This review describes a scheme for diagnosis of glaucoma in population based prevalence surveys. Cases are diagnosed on the grounds of both structural and functional evidence of glaucomatous optic neuropathy. The scheme also makes provision for diagnosing glaucoma in eyes with severe visual loss where formal field testing is impractical, and for blind eyes in which the optic disc cannot be seen because of media opacities.

https://bjo.bmj.com/content/bjophthalmol/86/2/238.full.pdf

The definition and classification of glaucoma in prevalence surveys

Tissue sections from aggressive human intraocular (uveal) and metastatic cutaneous melanomas generally lack evidence of significant necrosis and contain patterned networks of interconnected loops of extracellular matrix. The matrix that forms these loops or networks may be solid or hollow. Red blood cells have been detected within the hollow channel components of this patterned matrix histologically, and these vascular channel networks have been detected in human tumors angiographically. Endothelial cells were not identified within these matrix-embedded channels by light microscopy, by transmission electron microscopy, or by using an immunohistochemical panel of endothelial cell markers (Factor VIII-related antigen, Ulex, CD31, CD34, and KDR[Flk-1]). Highly invasive primary and metastatic human melanoma cells formed patterned solid and hollow matrix channels (seen in tissue sections of aggressive primary and metastatic human melanomas) in three-dimensional cultures containing Matrigel or dilute Type I collagen, without endothelial cells or fibroblasts. These tumor cell-generated patterned channels conducted dye, highlighting looping patterns visualized angiographically in human tumors. Neither normal melanocytes nor poorly invasive melanoma cells generated these patterned channels in vitro under identical culture conditions, even after the addition of conditioned medium from metastatic pattern-forming melanoma cells, soluble growth factors, or regimes of hypoxia. Highly invasive and metastatic human melanoma cells, but not poorly invasive melanoma cells, contracted and remodeled floating hydrated gels, providing a biomechanical explanation for the generation of microvessels in vitro. cDNA microarray analysis of highly invasive versus poorly invasive melanoma tumor cells confirmed a genetic reversion to a pluripotent embryonic-like genotype in the highly aggressive melanoma cells. These observations strongly suggest that aggressive melanoma cells may generate vascular channels that facilitate tumor perfusion independent of tumor angiogenesis.

Vascular Channel Formation by Human Melanoma Cells in Vivo and in Vitro: Vasculogenic Mimicry

Background Ocular trauma or disease may lead to severe corneal opacification and, consequently, severe loss of vision as a result of complete loss of corneal epithelial stem cells. Transplantation of autologous corneal stem-cell sources is an alternative to allograft transplantation and does not require immunosuppression, but it is not possible in many cases in which bilateral disease produces total corneal stem-cell deficiency in both eyes. We studied the use of autologous oral mucosal epithelial cells as a source of cells for the reconstruction of the corneal surface. Methods We harvested 3-by-3-mm specimens of oral mucosal tissue from four patients with bilateral total corneal stem-cell deficiencies. Tissue-engineered epithelial-cell sheets were fabricated ex vivo by culturing harvested cells for two weeks on temperature-responsive cell-culture surfaces with 3T3 feeder cells that had been treated with mitomycin C. After conjunctival fibrovascular tissue had been surgically removed from the ocular surfa...

https://www.nejm.org/doi/pdf/10.1056/NEJMoa040455

Corneal reconstruction with tissue-engineered cell sheets composed of autologous oral mucosal epithelium.

An Integrated Hypothesis That Considers Drusen as Biomarkers of Immune-Mediated Processes at the RPE-Bruch's Membrane Interface in Aging and Age-Related Macular Degeneration

https://oftalmologiarafaelcaiado.files.wordpress.com/2012/04/anchor-study.pdf

Ranibizumab versus Verteporfin Photodynamic Therapy for Neovascular Age-Related Macular Degeneration: Two-Year Results of the ANCHOR Study

Using Littmann's method for correcting the magnification of central fundus photographs, we determined the absolute size of 35 unselected optic discs with pseudopapilledema. The optic disc area (1.95 +/- 0.33 mm2 (mean and SD)) was significantly (P less than 0.001, Student's t-test ) smaller than standard values of normal unselected optic nerve heads (2.73 +/- 0.76 mm2). There was no cupping in the discs with pseudopapilledema. Coefficients of variation for intraobserver re-evaluation were 0.045, and for interobserver re-evaluation 0.08. The markedly reduced optic disc size coincide with an abnormally small optic nerve scleral canal may inhibit the intraaxoplasmatic flow with secondary swelling of the juxtapapillary optic nerve fibers. This may lead t o prominence and indistinct borders of the optic disc. Pseudopapilledema might be related to optic nerve head drusen, which are also associated with abnormally small optic discs.

Pseudopapilledema associated with abnormally small optic discs.

Ziel dieser prospektiven Studie war die Prufung der Reproduzierbarkeit eines automatisierten Verfahrens der Hornhautendothelanalyse und die Beurteilung seiner Validitat im Vergleich zu einer Standardmethode. Personen und Methoden: Verwendet wurde ein Kontaktspiegelmikroskop mit integrierter Videokamera (Tomey EM-1000) und ein Computer (IBM kompatibler PC, 486DX33) mit zugehoriger Software (Tomey EM-1100, Version 0.94). Grundprinzip des Verfahrens ist die direkte Uberfuhrung eines Videoendothelbilds (Flache: 0,312 mm2) in ein digitalisiertes Computerbild und dessen automatisierte Prozessierung unter Umgehung einer Filmvorlage. Die Methode wurde bei 67 Probanden mit unauffalliger Hornhaut (Alter: 30,9±8,6 Jahre) angewendet. Bei 42 Normalprobanden wurde die Zelldichte 3mal von demselben Untersucher (Retest-Stabilitat), bei 25 Probanden je 1mal von 3 verschiedenen Untersuchern (Objektivitat) bestimmt. Festgehalten wurden der nach Analyse des Rohbilds vom Rechner ermittelte Zelldichtewert sowie ein 2. Wert nach Korrektur des prozessierten Bilds durch den Untersucher. Zusatzlich wurde die Endothelzelldichte anhand von Photographien (Spiegelmikroskop Bio Optics LSM 2000 A) in Fixed-frame-Technik durch manuelles Auszahlen ermittelt (Validitat). Ergebnisse: Bezuglich der korrigierten Zelldichtewerte waren sowohl die Reteststabilitat (Reliabilitatskoeffizient r = 0,943) als auch die Objektivitat (r = 0,904) hoch. Die Werte der automatisierten Methode (2415±214 Zellen/mm2) und nach manuellem Auszahlen (2431±228 Zellen/mm2) waren nicht signifikant verschieden (p = 0,898). Die mittlere Abweichung betrug 3,3±2,4%, wobei keine systematische Abweichung in eine Richtung vorlag. Die unkorrigierten Zelldichtewerte (2252±190 Zellen/mm2) lagen im Mittel um 7,2±2,6% unter den korrigierten. Bezuglich der unkorrigierten Werte waren die Reteststabilitat (r = 0,856) und die Objektivitat (r = 0,737) zufriedenstellend. Der unkorrigierte Wert war gegenuber dem durch manuelles Auszahlen ermittelten Wert signifikant erniedrigt (p<0,001). Schlusfolgerung: Das getestete Endothelanalyseverfahren liefert bei normaler Hornhaut schnell zuverlassige und reproduzierbare Ergebnisse, vorausgesetzt, das vom Korrekturmodus der Software Gebrauch gemacht wird.

Reproduzierbarkeit und Validität eines neuen automatisierten Verfahrens der spiegelmikroskopischen Hornhautendothelanalyse

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

A 37-year-old man with coarse facies, stiff joints, corneal clouding, and normal intelligence sought medical attention. The diagnosis of a systemic mucopolysaccharidosis (MPS) type I-S (Scheie's syndrome) was confirmed by the presence of lysosomal alpha-L-iduronidase deficiency and excessive urinary dermatan and heparan sulfate excretion. The corneal button after perforating keratoplasty of the right eye demonstrated mucopolysaccharides consisting of numerous vacuoles containing fibrillogranular and partly membranebound material in epithelial cells, histiocytes, keratocytes, and extracellular matrix. Endothelial cells were distinctly free of storage material. The epithelial basement membrane showed frequent breaks, whereas Bowman's layer was only slightly attenuated. Irregular collagen fibrils and fibrous long-spacing collagen were noted near degenerating distended keratocytes. The Descemet's membrane was normal. The literature of six reported histopathological examinations of the cornea in Scheie's syndrome is reviewed. Detection of fibrous long-spacing collagen seems to be a typical abnormality of the cornea in MPS I-S.

Gottfried O. H. Naumann

Papers

Pseudopapilledema associated with abnormally small optic discs.

Reproduzierbarkeit und Validität eines neuen automatisierten Verfahrens der spiegelmikroskopischen Hornhautendothelanalyse

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

Light and electron microscopy of the cornea in systemic mucopolysaccharidosis type I-S (Scheie's syndrome).

Clinical and morphological response to UV-B irradiation after excimer laser photorefractive keratectomy.