1.The Reproducibility of BEasurements of Macular Capillary Bood Flow by Scanning Laser Doppler Flowmetry.
Moon Jeoung CHOI ; Hyung Chan KIM ; Ha Kyoung KIM
Journal of the Korean Ophthalmological Society 1998;39(10):2360-2365
To apply retinal capillary blood flow measurements using Scanning laser Doppler Flowmetry(SLDF) to clinical use, they should be reproducible and no interpersonal difference in nomal subject. Furthermore, the method of measurements must be simple, standardized and show acceptable range of error. We studied 10 eyes of 10 healthy normal subjects. Each subject was scanned in 2 sessions which were separated by at least 2 hours. In each session, we obtained 5 scans and measured macular capillary blood flow in two elected areas from the scanning images. The coefficients of variation of volume, flow, and velocity at each area were ranged from 3.4 to 13.2% 1.4 to 16.9%, and 3.1 to 14.3%, respectively, The reproducibility of measurements was good at each corresponding areas in each subject. No statistically significant locational difference was observed(Kolmogorov-Smirnov test, p>0.05). The Spearman rank correlation coefficients(r) were volume 0.75, flow 0.71, and velocity 0.73. They showed relatively significant correlation between first and second sessions. But there were signigicant differences on interpersonal difference in all 3 parameters: volume, flow, and velocity(Kruskal-Wallis one way ANOVA test. p<0.05). The comparison of measurements between different persons was not meaningful.
Capillaries*
;
Humans
;
Laser-Doppler Flowmetry*
;
Retinaldehyde
2.Experimental Studies on the Lower Abdominal Flap of the Rabbit by using the Laser Doppler Flowmetry and PGE1.
Jeong Tae KIM ; Hee Dong SON ; Keun Cheol LEE ; Jung Min PARK ; Seok Kwun KIM
Journal of the Korean Society of Plastic and Reconstructive Surgeons 2001;28(5):552-557
The survival of flap has a vital importance in the reconstructive surgery. This study was designed to investigate the relation of the survival area and the variation of flow value measured by laser Doppler flowmetry and to elucidate the effect of PGE1 on flap survival with an objective index. Sixteen New Zealand White rabbits were divided into 3 groups (8 of control group, 4 of intravenous PGE1 group and 4 of topical PGE1 group). The lower abdominal island flap (10 x 5 cm) based on the superficial epigastric pedicle was elevated and reset again at the previous location. The flow values were checked and it was taken as the value of LD. LD ratio was obtained by calculating the ratio of LD value in each experimental period to that of the baseline data taken before flap elevation. Finally, the data of flap survival area on the 8th experimental day was collected by using the plannimetry method. The results: the survival areas of intravenous PGE1 group (72.0 +/- 22.3%) and topical PGE1 group (78.0 +/- 22.7%) showed a significant increase compared to that of control group (46.5 +/- 14.3%, p < 0.01). The flap survival has the close relationship of the LD ratio measured immediately after flap elevation. The neovascularization period for the survival is considered at least 6 days. In conclusion, these experimental results can show an evident relation between the survival area of the flap and the LD ratio value measured immediately after the flap elevation. The LD ratio value measured immediately after flap elevation has the great significance as a critical limit for expecting the fate of flap survival. Therefore this value will be used as one of the beneficial standards for expecting the prognosis of microsurgical reconstruction in clinical trials.
Alprostadil*
;
Laser-Doppler Flowmetry*
;
Prognosis
;
Rabbits
3.The Study on the Effect of Six Soaps on Cutaneous Irritation Measured by Noninvasive Technique.
Korean Journal of Dermatology 1996;34(1):116-121
BACKGROUND: Soaps are the most widely used body cleanser and sometimes cause irritation of the skin. OBJECTIVE: Our purpose was to compare the skin irritancy of 6 soaps using noninvasive techniques. METHODS: The skin responses to patch test with 6 soaps were measured by visual scoring, evaporimeter and corneometer. RESULTS: The results are summarized as follows. 1. F soap was shown to cause the least irritancy measured by visual scoring and corneometer. But using evaporimeter, there were no differences in irritancy between the 6 soaps. 2. Through correlation analysis, we found that the evaluation of the evaporimeter was closely related to visual measurement. CONCLUSION: Soap irritancy can be measured by noninvasive techniques, such as the evaporimeter, corneometer, laser doppler flowmetry and visual scoring. Further study of evaluation after short and repeat contacts with soap are needed.
Laser-Doppler Flowmetry
;
Patch Tests
;
Skin
;
Soaps*
4.Liquid flow field measurement in a tube with a combination of stenosis and bifurcation.
Chaojie ZHANG ; Mingyuan ZHANG ; Xianran ZHU ; Jian YANG
Journal of Biomedical Engineering 2006;23(5):944-946
Two-D liquid velocity field in a tube with a combination of a stenosis and a bifurcation was measured with refractive index matching technique using Laser Doppler Velocimeter (LDV). The flow ratio of main tube to bypass was 1:4. It is found that the axial velocity profile has two peaks in the XOY plane which is skewed to the main tube wall facing the flow from the bypass, and it manifests itself in the form of "M" in the XOZ plane. A two counter-rotating vortices in the main tube cross section downstream the conjunction region is also detected.
Laser-Doppler Flowmetry
;
instrumentation
;
methods
;
Rheology
5.21 Cases of the Regional Cerebral Blood Flow During Craniotomy.
Young Do CHO ; Byung Il CHO ; Sang Geun CAHNG
Journal of Korean Neurosurgical Society 1994;23(3):290-294
A new technique, the laser-doppler flowmetry. has been used intraoperatively to measure blood flow responses in the normal brain tissue, the traumatic brain tissue and so on. The flow estimate by this technique is based on the assessment of the doppler shift of the low power laser light, which is scattered by moving red blood cells.
Brain
;
Craniotomy*
;
Doppler Effect
;
Erythrocytes
;
Homeostasis
;
Laser-Doppler Flowmetry
6.A Case of Arteriovenous Fistula Associated with Macrotia.
Sang Hyun CHO ; Jong Yuk YI ; Baik Kee CHO ; Won HOUH
Korean Journal of Dermatology 1989;27(4):444-447
We report a case of arteriovenous fistula involving the external ear in a 27- year-old male patient, who presented with pruritic erythematous scaly patch with multiple pulsating nodules on the thickened and hypertrophied left auricle.The blood flow, measured by laser Doppler velocimetry, was increased markedly on the affected site comparing with the other (710.33mV vs 8.4mV, 663.33mV vs 107. 33mV). We suggest that macrotia must be considered as the one of the clinical manifestations of cutaneous arteriovenous fistula.
Arteriovenous Fistula*
;
Ear, External
;
Humans
;
Laser-Doppler Flowmetry
;
Male
7.Influence of Ultrasound on the Percutaneous Absorption of Methyl Nicotinate.
Sung Joo HWANG ; Sang Lip CHUNG ; Do Won KIM ; Jae Bok JUN
Korean Journal of Dermatology 1997;35(5):947-955
BACKGROUND: The mechanism of enhancing effect of ultrasound on the percutaneous absorption of a drug is unclear. But thermal, chemical and mechanical effects are assumed to play a role in enhancing transdermal drug delivery. OBJECTIVE: The aim of this study was to determine if ultrasound enhances percutaneous absorption of methyl nicotinate(MN) without raising the skins surface temperature. METHODS: Treatment consisted of the application of ultrasound massage(1.0 MHz, 1.0 watt/cm2, continuous output) or placebo massage(0 MHz) for 3 min to the forearms of the volunteers, followed by a standardized application of MN at intervals of 15 sec and 10 min postmassage. Percutaneous absorption of MN was monitored using laser doppler flowmetry. RESULTS: 1. Data from the ultrasound treated sites after 15 sec showed significant decrease(p<0.05, paired t-test) in the T(0)(time between MN application and its initial response), T(MAX)(time between MN application and maximuvi response) and increase in the LDF(MAX) .(maximum cutaneous blood flow) compared to those of the control sites. 2. Data from the ultrasound treated sites after 10 min showed no difference in the T(0) and T(MAX) but significant increase in the LDF(MAX) compared to those of the control sites. 3. Data from ultrasound trvated sites both after 15 sec and 10 min showed significant increase in basal cutaneous blood flow(LDF(DH2O)) compared to those of the control sites. 4. There was no difference between the ultrasound treated sites and the control sites in the skins surface temper ature. CONCLUSION: The results of this study suggest that ultrasound may affect the skin structure to provide skin penetration enharcement even without raising the skins surface temperature.
Forearm
;
Laser-Doppler Flowmetry
;
Niacin*
;
Skin
;
Skin Absorption*
;
Ultrasonography*
;
Volunteers
8.Estimation of Lower Abdominal Flap Survival in Rabbit Model Using Laser Doppler Flowmetry Value.
Byung Hoon CHA ; Seok Kwun KIM ; Jeong Tae KIM
Journal of the Korean Society of Plastic and Reconstructive Surgeons 2002;29(4):311-317
Microsurgery has developed over the last three decades to become a routine surgical operation and it's indications for autogenous tissue transplant have been increased. Despite of initial success rate ranging from 80 to 95 percent, the compromise of vascular pedicle causing flap loss has been still one of the serious complications in the microsurgery. As the success of re-exploration is inversely proportional to the time elapsed till the clinical recognition of vascular complication after operation, early detection of perfusion compromise is an important determinant of flap salvage. In this sense, the laser doppler flowmetry has been widely used as an objective monitoring system for the flap survival. This study was designed to investigate the critical time point of flap survival and to estimate the variation of flow value measured by laser doppler flowmetry. Sixteen New Zealand white rabbits weighed from 1.5 kg to 2 kg were used. The lower abdominal island flap(10 5 cm) based on the superficial epigastric pedicle was elevated and repositioned again. The flow values were checked before the flap elevation, immediately after the flap elevation. And thereafter, they were also checked before and after the ligation of pedicle at the 6th, 8th, 10th, 12th, 14th and 16th day of experimental period. After a preliminary study, additional 5 rabbits on each 14th and 16th experimental day were included in the same experimental procedure. The LD value in each point was measured with the laser doppler flowmetry and it was taken as the value of LD at the experimental time. After that, LD ratio(D/C) was obtained by calculating the ratio of LD value(D) after pedicle ligation to that(C) before pedicle ligation in each experimental period. The flap necrosis was noted from the 6th postoperative day to the 12th postoperative day after the pedicle ligation. On the 14th day after the operation, flap survival was noticed after the pedicle ligation. In the group of flap necrosis, LD ratio(D/C) from the 6th day to the 12th postoperativ
Laser-Doppler Flowmetry*
;
Ligation
;
Microsurgery
;
Necrosis
;
Perfusion
;
Rabbits
;
Transplants
9.Analysis of Foveal Hemodynamics between Normal and Stage I Macular Hole with Scanning Laser Doppler Flowmetry (HRF:Heidelberg Retinal Flowmetry).
Hyung Keun LEE ; Hyoung Jun KOH ; Soon Hyun KIM ; Oh Woong KWON
Journal of the Korean Ophthalmological Society 1998;39(7):1446-1452
The exact pathophysiology of stage I macular hole has been unknown. But several factors have been found that have a potentials to develop and progress of macular hole. The hemodynamic changes on macular hole was one of them and the purpose of this study was to evaluate the hemodynamic differences between the normal and the stage I macular hole. Blood volume, flow and velocity on fovea and parafoveal area were measured with Heidelberg Retinal Flowmetry(HRF, Heidelberg Engineering, W. Germany). After the evaluation, the blood flow was significantly decreased on the foea in Stage I macular hole patients (P<0.001). These findings suggest that stage I macular hole maybe induced by decreased flood flow. And HRF has a potential for a new measuring modality of hemodynamics for mcular disease suggest.
Blood Volume
;
Hemodynamics*
;
Humans
;
Laser-Doppler Flowmetry*
;
Retinal Perforations*
;
Retinaldehyde*
10.The Application of Laser Doppler Flowmetry for Allergic Rhinitis and Rhinitis Medicamentosa.
Jeung Gweon LEE ; Joo Heon YOON ; Hyun Jun KIM ; In Suk MOON ; Jae Yol LIM ; Jong Bum YOO
Journal of Rhinology 2002;9(1, 2):30-34
BACKGROUND AND OBJECTIVES: Allergic rhinitis (AR) and rhinitis medicamentosa (RM) have different mucosal color and pathophysiology. To investigate whether the mucosal color and nasal blood flow are different between the diseases in spite of same symptoms, we designed this study. Materials and Methods: 20 patients with allergic rhinitis and 21 patients with rhinitis medicamentosa were compared with 20 normal volunteers using mucosal color grading and Laser Doppler flowmetry. The Laser Doppler flowmetry was performed with a Periflux 4001 (Perimed, Jrtlla, Sweden) and perfusion unit (PU), velocity unit (VU), and concentration Unit (CU) were measured. The Laser Doppler flowmetry data in AR and RM were compared with those of the normal subjects, and between AR and RM. RESULTS: The perfusion score of AR and RM were lower than the control (p<0.05) and it was statistically significant that the mucosal color of AR were pale and of RM were reddish, comparing to the control group (p<0.05). CONCLUSION: The nasal blood flow was decreased with AR and RM compared to control but the mucosal color of AR and RM were different because of the difference of pathophysiology of diseases. When diagnosing RM, observation of mucosal color and measurement of nasal blood flow will be helpful besides the history of long-term use of nasal decongestant.
Healthy Volunteers
;
Humans
;
Laser-Doppler Flowmetry*
;
Perfusion
;
Rhinitis*