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Seung Min Lee

Publications and source records attributed to Seung Min Lee.

5 recordsLinked to original sources

Clinical Utility of Ultra-Widefield Swept-Source OCT for Intraocular Tumors: Comparison With Ultrasonography, SD-OCT, and MRI.

PURPOSE: To evaluate the clinical performance of ultra-widefield swept-source optical coherence tomography (UWF-OCT) in the assessment of choroidal tumors and to compare it with ultrasonography (US), spectral-domain (SD)-OCT, and magnetic resonance imaging (MRI). DESIGN: Retrospective diagnostic comparison. SUBJECTS: Thirty-nine eyes from 39 patients diagnosed with choroidal tumors at a single tertiary referral center. METHODS: This retrospective diagnostic comparison evaluated patients diagnosed with choroidal tumors at a single tertiary referral center between January 2023 and August 2025. All patients underwent UWF-OCT imaging at diagnosis. Tumor measurements obtained with UWF-OCT were compared with US, SD-OCT, and MRI. Comparative analysis among imaging modalities and predictors affecting UWF-OCT applicability was performed. MAIN OUTCOME MEASURES: Tumor thickness (mm) and largest basal diameter (LBD, mm) measurements, and complete measurability rate across different tumor size categories. RESULTS: Thirty-nine eyes from 39 patients (mean age 59.2 &#xb1; 16.9 years) were analyzed, including 27 choroidal melanomas (69.2%), 5 metastatic tumors (12.8%), 4 hemangiomas (10.3%), 2 osteomas (5.1%), and 1 (2.6%) indeterminate choroidal melanocytic lesion. UWF-OCT successfully measured both tumor thickness and largest basal diameter (LBD) in 100% (31/31) of small and medium choroidal tumors, substantially outperforming SD-OCT (complete measurement achieved in 63.6% of small tumors, and 0% of medium or large tumors). UWF-OCT measurements were systematically smaller than ultrasonography (thickness: -32.3%, P < .01; LBD: -11.1%, P < .01) and MRI (thickness: -29.2%, P < .01). Mushroom-shaped tumor morphology was the strongest negative predictor of UWF-OCT quality (OR = 0.015, 95% CI 0.001-0.196, P < .01). UWF-OCT's complete measurability was limited in large tumors (12.5%, 1/8). CONCLUSIONS: UWF-OCT provides precise, noninvasive, single-scan assessment of small-to-medium choroidal tumors with detailed structural visualization. It may be particularly useful for dome-shaped tumors, while multimodal imaging with US and MRI remains optimal for complex morphologies. Overall, UWF-OCT represents a valuable tool for diagnosis and treatment planning, with potential utility for longitudinal follow-up in choroidal tumor management.

Humans↗

Melatonin protects against neuronal damage induced by 3-nitropropionic acid in rat striatum.

In this study, the protective effects of melatonin were evaluated against 3-nitropropionic acid (3-NP)-induced striatal neuronal damage in rats. Lesions were induced in the right striatum of Sprague-Dawley rats by stereotaxic injection with 3-NP and melatonin was intraperitoneally administered both 30 min before and 60 min after 3-NP injection. And rats continuously received melatonin daily for 3 days. As indicators of oxidative damage, lipid peroxidation and protein oxidation in the lesioned striatum were measured at 1 day after 3-NP injection. Levels of malondialdehyde (MDA) and protein carbonyl were significantly increased by 3-NP injection, but reduced in the melatonin-treated rats. Four days post-lesion, large lesions and extensive neuronal damage were produced in the 3-NP-injected striata, as revealed by 2,3,5-triphenyltetrazolium chloride (TTC) staining. In addition, marked ipsilateral rotational behavior following apomorphine challenge and a decrease of dopamine content in the lesioned striatum were observed in the 3-NP-injected rats. However, melatonin treatment significantly attenuated the 3-NP-induced neuronal damage, reduced the degree of asymmetric rotational behavior, and restored the dopamine level in the lesioned striatum. The present results indicate that melatonin effectively protects against the neuronal damage caused by 3-NP in vivo and that the neuroprotective effects of melatonin may be related to antioxidant action.

Analysis of Variance↗

Partial corpectomy for cervical spondylosis.

STUDY DESIGN: A retrospective review was performed of a single surgeon's experience with partial corpectomy over a 9-year period. The measures evaluated included fusion rate, complications, and neurologic symptoms. OBJECTIVE: To demonstrate the safety and efficacy of partial corpectomy for multilevel cervical spondylosis. SUMMARY OF BACKGROUND DATA: Strategies for the surgical management of cervical spondylosis have included laminectomy, multilevel corpectomy, and multilevel discectomy. All have significant disadvantages, including high nonunion rates and late deformity. A procedure incorporating multilevel discectomy, partial corpectomy, strut graft, and plating is described. By removal of the anterior two thirds of the intervening vertebral body, visualization of the interface between the dura and the disc or PLL is enhanced, and osteophytes can be easily removed. Fusion rates are improved. METHODS: All partial corpectomy cases with a 2-year follow-up evaluation managed by the senior author for multilevel cervical spondylosis from 1991 to June 1999 were reviewed for the number of levels decompressed, graft source, use of plating, fusion success, and neurologic status. RESULTS: Most of the patients (n = 97) were managed with two-level discectomies, with 42 requiring treatment of three levels and 5 requiring treatment of four or more levels. Allograft was used in 60%. The remainder received iliac crest bone graft. The majority (81%) were plated. Of the cases with 2-year follow-up evaluation, the fusion rate was 95.8%, independent of the number of levels fused. Among the 11% who had continued problems, most had improved. Nonunions were higher in smokers. CONCLUSIONS: Partial corpectomy is an effective strategy for treating multilevel cervical disc disease. It is associated with a high fusion rate. In addition, partial corpectomy facilitates a complete decompression by providing excellent visualization of the dural interface.

Adult↗

A prospective randomized controlled clinical trial comparing the effects of somatostatin and vasopressin for control of acute variceal bleeding in the patients with liver cirrhosis.

BACKGROUND: Acute variceal bleeding is a serious complication of liver cirrhosis, which has an attendant mortality of approximately 60% over two years, and a variety of treatments, such as balloon tamponade, endoscopic varix ligation, sclerotherapy, histoacryl injection and vasoactive drugs, have been used. The aims of the present trial were to compare the effectiveness and complications of somatostatin and vasopressin in the treatment of acute variceal bleeding. METHODS: Forty-three cirrhotic patients, with endoscopically proven acute variceal bleeding, were included in this trial. Both drugs were given as continuous intravenous infusions for 48 hours. Twenty patients received the somatostatin (250 mcg per hr after a bolus of 50 mcg) and twenty-three the vasopressin (0.4 units per min). RESULTS: There were no significant differences between the two groups in relation to age, sex, etiology of cirrhosis, Child-Pugh classification, characteristics of bleeding episode, laboratory findings before randomization and units of transfused blood during therapy. Rebleeding, within 6 hours after beginning of therapy, was regarded as failure to control initial bleeding, and was observed in 3 (13.0%) of the patients who received vasopressin and in 1 (5.0%) treated with somatostatin (p > 0.05). Five patients in both the somatostatin (25.0%) and vasopressin (21.7%) groups rebled during the first 5 days following the initial therapy (p > 0.05). Meaningful complications related to the use of vasopressin were observed in 5 patients (chest pain or abdominal pain requiring nitroglycerin), but no complications were associated with the use of somatostatin (p < 0.05). The mortalities during hospitalization were similar in both the treatment groups. Two of the vasopressin and 1 of the somatostatin group died due to the uncontrolled rebleeding, and 1 of the vasopressin group died due to hepatic failure (2 weeks later after therapy). CONCLUSION: This study showed no differences in the effectiveness of somatostatin and vasopressin, but the somatostatin group had a lower risk of the complications.

Esophageal and Gastric Varices↗