Reduction of Blue Light Emission in Internet-protocol Television and Its Effect on Ocular Fatigue

PURPOSE: The blue light emitted from electronic devices may be harmful to the eye. We investigated whether internet-protocol television (TV) with lowered blue light emission reduced ocular fatigue. METHODS: A total of 98 healthy subjects were recruited. They watched an animated movie (A) and an identical version except for reduced blue light (B), sequentially for 1 hour in random order. Before and after watching the movies, we measured the distance and near refraction and tear break-up time objectively. Ocular discomfort score and the earliest onset time of the ocular fatigue symptoms were also measured using our specially designed subjective ocular discomfort scale. RESULTS: The median age of the participants was 28.5 years, and there were 56 females out of 98 total participants. Both distance and near refraction were not significantly different before versus after watching the movies, nor between viewing movies A and B. However, the accommodative amplitude measured by subtracting the near refraction from the distance refraction was found to be greater after watching movie B compared with movie A in a subset of subjects with hyperopia [1.92 vs. 1.72 diopters (D) for the right eye and 2.14 vs. 1.83 D for the left eye; p = 0.04 and p < 0.01, respectively]. The ocular discomfort score was lower (15.40 vs. 12.85; p = 0.10), but not significantly, and the earliest ocular fatigue onset time was significantly delayed (23.48 vs. 34.51 minutes; p < 0.01), after watching movie B. CONCLUSIONS: Reduction of blue light emission alleviated ocular fatigue caused by TV displays. Watching TV with lower blue light may provide benefits to hyperopic individuals by reducing eye strain and improving the accommodative amplitude.

Absorption Rates of Various-thickness Human Acellular Dermal Grafts(SureDerm(R))

The human acellular dermal graft provides safe and lasting volume gain for soft tissue augmentation in the face. However, variable amounts of the graft are gradually reabsorbed in the host tissue. The purpose of this experiment is to evaluate the absorption rates of the implanted acellular dermal grafts (SureDerm(R)) and to estimate the amount of overcorrection in the soft tissue augmentation. Twenty-eight New Zealand white rabbits were divided into 4 groups. A 2.0x 2.5 cm sized subcutaneous pocket was created on the dorsal surface of the ear. 10x10 mm sized SureDerm(R) sheets, each 1 mm, 2 mm, 3 mm and 4 mm in thickness were implanted into the pockets. Ear thickness was measured by Thickness Gauze at the time of pre-operative, immediate post-operative, 4, 8 and 12 weeks after implantation. Full thickness ear was harvested in 4, 8 and 12 weeks and examined histologically for graft thickness, host tissue ingrowth, neocollagen synthesis and inflammatory reaction. Ear thickness was mildly increased due to swelling and inflammatory reaction in the initial 4 weeks in all groups and then was decreased in 12 weeks by 84%. However, there was a significant decrease in the thickness of the graft itself (43%). There was no significant difference in the ear thickness among the groups (p<0.05) with time. Histological analysis of implanted SureDerm(R) sheets demonstrated progressive neovascularization, fibroblast infilteration, neocollagen bundle synthesis and organization. Our experimental study suggests that the absorption rate of SureDerm(R) is quite uniform regardless of the thickness of the graft. The amount of overcorrection is relatively predictable and 18% of overcorrection seems to be needed for satisfactory result.

The Effect of Duration of Lipo-PGE1 Administration on Flap Survival in a Rat TRAM Model

This study was designed to find out an effective duration of pharmacological delay using Lipo-PGE1 to prevent the ischemic compromise of TRAM flap in rats. Fifty Sprague-Dawley rats were divided into 5 groups evenly and a left inferior epigastric vessel pedicled TRAM flap, sized 5.0 X 3.5 cm was created on the abdomen. Experimental groups included group I(control): no procedure before the flap elevation; group II, III, IV and V(pharmacological delay groups): Lipo-PGE1(0.5mug) was given daily intraperitoneally for 3, 5, 7 and 14 days before the flap elevation. On the seventh day after the operation, we evaluated and compared the results of flap survival rate, vessel distribution through Barium microangiography and histological findings by the hematoxylin-eosin stain and the VEGF immunohistochemistry. The results were as follow: 1) The mean percentage of the flap survival area of group II(52.84 +/-27.03%), III(63.15+/- 16.57%), IV(63.53+/- 13.15%), V(61.44+/- 17.17%) were higher than that of group I(30.42 +/- 14.58%) significantly (p < 0.05). 2) The vessel distribution of the pharmacologic delay groups were more abundant than that of the control group. 3) the vascularity of the pharmacological delay groups were more diffused than that of the control group in the hematoxylin-eosin stain. 4) There was no difference in the expression of VEGF protein within the endothelial cell between the control and the pharmacological delay groups. In conclusion, the use of Lipo-PGE1 for a relatively short term period(about 3-5 days) could remarkably increase the flap survival area in rat TRAM model compared to the surgical delay(2 weeks).

A Case of Dermatofibrosarcoma Protuberans in a Breast

Dermatofibrosarcoma protuberans is a moderate degree malignant tumor that has high recurrent rate and low metastatic rate. This occurs most frequently on the trunk, the proximal part of upper limbs and lower limbs. However, the occurrence of this disease in the breast is extremely rare. Our case is a 20-years-old female patient who has a non-elevated nodule in the lower part of right breast. The mass was lobulated and relatively fixed to skin, but movable. The color of the overlying skin was reddish purple. The biopsy showed characteristic storiform pattern of the spindle cells on the H-E stain, and positive and negative stain on the immunohistochemical stain of anti-CD34 antibody and S-100 protein respectively. Based on the above findings we confirmed dermatofibrosarcoma protuberans (DFSP) and did wide excision for preventing recurrence and reconstructed the breast using a pedicled latissimus dorsi musculocutaneous flap. F-U taken 11 months after the operation shows no recurrence and good cosmetic result without deformity of breast or donor site morbidity.

A Case of Malignant Clear Cell Hidradenoma

Malignant clear cell hidradenoma is a rare eccrine gland malignancy characterized by a solitary nodule on the head, trunk or distal extremity. We report a case of malignant clear cell hidradenoma in the left sole of a 66 year old female patient. Despite wide resection, regional lymph node dissection and radiation therapy, wide spread regional invasion and multiple distant metastasis were developed. As the malignant clear cell hidradenoma is reported rarely in the world and not yet reported in Korea, we report its clinical process of the diagnosis and treatment to patient's death.