Corneal Morphology (corneal + morphology)

Distribution by Scientific Domains


Selected Abstracts


In vivo corneal confocal microscopy in keratoconus

OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2005
Joanna G. Hollingsworth
Abstract Purpose:, To evaluate the corneas of keratoconic subjects using in vivo confocal microscopy. Methods:, Slit scanning confocal microscopy was used to evaluate the central cornea of one eye of each of 29 keratoconic subjects (mean age 31 ± 10 years; range 16,49 years). Quantitative aspects of corneal morphology were compared against data from control subjects. Results:, Compared with normal control corneas, epithelial wing cell nuclei were larger (p < 0.0001) and epithelial basal cell diameter was larger (p < 0.05) in the keratoconic cornea. Many of the keratoconic corneas investigated showed increased levels of stromal haze and reflectivity, which appeared to be related to the presence of apical scarring on slit lamp examination. A grading scale was devised to quantify the levels of haze. This scale was shown to provide a measure of the level of scarring present. The anterior keratocyte density (AKD) and posterior keratocyte density were 19% lower (p < 0.0001) and 10% lower (p = 0.004) than in controls, respectively. The reduction in AKD was significantly associated with three factors: a history of atopy, eye rubbing and the presence of corneal staining. The mean endothelial cell density in keratoconus was 6% greater than that of normal controls (p = 0.05). The level of endothelial polymegethism was shown not to be different between keratoconic subjects and matched controls (paired t -test: t = 1.82, p = 0.08). Conclusions:, Confocal microscopy demonstrates significant quantitative alterations of corneal morphology in keratoconus. [source]


4131: Pathologic epithelial and anterior corneal nerve morphology in congenital aniridic keratopathy

ACTA OPHTHALMOLOGICA, Issue 2010
P FAGERHOLM
Purpose To document corneal morphology in Swedish families with congenital aniridia. Methods Detailed ophthalmic examinations were conducted in a number of affected and unaffected members. Digital slit lamp photography, anterior segment optical coherence tomography (ASOCT) and in-vivo confocal microscopy (IVCM) examinations were performed bilaterally to document corneal morphology. Results Affected family members presented with different stages of aniridic keratopathy, with a corneal appearance varying from totally transparent to opaque and highly vascularised. Increased corneal thickness in affected members, particularly those with severe keratopathy, was noted by ASOCT. By IVCM, opaque corneas were characterized by active vessels and dense inflammatory cell infiltration. In corneas with milder keratopathy, pathologic epithelial findings included epithelial pleomorphism, focal epithelial opacities, and an absence of limbal epithelial crypts and focal stromal projections at the limbus. Nerves of the anterior cornea exhibited several distinct features, including an unusually close association of subbasal nerves with epithelial cells, an unusually high subbasal nerve density with highly branched nerves, and a prominent whorl region. Additionally, abnormally dense and tortuous anterior stromal nerves, attached to stromal keratocytes, were noted in unaffected members. Conclusion Altered epithelial morphology and a vigorous innervation of the anterior cornea were the most pronounced corneal findings in family members with milder forms of aniridic keratopathy. Further findings confirmed the known increase in corneal thickness and limbal stem cell abnormality in aniridia. [source]


4333: How does scleral buckling affect the anterior segment of the eye?

ACTA OPHTHALMOLOGICA, Issue 2010
FJ ASCASO
Purpose To describe the modifications produced in the anterior segment of the eye after placing an encircling scleral buckling (SB) in terms of corneal morphology, biomechanics and intraocular pressure. Methods A prospective study of 15 eyes with rhegmatogenous retinal detachment who underwent pars plana vitrectomy combined with a scleral buckle (PPV/SB), and 12 eyes with vitreous hemorrhage treated with PPV alone. We measured preoperatively and 1-month after surgery the corneal biomechanical properties using the Ocular Response Analyzer (ORA), including corneal hysteresis (CH), corneal resistance factor (CRF), intraocular pressure (IOPg), and corneal compensated IOP (IOPcc). Moreover, we defined the corneal morphology by 4 parameters provided by the topographer Orbscan IIz: mean corneal power (dioptres), standard deviation, thinnest point (µm), and anterior chamber depth (ACD) (mm). Results Mean CH values were significantly diminished following PPV/SB (p=0.003). We found no significant changes in CRF. IOPg and IOPcc mean values were significantly increased only in the PPV/SB group (p=0.019 and p=0.010, respectively) but not in PPV group (p=0.715 and p=0.273, respectively). In PPV/SB group, IOPcc mean values were significantly higher than IOPg before (p=0.001) and after surgery (p=0.003), but not in the other group. None of the morphological parameters were modified after surgery in any of the two study groups (p>0.05) Conclusion Anterior segment morphology was not modified after placing a SB. Corneal biomechanical properties showed a reduction in CH, probably due to a vascular constriction and reduction of the eye compliance. PPV might be considered a less invasive approach for the repair of noncomplex retinal detachments than PPV/SB. [source]


Dystrophia Helsinglandica , corneal morphology, topography and sensitivity in a hereditary corneal disease with recurrent erosive episodes

ACTA OPHTHALMOLOGICA, Issue 4 2010
Waldir Neira
Abstract. Purpose:, The aim of this study was to describe the morphology, corneal topography and sensitivity in individuals with Dystrophia Helsinglandica. This autosomal dominant corneal disease is characterized by recurrent corneal erosive episodes and progressive subepithelial fibrosis not significantly affecting visual acuity. Methods:, The corneas of nine affected and nine unaffected individuals were examined using slit-lamp biomicroscopy, in vivo confocal microscopy (IVCM) and videokeratography. Corneal mechanical sensitivity was also measured using a non-contact esthesiometer. Results:, Slit-lamp biomicroscopy revealed that the affected individuals represented different stages of corneal changes, from a nearly normal cornea to subepithelial fibrosis of the central cornea. Corneal changes in affected individuals did not significantly decrease the best spectacle-corrected visual acuity. In vivo confocal microscopy detected morphological changes in the epithelium and stroma. Subepithelial opacity formation including altered keratocytes could be found in the anterior stroma in all affected eyes. With the exception of two eyes (one affected and one unaffected), all videokeratographies showed irregular astigmatism. Corneal sensitivity was significantly lower in affected individuals (p = 0.01). Age and corneal sensitivity showed no correlation. Conclusion:, The main morphological findings in affected individuals were discrete and progressive subepithelial fibrosis, in the in vivo confocal microscope corresponding to optically dense extracellular matrix and activated keratocytes. Subbasal nerve morphology was changed in the affected family members who also showed a decreased corneal sensitivity. The findings are per se not specific to the disease. The changes probably reflect a healing response to erosive events on the corneal surface influenced by the genotype. [source]