Biomedical subjects

C Suvarnamani

Publications and source records attributed to C Suvarnamani.

4 recordsLinked to original sources

PubMed1991

Retinoblastoma manifesting as orbital cellulitis.

Five children with previously undiagnosed retinoblastoma had signs of unilateral orbital cellulitis and were treated with systemic antibiotics, corticosteroids, or both. When retinoblastoma was finally diagnosed clinically, radiologists believed in every case that, on the basis of the soft-tissue swelling seen with computed tomography, there was orbital extension of the tumor. However, intraoperative and histopathologic observations disclosed no demonstrable orbital tumor involvement. The affected eyes all had neovascular glaucoma, and all harbored highly necrotic tumors that were contained within the eye. We concluded that orbital inflammation can occur with retinoblastoma confined to the eye and that signs of orbital cellulitis do not necessarily imply orbital extension of the tumor.

Cellulitis↗

PubMed1991

Orbital exenteration with eyelid sparing: indications, technique, and results.

Of 22 orbital exenterations performed from January 1980 to December 1989, 16 were performed by an eyelid-sparing technique, and six were allowed to heal by spontaneous granulation. Reviewing these procedures, we conclude that the eyelid-sparing method is indicated mainly for advanced primary orbital malignancies and for certain secondary orbital malignancies such as orbital extension of uveal melanoma, conjunctival melanoma, and conjunctival squamous cell carcinoma. It is not usually applicable to orbital invasion of malignant eyelid tumors such as basal cell carcinoma and sebaceous gland carcinoma. Advantages of the eyelid-sparing method are more rapid healing and earlier fitting of a prosthesis.

Aged↗

PubMed1989

The effects of total lymphoid irradiation upon corneal vascularization in the rat following chemical cautery.

The effect of total lymphoid irradiation (TLI), a form of radiotherapy known to suppress the number of circulating lymphocytes, on corneal neovascularization was assessed in rats. The corneas of TLI-treated rats were cauterized with silver/potassium nitrate one day after delivering gamma irradiation in five equal fractions (10 Gy total dose). Corneal neovascularization was assessed quantitatively by computerized image analysis in corneal flat preparations 4 days after corneal injury following perfusion of the circulation with India ink. TLI reduced the total leukocyte, lymphocyte, neutrophil, and platelet counts below preirradiation levels. The number of circulating lymphocytes was reduced more than neutrophils and platelets. TLI caused a predominance of cytotoxic/suppressor lymphocytes. Tissue examinations 4 days after TLI disclosed an absence of the thymus, as well as a markedly reduced number and size of lymph nodes. TLI rats had less corneal vascularization than nonirradiated controls. Our findings are consistent with the hypothesis that leukocytes play an important role in the pathogenesis of corneal angiogenesis following chemical cautery, but this study does not indicate how TLI suppresses corneal neovascularization.

Animals↗

PubMed1988

Quantitation of corneal neovascularization using computerized image analysis.

We have developed a method for quantitating corneal neovascularization, induced in anesthetized rats by silver nitrate/potassium nitrate cauterization, using a LeMont OASYS video input image analyzer. Corneal vessels are visualized by perfusing the upper half of deeply anesthetized animals with a mixture of 10% india ink, 11% gelatin in lactated Ringer's solution. The eyes are then rapidly cooled using a stream of compressed dichlorodifluoromethane (Freon) to solidify the gelatin mixture. Magnified images of flat preparations of the corneas are acquired using a television camera attached to a dissecting microscope. The images are electronically converted to digital form and the digitized data are stored in the image analyzer. The area of the cornea and blood vessels are independently determined by analyzing the digitized data as discrete values of varying shades of gray (gray-scale analysis). The area and gray scale of the injury and its distance from the corneoscleral limbus can also be measured to determine variability of location and intensity of the injury in different animals. This technique allows the area occupied by new blood vessels during studies on corneal neovascularization in rats to be rapidly quantitated.

Animals↗