Medical laser application : international journal for laser treatment and research最新文献

Objective

Our purpose was to determine the efficacy of low level laser therapy (LLLT) on wound healing in rabbits.

Study design

Sixteen rabbits were sedated and given a general anesthetic. A full thickness flap was used bilaterally at the buccal gingiva maxilla in a naturally toothless area, and then sutured. A low level pulsed GaAlAs laser (wavelength: 685 nm, power: 45 mW, radiant exposure: 3 J/cm², frequency: 10 Hz, duty factor: 80%; application time: 1 min) was used on the left side. The right side was not lasered as a control. Tissue specimens from each site on days 3, 7, and 14 after surgery were examined microscopically.

Results

Less inflammation was observed on days 3 and 7 in the treatment group (p < 0.01). The inflammation rate on both sides was the same on day 14 (p > 0.05).

Conclusion

LLLT using optimal parameters can accelerate full thickness wound healing.

Zielsetzung

Untersuchung des Effekts einer Low-Level-Laser-Therapie (LLLT) mittels GaAlAs-Laser auf die postoperative Wundheilung von Hasen.

Studiendesign

Bei 16 Hasen wurden unter Allgemeinanästhesie beidseitig sogenannte „Full-thickness Flaps” der Gingiva buccalis des Oberkiefers präpariert und anschließend wieder vernäht. Die linke Seite wurde mittels LLLT unter Einsatz eines gepulsten GaAlAs-Lasers (Wellenlänge: 685 nm, Laserleistung: 45 mW, Bestrahlung: 3 J/cm², Frequenz: 10 Hz, Einschaltdauer: 80%) behandelt, die rechte Seite wurde nicht gelasert (Kontrollgruppe). Für beide Untersuchungsgruppen (behandelt/unbehandelt) wurden 3, 7 und 14 Tage nach der Operation Gewebeproben entnommen und mikroskopisch untersucht (Zählung der Entzündungszellen).

Ergebnisse

In der LLLT-Gruppe wurde 3 und 7 Tage postoperativ ein geringerer Entzündungsgrad festgestellt als in der Kontrollgruppe (p < 0,01). 14 Tage nach der Operation unterschied sich der Entzündungsgrad beider Untersuchungsgruppen nicht mehr signifikant (p > 0,05).

Zusammenfassung

Die LLLT kann bei optimaler Parameterauswahl die Wundheilung beschleunigen.

The four most popular search engines PubMed/MEDLINE, ScienceDirect, Scopus and Google Scholar are investigated to assess which search engine is most effective for literature research in laser medicine. Their search features are described and the results of a performance test are compared according to the criteria (1) recall, (2) precision, and (3) importance. As expected, the search features provided by PubMed/MEDLINE with a comprehensive investigation of medical documents are found to be exceptional compared to the other search engines. However the most effective search engine for an overview of a topic is Scopus, followed by ScienceDirect and Google Scholar. With regard to the criterion “importance” Scopus and Google Scholar are clearly more successful than their competitors.

In diesem Artikel werden die 4 populärsten Suchmaschinen PubMed/MEDLINE, ScienceDirect, Scopus und Google Scholar beschrieben und deren Leistungsfähigkeit bezüglich der Sucheffektivität auf dem Gebiet der Lasermedizin verglichen. Die Beurteilung der Leistungsfähigkeit erfolgte nach den Kriterien (1) Trefferanzahl, (2) Präzision der Treffer und (3) Wichtigkeit der gefundenen Artikel. Die letzten beiden Kriterien wurden anhand von hier vorgestellten Formeln berechnet.

Generell sind die Möglichkeiten, die die Suchmaschinen für die Literaturrecherche anbieten, akzeptabel, nur Google Scholar fällt hier etwas aus dem Rahmen und bietet deutlich weniger Möglichkeiten.

Wie erwartet sind die Suchwerkzeuge, die PubMed/MEDLINE anbietet, im Hinblick auf eine umfassende und tiefgreifende Literaturrecherche von medizinischen Dokumenten von allen anderen getesteten Suchmaschinen unerreicht. Da PubMed/MEDLINE jedoch nicht die Möglichkeit bietet, die Treffer nach Relevanz oder Wichtigkeit zu sortieren, erweisen sich die anderen Suchmaschinen aber als deutlich effektiver, wenn es darum geht sich einen schnellen Überblick über relevante Literatur zu einem bestimmten Thema zu verschaffen. Insbesondere Scopus ist in diesem Punkt die leistungsfähigste Suchmaschine.

Introduction

Laser vaporization of the prostate with the GreenLight laser has emerged as a treatment alternative to TURP.

Materials and methods

An analysis of the published data of our center was performed to assess the safety, the efficacy and the long-term results of the technique.

Results

GreenLight laser vaporization of the prostate is characterized by an outstanding intraoperative safety, regardless of oral anticoagulation or prostate size. The early and midterm functional outcome are comparable to TURP, however the data lack randomization.

Conclusions

Laser vaporization of the prostate with the GreenLight laser is a safe and effective treatment modality for patients with bladder outlet obstruction due to benign prostate enlargement and has gained wide acceptance in the urological community.

Background and objectives

Laser radiation in the 2 μm wavelength region is well-absorbed by water and has good transmittance through commercially available, low-OH quartz optical fibers which are generally acknowledged to have great potential for medical application in endoscopic and open surgery. Medical laser systems in this wavelength range are flashlamp- or laser-pumped pulsed Ho:YAG lasers and continuous wave (cw) thulium (Tm)-doped fiber lasers. This paper presents the laser–tissue effects on an ex-vivo tissue model using an innovative diode-pumped cw Tm:YLF laser and cw and Q-switched Ho:YAG laser.

Materials and methods

The diode-pumped air-cooled Tm:YLF laser (IAP RAS prototype) emits cw light at 1909 nm with an output power of up to 20 W and an optic-to-optic efficiency of more than 41%. The Ho:YAG laser (IAP RAS prototype) is pumped by the radiation of a Tm:YLF laser and can operate at 2090 nm in cw or Q-switched mode with an average power of up to 10 W. The laser beam quality of both lasers is about M² < 1.3 and can be easily coupled in low-OH optical fibers.

Laser–tissue interaction experiments were performed using porcine kidney and liver tissue. Single-spot and cutting experiments were performed in a reproducible set-up. In the single-spot experiments, a fixed distance was used between fiber and tissue surface of d = 5 mm and energies were applied in the 10–200 J range. The cutting experiments were performed with the same laser parameters but in contact mode (d = 0 mm) using a constant scanning velocity of $v=1\text{mm/s}$ of the linear fiber movement. Macroscopic and histological evaluations were performed.

Results

The tissue effect showed precise and reproducible ablation. The ablation depth depended on the applied power. Interestingly, the histological findings showed that the thickness of the coagulation zone in lateral and axial plane was nearly constant at 1 ± 0.5 mm in each direction.

Conclusion

The presented lasers showed more flexibility for surgical approaches. The induced tissue effects showed a very high reproducibility in ablation and in coagulation for both radial and axial planes. The constant small size of these effects may show the potential for precise laser-assisted surgical preparation.

Background

Pilonidal sinus disease (PSD) is a debilitating disease arising in the hair follicles of the sacrococcygeal region. We describe our 5-year experience of managing recurrent cases with laser depilation using an 800 nm diode laser (LightSheer EP, Lumenis-Yokneam, Israel).

Patients and methods

A retrospective study was undertaken from June 2003 to June 2008. A total of 15 patients who had undergone laser depilation were included. Each patient was scheduled for 3 treatments at 6-weekly intervals. Patients were followed up for 12 months and were telephoned to ascertain disease status after the period of the formal follow-up.

Results

The majority of patients underwent at least one surgical episode (range: 1–4, mean: 2.3). Seven patients had unhealed pilonidal wounds which did not respond to conservative management. Three patients did not complete their course of treatment and one suffered a recurrence after 22 months. Following laser depilation, all seven patients with chronic non-healing wounds were healed. At the end of the study period, all patients except one remained disease free (range: 6–50 months, mean: 23.6 months).

Conclusion

Recurrence of PSD can be controlled with good perineal hygiene and regular shaving of the natal cleft; however this can be difficult and awkward. Laser hair depilation is a useful adjunct to preventing recurrence and we believe it should be routinely offered to patients who have recurrent disease. The use of laser in the treatment of chronic sinus disease also appears to hasten and aid healing; however this needs further evaluation and investigation.