Jpn J Ophthalmol 43, 565–572 (1999)© 1999 Japanese Ophthalmological SocietyPublished by Elsevier Science Inc. 0021-5155/99/$–see front matter

ABSTRACTS

Comparison of Stromal Remodeling and Keratocyte Response After Corneal Incision and Photorefractive Keratectomy

Purpose:

We investigated the keratocyte responseand stromal remodeling after corneal incision andphotorefractive keratectomy, respectively to learnthe difference between the two surgeries histophysi-ologically and immunohistochemically.

Methods:

We performed corneal incision or photo-refractive keratectomy in rabbits or rats, and thenwe chronologically observed the histological changesand the changes in localization of extracellular ma-trix proteins.

Results:

In both types of surgery, the keratocyte pop-ulation in the damaged stroma became sparse, andthe cells were undergoing apoptosis immediately afterthe procedures. After that, activated keratocytes mi-grated into the acellular zone, and the cells formedmultiple layers at the resurfaced subepithelial regions.Deposition of amorphous substances was observedbetween migrated keratocytes, and stromal remodel-ing began. Three months after the surgery, cornealstructure had recovered to near normal condition inthe corneal incisions. In photorefractive keratectomy,however, strong immunoreactivity of extracellular ma-trix proteins was observed in the subepithelial regions.

Conclusions:

These results suggested that stromalwound healing processes were similar in both cor-neal incision and photorefractive keratectomy. Cor-neal incision may induce transient keratocyte responseduring the stromal remodeling, but photorefractivekeratectomy may induce sustained keratocyte re-sponse. (J Jpn Ophthalmol Soc 103:337–349, 1999)

Toshiro Tanaka

Department of Ophthalmology, Yamaguchi University School of Medicine

PII S0021-5155(99)00120-3

Morphological Changes in Rabbit Corneal Endothelium After Surgical Injuries

Purpose:

To understand the responses of the cornealendothelium to different types of surgery, we chro-nologically investigated the morphologic changes inthe endothelial cells.

Methods:

We did a mechanical incision, epithelialablation, and excimer laser radiation on rabbit cor-neas and observed the morphologic changes in theendothelial cells for up to 2 weeks after surgery un-der a light microscope and an electron microscope.

Results:

Although we observed enlarged intercellu-lar spaces between neighboring endothelial cells, in-tercellular adhesion kept the cells tightly joined neartheir apexes immediately after each procedure. Nosigns of endothelial cell degeneration were observedafter the procedures, but we did observe many Golgiapparati, rough-surfaced endoplasmic reticula, andsecreted granules, indicating that the cells had beenactivated. After each procedure, the intercellularjunctions and spaces required different amounts oftime to return to normal.

Conclusions:

These results suggest that the differentkinds of surgical injuries affected the corneal endo-thelium but that the changes were reversible. (J JpnOphthalmol Soc 103:350–355, 1999)

Masanori Miyazaki,*

†

Toshiro Tanaka* and Teruo Nishida*

*Department of Ophthalmology, Yamaguchi University School of Medicine;

†

Current Affiliation: Department of Ophthalmology, Faculty of Medicine, Kyushu University

PII S0021-5155(99)00121-5

The Effect of Neurotransmitters onRabbit Cornea

Purpose:

To ascertain the effect of neurotransmit-ters added to the culture medium of rabbit cornealepithelium and stromal cells.

Method:

The corneal epithelium and stromal cellswere cultured in RCGM medium. Three neurotrans-mitters were added to the medium: substance P, ace-tylcholine, and vasoactive-intestinal peptide (VIP).

Abstracts of Published Articles in

Nippon Ganka Gakkai Zasshi (Journal of the Japanese Ophthalmological Society)