Diode versus CO2 Laser Therapy in the Treatment of High Labial Frenulum Attachment: A Pilot Randomized, Double-Blinded Clinical Trial.

Background: The labial frenula are triangular plicas departing from the alveolar mucosa and attaching themselves at different heights of the gingiva. Sometimes a high attachment can determine a gingival recession. The most suitable surgical resolution is the use of laser devices. The aim of this study was to compare the labial frenulectomy through the use of Diode and CO2 laser techniques in pediatric patients with a high labial frenulum attachment, clarifying at the same time the preventive role of the surgical treatment to avoid further recession. Methods: A pilot randomized, double-blinded clinical trial was conducted to compare both the surgical advantages and the preventive treatment of laser technology using two different wavelengths within a population of pediatric patients with a high labial frenulum attachment. Different parameters intra and post-surgery were taken into account (Bleeding, Wound Healing, Gingival Recession, Periodontal pocket and Numerical Scale Value for pain) to compare Diode versus CO2 laser therapy. Results: Although both the laser devices provide a good performance in the post-operative period, the Diode laser shows better results (p < 0.001) in three of the five parameters evaluated. Conclusions: From the results it was found that the Diode Laser device is more suitable compared to the CO2 device.

Evaluating the Laser Output of the Micropulse P3 Laser Delivery Device Following Repeated Use.

PRECIS: Repeated use of the Micropulse P3 (MP3) probe during micropulse transscleral cyclophotocoagulation is associated with an increase in laser output over time. PURPOSE: The purpose of this study was to examine the laser efficacy of the MP3 probe following repeated use. METHODS: This was an observational study carried out using Cyclo G6 Glaucoma Laser System with 6 MP3 laser delivery probes. Each probe was fired for 100 seconds, every 10 minutes until the probe was deactivated. The laser output was measured using a laser power meter. Maximum observed laser power output was also noted. RESULTS: All probes were deactivated after 90 minutes (9 cycles) of use. Mean laser output of all 6 probes was determined, and results suggested an increase in output with time. When examining the differences in total laser output for each cycle, no significant differences were observed for the first 4 cycles, but not for the remaining 5 cycles, wherein the increased laser outputs were found to be significantly different from baseline (cycle 1). CONCLUSION: Findings suggest a possible increase in laser output with repeated use, especially after 4 cycles, and clinicians need to be cautious if they intend to use the probes repeatedly.

Choosing a laser for laser speckle contrast imaging.

The use of laser speckle contrast imaging (LSCI) has expanded rapidly for characterizing the motion of scattering particles. Speckle contrast is related to the dynamics of the scattering particles via a temporal autocorrelation function, but the quality of various elements of the imaging system can adversely affect the quality of the signal recorded by LSCI. While it is known that the laser coherence affects the speckle contrast, it is generally neglected in in vivo LSCI studies and was not thoroughly addressed in a practical matter. In this work, we address the question of how the spectral width of the light source affects the speckle contrast both experimentally and through numerical simulations. We show that commonly used semiconductor laser diodes have a larger than desired spectral width that results in a significantly reduced speckle contrast compared with ideal narrow band lasers. This results in a reduced signal-to-noise ratio for estimating changes in the motion of scattering particles. We suggest using a volume holographic grating stabilized laser diode or other diodes that have a spectrum of emitted light narrower than ≈1 nm to improve the speckle contrast.

Subthreshold micropulse laser photocoagulation therapy in a case of bilateral retinal astrocytic hamartomas with tuberous sclerosis complex: A case report.

RATIONALE: Report a case of bilateral multiple retinal hamartomas (RAHs) in a patient with tuberous sclerosis complex (TSC) and introduced a new method (subthreshold micropulse laser photocoagulation) for the treatment of RAHs. PATIENT CONCERNS: A 20-year-old man with TSC complained of decreased vision and metamorphosia in both eyes for 2 months. At presentation, visual acuity (VA) was 20/32 in the right eye and 20/40 in the left eye. Fundus photographs, optical coherence tomography, fundus fluorescein angiography (FFA), and indocyanine green angiography indicated multiple RAHs in both eyes. DIAGNOSES: Bilateral retinal astrocytic hamartomas. INTERVENTIONS: In the right eye, 577 nm photocoagulation was adopted to treat the RAHs with obvious fluorescein leakage in FFA. The paramacular RAHs were treated by subthreshold micropulse mode to minimize the damage to macula. Photocoagulation therapy was administrated in the left eye after 1 dose of intravitreal ranibizumab treatment. OUTCOMES: After photocoagulation therapy (including subthreshold micropulse laser photocoagulation for the paramacular RAHs in both eyes), the VA improved to 20/25 OD and 20/32 OS with no recurrence of exudation. LESSONS: About 577 nm photocoagulation for the peripheral RAHs in combination with subthreshold micropulse laser photocoagulation for RAHs in the macular zone is a good option for multiple RAHs in patients with TSC.

Diode laser versus radiofrequency treatment of the inferior turbinate - a randomized clinical trial.

BACKGROUND: Laser and radiofrequency induced volume reduction of the inferior turbinates are frequently used treatment modalities. Which of both is superior, however, is not clear to date due to a lack of controlled prospective studies. Here, we compare both methods regarding improvement of nasal breathing, complications, patient comfort and wound healing. METHODOLOGY: Prospective, randomized, single-blinded clinical trial with intra-individual design. After randomization, one side of the nose was treated with a 940nm diode laser and the other side with bipolar radiofrequency therapy. Pre- and postoperative evaluation was performed using visual analogue scales, nasal endoscopy and objective measurements of nasal patency. RESULTS: Of 27 enrolled patients, 26 completed the protocol. No severe complications were observed. Intraoperative discomfort was significantly more severe on the radiofrequency side. After three months, a significant reduction of nasal obstruction was observed for laser treatment and radiofrequency therapy with no significant difference between them. Objective parameters did not improve significantly. When asked which treatment modality they would chose again 50 % of the patients decided for radiofrequency treatment, 23 % for laser treatment, and 19 % for both. CONCLUSION: DLVR and RFVR are well-tolerated treatment modalities and both significantly reduce the degree of nasal obstruction in patients with hypertrophic inferior turbinates. There was no significant difference between both treatment modalities regarding efficiency.

The detection of iron protoporphyrin (heme b) in phytoplankton and marine particulate material by electrospray ionisation mass spectrometry - comparison with diode array detection.

A mass spectrometric (MS) method for the identification of iron protoporphyrin (IX) (FePTP, heme b) in marine particulate material and phytoplankton is described. Electrospray ionisation of FePTP produced the molecular Fe(III)PTP(+) ion (m/z=616) or the pseudomolecular [Fe(II)PTP + H](+) ion (m/z=617), depending on the oxidation state of the central iron ion. Collision induced dissociation (CID) in the ion trap mass spectrometer resulted in a single detected product ion (m/z=557) indicative of loss of ethanoic acid from a carboxylic acid side chain. Widening the isolation width to 616±3 resulted in production of a mass spectrum demonstrating the distinctive isotopic ratio of the iron containing fragment, further increasing the specificity of the analysis. Selective reactant monitoring (SRM) of the fragment ion (m/z=557) was applied to the detection of FePTP after chromatography of ammoniacal OGP extracts of marine samples. The detection limit for FePTP analysed by SRM after chromatography was 1.2±0.5fmol. For phytoplankton samples, reasonably good agreement was achieved between results obtained with SRM and those obtained by monitoring absorbance at λ=400nm using a diode array detector (DAD). Use of SRM for analysis of particulate material obtained from the high latitude North Atlantic allowed for the analysis of FePTP in the presence of a co-eluting compound that interfered with detection by DAD. Simultaneous collection of mass spectra from m/z=300 to 1500 resulted in identification of the pseudomolecular ion for the interfering compound. The CID fragmentation pattern and UV-visible mass spectra indicated that the interfering compound was a previously unidentified chlorin type compound. Comparison of FePTP determined by SRM and DAD on samples where this compound could not be detected showed that results collected using the two methods correlated. The use of both MS and DAD results in a powerful tool for quantifying this important biogenic component of the particulate iron pool.

Adjunctive use of the diode laser in non-surgical periodontal therapy: exploring the controversy.

PURPOSE: Despite the controversy regarding clinical efficacy, dental hygienists use the diode laser as an adjunct to non-surgical periodontal therapy. The technique to maximize successful laser therapy outcome is controversial as well. The purpose of this review is to explore the scientific foundation of the controversy surrounding the use of the diode laser as an adjunct to non-surgical periodontal therapy. Further, this paper addresses the weaknesses in study design, the heterogeneity of methodology in the published clinical studies, especially the laser parameters, and how these issues impact the collective clinical and microbial data, and thus conclusions regarding clinical efficacy. Evaluation of the literature identifies possible mechanisms that could contribute to the varied, often conflicting results among laser studies that are the foundation of the controversy surrounding clinical efficacy. These mechanisms include current paradigms of periodontal biofilm behavior, tissue response to laser therapy being dependent on tissue type and health, and that the successful therapeutic treatment window is specific to the target tissue, biofilm composition, laser wavelength, and laser energy delivered. Lastly, this paper discusses laser parameters used in the various clinical studies, and how their diversity contributes to the controversy. Although this review does not establish clinical efficacy, it does reveal the scientific foundation of the controversy and the need for standardized, well designed randomized controlled clinical trials to develop specific guidelines for using the laser as an adjunct to non-surgical periodontal therapy. Using evidence-based laser guidelines would allow dental hygienists to provide more effective non-surgical periodontal care.

Laserlipólise com diodo 980 nm: experiência com 400 casos / Laser lipolysis with a 980-nm diode laser: experience with 400 cases

INTRODUÇÃO: A técnica de lipoaspiração recebeu várias contribuições desde sua primeira descrição, como modificações nas cânulas, variação na concentração da solução de infiltração e uso de aparelhos com tecnologias variadas. A utilização de aparelhos com tecnologia laser vem contribuir com o procedimento por meio da lipólise e com o estímulo de retração cutânea. Neste artigo é apresentada a experiência dos autores com a laserlipólise em 400 pacientes, no intervalo de 5 anos, sendo discutidos aspectos dos princípios da tecnologia e sua ação sobre os tecidos. MÉTODO: Estudo realizado entre julho de 2007 e julho de 2012, que incluiu 400 pacientes submetidos a procedimento de laserlipólise. Os procedimentos foram realizados seguindo protocolo original, com infiltração de soro gelado, passagem da cânula com fibra óptica para a condução da energia laser visando à laserlipólise, retração cutânea e, por último, lipoaspiração convencional. RESULTADOS: O período de internação variou de cirurgia em regime ambulatorial a pernoite. Cerca de 45% (180/400 pacientes) dos pacientes evoluíram com equimoses mínimas, com acometimento de 2% ou mais da superfície corporal comprometida. Os casos de hematoma, seroma e deiscência totalizaram 9% (36/400 pacientes). Em nenhum caso foi constatada queimadura por lesão térmica na pele. CONCLUSÕES: O procedimento de laserlipólise realizado com a técnica descrita demonstrou segurança e reprodutibilidade.

INTRODUCTION: Liposuction has undergone several improvements since its first description, including changes in the cannulas, variation in the concentration of the infiltrating solution, and the use of different devices and technologies. The use of laser technology devices for lipolysis and stimulation of skin retraction has contributed to the procedure. This article presents the authors' experience with laser lipolysis in 400 patients, within a 5-year period, and discusses the principles of the technology and its effect on tissues. METHODS: This is a study performed between July 2007 and July 2012 and included 400 patients who underwent laser lipolysis. All procedures were performed following the original protocol - infiltration of cold saline, passage of the cannula with an optic fiber for conducting the energy needed for laser lipolysis, skin retraction, and finally, conventional liposuction. RESULTS: Hospitalization type ranged from outpatient to overnight surgery. Approximately 45% (180 of 400) of patients had minimal bruising, with involvement of 2% or more of the affected body surface. Hematoma, seroma, and dehiscence occurred in a total of 9% (36 of 400) of patients. We did not find any case of thermal burn of the skin. CONCLUSIONS: Laser lipolysis performed according to the described technique was safe and reproducible.

Evaluation of a diode laser for use in induction of tendinopathy in the superficial digital flexor tendon of horses.

OBJECTIVE: To evaluate use of a diode laser to induce tendinopathy in the superficial digital flexor tendon (SDFT) of horses. ANIMALS: 4 equine cadavers and 5 adult horses. PROCEDURES: Cadaveric SDFT samples were exposed to a diode laser at various energy settings to determine an appropriate energy for use in in vivo experiments; lesion size was assessed histologically. In vivo experiments involved laser energy induction of lesions in the SDFT (2 preliminary horses [0, 25, 75, and 87.5 J] and 3 study horses [0 and 125 J]) and assessment of lesions. Study duration was 21 days, and lesions were assessed clinically and via ultrasonography, MRI, and histologic evaluation. RESULTS: Lesion induction in cadaveric tissues resulted in a spherical cavitated core with surrounding tissue coagulation. Lesion size had a linear relationship (R2 = 0.9) with the energy administered. Size of in vivo lesions in preliminary horses indicated that larger lesions were required. In study horses, lesions induced with 125 J were ultrasonographically and histologically larger than were control lesions. At proximal and distal locations, pooled (preliminary and study horses) ultrasonographically assessed lesions were discrete and variable in size (mean ± SEM lesion percentage for control lesions, 8.5 ± 3%; for laser lesions, 12.2 ± 1.7%). Ultrasonography and MRI measurements were associated (R2 > 0.84) with cross-sectional area measurements. CONCLUSIONS AND CLINICAL RELEVANCE: In vivo diode laser-induced lesions did not reflect cadaveric lesions in repeatable size. Further research is required before diode lasers can reliably be used for inducing tendinopathy.

[Comparative experimental morphological study of efficacy and safety of near-infrared and visible wave-length laser iridoplasty].

The features of interaction of laser radiation with iris tissue were determined in experimental morphological study. The potential of laser irradiation with different spectral characteristics for pupil ectopia correction is estimated. The results of morphometry showed effectiveness of near-infrared diode laser radiation, that presents as an iris contraction in coagulation region with minimal tissue trauma. This fact allows us to propose a near-infrared diode laser radiation as a treatment option for correction of pupil form and location. Alternatively visible wave-length laser showed to be less effective and more traumatic.

Generalization of DT equations for time dependent sources.

New equations for paralyzable, non paralyzable and hybrid DT models, valid for any time dependent sources are presented. We show how such new equations include the equations already used for constant rate sources, and how it's is possible to correct DT losses in the case of time dependent sources. Montecarlo simulations were performed to compare the equations behavior with the three DT models. Excellent accordance between equations predictions and Montecarlo simulation was found. We also obtain good results in the experimental validation of the new hybrid DT equation. Passive quenched SPAD device was chosen as a device affected by hybrid DT losses and active quenched SPAD with 50 ns DT was used as DT losses free device.

Láser de diodo-980 mm de alta potencia: resultados preliminares en el tratamiento de la hiperplasia benigna de próstata / High power 980 NM Diode Laser: preliminary results in the treatment of benign prostatic hyperplasia

OBJETIVO: Evaluar clínicamente la utilización de un láser de diodo de 980 nm en el tratamiento de la uropatía obstructiva infravesical secundaria a hiperplasia benigna de próstata (HBP), poniendo énfasis en la morbilidad perioperatoria y los resultados en un seguimiento a corto plazo.MÉTODOS: Quince pacientes fueron incluidos en el estudio. Todos fueron evaluados mediante los cuestionarios IPSS y de calidad de vida (CV), tacto rectal, PSA, ecografía y flujometría. Se procedió a la vaporización prostática con un láser de diodo de 980 nm (120 W; Intermedic; Barcelona, España) utilizando una fibra de disparo lateral de 600 micras. En el seguimiento se recogió cualquier incidencia, así como la puntuación en los cuestionarios IPSS y CV así como en el pico de flujo máximo.RESULTADOS: La edad media de los pacientes fue de 66,7 años (45-75). El rango del volumen prostático fue 20-76 cc (media 41,3 cc). La media de energía utilizada fue de 161,012 kJ (78,3-243). Ningún paciente presentó una pérdida hemática significativa ni síndrome de absorción líquida. En todos los casos se colocó un catéter uretral 22F que se retiró entre las 12-40 horas postoperatorias. Tras un seguimiento medio de 5,5 meses (2-9), la puntuación media en el cuestionario IPSS y en el de CV variaron, respectivamente, de una media de 22,4 (19-26) y de 3 (2-4) previa a la intervención, hasta una media de 6,8 (1-13) (p<0,01) en el cuestionario IPSS y de 1,4 (0-3) en el de CV al final del seguimiento (p<0,01). De igual modo, el flujo máximo se incrementó de 6,4 ml/s (5-11,9) en el preoperatorio a 19,7 ml/s (13,9-24) en el postoperatorio (p<0,01).Ningún paciente presenta incontinencia. No se ha requerido la repetición del procedimiento, si bien tres pacientes precisaron un sondaje transitorio en las primeras 48h (dos de los pacientes eran portadores de sonda vesical antes del tratamiento)(AU)

CONCLUSIONES: Nuestros resultados preliminares sugieren que la vaporización prostática con láser de diodo de 980 nm utilizando potencias de hasta 120 W es efectiva y asociada a escasa morbilidad(AU)

OBJECTIVES: A clinical evaluation of the use of a 980 nm diode laser in the treatment of bladder outlet obstruction secondary to benign prostatic hyperplasia (BPH), focused on perioperatory morbidity and results in a short-term follow-up.METHODS: Fifteen patients were included in the study. All of them were evaluated by IPSS and Quality of Life (QoL) questionnaires, digital rectal examination, PSA, ul-trasound scan and uroflowmetry. Prostate vaporization was performed with a laser of diode at 980 nm (Inter-medic; Barcelona, Spain) using a 600 microns side-fire fiber. In the follow-up any event was recorded, as well as the IPSS and QoL scores and Qmax.RESULTS: Mean age of the patients was 66.7 years(45-75). The range of prostate volume was 20-76 cc (median 41.3 cc). Mean delivered energy was 161,012 kJ (78,3-243). No patient showed either a significant hematic loss or fluid absorption syndrome. A 22F urethral three-way catheter was inserted and removed between 12-40 hours in the postoperatory period. After a mean follow-up of 5,5 months (2-9) the average IPSS and QOL questionnaires scores changed, respectively, from 22,4 (19-26) and from 3 (2 -4) to an average of 6,8 (1 – 13) (p<0,01) and 1,4 (0 – 3), respectively, at the end of follow-up (p <0,01). Qmax increased from 6,4 ml/s (5-11,9) baseline to 19,7 ml/s (13,9-24 (p <0,01). No patient showed urinary incontinence. Retreatment was not nee-ded though three patients needed a short-time catheterization (24 hours) after developing acute urinary retention in the first 48h hours.CONCLUSIONS: Our preliminary results suggest that prostate vaporization using 980 nm diode laser with output power up to 120 W, is effective and associated to minimal morbidity(AU)

Preliminary evaluation of a novel side-fire diode laser emitting light at 940 nm, for the potential treatment of benign prostatic hyperplasia: ex-vivo and in-vivo investigations.

OBJECTIVES: To evaluate, ex vivo and in vivo, the tissue-removal capacity and coagulation properties of a diode laser emitting light at 940 nm, as in the search for potential therapeutic strategies for benign prostatic hyperplasia that cause less morbidity than transurethral resection of the prostate (TURP), various types of lasers have been tested. MATERIALS AND METHODS: A diode laser system (prototype; wavelength 940 nm, Dornier MedTech, Wessling, Germany) was evaluated in an isolated, blood-perfused ex-vivo porcine kidney model at 10-60 W (five kidneys). An in-vivo beagle model was used to investigate the effects on six prostate lobes at a generator output power level of 200 W. After the laser treatment tissue were examined histologically to compare the depth of coagulation and vaporization. RESULTS: With increasing generator output power levels there was an increasing vaporization and coagulation ability for the diode laser at 940 nm in the ex-vivo model. At 60 W the mean (sd) vaporization depth was 1.72 (0.47) mm with a coagulation zone of 9.56 (0.26) mm. In vivo, the diode laser caused rapid ablation with no intraoperative haemorrhage. Histologically, the zone of coagulation had a mean (sd) depth of 4.25 (0.15) mm at 200 W. The tissue removal capacity was estimated at 0.874-1.583 g/min in vivo. CONCLUSIONS: Our findings indicate that diode-laser vaporization at 940 nm is feasible and might be effective for acutely relieving bladder outlet obstruction in an in-vivo setting. Due to its mean coagulation zone of 4.25 mm the diode laser seems to have effective haemostatic properties.

[Frequency stabilization of diode laser using zeeman spectra].

Zeeman split takes place for the hyperfine level structure of neutral atoms where magnetic field exists. In addition, being excited by right circularly polarized light and left circularly polarized light, atoms obey different transition rules. So, the absorption peak between the hyperfine Zeeman level shifts with respect to the absorption peak without magnetic field. Accordingly, the authors demonstrated a kind of simple and flexible method to stabilize the frequency of diode laser. The linewidth of diode laser was reduced to less than 1 MHz using this method. Through analyzing the experiment results, the authors found that when the sum of both shifts of the hyperfine level of atoms excited by right circularly polarized light and left circularly polarized light was equal to the FWHM (Full Width at Half Maximum) of the saturated absorption peak, the laser frequency was stabilized best.