Download PDF (1940K)

ORIGINAL ARTICLES

THE POSSIBILITY OF THE APPLICATION OF LOW REACTIVE LEVEL LASER THERAPY IN THE FIELD OF OPHTHALMOLOGY

*Toshio Ohshiro M.D., Ph.D.1, Takafumi Ohshiro M.D.2, Katsumi Sasaki M.D.2, Shunji Fujii M.D.2, Yuki Taniguchi M.D.1 and Masaru Yoshida3, Kiyofumi Takenouchi1 and Mitsuaki Kohzuma1

1: Japan Medical Laser Laboratory, Tokyo, Japan 2: Ohshiro Clinic, Tokyo, Japan 3: Shinwa Excel Co., Ltd.

The authors have over 30 years experience of treatment with lasers, more than 25 of which have been with low reactive-level laser therapy. (LLLT) Based on our experience, we have continuously attempted to develop new treatments and broaden the clinical application of lasers. Many patients receiving LLLT for an entity other than sight problems have spontaneously described a sense of increased visual acuity following their treatment, and the present study was designed to see if there was in fact, any effect of LLLT on vision. Six healthy adult subjects aged 56~68 years old, were treated with LLLT according to the proximal priority theory (PPT). The subjects’ close range, far range visual acuity and astigmatism were examined prior to, one hour after and 24 hours after LLLT. The laser hardware used in this experiment was the OhLase HT2001 (Japan Medical Laser Laboratory, Tokyo, Japan) and the Screenoscope (Topcon, Tokyo, Japan). A high rate of improve- ment was seen for both close range and far range visual acuity but a particularly noteworthy improvement rate of 91.7% was seen at examination for far sightedness immediately after LLLT. LLLT in the field of ophthalmology is promising and further controlled studies carried out by oph- thalmologic specialists in larger patient groups may yield new indications for LLLT in this field.

Key Words: LLLT, Myopia, Presbyopia, Astigmatism

Introduction (9-10), alleviation of allergic symptoms (11-13)and female infertility (14-15). In the course of 30 years, the authors Laser treatment can be grouped into surgical laser have conducted many studies on LLLT including an treatment (HLLT) and non-surgical laser treatment experiment with Senbai Hospital demonstrating the (LLLT) according to the tissue response to lasers. The penetration depth of laser light using the Rand radi- Ohshiro clinic, in conjunction with Japan Medical Laser ographic phantom (16) and have also also demonstrat- Laboratory has developed new applications of laser ing increased cerebral blood flow following LLLT (17-18) treatment since 1975 mainly in the field of plastic using SPECT and Doppler ultrasound, hence proving surgery (1-5). Among the achievements of the 30 years that proximal priority treatment (19-20) is fast and effec- experience using lasers are the treatment of senile tive. flecks, rhytides and laser hair removal with HLLT, and Recently, the increased use of personal comput- a wide variety of indications for LLLT, ranging from ers and mobile phones has caused increased stress to pain attenuation (6-8), enhancement of wound healing the eyes. The authors have also noticed spontaneous comments from patients stating that their visual acuity Addressee for Correspondence: and/or ocular fatigue had improved after LLLT for an Toshio Ohshiro M.D., Ph.D. unconnected entity.. The authors therefore decided to Japan Medical Laser Laboratory Shinsei-kaikan Building 4F, 33-2 Shinanomachi, Shinjyuku- investigate how the increased cerebral blood flow ku Tokyo, JAPAN 160-0016 affects the eyes and vision. The investigation was con- Tel: +81-3-5269-1403 Fax: +81-3-5269-1410 Manuscript received: October 2007 E-mail: [email protected] Accepted for publication: November 2007 ©2007 JMLL, Tokyo, Japan Laser Tberapy 16.4: 189-197 189 ORIGINAL ARTICLES

Fig. 2: Chart for astigmatism examination

Fig. 3: Letter E chart for measurement of visual Fig. 1: Screenoscope (Topcon, Tokyo, acuity Japan)

ducted by measuring post-treatment changes of visual porarily and an attempt to read the next letter was acuity and astigmatism data following laser treatment made. Visual acuity was defined by the last letter read performed following the protocol listed hereafter. correctly on the chart. In order to control the luminance of the room Subjects and Methods where the measurements were being made and negate any effect of weather, all windows in the room were The subjects were 6 healthy adults (male:4, female:2) covered with lightproof curtains (Fig. 4). The 3 mm aged 56-68 years old (average age 61.7). Bilateral visu- thick lightproof curtain (Kawashima Selkon Textiles al acuity was measured for close range (0.3m) and far Co., Ltd.) consisted of three layers the middle layer of range (5 m) and also an examination for astigmatism which was silver and outside layers were blue. The was performed with the Screenoscope (Topcon) (Fig. only light source available in the room was a fluores- 1). Measurements were made before treatment, imme- cent light fixed to the ceiling. Luminance of the actual diately after treatment, one hour after treatment and experimental site was measured using an A-class illu- one day after treatment. minometer, the Iluminance Mater 510-01 (Yokokawa For the examination for astigmatism, the subjects M&C). The luminance was 0.4 lx in the room on a were shown an array of triple lines placed in a radiat- sunny day with the lights off, and was 1062 lx with the ing pattern and pointing in 7 different directions (Fig. lights on. 2). The subjects recorded the clarity of their vision on paper (Table 1) where clear vision was recorded as +, The laser device used for treatments was the and unclear as – , while ± was recorded for anything OhLase HT2001 (Japan Medical Laser Laboratory, in between. Tokyo, Japan) (Fig. 5). It is a GaAlAs diode laser emit- Visual acuity was measured using the E chart ting at a near infrared wavelength of 830 nm, deliver- (Fig. 3), where the subjects read the direction of the ing continuous wave energy with an incident power of opening of the E from the top of the chart,. Correct or 60 mW giving an incident irradiance (power density) incorrect answers were recorded on the chart (Table of approximately 2 W/cm2 (Table 2). 1) as ‘O’ or ‘X’, respectively. Any letter that was LLLT was performed according to the proximal answered incorrectly or was unclear was deferred tem- priority theory with the laser held against the neck and

190 Ohshiro T. ET AL. ORIGINAL ARTICLES

Table 1: Record chart

LLLT IN OPHTHALMOLOGY 191 ORIGINAL ARTICLES

Table 2: Specifications of OhLase HT2001

Product description Diode laser Product name OhLase HT2001 Chip GaAlAs semiconductor Wavelength 830 nm Output 60 mW Irradiation area 0.03 cm2 Irradiation mode Continuous wave

Fig. 4: Light proofing the room

Fig. 5: OhLase HT2001 semi-conductor laser

following the protocol listed below incorporating stretches with isometric maneuvers (Fig. 6). The irradi- ation time for each stretch or maneuver was 8 seconds, giving an incident radiant flux (energy density) for each of ≅ 16 J/cm2.

1. Lateral stretch of the neck and isometrics (rotation) Two sets of Clock wise rotation 8 secs. And Counter clock wise rotation 8 secs. 2. Shoulder shrug isometric maneuver, caudal and for- ward Caudal 8 secs. Forward 8 secs. 3. Isometric maneuver of the chest region Fig. 3: Letter E chart for measurement of visual acuity

192 Ohshiro T. ET AL. ORIGINAL ARTICLES

Table 3-1: Far range (5m) Result according to direction

Result for both eyes (number of cases) Result for both eyes (%) Results Direction 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Deficiency prior ro treatment 3 4 5 6 6 9 3 Deficiency corrected immediately after treatment 3 2 3 1 2 8 3 100% 50% 60% 17% 33% 89% 100% Correction seen immediately after treatment and lasted after one hour 1 1 1 1 1 4 1 33% 25% 20% 17% 17% 44% 33% Correction seen after one hour of treatment and lasted until the following day 0 0 1 1 1 2 1 0% 0% 20% 17% 17% 22% 33% Nochange immediately after treatment but correction seen after one hour 0 0 0 0 0 1 0 0% 0% 0% 0% 0% 11% 0% Nochange immediately after treatment but correction seen after one hour, and effect lasting until the following day 0 0 0 0 0 0 0 0% 0% 0% 0% 0% 0% 0% No change on the day of treatment but correction seen after one day 0 0 0 0 0 1 0 0% 0% 0% 0% 0% 11% 0%

Table 3-2: Near range (0.3m) Result according to direction

Result for both eyes (number of cases) Result for both eyes (%) Results Direction 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Deficiency prior ro treatment 6 10 10 11 11 11 6 Deficiency corrected immediately after treatment 2 3 1 2 3 4 2 33% 30% 10% 18% 27% 36% 33% Correction seen immediately after treatment and lasted after one hour 1 0 0 1 2 3 2 17% 0% 0% 9% 18% 27% 33% Correction seen after one hour of treatment and lasted until the following day 0 0 0 1 1 3 1 0% 0% 0% 9% 9% 27% 17% Nochange immediately after treatment but correction seen after one hour 0 0 0 1 0 0 0 0% 0% 0% 9% 0% 0% 0% Nochange immediately after treatment but correction seen after one hour, and effect lasting until the following day 0 0 0 0 0 0 0 0% 0% 0% 0% 0% 0% 0% No change on the day of treatment but correction seen after one day 0 1 0 0 1 0 0 0% 10% 0% 0% 9% 0% 0%

Table 4: Significant

Nearsighted R Nearsighted L A V G T.O M.Ko Y.O M.Ki E.A K.T T.O M.Ko Y.O M.Ki E.A K.T 1.2 0.6 0.8 0.8 0.6 0.8 1.2 1.0 0.5 0.7 0.6 0.7 0.79 1.5 0.9 0.8 0.9 0.6 0.8 1.2 1.0 0.6 0.7 0.8 0.8 0.88 1.5 0.9 0.8 0.9 0.6 0.8 1.2 1.0 0.5 0.9 0.6 0.9 0.88 1.5 0.6 0.8 0.9 0.6 0.8 1.2 1.0 0.6 1.0 0.6 0.9 0.88

Table 5: Significance

immediately after treatment one hour after one day after Pre-tx 0.019688618 0.026490486 0.034073373 Significance < 0.05 < 0.05 < 0.05

LLLT IN OPHTHALMOLOGY 193 ORIGINAL ARTICLES

Pushing medially with palm of hands pressed Of the subjects whose visual acuity improved, in 8 against each other in front of the sternum 8 eyes (66.7%) of 5 patients increased visual acuity was secs. seen one day after treatment (Tables 9-1, 9-2). Pushing medially with palm of hands pressed 3. Examination of astigmatism against each other at a level below the xiphoid process. 8 secs. For the examination of astigmatism, a chart showing an Hands pulling apart laterally with fingers inter- array of triple parallel lines radiating in 7 different locked in front of the sternum 8 secs. directions was used. If the subject could clearly distin- Hands placed below the level of the xiphoid guish between the 3 lines, he/she recorded a ‘—’, process. 8 secs. when not sure they recorded ‘±’, and when the lines 4. Stretch of the hip region (1 rotation) were undistinguishable they recorded ‘+’ on the chart Lower left 8 secs. Mid left 8 secs. Upper left 8 shown in Table 1. secs. Examinations at both close range and distant Lower right 8 secs. Mid right 8 secs. Upper right range were taken for the 7 directions x 6 (subjects) x 2 8 secs. (eyes)=84 directions. Pre-treatment measurement 5. Stretch of the neck (lateral movement) showed that 36 close range and 65 distant range direc- Two sets of: To the right 8 secs. To the left 8 secs. tions were indistinguishable and were recorded as ‘+’. Improvement was classed as when sets of lines Results. which were indistinguishable pretreatment became dis- tinguishable, i.e., rated from ‘+’ to ‘–’. Immediate post- therapy improvement was seen in 22 directions (56%) 1. Long range visual acuity (myopia) of distant range, and in 17 directions (26%) of close The results of the measurements for myopia are listed range measurements. Furthermore, in subjects where in Table 4. The average pre-treatment visual acuity no change was seen immediately after LLLT, improve- was 0.79. The average for immediately after treatment ments in 1 direction (3%) at distant range and 1 direc- was 0.88 and remained so for one hour and 24 hr after tion (2%) at close range were seen one hour after treatment. The pre- and post-treatment results were LLLT, and in 1 direction (3%) at distant range and 2 examined for significance which revealed a level of directions at close range 24 hr after treatment. confidence of 5% for all results and therefore was con- Therefore the total improvement seen after LLLT was sidered significant (Table 5). 24 directions at distant range (62%) and 20 directions When these data are analyzed independently, (31%) at close range. eyes which showed no change were 5 eyes (41.7%) The result according to direction is shown in from 5 subjects, eyes which showed improvement Table 3. The improvement rate for the horizontal rays were 7 eyes (58.7%) from 6 subjects and of this 7, 5 (1, 7) immediately after LLLT was 100% compared to eyes (41.7%) from 4 subjects showed lasting improved the improvement rate of 17% for the vertical array (4). for over one day. (Tables 6-1, 6-2) This trend of more improvement in the horizontal arrays compared to the vertical array was also seen in 2. Close range visual acuity (presbyopia) measurements for presbyopia. The results of close range visual acuity are listed in Table 7. The pre-treatment measurements showed an Discussion average of 0.29 whereas the results immediately after treatment averaged 0.43. Further increase was seen at In the examination for astigmatism, there was a gross one hour and 24 hr after treatment with an average difference in improvement between the myopia and visual acuity of 0.48. The pre- and post-treatment presbyopia measurements, where greater improvement results were examined for significance which gave a was seen in myopia measurements. No identifiable level of confidence for the result immediately after cause for the discrepancy has been found. A difference treatment of 1% and for 24 hr post-treatment of (Table in the improvement rate between the horizontal arrays 8). As for the individual results, in 11 eyes from the 6 and vertical array was also seen. Further consultation subjects (91.7%) improvement was seen both immedi- with ophthalmologic specialists on data collection on ately posttreatment, I hr and 24 hr post-treatment. this subject is warranted and we plan for future stud- There was only one eye from one patient that showed ies. no change over the course of pre- and post-treatment. From this study, we believe that the improvement

194 Ohshiro T. ET AL. ORIGINAL ARTICLES

Table 6-1: Significance (nearsighted R)

Table 6-2: Significance (nearsighted L)

Table 7: Significance

Nearsighted R Nearsighted L AVG T.O M.Ko Y.O M.Ki E.A K.T T.O M.Ko Y.O M.Ki E.A K.T Pre-ex 0.2 0.2 0.3 0.5 0.3 0.2 0.3 0 0.4 0.5 0.4 0.2 0.29 Immediately after treatment 0.5 0.4 0.4 0.7 0.3 0.2 0.4 0.4 0.5 0.7 0.4 0.3 0.43 One hour after 0.5 0.2 0.4 1.2 0.3 0.2 0.3 0.3 0.5 1.2 0.4 0.2 0.48 One day after 0.4 0.2 0.3 1.2 0.4 0.2 0.4 0.2 0.5 1.2 0.5 0.2 0.48

Table 8: Significance

immediately after treatment one hour after one day after Pre-tx 0.002244482 0.035856796 0.028295103 Significance < 0.01 < 0.05 < 0.05

LLLT IN OPHTHALMOLOGY 195 ORIGINAL ARTICLES

Table 9-1: Significance (farsighted R)

Table 9-2: Significance (farsighted L)

seen in myopia is in fact a result of improvement in estimation of the true effect of LLLT in this interesting the degree of astigmatism. We would like to elucidate and very popular field. Once a more efficient treatment this in further studies. As for presbyopia, an improve- is developed and more clinical experience is gained ment in 91.7% was seen and an increase in average we believe that the efficacy of LLLT will be seen to visual acuity of hg 0.18 was observed. We believe that increase concomitantly. the proximal priority treatment increases cerebral Present laser applications in the field of ophthal- blood flow and hence increase the motility of the cil- mology are mainly HLLT as in the use of argon lasers liary muscles and thereby enhances the focus of the for the treatment of cataracts and diabetic retinopathy, image. Greater improvement and longer lasting or for mainly eximer laser-based treatments such as improvement may be seen through further basic and LASIK. The use of lasers in this field has been limited clinical ophthalmologically-based LLLT research. due to safety issues of the eyes, but the proximal prior- This is the first time for the authors to study the ity treatment with LLLT bypasses the problem since the role of proximal priority treatment in the field of oph- laser was not irradiated toward the eyes at all in the thalmology. We have attempted to gather as much data present study, yet still had a significant effect. LLLT in as possible, but we feel our limited time and resources this field is new and is anticipated to yield promising and experience in this field may have led to an under- clinical applications and results in the future.

196 Ohshiro T. ET AL. ORIGINAL ARTICLES

References

1: Ohshiro T. (1977): Dermatologic Laser Treatment Therapy, 9:25~32 Successfully Completed in Japan. Laser + Elektro- 11: Sasaki K, Ohshiro T. (1989): Role of Low Reactive Optik, 3 (34):34~35 Level Laser Therapy (LLLT) in the Treatment of 2: Ohshiro T. (1994): High Reactive-Level Laser Acquired and Cicatrical Vitiligo. Laser Therapy, 1 Treatment (HLLT) and Low Reactive-Level laser (3) :141~146 Therapy (LLLT) in Dermatology. Photomedicine 12: Ohshiro T. (1998): Classification of laser applica- and Photobiology, 16:123~126 tions in low reactive-level therapy (LLLT). Laser 3: Ohshiro T, Fujii S, Ohshiro T. (2001): General Therapy, 10 (1):40~47 Principles and the Classification of Medical 13: Fujii S, Ohshiro T, Ohshiro T, Sasaki K, Taniguchi Application of Lasers. Lasers in Medicine Surgery Y. (2007): Application of diode pumped Nd:YAG and Dentistry, 21~32 laser for allergic rhinitis. Laser Therapy, 16 (1) 4: Ohshiro T. (2002): 27 years of laser treatment~ a :17~24 personal perspective. Laser Therapy, 12, CD-ROM 14: Ohshiro T, Fujii S, Sasaki K, et al. (2001): Laser issue. therapy as an adjunctive treatment for severe 5: Ohshiro T, Sasaki K, Yasuda S, Fujii S. (2003): female infertility - A Preliminary report. Laser Application of Combined Laser Treatment for Therapy, 11 (2) :96~102 Tattoo Removal. Lasers in Medicine Surgery and 15: Ohshiro T, Fujii S, Sasaki K, et al. (2001): Laser Dentistry, 549-567 application for female infertility. In: International 6: Calderhead G, Ohshiro T, Itoh E, Okada T, Kato Y. proceedings division (CD-ROM). 2001, MONDUZZI (1981): The Nd:YAG and GaAlAs lasers; A compre- EDITORE hensive analysis in pain therapy. Laser Tokyo’81, 16: Ohshiro T. (1996): A new graphic representation of 21:1 medical laser applications. Laser Therapy, 8 (3) 7: Ohshiro T, Toya S, Motegi M, Maeda T. (1994): :185~190 Clinical consideration in protocol design for a dou- 17: Maeda T, Ohshiro T. (1994): A computer simula- ble blind trial on pain attenuation by laser therapy. tion model for analysis of rise in skin temperature, Laser Therapy, 6 (2):101~106 following irradiation with the GaAlAs Diode laser. 8: Asagai Y, Imakiire A, Ohshiro T. (2002): Laser Therapy, 6 (2) :85~94 Thermographic study of low level laser therapy for 18: Asagai Y, Imakiire A, Ohshiro T. (2002): acute phase injury. Laser Therapy, 12, CD-ROM Thermographic effects of laser therapy in patients Issue. with cerebral palsy. Laser Therapy, 12 CDR 9: Kami T, Yoshimura Y, Nakajima T, Ohshiro T, 19: Kudoh Chiaki, Inomata K, Okajima K, Motegi M, Fujino T. (1985): Effects of Low-Power Diode Ohshiro T. (1988): Low level laser therapy pain Lasers on Flap Survival. Annals of Plastic Surgery, attenuation machanisms,1. Laser Therapy, pilot 14 (3) :278~283 issue:3-6 10: Sasaki K, Ohshiro T. (1997): Assessment in the rat 20: Ohshiro T: An introduction to LLLT, progress in model of the effects of 830 nm diode laser irradia- laser therapy. In (Ohshiro T, Calderhead R.G.) tion in a diachronic wound healing study. Laser John Wiley & Sons, Ltd. 1991, 36~47

LLLT IN OPHTHALMOLOGY 197