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Dive into the research topics where Helen Lew is active.

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Featured researches published by Helen Lew.


Ophthalmologica | 2002

Effect of Botulinum Toxin A on Facial Wrinkle Lines in Koreans

Helen Lew; Young Soo Yun; Sang Yeul Lee; Sung Joo Kim

Two kinds of botulinum toxin type A were clinically evaluated in rhytidectomy. Twenty Korean patients with facial wrinkles were fully assessed following treatments with random injections. The mean degree of wrinkles before the injections was 2.83 and the mean corrective effect was 70.0% at least 3 months afterward. The effect lasted less than 6 months in only 9 cases. The complications were tingling sensations in 3 cases (15.0%), temporary lid swelling in 5 cases (25.0%) and lagophthalmos in 3 cases (15.0%). No serious or permanent adverse effects were observed. Botulinum toxin type A rhytidectomy was a very effective method of removing various facial wrinkles although the treatment for complications and side effects will need to be considered.


Japanese Journal of Ophthalmology | 2002

Complications in motility peg placement for hydroxyapatite orbital implant in anophthalmic socket

Sang Yeul Lee; Jae Woo Jang; Helen Lew; Sung Joo Kim; Hyeyoung Kim

PURPOSE In a retrospective study, we evaluated the complications in using the motility peg system (nonsleeved and sleeved) for hydroxyapatite orbital implants in an anophthalmic socket. METHODS Drilling for motility peg placement was performed in 265 patients with hydroxyapatite implantation: nonsleeved peg system (n = 191), sleeved peg system (n = 74). A statistical analysis was performed using the chi-square test. RESULTS Extrusion rates were significantly lower in the sleeved peg system (10.8%) compared to the nonsleeved peg system (27.2%) (P =.005). The other complications related to motility peg placement were granulation tissue overgrowth (4.2%), hydroxyapatite exposure around peg head (3.0%), and decentered peg (1.9%). CONCLUSIONS To minimize peg extrusion, the sleeved peg was better than the nonsleeved peg for use in primary motility peg placement.


Acta Ophthalmologica | 2013

Tear production and drainage after botulinum toxin A injection in patients with essential blepharospasm.

Hyun Min Shin; Sang Yeul Lee; Helen Lew

Purpose:  To evaluate the clinical manifestations of tear production, distribution and drainage in the essential blepharospasm patients, and to analyse the changes after botulinum toxin A injection in these patients.


Ophthalmologica | 2004

Measurement of pH, Electrolytes and Electrophoretic Studies of Tear Proteins in Tears of Patients with Dacryoliths: A Novel Concept for Dacryoliths

Helen Lew; Sang-Yeul Lee; Yong-Soo Yun

Dacryolithiasis is one of the causes of acquired nasolacrimal duct obstruction, although its origin is unclear. The purpose of this study was to investigate the differences in tear constituents between patients with nasolacrimal duct obstruction with dacryoliths and those without dacryoliths. In a prospective case-control study, undiluted tears were collected from 30 eyes from 30 patients with partial acquired nasolacrimal duct obstruction (PANDO) consisting of 17 PANDO patients with dacryoliths and 13 PANDO patients without dacryoliths. The pH, and the Na+, K+, Cl–, total calcium and total protein concentrations were determined. The composition of the tear proteins was assessed by cellulose acetate electrophoresis. In the tear samples from 17 eyes with PANDO/dacryoliths, the mean ± SD K+ level was 15.6 ± 3.1 mEq/l. In the tear samples from 13 PANDO controls, the mean ± SD K+ level was 19.8 ± 4.9 mEq/l. The difference between the two groups was statistically significant (p = 0.02). In the tear samples from PANDO/dacryolith patients, the mean ± SD total protein level was 129.0 ± 72.9 mg/dl. In the tear samples from the PANDO controls the mean ± SD total protein level was 261.6 ± 132.5 mg/dl. The difference between the two groups was statistically significant (p = 0.00). In the tear protein fractions from electrophoresis, a low level of lysozyme was observed in the PANDO/dacryolith samples compared with the PANDO control samples (p = 0.03). The tears from patients with PANDO due to dacryoliths showed a change in the concentrations of electrolytes and protein, particularly lysozyme, compared with that of the patients with PANDO without dacryoliths, which may be related to the pathogenesis of dacryoliths.


Journal of Pediatric Ophthalmology & Strabismus | 2001

Effect of Botulinum toxin A chemodenervation in sensory strabismus

Sueng Han Han; Helen Lew; Chang Woog Jeong; Jong Bok Lee

PURPOSE To study the effect of botulinum toxin type A chemodenervation in sensory strabismus. METHODS Twelve patients with sensory strabismus were treated with an injection of botulinum toxin type A (Botox; Allergan, Irvine, Calif). Botulinum toxin type A was diluted with 0.9% sodium chloride without preservative at a dose that ranged from 1.25-5 U. A Teflon-coated needle electrode was inserted into the medial rectus muscle in cases of esotropia and into the lateral rectus muscle in cases of exotropia. Four patients were treated with > or =2 injections of botulinum toxin type A. Changes in the angle of strabismus and related complications were followed for >6 months postinjection. RESULTS The mean deviation before injection was 33.8 prism diopters (delta) and the mean corrective effect on the deviation was 72.8% after injection in patients with sensory strabismus. The final deviation in 9 patients was <10 delta. Complications were hypertropia in 3 (25%) patients and conjunctival hemorrhage in 1 (8.3%) patient. CONCLUSION Botulinum toxin type A is likely to prevent muscle contracture and affect muscle and neuronal tissues. This study on the effects of sensory strabismus with botulinum toxin type A injection suggests it has the potential to replace surgery or be used as an adjuvant therapy.


Ophthalmic Plastic and Reconstructive Surgery | 2001

Acinic cell carcinoma of the lacrimal gland with intracranial extension: a case report.

Jaewoo Jang; Jeong H. Kie; Sang Y. Lee; Sung-Joo Kim; Helen Lew; Soon W. Hong; Thomas C. Spoor

Purpose To describe a patient with acinic cell carcinoma of the lacrimal gland presenting with atypical manifestations including erosion of the orbital roof and intracranial extension. We compare his clinical manifestations with two previously reported cases. Methods Case report. Results A 51-year-old man presented with a firm, tender, palpable mass in the superior temporal portion of his right orbit. CT scan demonstrated a large homogeneously enhancing mass displacing the globe inferiorly and eroding the roof of the orbit. MRI of the orbit showed intracranial extension of tumor. Biopsy revealed an acinic cell carcinoma of the lacrimal gland. Conclusions Acinic cell carcinoma is a rare neoplasm occurring primarily in the major and minor salivary glands.


Acta Ophthalmologica | 2012

Tear meniscus measurement in nasolacrimal duct obstruction patients with Fourier-domain optical coherence tomography: novel three-point capture method

Helen Lew; Sang Yeul Lee

Purpose:  Fourier‐domain optical coherence tomography (FD ODT) for the evaluation of marginal tear film has not been performed in patients with watery eye or in a controlled study. We used FD OCT to evaluate the height of the lower lid tear film at three points in normal adults and compared it with two watery eye groups.


Ophthalmic Research | 1999

The Effects of High-Dose Corticosteroid Therapy on Optic Nerve Head Blood Flow in Experimental Traumatic Optic Neuropathy

Helen Lew; Sang Yeul Lee; Jae Woo Jang; Hyeyoung Kim; Shin Jeong Kang; Sung Joo Kim

Purpose: The objective of this study was to ascertain the effect of high-dose steroid therapy in traumatic optic neuropathy using the Heidelberg retina flowmeter (HRF) to detect changes in optic nerve head blood flow. Methods: We experimentally damaged the optic nerves of 10 white rabbits with a Hartman mosquito clamp. The first group (n = 5) was treated with intravenous dexamethasone (0.25 mg/kg) every 6 h for a 48-hour period. The second group (n = 5) served as controls. Both groups were tested prior to operation, 1 week, 1 month and 2 months after surgery. Results: Experimental optic nerve damage caused a significant decrease in optic nerve head blood flow of 50.51% (p = 0.001), with a volume decrease of 46.02% (p = 0.001) and a velocity reduction of 43.12% (p = 0.002) compared to the baseline. After 2 months, in the group treated with high-dose corticosteroid therapy, optic nerve head blood flow was increased by 76.90% (p = 0.012), volume by 77.53% (p = 0.012) and velocity by 47.21% (p = 0.012) compared to the control group. Conclusion: The high-dose corticosteroid therapy improved the optic nerve head blood flow as demonstrated in experimental traumatic optic neuropathy. The HRF may be used to assess the therapeutic responses in traumatic optic neuropathy under variable conditions.


International Journal of Molecular Medicine | 2016

Human umbilical cord blood mononuclear cells and chorionic plate-derived mesenchymal stem cells promote axon survivalin a rat model of optic nerve crush injury

Sokjoong Chung; Seungsoo Rho; Gijin Kim; Sora Kim; Kwang-Hyun Baek; Myungseo Kang; Helen Lew

The use of mesenchymal stem cells (MSCs) in cell therapy in regenerative medicine has great potential, particularly in the treatment of nerve injury. Umbilical cord blood (UCB) reportedly contains stem cells, which have been widely used as a hematopoietic source and may have therapeutic potential for neurological impairment. Although ongoing research is dedicated to the management of traumatic optic nerve injury using various measures, novel therapeutic strategies based on the complex underlying mechanisms responsible for optic nerve injury, such as inflammation and/or ischemia, are required. In the present study, a rat model of optic nerve crush (ONC) injury was established in order to examine the effects of transplanting human chorionic plate-derived MSCs (CP-MSCs) isolated from the placenta, as well as human UCB mononuclear cells (CB-MNCs) on compressed rat optic nerves. Expression markers for inflammation, apoptosis, and optic nerve regeneration were analyzed, as well as the axon survival rate by direct counting. Increased axon survival rates were observed following the injection of CB-MNCs at at 1 week post-transplantation compared with the controls. The levels of growth-associated protein-43 (GAP-43) were increased after the injection of CB-MNCs or CP-MSCs compared with the controls, and the expression levels of hypoxia-inducible factor-1α (HIF-1α) were also significantly increased following the injection of CB-MNCs or CP-MSCs. ERM-like protein (ERMN) and SLIT-ROBO Rho GTPase activating protein 2 (SRGAP2) were found to be expressed in the optic nerves of the CP-MSC-injected rats with ONC injury. The findings of our study suggest that the administration of CB-MNCs or CP-MSCs may promote axon survival through systemic concomitant mechanisms involving GAP-43 and HIF-1α. Taken together, these findings provide further understanding of the mechanisms repsonsible for optic nerve injury and may aid in the development of novel cell-based therapeutic strategies with future applications in regenerative medicine, particularly in the management of optic nerve disorders.


Yonsei Medical Journal | 2005

Ocular Motility Disturbances in Orbital Wall Fracture Patients

Sang-Hun Lee; Helen Lew; Young Soo Yun

It is difficult to identify the exact cause of ocular motility disturbances in orbital wall fracture patients. By performing CT and ocular motility tests before and after surgery, this study analyzes the functions of the extraocular muscles and determines correlations between the results. Between February 2001 and January 2003, 45 eyes of 45 patients with orbital wall fractures, whose medical records could be traced back at least 6 months, underwent surgical repair in our hospital. All variables were analyzed using the independent t-test, paired t-test, and Chi-square test. There was no significant difference in the location and degree of fracture and the incarceration pattern of 6 patients who had moderate or severe diplopia, and of the remaining patients 6 months after surgery. However, in the case of diplopia, the sum of ocular motility limitation was 5.67 ± 4.18, and the degree of extraocular motility disturbance was 3.67 ± 2.42 before surgery. When there was no diplopia, the sum of ocular motility limitation was 1.13 ± 1.38, and the degree of extraocular motility disturbance was 1.08 ± 1.16 (p < 0.005, independent t-test). Ocular movement was successfully recovered by surgical reduction within 3 weeks from trauma. Postoperative ocular motility disturbance was more related to various ocular motility test results than CT findings. Ocular motility disturbances can remain after surgery if ocular motility limitation and extraocular motility disturbance are significant after trauma. Additional studies on the various tests to examine functions of extraocular muscles are required to identify and analyze the exact cause of ocular motility disturbance.

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Choun-Ki Joo

Catholic University of Korea

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