Jens Martin Rohrbach

Complete occlusion of the anterior capsular opening after intact capsulorhexis: clinicopathologic correlation

PURPOSE To report histopathologic findings of capsule contraction syndrome with complete occlusion of the capsulorhexis opening. METHODS Case report. In an 81-year-old woman, a complete occlusion of the anterior capsulorhexis opening developed 2 months after phacoemulsification and intraocular lens implantation. We surgically removed the contracted anterior capsule and analyzed the membrane by standard light microscopy and actin immunohistology. RESULTS Light microscopic analysis of the membrane showed fibrous tissue subcapsularly with metaplastic lens epithelial cells. The contracted capsulorhexis opening was filled completely with proliferated actin-positive lens epithelial cells. CONCLUSIONS Complete occlusion of the capsulorhexis opening can be attributed to excessive shrinkage of the capsule, probably caused by actin filaments found in the residual lens epithelial cells together with weak zonular support, and to the occlusion of the remaining central defect by massive proliferation of metaplastic lens epithelial cells.

Simultaneous Bilateral Diffuse Melanocytic Uveal Hyperplasia

A 52-year-old woman noted loss of vision in August 1984. Clinical examination disclosed iris cysts and ciliary body cysts, macular edema, and uveal nevi. Cataract extraction and pressure-lowering operations were required in both eyes because of a tumor-induced angle-closure glaucoma. Vision, however, progressively decreased to light perception in each eye. Both eyes were finally enucleated because a malignant melanoma could not be ruled out, though iris tissue obtained in 1985 suggested a nevuslike process. Histologic study indicated a bilateral uveal hyperplasia. Results of light and electron microscopy, immunologic studies, and suspension cell culture suggested that the uveal hyperplasia was more likely a melanoma of low malignancy than a nevuslike process. We could not detect an extraocular primary tumor and assumed that this condition constituted an oncogenic syndrome.

Sutureless amniotic membrane fixation using fibrin glue for ocular surface reconstruction in a rabbit model.

Purpose: Amniotic membrane transplantation has become an important treatment option for corneal surface reconstruction. However, suture fixation of the transplant has various disadvantages like corneal irritation, scarring, graft loss due to membrane shrinkage, and the need for subsequent suture removal. Replacement of sutures by bioadhesives might be an advantageous alternative. This controlled study was designed to evaluate a new sutureless technique for amniotic membrane fixation onto the corneal surface by using fibrin glue. Methods: Standardized disks of cryopreserved amniotic membranes were transplanted onto the deepithelialized cornea of 12 rabbits using either conventional suture fixation or a new fibrin glue technique. The rabbits were followed-up with slit-lamp examination and fluorescein staining until epithelialization was completed. Consecutively, the rabbits were killed and the eyes processed for histology and immunohistochemistry for cytokeratin-3. Results: All membranes of both groups stayed in place throughout the follow-up time and showed a progressive graft epithelialization that was completed after 12 days. Whereas suture-fixated membranes showed progressive tissue shrinkage, fibrin-glued sheets remained unaltered. In the bioadhesive group, histology revealed a smooth fibrin layer in the graft-host interface and a continuous, stratified layer of cytokeratin-3 expressing corneal epithelial cells on the membrane surface. In contrast, suture-fixated membranes showed contracted and prominent membrane edges with epithelial ingrowth into the submembrane interface. Conclusion: Our results demonstrate the general feasibility of reproducible and reliable sutureless amniotic membrane fixation onto the corneal surface in rabbits. Stable adherence is maintained until epithelialization is completed. The sutureless technique gives sufficient manipulation time for the sheet before the final cross-linking process is completed. Furthermore, several advantageous characteristics could be demonstrated as increased biocompatibility, better epithelialization pattern and the lack of membrane shrinkage.

Paraproteinemic Corneal Deposits in Plasma Cell Myeloma

We treated two patients who had IgG-kappa-light chain monoclonal gammopathy with partially crystalline and partially amorphic corneal deposits. Impairment of vision made keratoplasty necessary for each patient. Histologic examination of the corneal specimens showed deposits that stained positively for Massons trichrome in all corneal cells. Immunohistochemical tests identified these deposits as IgG-kappa-light chain immunoglobulin fragments. Electron microscopy showed intracellular, rhomboid-shaped deposits enveloped by a membrane. The same deposits appeared in the conjunctival epithelium, within subconjunctival fibrocytes, and in the plasma cells of the bone marrow. Immunoelectrophoresis showed IgG-kappa-light chain fragments in the blood serum, the lacrimal film, and the aqueous humor. This suggests that the intracellular immunoglobulin fragments may have entered the corneal and conjunctival epithelium by way of the lacrimal film, the keratocytes by way of the corneo-scleral limbus vasculature, and the endothelial cells from the aqueous humor.

Intraocular lens calcification after keratoplasty.

Purpose: To report calcification of intraocular lenses (IOLs) after various keratoplasty procedures. Methods: Clinical data of all cases with calcified IOLs after keratoplasty procedures were analyzed. A total of 6 explanted IOLs were analyzed with light microscopy before and after staining with 1% alizarin red and the von Kossa method. Results: A total of 7 cases occurred after Descemet stripping automated endothelial keratoplasty, 1 case after deep anterior lamellar keratoplasty, and 2 cases after penetrating keratoplasty. Median time interval from keratoplasty to first notice of IOL opacification was 6.5 months (minimum 3 months, maximum 51 months). A total of 3 IOLs had been placed at the time of keratoplasty and 7 IOLs before keratoplasty. All affected IOLs were hydrophilic acrylic and comprised IOLs from at least 3 different polymer sources. Common clinical aspects were some amount of inflammation in the anterior chamber during the postoperative period and use of air at the end of surgery in 8 of the 10 cases. Histochemical analysis demonstrated the presence of fine granular deposits located within the very superficial optic material in all cases. The deposits stained positive for calcium with alizarin red and the von Kossa method. Conclusions: IOL calcification associated with keratoplasty in our series does not seem to be a problem related to a specific IOL model or polymer. The process of calcification may be mediated by inflammation, which also may be related to multiple injections of air into the anterior chamber.

Primary silicone oil tamponade in the management of severe intraocular foreign body injuries: an 8-year follow-up.

Purpose: To evaluate the long-term outcome of pars plana vitrectomy and primary silicone oil tamponade in patients with severe intraocular foreign body (IOFB) injuries and high risk of proliferative vitreoretinopathy (PVR). Methods: This retrospective consecutive study included 23 patients with severe IOFB injuries who had extensive lacerations including sclera, choroid, and retina, and were complicated by predictive factors for elevated proliferative activity and an unfavorable outcome. All patients underwent pars plana vitrectomy, removal of the IOFB, and primary silicone oil tamponade and were followed up for a mean 8.9 years. Main functional outcome was assessed as final best-corrected visual acuity. Anatomic success was defined as permanent retinal attachment. Results: PVR occurred in 70% of all eyes and required 16 revisions. Silicone oil was removed in 78% of the eyes after a mean tamponade duration of 9.1 months. Complete retinal attachment was achieved in 83% of the eyes. Three eyes developed a persisting hypotony that was stabilized under permanent silicone oil. Functional stabilization was observed in the third year resulting in a final visual acuity of 20/630. Useful vision of better than 20/400 could be preserved in 55% of the patients. Only one eye underwent a late enucleation after 6.8 years. Conclusions: Primary silicone oil stabilizes the retina during the critical period of active PVR and may limit the visual loss in selected high-risk eyes in the long term.

Muscarinic acetylcholine receptor subtypes in human corneal epithelium and endothelium.

BackgroundMuscarinic acetylcholine receptors are located throughout the body. The demonstration of muscarinic receptors in corneal tissue has been inconsistent. Using freshly fixed human corneal tissue, we show a complete profile of muscarinic receptor subtypes in human corneal epithelium and endothelium.MethodsMuscarinic receptor sites were studied using immunocytochemistry, immunofluorescence and immunoblotting.ResultsAntibodies to M2, M4 and M5 muscarinic receptor subtypes bound in human corneal epithelium and endothelium. No binding was found for antibodies to M1 and M3 muscarinic receptor subtypes.ConclusionsOur studies indicate the presence of M2, M4 and M5 muscarinic acetylcholine receptor subtypes in human corneal epithelium and endothelium. These receptors may play a role in the regulation of corneal homeostasis, other functions, like wound healing, or the pathogenesis of corneal diseases.

A case of cutaneous melanoma metastatic to the vitreous cavity: possible pathomechanism and review of the literature

BackgroundIsolated vitreous metastases are extremely rare and the pathogenesis of metastasis is still unclear. Here we present the detailed description of the disease progression in a 68-year-old patient with vitreous seeding of a metastatic cutaneous melanoma beginning at a very early stage.MethodsInterventional case report and review of the literature.ResultsThe initial retrohyaloidal metastatic lesion was identified adjacent to a small epiretinal hemorrhage. As the disease progressed golden brown spherules appeared in the posterior vitreous emanating from the area of the lesion. Further progression led to a dense metastatic infiltration of the entire vitreous cavity and a decline of the visual acuity to 20/1200. Diagnostic and therapeutic pars plana vitrectomy was performed to confirm the diagnosis and preserve the eye and useful vision.ConclusionsFor the first time the formation of vitreous metastases derived from cutaneous melanoma was carefully studied beginning at a very early stage. This made it possible to analyze the rare mechanism of vitreous metastasis, which has not been conclusively known till now. The features of metastatic cutaneous melanoma to the vitreous are discussed in context of a review of the literature that resulted from the study of 17 patients with 22 affected eyes.

Adrenergic Regulation of cAMP/Protein Kinase A Pathway in Corneal Epithelium and Endothelium

Purpose: The G-protein-coupled receptor/cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) pathway is one of the most common and versatile signal pathways in eukaryotic cells. The aim of this study was to characterize subtypes of adrenergic G-protein-coupled receptors and their influence on cAMP concentration and PKA activity in bovine corneal epithelial and endothelial cells. Procedures: Adrenergic receptors and PKA were studied using polyclonal antibodies. cAMP concentration was determined with an enzyme immunoassay, and PKA activity was estimated by the kinases consumption of adenosine triphosphate. Results: In bovine corneal epithelial and endothelial cells, immunocytochemistry and Western blot were positive for α1-, α2A-, β1- and β2-adrenergic receptors. Stimulation of corneal epithelial and endothelial β-adrenoceptors with isoprenaline led to a dose-dependent increase in cAMP concentration and activation of PKA. Stimulation of corneal α2A-adrenoceptors with brimonidine resulted in a dose-dependent decrease in cAMP concentration and the inhibition of PKA activity. Conclusions: In corneal epithelial and endothelial cells, β-adrenergic stimulation leads to activation of PKA via stimulation of adenylyl cyclase, and α2A-adrenoceptor stimulation inhibits PKA activity via inhibition of adenylyl cyclase. Stimulation and inhibition of the corneal cAMP-PKA pathway may play a role in important corneal functions such as wound healing or homeostasis. Long-term therapy with α2A-agonists or β-antagonists may influence these functions in a currently unknown way.

Chameleon-like appearance of immunotactoid keratopathy.

Purpose: To demonstrate 5 different patterns of immunotactoid keratopathy (ITK) in monoclonal gammopathy of undetermined significance (MGUS) that can mimic hereditary and degenerative disorders. First follow-up of 1 female patient was performed. Methods: Colored slit-lamp photodocumentation of 6 MGUS light kappa patients with different types of ITK, one patient with a follow-up of 7 years. Systemic and serological examinations of all 6 patients were performed. Results: The systemic and serological examinations disclosed an MGUS light kappa in all 6 patients. The 7-year follow-up of case 2 showed a reduction of lattice-like opacity to moderate diffuse corneal opacity. Corneal opacity patterns of the 6 patients were as follows: pattern 1, crystalline-like; pattern 2, lattice-like; pattern 3, peripheral granular-like; pattern 4, peripheral band-like; and patterns 5 and 6, peripheral patch-like. Conclusions: ITK of MGUS can mimic cystinosis, Schnyder corneal dystrophy (CD), pre-Descemet CD, lattice CD, granular CD, arcus lipoides, lecithin-cholesterol acyltransferase deficiency, gelatinous drop-like CD, and Salzmann nodular degeneration. ITK can be the first symptom of MGUS. An annual internal check of MGUS is recommended because of occurrence of a systemic monoclonal gammopathy in 20% of cases.