ADVANCES IN LASEROLOGY ‐ SELECTED PAPERS OF LASER FLORENCE 2010: The 50th Birthday of Laser Medicine World
1364(2011); http://dx.doi.org/10.1063/1.3626906View Description Hide Description
1364(2011); http://dx.doi.org/10.1063/1.3626907View Description Hide Description
3‐[2‐(dimethylamino)ethyl]‐6‐nitroquinazolin‐4(3H)‐one, labeled BG1188, is a new synthesized compound, out of a series of quinazoline derivatives developed to fight the multidrug resistance of antibiotics acquired by bacteria. A characterization of the BG1188 powder was made using FTIR spectra in order to evidence the functional groups in the medicine’s molecule. The ultraviolet‐visible (UV‐Vis) absorption spectra were used to study the stability of the BG1188 solutions in two solvents and at different temperatures. BG1188 concentration in ultrapure water was varied between (stock solution) and The concentration recommended by higher activity on bacteria was For the same reason, this was the utilized concentration of BG1188 in dimethyl sulfoxide (DMSO). Time stability was characterized by comparing the time evolution of the UV‐Vis absorption spectra of the BG1188 solutions in ultrapure de‐ionized water or in DMSO. The spectra were recorded daily for about 4 months after the preparation for the BG1188 solutions in ultrapure water. Generally, samples are stable within the experimental errors at concentrations higher than but the stability time interval may vary from 119 days at to 34 days at Time evolution of the absorption spectra at in ultrapure water shows reproducibility within the measuring errors for time intervals up to 1032 hours (more than 40 days) after preparation. On the other hand, BG1188 solutions in DMSO may be considered unstable because the absorption spectra modify in terms of peak shapes and intensities, indicating that the samples exhibit modifications immediately after preparation. Regardless the solvent used, some aggregation phenomena took place and wire‐like aggregates were observed in all the solutions with the naked eye. These aggregates were analyzed, tentatively, using optical microscopy and FTIR.
Influence of Two Different Fluences on Laser Photobiomodulation of Wound Healing in Diabetic and Nondiabetic Mice1364(2011); http://dx.doi.org/10.1063/1.3626908View Description Hide Description
Background: Laser irradiation of wounds in mice and rats was shown in previous studies to stimulate healing but in almost all the studies the wounds were not covered.
Purpose: To compare the healing of covered wounds in diabetic and nondiabetic mice and the effect of laser irradiation 660 nm at two different fluences (energy densities).
Method: A single wound 5‐mm diameter was made on the left flank of forty‐seven diabetic and twenty nondiabetic mice and covered with Tegaderm HP dressing (day 1). Wounds were irradiated 660 nm 20 s using a low power (18 mW) or high power (80 mW) laser starting immediately post‐wounding for 7 consecutive days, with non‐irradiated wounds as controls. Mice were euthanized on day 8, 10 or 14. Wound specimens were cut and stained with haematoxylin and eosin, and examined by light microscopy.
Results: Wound healing was impaired in diabetic mice. Tegaderm HP dressing had retarded contraction in a large proportion of diabetic mice (splinted the wounds) and to a lesser extent in nondiabetic mice. Healing of splinted wounds was delayed compared to unsplinted wounds, but laser irradiation at high power stimulated healing by re‐epithelization and granulation tissue formation. The fluence of low power laser was estimated to be about while that of the high power laser was 3.7 to
Conclusion: Laser irradiation of wounds 660 nm with had little effect on healing of wounds in diabetic and nondiabetic mice, whereas irradiation with 3.7 to stimulated healing of wounds in diabetic mice most of which were splinted by the dressing.
1364(2011); http://dx.doi.org/10.1063/1.3626909View Description Hide Description
The use of Raman spectroscopy to analyze biopsy biochemistry and hence distinguish between the breast cancer stages was investigated. The biopsy samples were obtained from 13 patients who were clinically diagnosed with breast cancer. A preliminary diagnosis of some breast cancer patient was realized by pathologist of the Cancer Institute. The biopsies were put under the microscope and several points were chosen for Raman measurement. All spectra were collected at a Jobin‐Yvon LabRAM HR800 Raman Spectrometer with a NIR 830 nm laser. It is shown that the breast cancer stages of biopsies can be discriminated when the Principal Components Analysis (PCA) is applied to their Raman spectra. Ratios of some band intensities were analyzed and corresponded to proteins, phospholipids, and polysaccharides. The preliminary results suggest that Raman spectroscopy could be an excellent technique for stage determination of breast cancer.
Effects of LED Phototherapy on Bone Defects Grafted with MTA in a Rodent Model: A Description of the Bone Repair by Light Microscopy1364(2011); http://dx.doi.org/10.1063/1.3626910View Description Hide Description
We carried out a histological analysis on bone defects grafted (MTA) treated or not with LED, BMPs and GBR. Benefits of the isolated or combined use these techniques on bone repair have been suggested, but there is no report on their association with LED light. 36 rats were divided into 4 groups each subdivided into 3. Defects on G II and I were filled with the blood clot. G II was further irradiated with LED. G III‐IV were filled with gel; G IV was further irradiated. LED was applied over the defect at 48 h intervals and repeated for 15 days. Specimens were processed, cut and stained with H&E and Sirius red and underwent histological analysis. The results showed that MTA, due to its characteristics seemed not being directly affected by the LED light. But, the use of LED positively affect bone repair similarly to what was observed on different studies by our team using other biomaterials and laser. It is concluded that MTA seems not be directed affected by the LED light due to it characteristics. However, the beneficial results reported with its usage might be improved by the use of LED PT.
Morpho‐Structural Effects Caused by 660 nm Laser Diode in Epimastigotes Forms of Trypanosoma cruzi: In Vitro Study1364(2011); http://dx.doi.org/10.1063/1.3626911View Description Hide Description
Parasitic diseases represent a major public health problems in Latin America, in particular, Chagas disease or American trypanosomiasis, caused by the protozoan parasite Trypanosoma cruzi, infects more than 18 million people in all countries of Latin America. Visible light induces a photochemical reaction, that induces the activation of enzymes used mainly in the respiratory chain, and that light has the primary targets lysosomes and mitochondria of cells, increasing, the mitochondrial ATP production. The purpose of this study was to assess the morpho‐structural generated in the epimastigote form of Trypanosoma cruzi, after irradiation with a semiconductor laser InGaAlP, at a wavelength (λ) equal to 40 mW optical Power, emitting red light in the visible spectrum, with a dose of in continuous mode. Then the parasites that have undergone irradiation were analyzed by optical microscopy and compared to untreated. It found the increase in size of the kinetoplast (structure with high concentration of extracellular DNA‐kDNA, whose main function is to encode the respiratory chain enzymes such as ATPase and citocromoxidase), the cell nucleus and the cell volume of the parasite, leaving the more rounded.
Evaluation of Photodynamic Antimicrobial Therapy (PACT) against Trypomastigotes of Trypanosoma cruzi: In Vitro Study1364(2011); http://dx.doi.org/10.1063/1.3626912View Description Hide Description
Policies to combat Chagas disease presents a considerable degree of negligence and is classified at level III by TDR, where the focus of research is based on the improvement and wider dissemination of existing tools and strategies for combating them. The PACT is based on topical or systemic administration of a nontoxic dye sensitive to light, followed by low dose irradiation with visible light of wavelength appropriate. In the presence of oxygen found in the cells, the photosensitizer (FS) enabled may react with molecules in its vicinity by electron transfer or hydrogen, leading to production of free radicals (type I reaction) or by energy transfer to oxygen (type II reaction), leading to production of singlet oxygen. Both paths can lead to cell death and the destruction of diseased tissue. In this work, we verify the effectiveness of PACT associated with a semiconductor laser InGaAlP, a wavelength (λ) equal to 30 mW optical power, emitting red light in the visible spectrum, with a dose of in continuous mode, using methylene blue in five differents concentrations on the infective trypomastigote forms of Trypanosoma cruzi. To determine the viability of the parasites, one sample from each treatment group at each concentration was removed and analyzed in a hemocytometer, observing the decrease in the number of live parasites for the solution without treatment. The results demonstrated significant percentage of parasite lysis (up to 86% lethality), what can not be observed in the groups treated with laser or with the FS.
Bone Repair on Fractures Treated with Osteosynthesis, ir Laser, Bone Graft and Guided Bone Regeneration: Histomorfometric Study1364(2011); http://dx.doi.org/10.1063/1.3626913View Description Hide Description
The aim of this study was to evaluate, through the analysis of histomorfometric, the repair of complete tibial fracture in rabbits fixed with osteosynthesis, treated or not with infrared laser light (λ780 nm, 50 mW, CW) associated or not to the use of hydroxyapatite and guided bone regeneration (GBR). Surgical fractures were created, under general anesthesia (Ketamina 0,4 ml/Kg IP and Xilazina 0,2 ml/Kg IP), on the dorsum of 15 Oryctolagus rabbits that were divided into 5 groups and maintained on individual cages, at day/night cycle, fed with solid laboratory pelted diet and had water ad libidum. On groups II, III, IV and V the fracture was fixed with wire osteosynthesis. Animals of groups III and V were grafted with hydroxyapatite and GBR technique used. Animals of groups IV and V were irradiated at every other day during two weeks Observation time was that of 30 days. After animal death (overdose of general anesthetics) the specimes were routinely processed to wax and underwent histological analysis by light microscopy. The histomorfometric analysis showed an increased bone neoformation, increased collagen deposition, less reabsorption and inflammation when laser was associated to the HATCP. It is concluded that IR laser light was able to accelerate fracture healing and the association with HATCP and GBR resulted on increased deposition of CHA.
1364(2011); http://dx.doi.org/10.1063/1.3626914View Description Hide Description
Bell’s palsy is defined as a peripheral facial nerve palsy, idiophatic, and sudden onset and is considered the most common cause of this pathology. It is caused by damage to cranial nerves VII, resulting in complete or partial paralysis of the facial mimic. May be associated with taste disturbances, salivation, tearing and hyperacusis. It is diagnosed after ruling out all possible etiologies, because its cause is not fully understood.Some researches shows that herpes virus may cause this type of palsy due to reactivation of the virus or by imunnomediated post‐viral nerve demielinization. Physical therapy, corticosteroids and antiviral therapy have become the most widely accepted treatments for Bell’s palsy. Therapy with low‐level laser (LLLT) may induce the metabolism of injured nerve tissue for the production of proteins associated with its growth and to improve nerve regeneration. The success of the treatment of Bell’s palsy by using laser phototherapy isolated or in association with other therapeutic approach has been reported on the literature. In most cases, the recovery occurs without uneventfully (complications), the acute illness is not associated with serious disorders. We will present a clinical approach for treating this condition.
1364(2011); http://dx.doi.org/10.1063/1.3626915View Description Hide Description
PDT is a drug and device therapy using photosensitizing drugs activated by laser light, for tissue ablation. PDT light sources must deliver wavelengths matching the absorption of photosensitizers’ compound without any side thermal effect. According to applications, these sources need to be:
– pled to relatively small optical fibres so as to bring the light energy, of specific wavelength, inside of the body (gastroenterology, head & neck, urology, pneumology),
– coupled to a slit lamp adapter to transmit the light to the eye (AMD)
– or allow a direct illumination of tissues when large areas must be treated (dermatology).
But they also need to be user‐friendly with limited investment and installation costs.
So as to achieve the required effects, several light sources are available and will be used but practical and economical reasons have limited the number and types of these sources.
For PDT oncology applications, besides dermatology, it has also been necessary to develop specific light delivery systems based on optical fibres. These devices allow the treatment:
– of circular lumens such as oesophagus, bile ducts, lungs
– of solid volumes such as prostate, pancreas
– of surfaces such as in head and neck
– of empty volumes such as bladder, uterus, cervix.
Due to the variety of these treatments, a full family of sources has been developed from original sophisticated costly lasers to more recent easy‐to‐use diode laser systems. The aim of this presentation is to present the actual state of the art of actual available PDT tools, analyze their qualities and weaknesses, analyze the consequences of a good and/or bad choice or good and/or bad utilization on the quality of the therapeutic results and resulting side effects. It will also evaluate the short and medium term developments of new tools and their effect on the development of the therapy including economical aspects.
1364(2011); http://dx.doi.org/10.1063/1.3626916View Description Hide Description
Photochemical tissue bonding (PTB) is a promising sutureless technique for tissue repair. PTB is often achieved by applying a solution of rose bengal (RB) between two tissue edges, which are irradiated by a green laser to crosslink collagen fibers with minimal heat production. In this study, RB has been incorporated in chitosan films to create a novel tissue adhesive that is laser‐activated. Materials and Methods. Adhesive films, based on chitosan and containing ∼0.1wt% RB were manufactured and bonded to calf intestine by a solid state laser (wavelength Fluence spot size ∼5 mm). A single‐column tensiometer, interfaced with a personal computer, tested the bonding strength. K‐type thermocouples recorded the temperature (T) at the adhesive‐tissue interface during laser irradiation. Human fibroblasts were also seeded on the adhesive and cultured for 48 hours to assess cell growth. Results and Conclusion. The RB‐chitosan adhesive bonded firmly to the intestine The adhesion strength dropped to when the laser was not applied to the adhesive. The average temperature of the adhesive increased from to during laser exposure. Fibroblasts grew confluent on the adhesive without morphological changes. A new biocompatible chitosan adhesive has been developed that bonds photochemically to tissue with minimal temperature increase.
1364(2011); http://dx.doi.org/10.1063/1.3626917View Description Hide Description
Wound healing involves local and systemic responses that reflect the etiology of the lesion, type of tissue, systemic condition and others. Despite being essentially the same for different wounds, the pattern of healing may change due to intrinsic and/or extrinsic factors. The type of tissue has also to be considered. Several therapeutic approaches have been used to improve healing including phototherapies such as Laser, LEDs and Lamps. Their effects on soft and mineralized tissues are well reported. The choice of appropriated parameters is essential for the results of the treatment and includes wavelength, power density, energy, duration and frequency of application and others. We studied the effects of different types of light on the healing of both soft and mineralized tissues using different models. We found that the use of Laser and polarized light are effective on improving the healing of diabetic and undernourished animals. We also found that Laser light is capable of improving the healing of drug‐induced impairment and on increasing the survival rate of flaps on both diabetic and non‐diabetic animals. We have also studied and shown the influence of the laser parameters on the healing of surgical and laser wounds. Lately we verified the positive effect of LEDs on healing. We used Laser/LED light for improving bone healing in conditions such as in dental implants, autologous grafts, biomaterials and fractures. From these reports and our own experience we have no doubt whatsoever that the use of phototherapies, carried out with appropriate parameters, promotes quicker tissue repair.
1364(2011); http://dx.doi.org/10.1063/1.3626918View Description Hide Description
Failures on the sealing of the tooth apex are responsible for many failures of apical surgeries. The Er:YAG laser has been proposed as an alternative for the use of rotator instruments on surgical endodontics. 12 human extracted canines had root endodontic treatment being the apical limit was set at 1mm before the apical foramen and were distributed into 2 groups. On group I, apicectomy was performed with the Er:YAG laser (250 mJ/15 Hz). Apical cut was performed of perpendicular mode with 3mm from the apical foramen. On Group II, the same procedures and the same sequence as above was used, varying only the parameters of the Er:YAG laser (400 mJ/6 Hz). The specimens were divided into groups and fixed, by the cervical third, on wax. Impermeabilization of the residual root apical third was performed following the same procedures used in the cervical third but the residual apex was left free from the impermeabilization. After that, the roots were immersed in a 2% methylene blue solution and placed in a bacteriological oven for 48 h. The segments were visually observed and the one showing greatest level of dye leakage was selected and kept in individual container and coded accordingly. Apical staining was measured using a stereoscopic magnifying glass; a compass; and caliper. The results showed that Group I showed significantly different higher mean level of dye leakage There was a significantly difference between the groups. It is concluded that the apicectomies carried out with 400 mJ/6 Hz showed the smallest infiltration value.
1364(2011); http://dx.doi.org/10.1063/1.3626919View Description Hide Description
PURPOSE: To investigate differences in cost of endovenous laser therapy (EVLT) using a top‐down approach derived from the Annual Report versus a clinically orientated, bottom‐up approach at a single hospital. METHODS: Information was obtained from: the day‐case activity Service Line Report (SLR) income statement for general surgery, comparative data from the National Audit Commission, reference costs from the hospital finance department on 69 patients and calculations on individual treatment times and session slots (2 EVLT’s per 3.5 hr session) on 37 consecutive patients. Duration of treatment, consumables (over £3) and staff pay were also recorded. Overheads were estimated at 15% and adjustments were made based on location and length of stay. RESULTS: Using a top‐down approach with SLR data the total cost of EVLT was estimated at £963.78 per treatment after adjustments for services and consumables. This compares with £1,073.34 using national data. The hospital reference costs per treatment ranged from £767.56 overall by local procedure code (HRG‐QZ10B) to £2,353.79 with individual samples. In the bottom‐up approach median duration of EVLT was 86 mins (95% CI: 82–95, IQR: 26). With timed treatments median cost per individual treatment was £597.68 (95% CI: 587.65‐621.25, IQR: 67.87) compared to £647.28 per session slot. CONCLUSION: Cost estimations of EVLT demonstrate an up to 4‐fold difference. Lack of clinical engagement in the top‐down approach leads to overestimations. Overheads are underestimated with a bottom‐up approach. This variability should be accounted when comparing treatments or interpreting cost‐effectiveness analyses.
Study of Commercial Grade Aetoxisclerol by Optical Means, in View of Its Use in Varicose Vein Treatment1364(2011); http://dx.doi.org/10.1063/1.3626920View Description Hide Description
Aetoxisclerol (or Polidocanol in usual medical terms) is an intermediate sclerosing agent that contains a hydrophilic and a hydrophobic pole and acts by altering the surface tension at the interface between the endothelial cells and their environment. The understanding of the interaction between the Polidocanol and the target veins (tissues) becomes an important factor in utilizing it in varicose veins disease. More, it seems that the exposure of the tissues impregnated with this medicine to laser radiation emitted at 1.06 μm improves the efficiency of the treatment. Because the commercially available Aetoxisclerol is a mixture of substances, when it is exposed to laser radiation, one should consider, actually the interaction with all the compounds. The absorption spectra in UV‐VIS‐NIR spectral ranges are measured for Aetoxisclerol. We exposed it at pulsed Nd:YAG laser beam between 2–30 min at known irradiation doses. The possible mechanisms implied in improvement of the efficiency of the irradiated Polidocanol are discussed.
1364(2011); http://dx.doi.org/10.1063/1.3626921View Description Hide Description
Maybe the worst aspect of menopause is the decline of the quality of the sexual life. The aim of the study is to demonstrate the beneficial effects of laser therapy in comparison with topical application of estrogen preparations, for the treatment of vaginal atrophy and sexual dysfunctions induced by menopause. A total of 50 menopausal patients were examined during a one year period. The methods used for objectifying vaginal atrophy and sexual dysfunctions were history taking, local clinical exam and PAP smear. From this group, 40 patients had vaginal atrophy with sexual dysfunctions. They have been treated differently, being included in four groups: patients treated with local estrogens, patients treated with intravaginal laser therapy, patients treated with both laser therapy and estrogens, patients treated with estrogens and placebo laser therapy. Therapeutic benefit, improvement of vaginal atrophy and quality of sexual life, were objectified by anamnesis (questionnaire), local and general clinical examination and PAP smear. The best results have been obtained, by far, in the 3rd group, followed by the women treated only with laser. In conclusion, we can say that laser therapy is the best way for solving the sexual inconveniences of menopause.
1364(2011); http://dx.doi.org/10.1063/1.3626922View Description Hide Description
Introduction. Newer and newer technologies have been widely developed in recent years due to increasing need for aesthetic medicine procedures. Less invasive methods of skin imperfection and time‐related lesions removal, IPL (Intense Pulse Light) being one of them, are gaining more and more interest. The shorter the “downtime” for the patient is and the more efficient the procedure results, the more popular the method becomes. Materials and methods_Authors analyse the results of treatment of a 571 patients‐group (501 women and 70 men) aged 5–72 years in the period: October 2006–August 2010. IPL™ Quantum (Lumenis Ltd.) device with 560 nm. cut‐off filter was used. Results. The results were regarded as: very good, good or satisfying (%):Skin photoaging symptomes 37/40/23, Isolated facial dyschromia 30/55/25, Isolated facial erythema 62/34/4, Lower limbs teleangiectasia 12/36/52, Keratosis solaris on hands 100/‐/‐. Approximately half of the patients developed transitory erythema and 25%‐ transitory, mild, circumscribed oedema. Following undesirable effects were noted: skin thermal irritation (6,1% of the patients) and skin hypopigmentation (2% of the patients). Discussion. Results and post‐treatment management proposed by authors are similar to those reported by other authors. Conclusions. Treatment results of the 571‐patients group prove IPL to be a very efficient method of non‐ablative skin rejuvenation. It turned out effective also in lower limbs teleangiectasia treatment. It presents low risk of transitory and mild side effects. Futhermore, with short or no downtime, it is well‐tolerated by the patients.
1364(2011); http://dx.doi.org/10.1063/1.3626923View Description Hide Description
Pulse oximetry (PO) is extensively used in intensive care unit (ICU); this is mainly due to the fact that it is a non‐invasive and real‐time monitoring method. PO allows to measure arterial oxygen saturation and in particular hemoglobin oxygenation. Optical PO is typically realized by the use of a clip (to be applied on the ear or on the finger top) containing a couple of monochromatic LED sources and a photodiode. The main drawback with the use of PO is the presence of movement artifacts or disturbance due to optical sources and skin, causing erroneous saturation data. The aim of this work is to present the measurement procedure based on a specially developed algorithm able to reject erroneous oxygen saturation data during long lasting monitoring of patients in ICU and to compare measurement data with reference data provided by EGA.
We have collected data from a standard PO and used an intensive care unit monitor to collect data. This device was connected to our acquisition system and heart rate (HR) and data were acquired and processed by our specially developed algorithm and directly reproduced on the PC screen for use by the clinicians. The algorithm here used for the individuation and rejection of erroneous saturation data is based on the assessment of the difference between the Heart Rate (HR) measured by respectively by the ECG and PO. We have used an emogasanalyzer (EGA) for comparison of the measured data. The study was carried out in a neonatal intensive care unit (NICU), using 817 data coming from 24 patients and the observation time was of about 10000 hours.
Results show a reduction in the maximum difference between the data measured, simultaneously, on the same patient by the EGA and by the proposed method of 14.20% and of the 4.76% in average over the 817 samples. The measurement method proposed is therefore able to individuate and eliminate the erroneous saturation data due to motion artifacts and reported by the pulse oxymeter. Specifically in neonatal ICU, it allows to come to more efficient individuation of apnea, hypoxia and hyperoxia events and consequently to operate more adequate and efficient therapeutic actions.