The Clinical Study of the Exposure of Implant after Evisceration

PURPOSE: To determine the factors leading to the exposure of porous spherical orbital implants (Hydroxyapatite or Medpor(R)) after evisceration. METHODS: A retrospective analysis of evisceration cases with porous spherical orbital implant performed between January 1998 and August 2002 (n=104). Forty-five patients underwent evisceration with Hydroxyapatite implantation and 59 with Medpor(R) implantation. We analyzed the exposure rate by sex, age, size of implant, kind of implant, with or without drilling, preoperative condition of eyeball, and surgeon. RESULTS: Mean follow-up period was 18.1 months. The sex, age, size of implant, drilling, and preoperative eyeball condition showed no statistically significant difference on exposure rate, but Medpor(R) implant showed a higher exposure rate than Hydroxyapatite. The exposure rate of implant between orbital implants was mostly influenced by surgeon. CONCLUSIONS: The exposure rate of implant was mostly influenced by surgeon's factor, indicating that delicate operative technique for evisceration is necessary.

The Results of Endoscopic Canaliculocystodacryorhinostomy with Two Sets of Silicone Tube Intubation in Canalicular Obstruction

PURPOSE: This study evaluated the effectiveness of endoscopic canaliculodacryocystorhinostomy with two sets of silicone tube intubation in the distal part of canalicular obstruction. METHODS: Endoscopic canaliculodacryocystorhinostomy with double silicone tube intubation was done in 26 patients with canalicular obstruction from January 2002 to December 2002. Probing or trephination was used for recanaliculization of obstructed canaliculi. The silicone tube was left in place for 6 months. RESULTS: The success rate was 76.9% (20 of 26 patients) two months after tube removal. The level of canalicular obstruction or method of bougienage did not affect the success rates. Complications includes granuloma formation (12), synechia of ostium (1), prolepses of tube (2), and acute dacryocystitis(1). CONCLUSIONS: Endoscopic canaliculodacryocystorhinostomy with double silicone tube intubation showed a relatively high success rate and was more effective and convenient than conjunctivodacryocystorhinostomy with Jones tube.

The Change of Interleukin-1beta & Nitric Oxide in Tear after Excimer Laser Photorefractive Keratectomy

This study was performed to investigate the amount of IL-1beta & NO in tear film after Excimer laser PRK and to determine whether NO induces cytotoxicity associated with apoptosis of keratocytes. Twelve myopes underwent PRK and were divided into 3 groups according to spherical equivalent. IL-1beta and NO production were measured at preop and postop 1, 4, 7 days, and expression of NOS and apoptosis of keratocytes were evaluated in the corneas of rats at 2 days after PRK. IL-1beta and NO production were significantly increased at postop 1 day(p<0.01) and then gradually decreased to preop levels at postop 7 days. The corneas of rats at 2 days after PTK revealed increased expression of NOS(iNOS, bNOS) and increased apoptosis of keratocytes in stroma of cornea. The degree of corneal opacity and NO production at postop 1 days were increased, positively correlated to ablation depth. It is suggested that NO production induced by IL-1beta may be related with apoptosis of keratocyte, which can influence on the corneal opacity after PRK.

Comparison of the Retinal Microvasculature between Normal and Diabetic Rats Using Trypsin & DNase Digestion Technique

Trypsin and DNase digestion technique has become a retinal digestion technique for studying diabetic retinopathy. We tried osmotic digestion method with DNase and compared the quality of preparation of retina and microvascular change with trypsin digestion in normal and diabetic rats. Streptozotocin-induced diabetic rats were sacrificed at 9, 18, 27weeks in 6 rats. Right retinas were digested with 3% trypsin while left wer digested with 0.1% DNase. For control, 18 normal rats were sacrificed at the same time. DNase was superior to trypsin for retinal preparation on the stainability, the degree of separating nonvascular fissue from vascular net, the degree of preservation of vascular net in normal & diabetic rats. In diabetic rats, the number of pericyte decreased significantly with age, which not in normal rats(p=0.0023) We suggest DNase digestion technique as an new alternative for trypsin digestion technique in the study of microvascular change of diabetic retinopathy.

Pupil Size in the Dark in Normal Adults

Recently refractive corneal surgery has been increasing and intraocular lens implantation is a routine procedure during cataract surgery. Many people have various activities in the evening such as night driving, thus it may be very important measuring the pupil size in the dark in determining the size of the optical zone. We measured pupil size of sixty normal adult candidates in darkness of 0, 20, 60, 100 lux and also in the bright illumination of 200 lux for comparison using near lens camera and slide film. The pupils became larger with younger age and increased darkness. Pupil Size(log mm) = 4.57 - 0.0388 X Age(year) - 0.005 X Luminance(lux). The average pupil size of all age groups were 7.0mm, 6.56mm, 5.97mm, 5.4mm sequencially in darkness and 4.77mm in brightness(200 lux). The average pupil size of 20~30 year old group who are socially active even at night was 7.18mm and 8.4mm in maximum. This has significant meaning clinically. Additionally the size of pupil became larger with increased corneal diameter and the amount of anisocoria tended to be greater with the increase of the darkness.