Lasers in Surgery and Medicine
0196-8092
1096-9101
Mỹ
Cơ quản chủ quản: Wiley-Liss Inc. , WILEY
Lĩnh vực:
DermatologySurgery
Các bài báo tiêu biểu
Initiation of apoptosis and autophagy by photodynamic therapy Abstract Background and Objectives This study was designed to examine modes of cell death after photodynamic therapy (PDT). Study Design Murine leukemia L1210 cells and human prostate Bax‐deficient DU145 cells were examined after PDT‐induced photodamage to the endoplasmic reticulum (ER). Phase contrast, fluorescence and electron microscopy were used to identify changes in cellular morphology, chromatin condensation, loss of mitochondrial membrane potential, and formation of phagolysosomes. Western blots were used to assess the processing of LC3‐I to LC3‐II, a marker for autophagy. Inhibitors of apoptosis and/or autophagy were used to delineate the contributions of the two pathways to the effects of PDT. Results Both apoptosis and autophagy occurred in L1210 after ER photodamage with the latter predominating after 24 hours. In DU145 cells, PDT conditions causing comparable cytotoxicity only initiated autophagy. PI3‐kinase inhibitors suppressed autophagy in both cell lines as indicated by inhibition of vacuolization and LC3 processing. Conclusions Both autophagy and apoptosis were observed in L1210 cells following ER photodamage. In the Bax‐deficient DU145 cell line only autophagy was observed. Current information suggests that autophagy can function as either a survival or death pathway. We propose that in the context of PDT, this may also be true. Lasers Surg. Med. © 2006 Wiley‐Liss, Inc.
Tập 38 Số 5 - Trang 482-488 - 2006
Cell biology of hematoporphyrin derivative (hpd) Abstract Tissue culture cells were treated with hematoporphyrin derivative (HPD) and analyzed for (1) HPD uptake, (2) HPD washout, and (3) fluorescence changes. The absorption peaks were the same for HPD in solution and HPD bound to cells. HPD was taken up by all cell types rapidly within the first 10 hours of exposure, and leveled off by 20 hours of exposure. HPD came out of all cell types to control levels by 72 hours after removal of the HPD bathing solution. The HPD appeared to come out of the malignant 3‐T‐12 cells more slowly than from the parental (non‐malignant) 3‐T‐3 cells. The fluorescence spectrum of HPD‐treated cells changed markedly from the time that the bathing HPD solution was removed from the cells. As time progressed the weakly fluorescent 590‐nm peak increased greatly and the 615‐nm and 630‐nm peaks decreased significantly.
Tập 2 Số 3 - Trang 261-266 - 1983
Possible hazards from irradiation with the carbon dioxide laser Abstract Previous investigators, using relatively high irradiance levels, have been unable to demonstrate viable tissue in the plume during carbon dioxide laser vaporization. Our study was undertaken to reinvestigate this possibility, particularly at the lower irradiance levels that are currently in clinical use. Fresh post‐mortem skin was injected with a known quantity of bacterial spores and vaporized at different levels of irradiance and energy fluence. The plume and splatter were collected and cultured. Spores were found following the vaporization of five of 13 specimens treated at an irradiance of <500 W/cm2 , while there were none in the 20 specimens treated at an irradiance of >997 W/cm2 . These results show that the widely accepted assumption that the carbon dioxide laser produces a sterile field may be false and that viable particles may be disseminated during vaporization at low irradiance. This may be important when considering the treatment of potentially infectious lesions.
Tập 6 Số 1 - Trang 84-86 - 1986
MR‐guided laser‐induced thermal therapy (LITT) for recurrent glioblastomas Abstract Background and objective Laser‐induced thermal therapy (LITT), coupled with magnetic resonance thermal imaging (MRTI) guidance, provides a minimally invasive and safe approach to treat brain tumors, especially metastases. We report here our experience using this treatment for recurrent glioblastomas. Materials and Methods Four patients, from 40 to 58 years old, were diagnosed with glioblastoma. After total resection, chemotherapy and radiation therapy, recurrence occurred. As each was ineligible for a second surgery, LITT was proposed as salvage therapy. Under stereotactic guidance, a fiberoptic applicator was inserted within the tumor LITT was performed under continuous MRTI. Real‐time feedback control based on MRTI was employed to assess the quality of local tissue destruction and to prevent unwanted damage to nearby structures. Results The procedure was well tolerated with no peroperative neurological deterioration. In the short‐term follow‐up, one transient supplementary motor area syndrome, one epileptic seizure, and one cerebrospinal fluid leakage occurred. All were successfully managed. Post‐procedure MRI showed no complication, satisfying treatment volume, and a decrease in size of the treated tumor. For all patients, recurrence was observed with a mean/median progression free survival of 37/30 days. Mean/median overall survival after LITT was 10.5/10 months. Conclusion Focal tumor control was performed safely using minimally invasive LITT with real‐time MRTI control. LITT could be considered as salvage therapy for high‐grade recurrent gliomas if a 1‐day treatment is considered useful for a few weeks gain in survival. Larger experience will be required to define indications for such infiltrative disease and accurately determine a potentially significant survival gain in good neurological condition associated with this 1‐day procedure. Lasers Surg. Med. 44: 361–368, 2012. © 2012 Wiley Periodicals, Inc.
Tập 44 Số 5 - Trang 361-368 - 2012
Laser thermal therapy: Real‐time MRI‐guided and computer‐controlled procedures for metastatic brain tumors Abstract Background and Objective We report the final results of a pilot clinical trial exploring the safety and feasibility of real‐time magnetic resonance‐guided laser‐induced thermal therapy (MRgLITT) for treatment of resistant focal metastatic intracranial tumors. Study Design In patients with chemotherapy, whole‐brain radiation, and radiosurgery resistant metastatic intracranial tumors, minimally invasive stereotaxic placement of a saline‐cooled interstitial fiberoptic laser applicator under local anesthesia was followed by laser irradiation during continuous magnetic resonance imaging (MRI) scanning. A computer workstation extracted real‐time temperature‐sensitive information for feedback control over laser delivery. A total of 15 metastatic tumors were treated in 7 patients. Patients were followed with physical exam and imaging for 30 months. Results In all cases, the procedure was well tolerated, and patients were discharged home within 24 hours. Follow‐up imaging at up to 30 months showed an acute increase in apparent lesion volume followed by a gradual and steady decrease. No tumor recurrence within thermal ablation zones was noted. Kaplan–Meier analysis indicated that the median survival was 19.8 months. Conclusion Real‐time magnetic resonance (MR) guidance of laser‐induced thermal therapy (LITT) offers a high level of control. This tool therefore enables a minimally invasive option for destruction and treatment of resistant focal metastatic intracranial tumors. MR‐guided LITT appears to provide a safe and potentially effective treatment for recurrent focal metastatic brain disease. A larger phase II and III series would be of interest to quantify potential median survival advantage. Lasers Surg. Med. 43:943–950, 2011. © 2011 Wiley Periodicals, Inc.
Tập 43 Số 10 - Trang 943-950 - 2011
In vivo optical coherence tomography for the diagnosis of oral malignancy Abstract Background and Objective Oral cancer results in 10,000 U.S. deaths annually. Improved highly sensitive diagnostics allowing early detection of oral cancer would benefit patient survival and quality of life. Objective was to investigate in vivo non‐invasive optical coherence tomography (OCT) techniques for imaging and diagnosing neoplasia‐related epithelial, sub‐epithelial changes throughout carcinogenesis. Study Design/Materials and Methods In the standard hamster cheek pouch model for oral carcinogenesis (n = 36), in vivo OCT was used to image epithelial and sub‐epithelial change. OCT‐ and histopathology‐based diagnoses on a scale of 0 (healthy) to 6 (squamous cell carcinoma, SCC) were performed at all stages throughout carcinogenesis by two blinded investigators. Results Epithelial, sub‐epithelial structures were clearly discernible using OCT. OCT diagnosis agreed with the histopathological gold standard in 80% of readings. Conclusion In vivo OCT demonstrates excellent potential as a diagnostic tool in the oral cavity. Lasers Surg. Med. 35:269–275, 2004. © 2004 Wiley‐Liss, Inc.
Tập 35 Số 4 - Trang 269-275 - 2004
A split‐face study of intense pulsed light on photoaging skin in Chinese population Abstract Background and Objectives Intense pulsed light (IPL) is regarded as the gold standard of nonablative photorejuvenation. Yet there is still a need to observe its efficacy and safety on dark skin using a split‐face module. Study Design/Materials and Methods Twenty‐four Chinese women with photoaging were enrolled in this study. Patients were randomized to receive four IPL treatments at 3‐ to 4‐week intervals on one side of face, with the other side spared as control. Changes of photoaging were evaluated using a global evaluation, an overall self‐assessment, a Mexameter and a Corneometer. Skin biopsies were taken after four sessions of treatment on one side of face. The melanocyte density and the contents of melanin, collagen fibers, and elastic fibers were stained and used to evaluate the improvement on dyschromia and other signs of photoaging. Results The global scores of photoaging on treated side decreased significantly from 3.02 to 1.22, while it remained unchanged on the untreated side. Twenty‐one of 24 patients (87.5%) rated their improvement as excellent or good. The difference on the values of melanin index and erythema index on treated side were significantly larger than those on untreated side after the 1st session, the 4th session and at 3‐month follow‐up (P <0.05). The melanin contents were significantly decreased and the collagen fibers were obviously increased only on treated side (P <0.05). Adverse effects of treated side were limited to mild pain and transient erythema. Conclusion Using this split‐face module, IPL treatment is proved both clinically and histologically to be effective in treating photoaging skin in Chinese population. Adverse effects were minimal and acceptable. Lasers Surg. Med. 42:185–191, 2010. © 2010 Wiley‐Liss, Inc.
Tập 42 Số 2 - Trang 185-191 - 2010
Clinical and echographic analysis of photodynamic therapy using methylaminolevulinate as sensitizer in the treatment of photodamaged facial skin Abstract Background and Objective Photodynamic therapy (PDT) using aminolevulinic acid (ALA) has been previously investigated in the treatment of photodamaged skin. The aim was to assess efficacy and tolerability of methylaminolevulinate (MAL) as a substitute for ALA in PDT treatment of actinic keratosis (AK) and photoaging. Study Design/Materials and Methods Twenty patients with multiple (n = 137) AKs and severe photodamage of the face were treated. Metvix® (Galderma, France) was applied under occlusion for 3 hours before exposure to 37 J/cm2 of red light (Aklilite® CL 128, Photocure, Norway). Two treatments were given at monthly intervals. Results The clearance rate of AKs was 88.3%, and global score which we use to rate photoaging, mottled hyperpigmentation, fine lines, roughness, and sallowness of the skin showed improvement, but deep wrinkles, teleangiectasia, facial erythema, and sebaceous gland hypertrophy did not change. The treatments were well tolerated. High‐resolution echography showed an increase in skin thickness, pixels count and area, as well as a reduction of the subepidermal low‐echogenic band (SLEB) thickness. Conclusion MAL‐PDT is an effective treatment for multiple AKs. In addition, it improves clinical signs of photodamage of the surrounding skin. Lasers Surg. Med. 39:203–209, 2007. © 2007 Wiley‐Liss, Inc.
Tập 39 Số 3 - Trang 203-209 - 2007
Carbon dioxide laser‐assisted thyroarytenoid myomectomy Abstract CO2 laser‐assisted myomectomy of the thyroarytenoid muscle (TA) was carried out through a thyroplasty approach in ten la‐ryngeal specimens and the TA was examined histologically. Using the CO2 laser at super‐pulsed mode, the TA can be cut or resected using 3–5 W of laser power. There is good control of the depth and extent of TA resection. Histologically, there is little evidence of collateral injury, with sparing of vital surrounding vocal structures. The use of CO2 laser for TA resection offers better access and surgical hemostasis in an otherwise difficult surgical field. Laser‐assisted myomectomy may be a feasible alternative to current methods to treat spasmodic dysphonia.
Tập 10 Số 5 - Trang 438-443 - 1990