Biomedical subjects

K C Yoon

Publications and source records attributed to K C Yoon.

10 recordsLinked to original sources

PubMed2001

Electroretinographic studies in rhegmatogenous retinal detachment before and after reattachment surgery.

Changes in the scotopic electroretinogram (ERG) and oscillatory potentials (Ops) were examined in patients who had rhegmatogenous retinal detachment within 3 days before and also at regular intervals after a successful reattachment operation. Electroretinograms were recorded in 38 patients (age 10 to 62 years) for the recent 5 year period. The amplitudes of the scotopic a-wave and b-wave in the detached eye were significantly decreased compared to the fellow normal eye preoperatively. Statistically significant differences were found between the preoperative and the postoperative recordings of the diseased eye. However, postoperative interocular differences in the amplitude of the a-wave between the reattached and normal fellow eye were not statistically significant. The amplitudes of the a-wave and b-wave were inversely related to the extent of the retinal detachment area, the duration of the detachment, and the extent of the buckles that were applied. Significant interocular differences in the b/a wave amplitude ratio and the Ops amplitude were observed. These results strongly suggest that the retinal function, even after successful reattachment surgery, might be compromised mainly by an inner retinal malfunction rather than from a photoreceptor dysfunction.

Adolescent↗

PubMed1998

Systematic approach and selective tissue removal in blepharoplasty for young Asians.

Although the double eyelid operation was initially designed to create supratarsal folds in Asians, it has evolved into a cosmetic procedure to make Asian eyelids more aesthetically pleasing. Therefore, it is appropriate to call it "blepharoplasty for young Asians." All the candidates for this operation desired natural-looking attractive eyelids with double folds, which is far from puffiness and severe epicanthus. Two hundred forty-one patients underwent "blepharoplasty for young Asians" from 1991 to 1996 at Asan Medical Center, and they were performed by one surgeon (Yoon). A systemic approach has been adopted for the procedure: first, the size of the folds is determined; second, debulking of the upper eyelids and handling of the epicanthus is taken into consideration in relationship with future folds. In addition to creating folds, half Z-plasty is used to alleviate the epicanthus, and a selective tissue removal technique is applied to titrate the amount of puffiness in the upper lids.

Adipose Tissue↗

PubMed1998

A new technique for repositioning a posteriorly dislocated intraocular lens.

Pars plana vitrectomy was performed to treat a complete posterior dislocation of an intraocular lens in seven patients. The method that the authors have developed appears to be safer and simpler than those previously described. The haptics are externalized for a secure tie at the proper site, and are then reinternalized back through the pars plana sclerotomies. Only two small needle perforations are made for the scleral fixation of the intraocular lens in the ciliary sulcus. Perfluorocarbon liquid is used to prevent intraoperative retinal damage.

Fluorocarbons↗

PubMed1997

Dapsone maculopathy.

After the injection of about 10 gm of dapsone, a 38-year-old male showed a whitish-yellow patch in the macular region of both eyes, with decreased visual acuity of the counting finger in the right and 0.04 in the left eye. Two weeks after the start of systemic steroid therapy the patch disappeared, and on follow-up at 11 months, visual acuity was 0.02 in the right and 0.08 in the left eye, with macular degeneration and foveal nonperfusion. This retinal damage seems to be ischemic in origin and to be caused by a combination of acute severe peripheral hypoxemia and the vascular obstructive effect of red cell fragmentation resulting from massive hemolysis.

Adult↗

PubMed1994

Aconite induced myelo-optic neuropathy in a rabbit model.

Aconite is a common remedy of herb doctors and is widely used in the Far East. Clinical aspects of the visual disturbance produced by this drug have been described, but little is known about its pathology. Tinctura aconiti (0.6 mg of total alkaloid/kg 2x) was administered intraperitoneally in rabbits to evaluate its toxic effects on the visual system. The alteration in the visual evoked potential following aconite injection consisted of a delay in the onset and peak latency. Histopathologically, there were damages to the myelin sheath of the visual pathway, spinal cord and peripheral nerves. These findings suggest that aconite may cause primarily myelo-optic neuropathy.

Aconitum↗

PubMed1972