that an increasing decentration of the graft is not inevitably associated with an increasing probability of clouding. A central penetrating repeat keratoplasty may be considered in the non-inflamed interval after eccentric tectonic mini-keratoplasty.

Adolescent↗
PubMed2001

[Quality management according to DIN EN ISO 9001 at a university eye hospital].

BACKGROUND: Quality assurance is an integral part of modern microsurgical ophthalmology. Health care laws also mandate overall quality management. MATERIALS AND METHODS: In recent years we have standardized the preexisting features of quality management according DIN EN ISO 9001 and have integrated previously missing features. RESULTS: Establishing quality management according to ISO 9001 is possible even at a university eye hospital and department of ophthalmology. Certification according to ISO 9001 specifications was granted in April 1999. The major difficulty was in translating industrial norms to the context of an eye hospital. It was also difficult to overcome skepticism towards quality-assurance measures that lie beyond ophthalmological quality control. CONCLUSION: It is useful and feasible to establish a quality management system at German university eye hospitals and departments of ophthalmology. Certification according to ISO 9001 is one possibility to make a quality management system transparent and evaluable both inside and outside the hospital.

Certification↗
PubMed2001

Graft endothelium and thickness after penetrating keratoplasty, comparing mechanical and excimer laser trephination: a prospective randomised study.

PURPOSE: To assess the impact of nonmechanical trephination on the graft endothelium and thickness after penetrating keratoplasty (PK). METHODS: Inclusion criteria for this prospective, randomised, cross-sectional, clinical study were: (1) Treatment between October 1992 and December 1997; (2) one surgeon (G.O.H.N.); (3) primary central PK; (4) Fuchs' dystrophy (diameter 7.5/7.6 mm) or keratoconus (diameter 8.0/8.1 mm); (5) graft oversize 0.1 mm; (6) no previous intraocular surgery; (7) 16-bite double-running diagonal suture. In 179 patients (mean age 51+/-18 years), PK was performed using either the 193-nm Meditec MEL60 excimer laser ("Excimer") along metal masks with eight "orientation teeth/notches" (53 keratoconus, 35 Fuchs' dystrophy) or motor trephination with the Mikrokeratron (Geuder) ("Control": 53 keratoconus, 38 Fuchs' dystrophy). For donor trephination from the epithelial side an artificial anterior chamber was used in both groups. In 27% of the excimer and 29% of the control group a triple procedure was performed. Specular microscopy (EM-1000, Tomey) and pachymetry (SP-2000, Tomey) were performed before removal of the first suture (0.4+/-0.2 years postoperatively), before (1.1+/-0.4 years) and after (1.7+/-0.6 years) removal of the second suture but before any additional surgical intervention. RESULTS: Endothelial cell count: Neither "two-sutures-in" (1953+/-426/1804+/-385 cells/mm2, p=0.13), "one-suture-in" (1629+/-439/1765+/-440 cells/mm2, p=0.27), nor "all-sutures-out" (1259+/-493/1294+/-532 cells/mm2, p=0.83) differed significantly between Excimer and Control. Graft thickness: Neither "two-sutures-in" (527+/-58/524+/-16 mucrom, p=0.89), "one-suture-in" (537+/-72/551+/-40 microm, p=0.86), nor "all-sutures-out" (576+/-53/565+/-62 microm, p=0.38) differed significantly between Excimer and Control. Cell count and corneal thickness were not significantly different comparing Fuchs' dystrophy and keratoconus or comparing PK only and triple procedures. Graft thickness and endothelial cell count correlated highly significantly inversely with "all sutures out" (P<0.0001). CONCLUSIONS: Excimer laser trephination from the epithelial side using an artificial anterior chamber in donors seems to have no disadvantages concerning the graft endothelium after PK. Endothelial cell loss was not increased in eyes with Fuchs' dystrophy compared with keratoconus or after triple procedures compared with PK only.

Adolescent↗
PubMed2001

Blood-aqueous barrier breakdown after penetrating keratoplasty with simultaneous extracapsular cataract extraction and posterior chamber lens implantation.

BACKGROUND: The purpose of this study was to quantify breakdown of the blood-aqueous barrier (BAB) following penetrating keratoplasty (PK) with simultaneous extracapsular cataract extraction and posterior chamber lens implantation (triple procedure) and compare it with the alterations following PK only. METHODS: This study included 72 eyes after triple procedure and 227 eyes after PK only. The diagnosis for PK was Fuchs dystrophy in 39%, keratokonus in 44%, stromal corneal dystrophy in 3% and avascular corneal scars in 6% of cases. The postoperative topical steroid treatment was standardized in both groups. Aqueous flare was quantified using the laser flare-cell meter (FC-1000, Kowa) at defined postoperative intervals (10 days, 6 weeks, then every 3 months until 1 year postoperatively). Patients with conditions associated with impairment of the BAB were excluded from the study. RESULTS: In the early postoperative course, aqueous flare values (photon counts/ms) were significantly higher in patients with triple procedure (21.9 +/- 11.0) than in patients with PK only (9.8 +/- 3.2; P = 0.001). At 6 weeks postoperatively, aqueous flare returned to normal levels in patients after PK only (5.2 +/- 2.3), whereas patients with triple procedure still showed significantly increased flare values (10.8 +/- 5.6; P = 0.01). At 6 months postoperatively, aqueous flare values of patients with triple had returned to normal levels (6.8 +/- 3.8) and did not differ significantly from those after PK only (5.2 +/- 1.9; P = 0.09). CONCLUSION: Our results indicate that triple procedure causes a more extensive and longer-lasting breakdown of the blood-aqueous barrier than PK only. Quantification of aqueous flare with the laser flare-cell meter is useful in the postoperative follow-up after triple procedure. Further studies are required to investigate the clinical relevance of BAB breakdown on endothelial cell count and the incidence of subsequent immunological graft rejection.

Aqueous Humor↗
PubMed2001

Persisting retinal ganglion cell axons in blind atrophic human eyes.

PURPOSE: To evaluate enucleated blind atrophic human eyes for the persistence of retinal ganglion cell axons. This might be of relevance for contact to an electronic prosthesis in the future. METHODS: A total of 2460 surgically enucleated eyes were studied in our ophthalmic pathology laboratory between 1981 and 1996. All eyes histopathologically classified as displaying ocular atrophy with shrinkage (axial length < or = 21 mm) and with an available optic nerve cross section without crush artifacts were selected. Only eyes of patients older than 18 years and without light perception prior to enucleation were analyzed (n = 57). Optic nerve fibers were counted under light microscopy in semithin optic nerve sections. RESULTS: Axons amounting to more than 5% of the mean axon count in normal eyes (> 57,950 axons) were detected in 24 (42%) of 57 optic nerves, and an axon count more than 10% of the mean normal count (> 115,900 axons) was found in 15 (26%) of 57 optic nerves. The retina was at least partially detached and disoriented in all 57 eyes. The inner nuclear layer was detectable in 46 (81%) of eyes, whereas the outer nuclear layer was present in 13 (23%) of 57 eyes; photoreceptors were detectable by light microscopy in only 3 eyes (5%). Intraocular calcification due to osseous metaplasia of the retinal pigment epithelium was present in 62% of the globes. CONCLUSION: Blind atrophic human eyes reveal persisting retinal ganglion cell axons. Whether direct electrical stimulation of these axons or their retinal ganglion cells has the potential to create visual information remains to be studied.

Adolescent↗
PubMed2001

Effect of neodymium:YAG laser iridotomy on number of aqueous melanin granules in primary pigment dispersion syndrome.

PURPOSE: Increased numbers of aqueous melanin granules have been reproducibly demonstrated in eyes with pigment dispersion syndrome using the cell count mode of the laser flare-cell meter. It was the aim of this study to measure the exact number of aqueous melanin granules in eyes with pigment dispersion syndrome and pigmentary glaucoma before and after Nd:YAG laser iridotomy. METHODS: Nine eyes of seven patients with a clinical diagnosis of primary pigment dispersion syndrome and secondary open-angle glaucoma (mean age 41.1 +/- 10.8 years) were included in this study. Aqueous cells were quantified using the cell count mode of the laser flare-cell meter (Kowa FC-1000) before and 30 min after medical pupillary dilation. Measurements were performed before and 15 +/- 7 weeks after Nd:YAG laser iridotomy. The main outcome measure was the number of aqueous melanin granules before and after Nd:YAG laser iridotomy. RESULTS: The number (mean and quartiles) of aqueous melanin granules/0.075 microl aqueous humor (normal/dilated pupil) before antiglaucoma treatment was 4.5 (4.0, 7.25)/ 9.0 (5.0, 13.0) and was significantly reduced after iridotomy [1.5 (0.75, 3.25)/4.0 (1.6, 6.25), P=0.016]. CONCLUSION: Nd:YAG laser iridotomy results in significant (65%) decrease of aqueous melanin granules in eyes with primary pigment dispersion syndrome. This finding appears to confirm the concept of reverse pupillary block in primary pigment dispersion syndrome and may indicate that laser iridotomy is a useful treatment option in this condition.

Adult↗
PubMed2001

Impact of short-term versus long-term topical steroids on corneal neovascularization after non-high-risk keratoplasty.

PURPOSE: To analyze incidence and extent of corneal neovascularization (CN) after non-high-risk keratoplasty and to find out whether duration of postoperative topical steroid therapy (6 vs 12 months) affects CN, corneal endothelial cell count, pachymetry, aqueous flare values, and best-corrected visual acuity at 1 year after keratoplasty. METHODS: Patients of the prospective Erlangen non-high-risk keratoplasty study with available high-quality corneal photographs taken preoperatively and 1 year later were analyzed (n=136). Corneal photographs were evaluated by two independent observers in a standardized semiquantitative fashion. Slides were projected with 100x magnification and corneal vessels classified into five grades with regard to the limbus, sutures and host-graft junction in each of 12 corneal sectors. Incidence and extent of CN after keratoplasty and relation to short-term (0-6 months) versus long-term (0-12 months) postoperative topical steroid therapy were analyzed. The effect of duration of topical steroid therapy on corneal endothelial cell count, pachymetry, aqueous flare values, and best corrected visual acuity was also analyzed. Of the 136 patients, 69 (51%) were randomly assigned to short-term and 67 to long-term topical prednisolone acetate 1%. RESULTS: Fifty-eight percent of patients (n=79) developed a CN within 1 year after keratoplasty in at least one corneal sector (mean 3.1 +/- 2.2, range 1-10). At 1 year after keratoplasty, only in 12% of these patients did at least one vessel reach the host-graft junction or grow into the donor cornea, whereas in 51% vessels were seen beyond the outer suture ends of the double running suture without reaching the host-graft junction. In 37%, capillaries were located between limbus and outer suture ends. New vessels usually pointed directly or indirectly to the outer suture ends and usually were located around the 12 o'clock and 6 o'clock positions. There was no significant difference regarding incidence and extent of CN 1 year after keratoplasty between the long-term and the short-term group. Duration of topical steroid therapy had no significant effect on corneal endothelial cell count and thickness, aqueous flare values and best-corrected visual acuity at 6 and 12 months postoperatively (only at 12 months, corneas in the long-term treatment group were slightly thicker; P=0.03). Interobserver correlation of vessel assessment was 0.77 (Kendall's tau B). CONCLUSIONS: CN is a common phenomenon after non-high-risk keratoplasty. New vessels rarely reach the host-graft junction, most commonly develop from the 6 o'clock and 12 o'clock positions and are usually located between epithelium and Bowman's layer (i.e., at the level of the superficial suture). The direction of vessel growth from the limbus towards the outer suture ends suggests release of angiogenic factors in this area. Prolongation of topical steroid therapy after non-high-risk keratoplasty beyond 6 months in this study did not significantly influence incidence and extent of CN, corneal endothelial cell count, aqueous flare values and best-corrected visual acuity observed 1 year after keratoplasty.

Administration, Topical↗
PubMed2001

Silicone oil-associated optic nerve degeneration.

PURPOSE: To report the frequency and extent of silicone oil migration into the optic nerve during silicone oil endotamponade. METHODS: Histopathologic analysis of 74 eyes enucleated after silicone oil endotamponade. RESULTS: In 14 of 74 enucleated eyes (24%), optically empty vacuoles regarded as silicone oil vacuoles were observed in the retrolaminar optic nerve. In three eyes, silicone oil in the optic nerve was surrounded by a granulomatous inflammatory reaction. In serial cross sections, the vacuoles extended up to the line of surgical transsection (up to 9 mm) of the optic nerve and constituted up to 40% of the total cross-sectional area. CONCLUSIONS: After silicone oil endotamponade, silicone oil may replace a considerable amount of tissue of the retrolaminar optic nerve. A granulomatous inflammatory reaction surrounding silicone oil may add to optic nerve damage.

Eye Enucleation↗