An essential feature of the superposition type of compound eye is the presence of a wide zone, which is transparent and devoid of pigment and interposed between the distal array of dioptric elements and the proximally placed photoreceptive layer. Parallel rays, collected by many lenses, must (through reflection or refraction) cross this transparent clear-zone in such a way that they become focu...

BACKGROUND Cataract surgery techniques have improved a lot over the years from couching to the latest micro-incision cataract surgery. OBJECTIVES To compare the temporal sclero-corneal and clear corneal tunnel incisions in patients undergoing manual small-incision cataract surgery (SICS) with respect to the surgically-induced astigmatism. MATERIALS AND METHODS The present study included 60 ...

BACKGROUND Sclerocornea, a congenital corneal pathology characterized by bilateral scleralization of the cornea, which can be found in few cases with posterior fossa malformationshemangiomas-arterial anomalies-cardiac defects-eye abnormalities-sternal cleft and supraumbilical raphe (PHACES) syndrome. Presence of vascularization in peripheral cornea and smaller diameter of recipient cornea corre...

anatomical structure. Just how far it is or is not vascular in normal man is not completely clear. In certain animals it is a-vascular and in man this is probably so. The abundant vasa vasorum supply the adventitia rather than the intima. In the cornea, lipoid deposition is the last event in a series of changes following chemical damage of various kinds. Let the chemical be called X. The chemic...

THE classical cataract section, either by a von Graefe knife or by a keratome and scissors, is essentially a section in which the cornea is sliced (Fig. 1). An enormous number of techniques has been developed which incorporate this slicing section; these usually involve direct suturing either of the cornea after its section, or of the corneo-scleral margin with or without a flap to cover the in...