1.Fast photoacoustic imaging systems using pulsed laser diodes: a review.
Paul Kumar UPPUTURI ; Manojit PRAMANIK
Biomedical Engineering Letters 2018;8(2):167-181
Photoacoustic imaging (PAI) is a newly emerging imaging modality for preclinical and clinical applications. The conventional PAI systems use Q-switched Nd:YAG/OPO (Optical Parametric Oscillator) nanosecond lasers as excitation sources. Such lasers are expensive, bulky, and imaging speed is limited because of low pulse repetition rate. In recent years, the semiconductor laser technology has advanced to generate high-repetitions rate near-infrared pulsed lasers diodes (PLDs) which are reliable, less-expensive, hand-held, and light-weight, about 200 g. In this article, we review the development and demonstration of PLD based PAI systems for preclinical and clinical applications reported in recent years.
Lasers, Semiconductor
2.An Effects of Contact Transscleral Diode Laser Cyclophotocoagulation in Glaucoma Patients.
Seung Jin HONG ; Hee Bae AHN ; Dong Won LEE ; Sae Heun RHO
Journal of the Korean Ophthalmological Society 1997;38(4):659-665
We observed the changes of IOP after contact transscleral cyclophotocoagualtion with Diode laser which emit 810mm beam and we tride to investigatethe suitable level and range of energy when Diode laser was applied to the refractory glaucoma patients. Fifteen eyes underwent contact transscleral cyclophotocoagulation with energy 3J(Group A, 6eyes), 4J(Group B, 9eyes) separately and intraocular pressure(IOP) was measured at 1 day, 1 week, 1 month, 2 month, 3 month, 4month, 5month, 6month, postoperatively. The intraocular pressure(IOP) decreasing rate was 83.02% in A group and 64.72% in B group. The success rate was 50% in A group and 66.7% in B group at 6 month postoperatively. It is suggested that contact transscleral cyclophotocoagulation with Diode laser si useful in lowering IOP in refractory glaucoma patients.
Glaucoma*
;
Humans
;
Lasers, Semiconductor*
3.Effect of Transscleral Diode Laser Photocoagulation Applied Through Silicone Scleral Exoplants.
Journal of the Korean Ophthalmological Society 1999;40(5):1281-1287
Authors performed transscleral diode laser retinopexy through the conjunctiva, muscle and silicone scleral exoplant to evaluate its safety and efficacy in experimental rabbit eyes. Transscleral applications required energies of average 325. 2 mWwith duration of 0.5 second. The mean power required to produce comparable lesions through the conjunctiva, muscle and the buckle(MIRA #276)was 27%, 20%, and 33%higher, respectively. These results demonstrate that the diode laser photocoagulation applied through a scleral buckle is capable to produce chorioretinal scars without damaging the scleral tissue nor the buckling elements employed.
Cicatrix
;
Conjunctiva
;
Lasers, Semiconductor*
;
Light Coagulation*
;
Silicones*
4.Clinical application of helium-neon laser & diode laser for acceleration of wound healing.
Dong Ha HWANG ; Dong Gil HAN ; Ki Young AHN ; Dae Hwan PARK
Journal of the Korean Society of Plastic and Reconstructive Surgeons 1993;20(6):1216-1223
No abstract available.
Acceleration*
;
Lasers, Semiconductor*
;
Wound Healing*
;
Wounds and Injuries*
5.An Effects of Contact Transscleral Diode Laser Cyclophotocoagulation in Refractory Glaucoma Patients.
Ki Young KIM ; Jin Seok OH ; Kyung Wha LEE
Journal of the Korean Ophthalmological Society 1999;40(12):3407-3413
We evaluated the the effect and the suitable level of ciliary ablation with diode laser contact transscleral cyclophotocoagulation[TSCPC] in eyes with refractory glaucoma. Fourteen eyes were treated with contact transscleral cyclophotocoagulation on 180 degree[Group 1, 6 eyes], and 270 degree[Group 2, 8 eyes], and the intraocular pressure was measured at 1 day, 1 week, 1 month, 3 month, postoperatively. The mean preoperative intraocular pressure was 46.8+/-14.3 mmHg and the mean intraocular pressure at last examination was 29.5+/-13.2 mmHg. Success rate was defined as follows:[1] more than 20% intraocular pressure reduction from baseline, [2] less than 21 mmHg at final examination. Based on the definition of success 1, the success rate was 66.6% in group 1 and 87.5% in group 2. Based on the definition of success 2, the success rate was 50% in both group. It suggests that contact transscleral cyclophotocoagulation with diode laser is useful in lowering IOP in refractory glaucoma patients and the treatment is also effective with ablation of 180 degree area in refractory glaucoma patients.
Glaucoma*
;
Humans
;
Intraocular Pressure
;
Lasers, Semiconductor*
6.Restoration of Volume after Partial Resection of Tongue in Rabbit: Comparative Analysis according to Scalpel, Electrocautery and Diode Laser with or without Closure.
Yang Hyo YOON ; Hyeong Jun JANG ; Soo Keun KONG ; Hyun Min PARK ; Byung Joo LEE ; Hwan Jung ROH ; Eui Kyung GOH ; Kyong Myong CHON ; Soo Geun WANG
Korean Journal of Otolaryngology - Head and Neck Surgery 2002;45(9):889-896
BACKGROUND AND OBJECTIVES: Performing oncologically safe, wide surgical excisions and postoperative volumetric restoration of resected tongues to gain functional recovery are contrary problems to deal with in performing glossectomy. There is no report about the volumetric restoration of a resected tongue according to resecting devices until now. The purpose of this study is to clarify the difference of postoperative volumetric changes of a resected tongue using a scalpel, electrocautery and laser with or without closure. MATERIALS AND METHOD: We used 12 rabbits for each group according to the resecting devices and also equally divided each group according to the closure or non-closure method. The volumetric changes of a resected tongue were measured by the Archimedes principles in one, two, three, and six months postoperatively. RESULTS: Regardless of resecting devices, the postoperative volume of a resected tongue was gradually increased as elapsed time. The nonclosure method was better than the closure method with respect to the volumetric restoration of the resected tongue regardless of the resecting devices, but there was no statistical significance of volumetric restoration between the closure and nonclosure methods in each group (p>0.05). The superior resecting device for the volumetric restoration of a resected tongue was diode laser, especially compared to electrocautry, in both closure and nonclosure method (p<0.05). CONCLUSION: The volumetric restoration after resection of the tongue using laser and nonclosure method are superior to electrocautery and to the closure method, respectively.
Electrocoagulation*
;
Glossectomy
;
Lasers, Semiconductor*
;
Rabbits
;
Tongue*
7.Sodium Fluoride Varnish in Management of Dentin Hypersensitivity Associated with Gingival Recession
Benju Shrestha ; Shaili Pradhan ; Krishna Prasad Lamichhane
Archives of Orofacial Sciences 2022;17(SUPP 1):97-106
ABSTRACT
Using laser for treatment of dentin hypersensitivity (DH) have recently shown promising results
and better immediate reduction in pain scores. However, its efficacy and mechanism of action is
controversial. Thus, this study aimed to evaluate the effectiveness of diode laser compared with
sodium fluoride varnish in treating DH in patients with gingival recession. Eighteen patients with
Miller’s class I and class II gingival recession and hypersensitivity in at least two non-adjacent
teeth were included in the study. Test surfaces (n = 25) were treated with diode laser, whilst control
surfaces (n = 23) were treated with 5% sodium fluoride varnish. Visual Analogue Scale (VAS) scores
were recorded for air and tactile stimulus for both groups at baseline, 15 min, 1 month and 3 months
post-treatment. Results showed significant (p < 0.05) reduction in VAS scores at 15 min, 1 month
and 3 months compared with baseline in both test and control surfaces, with no significant intergroup
differences. However, the percentage reduction in DH was more in laser at all evaluation periods.
The use of diode laser and sodium fluoride varnish showed good immediate and prolonged results.
Further studies are needed to come up with more effective treatment methods.
Lasers, Semiconductor
;
Dentin Sensitivity
;
Gingival Recession
8.Interstitial Laser Photocoagulation with Diode Laser Unit in Bovine Liver.
Hyo Jin PARK ; Hyung Jin SHIM ; Eun Jin SA ; Hyeon Joo KIM ; Kang Hyuk LEE ; Song Jun YANG ; In Sup SONG ; Yang Soo KIM ; Byung Kuk GWAK
Journal of the Korean Radiological Society 1999;40(1):39-45
PURPOSE: To evaluate the extent of tissue coagulation during interstitial laser photocoagulation (ILP) innormal bovine liver, using a diode laser unit and various parameters, and to determine whether the procedure isapplicable to clinical practice.. MATERIALS AND METHODS: Using an 18-gauge needle, experimental interstitiallaser photocoagulation (ILP) was carried out in normal bovine liver. On the basis of differing parameters, threegroups were established. For group I, a single photofiber with laser power of 1, 3 and 5 watts and an exposuretime of 60, 180, 300, 420 or 600 seconds was used. For groups II and III, four needles were fixed at a distance of1cm and 1.5cm ; in each case a needle fixation device was used, as well as a laser distributor for simultaneouslaser exposure of photofibers. As a control, four photofibers were placed as for groupIII, but to compare groups IIand III, each photofiber was exposed to a laser of 3 watts 300 seconds, without using a laser distributor. Toevaluate the range of tissue coagulation, specimens were analyzed both with regard to cross-sectional grossfindings and histopathologically . RESULTS: The largest diameter of thermal coagulation necrosis in Group I was15x15mm, and this was ball-shaped. Coalescence of coagulation between each photofiber was observed in Group II,and this was up to 25 mm in diameter. In Group III and controls, coalescence was not found, though the extent oftissue coagulation increased with increasing wattage and exposure time. The extent of charring at the center ofcoagulation also increased with increasing wattage. Smoke bubbles emanating from the coagulation area wereobserved, and during ILP involving a single photofiber, increased from 3 watts, applied for 300 seconds.CONCLUSION: Using an 8-gauge needle and a diode laser ILP, we have shown that a range of tissue coagulationacutely ablates normal bovine liver. In selective cases, the procedure could be applied to clinical trials.
Animals
;
Lasers, Semiconductor*
;
Light Coagulation*
;
Liver*
;
Necrosis
;
Needles
;
Smoke
;
Trout
9.Efficacy and Safety of Hair Removal with a Long-Pulsed Diode Laser Depending on the Spot Size: A Randomized, Evaluators-Blinded, Left-Right Study.
Seong Jin JO ; Jin Yong KIM ; Juhee BAN ; Youngjoo LEE ; Ohsang KWON ; Wooseok KOH
Annals of Dermatology 2015;27(5):517-522
BACKGROUND: The efficacy of the long-pulsed diode laser (LPDL) in hair removal is determined with various physical parameters. Recently, LPDLs with a larger spot size are commercially available; however, the independent effect of spot size on hair removal has not been studied. OBJECTIVE: This study aimed to compare the efficacy of the LPDL in hair removal depending on the spot size. METHODS: A randomized, evaluators-blind, intrapatient comparison (left vs. right) trial was designed. Ten healthy Korean women received three hair removal treatment sessions on both armpits with the 805-nm LPDL and followed for 3 months. A 10x10 mm handpiece (D1) or a 10x30 mm handpiece (D3) was randomly assigned to the right or left axilla. The fluence, pulse duration, and epidermal cooling temperature were identical for both armpits. Hair clearance was quantified with high-resolution photos taken at each visit. Postprocedural pain was quantified on a visual analogue scale. Adverse events were evaluated by physical examination and the patients' self-report. RESULTS: The mean hair clearance at 3 months after three treatment sessions was 38.7% and 50.1% on the armpits treated with D1 and D3, respectively (p=0.028). Procedural pain was significantly greater in the side treated with D3 (p=0.009). Serious adverse events were not observed. CONCLUSION: Given that the pulse duration, fluence, and epidermal cooling were identical, the 805-nm LPDL at the three times larger spot size showed an efficacy improvement of 29.5% in axillary hair removal without serious adverse events.
Axilla
;
Female
;
Hair Removal*
;
Hair*
;
Humans
;
Lasers, Semiconductor*
;
Physical Examination
10.Efficacy and Safety of Hair Removal with a Long-Pulsed Diode Laser Depending on the Spot Size: A Randomized, Evaluators-Blinded, Left-Right Study.
Seong Jin JO ; Jin Yong KIM ; Juhee BAN ; Youngjoo LEE ; Ohsang KWON ; Wooseok KOH
Annals of Dermatology 2015;27(5):517-522
BACKGROUND: The efficacy of the long-pulsed diode laser (LPDL) in hair removal is determined with various physical parameters. Recently, LPDLs with a larger spot size are commercially available; however, the independent effect of spot size on hair removal has not been studied. OBJECTIVE: This study aimed to compare the efficacy of the LPDL in hair removal depending on the spot size. METHODS: A randomized, evaluators-blind, intrapatient comparison (left vs. right) trial was designed. Ten healthy Korean women received three hair removal treatment sessions on both armpits with the 805-nm LPDL and followed for 3 months. A 10x10 mm handpiece (D1) or a 10x30 mm handpiece (D3) was randomly assigned to the right or left axilla. The fluence, pulse duration, and epidermal cooling temperature were identical for both armpits. Hair clearance was quantified with high-resolution photos taken at each visit. Postprocedural pain was quantified on a visual analogue scale. Adverse events were evaluated by physical examination and the patients' self-report. RESULTS: The mean hair clearance at 3 months after three treatment sessions was 38.7% and 50.1% on the armpits treated with D1 and D3, respectively (p=0.028). Procedural pain was significantly greater in the side treated with D3 (p=0.009). Serious adverse events were not observed. CONCLUSION: Given that the pulse duration, fluence, and epidermal cooling were identical, the 805-nm LPDL at the three times larger spot size showed an efficacy improvement of 29.5% in axillary hair removal without serious adverse events.
Axilla
;
Female
;
Hair Removal*
;
Hair*
;
Humans
;
Lasers, Semiconductor*
;
Physical Examination