Deletion of 13q in two patients with retinoblastoma, one probably due to 13q-mosaicism in the mother.

We examined the peripheral blood chromosomes of eight patients with retinoblastoma. In two of them an interstitial deletion of 13q was found. The breakpoints were determined as follows: case 1, 13q12 leads to 21; case 2 13q12 leads to 31.

Familial band--shaped keratopathy and spheroidal degeneration. Clinical and electron microscopic study.

Presumptive primary band-shaped keratopathy was described in a 35-year-old man and his 62-year-old paternal uncle. Lamellar keratoplasty was performed in one eye in each of these patients. The light and electron microscopic studies were carried out on both corneal specimens.

Corneal superficial unwettable defect. I. Clinical and histopathological study.

In 11 patients, the clinical, histological and histochemical picture of an unusual corneal affection termed "corneal superficial unwettable defect", is reported. It develops during the healing of various corneal lesions. Clinically, it is described as a defect of the epithelium with a denuded and changed Bowman's membrane, the surface of which repells tears and cannot be stained with fluorescein.

Incipient atrophy of cornea. Experimental study.

The essence of the process in which the corneal tissue disappears in atrophy of the eye has not yet been studied. The authors of this investigation studied the changes in cornea as they developed after a gross perforating injury to the eye in rabbit. They found that the diameter of the cornea had grown smaller by 2 mm and its radius by 0.

Corneal superficial unwettable defect. II. Electron microscopic study.

Corneal biopsy specimens of 6 patients with this particular affection were studies with the electron microscope. In addition to the routine electron microscopic methods, staining with ruthenium red was performed on one excised specimen. Marked changes were found in the region of Bowman's membrane, which was altered either superficially or in its total width.