Perinephric abscess (presenting as abdominal pain) due to Listeria monocytogenes

The development of a haematoma after wide excision of breast tumours is not uncommon. Suction drainage is commonly used to prevent this but often increases the hospital stay and can create unsightly wounds. Argon beam coagulation is a new technique which permits large 'raw' areas to be coagulated with minimal tissue damage. We believe that this technique may reduce the development of haematomas and seromas after breast surgery. We present our initial results using argon beam coagulation after wide excision of breast tumours in 80 patients without suction drainage. One patient required a single aspiration of a seroma at the site of breast lump excision and none required surgical drainage. Argon beam coagulation appears a useful adjunct in breast surgery and may help reduce hospital stay.     

Assessment of the psychotropic activity of analogs of cholecystokinin tetrapeptide fragment]

BACKGROUND: Both dermabrasion and high-energy pulsed carbon dioxide (CO2) laser resurfacing can improve the appearance of surgical scars. Although the results of these two procedures have been compared using historical data, a prospective evaluation has never been performed in humans. OBJECTIVE: To prospectively compare the clinical effects of dermabrasion and high-energy pulsed CO2 laser resurfacing in the revision of surgical scars. METHODS: Facial surgical scars in four patients were prospectively revised using a split scar model. One half of the scar was dermabraded and the other half was resurfaced with the high-energy pulsed CO2 laser. Comparisons of the two treatment modalities were performed through clinical assessment, photographic evaluation, and textural analysis of the scars. RESULTS: The high-energy pulsed CO2 laser-resurfaced halves of the scar were bloodless with less postoperative crusting in comparison with the dermabraded halves. Reepithelialization time and degree and duration of postoperative erythema were similar for both treatment halves. Photographic evaluation and textural analysis showed comparable improvement in the clinical appearance and surface texture of the scars with both treatment modalities. CONCLUSIONS: Both the high-energy pulsed CO2 laser and dermabrasion can achieve comparable clinical improvement in the revision of surgical scars. The high-energy pulsed CO2 laser offers the advantage of a bloodless field and a more precise method of tissue ablation. Postoperative erythema, however, is an expected finding with both treatment modalities.     

Instrumentation and techniques for carbon dioxide lasers in equine general surgery

The carbon dioxide laser has become an important surgical instrument in human and veterinary medicine. The unique properties of this laser make it the instrument of choice for precise incision, coagulation, and vaporization of tissue at the body surface with minimal morbidity to the patient. This article describes the instrumentation and techniques used to perform a variety of equine general surgical procedures with the carbon dioxide laser. The benefits of surgery using the carbon dioxide laser include precise dissection with minimal trauma to adjacent tissues, good hemostasis, and the ability of the laser beam's thermal properties to kill bacteria or tumor cells in the operative field.     

Laser applications in inner ear surgery

Argon and carbon dioxide lasers can cause heat shrinkage of the membranous labyrinth without injury to hearing. The argon laser can penetrate the membranous labyrinth and cause destruction of targeted vestibula special sensory epithelium also without injury to hearing. Consequently, these lasers have been used successfully in two treatment techniques for benign paroxysmal positional vertigo, which are discussed in detail. The early techniques for laser assisted resection of the pars superior portion of the inner ear with hearing preservation are discussed.     

Haemostasis after partial hepatectomy using argon beam coagulation

The argon beam coagulator is a new device for haemostasis during and after surgery on parenchymatous organs. No data are available on its efficacy and tissue effect following hepatic resection. Blood loss, the time needed to achieve adequate haemostasis and histological findings after liver resection were assessed in 12 pigs using argon beam coagulation or suture ligation only, the mattress suture technique and tissue glue application. The treatment was randomly assigned to each of the four liver lobes in each pig. Median blood loss following argon beam coagulation was 13 (range 2-47) ml and after simple suture ligation 55 (range 2-260) ml (P < 0.02). The median time needed for adequate haemostasis following argon beam coagulation was 3 (range 2-7) min versus 14 (range 2-48) min in the control group (P < 0.005). There was no difference between argon beam coagulation and tissue glue, which were both superior to the use of mattress sutures. Argon beam coagulation resulted in less tissue damage than tissue glue or mattress suturing. The argon beam coagulator is an efficient device for achieving haemostasis following partial hepatectomy in the pig. It causes only a moderate tissue reaction.     

Feasibility of collecting disease reports from relatives for genetic epidemiologic investigations

BACKGROUND: For many years, the treatment of facial wrinkles has been performed exclusively by dermabrasion, chemical peeling, or surgical face lifting. However, the recently introduced carbon dioxide lasers which emit ultrashort coherent light beams enable the cosmetic surgeon to ablate superficial epidemic layers with absent or very limited side effects. The purpose of this paper is to compare laser skin resurfacing with classical face lifting and discuss the potentials and limitations of each method. METHODS AND PATIENTS: Three patients suffering from facial wrinkles on photoaged skin were treated with the ultrapulsed CO2 laser (UltraPulse 5000 C; wavelength 10,600 nm, pulse duration 0.6 to 0.9 ms, maximum pulse energy 500 mJ). This laser guarantees vaporization of very thin superficial skin layers without scarring and with minimizing lateral thermal injury due to extreme short pulse duration. A special handpiece (CPG) permits an exact approach and a bloodless ablation of relatively large areas of facial skin. The fourth patient underwent a surgical face lift due to the depth of wrinkles. RESULTS: Excellent cosmetic results were achieved in all three patients with superficial wrinkles who were treated by laser skin resurfacing. When treating deeper wrinkles, e.g., glabella or nasolabial fold, the surgical face lift is the preferred method. CONCLUSION: Ultrapulsed CO2 laser treatment expands the therapeutic options for superficial facial wrinkles, especially for perioral, periorbital, forehead, and cheeks wrinkles. It proves to be a safe and effective method with very limited if any side effects. Nevertheless, deeper wrinkles are still a domain of the classical face lift. The combination of both methods may improve the overall outcome in the future.     

Gorlin's syndrome: the role of the carbon dioxide laser in patient management

The treatment of multiple basal cell carcinomas in patients with Gorlin's syndrome presents a therapeutic challenge. The carbon dioxide laser presents a unique treatment option due to increased surgical speed, a bloodless operating field, reduced postoperative pain and discomfort, and acceptable scars. Six patients with Gorlin's syndrome have been treated with the carbon dioxide laser. Between 14 and 110 lesions were treated in one session under local anesthesia. Pre- and postlaser biopsies of the lesions confirm complete eradication of the tumors. Mean follow-up is 20 months. No local recurrence has been observed.     

Corneal neovascularization treated with argon laser

The argon laser set at 50 mum, 100-150 mW, o-2 s occluded corneal blood vessels in pigmented Dutch rabbits provided the corneal responsible for inducing vascularization was inactive. After arterial treatment with the argon laser retrograde flow in untreated veins was demonstrated by fluorescein angiography. Therefore all corneal new vessels should be treated, not just arteries. Minimal iris damage complicated the laser therapy, but this was not thought necessarily to contraindicate the use of the argon laser to treat corneal blood vessels in man. The iris damage was associated with outpouring of aqueous from the ciliary processes, and it took up to a week for the blood-aqueous barrier to return to its normal state.     

Q-switched ruby laser treatment of mucocutaneous melanosis associated with Peutz-Jeghers syndrome

Peutz-Jeghers syndrome is an eponym for circumscribed mucocutaneous melanosis in association with gastrointestinal polyposis. Irregular pigmented macules of varying size and color can be found on the perioral skin, lip vermillion border, buccal mucosa, palate, and tongue. Previous treatments, such as surgical excision, cryosurgery, electrodesiccation, dermabrasion, and carbon dioxide or argon laser ablation commonly result in incomplete removal, scarring, or changes in normal pigmentation. The Q-switched ruby laser used at 694 nm, a wavelength well absorbed by melanin relative to other optically absorbing structures in skin, causes highly selective destruction of pigment-laden cells. In addition, the 20-nanosecond pulse duration produced by this laser approximates the thermal relaxation time for melanosomes, thereby confining the energy to the target. The Q-switched ruby laser produces clinically significant fading of mucocutaneous melanosis in association with Peutz-Jeghers syndrome without complications often seen with other therapeutic modalities.     

Circadian entrainment and phase shifting in mammals with melatonin

BACKGROUND: Diathermy procedures are indispensable in interventional endoscopy. Argon beam coagulation is an innovative no-touch electrocoagulation technique in which high-frequency alternating current is delivered to the tissue through ionized argon gas. METHOD AND PATIENTS: Before clinical application, we conducted in-vitro studies to investigate the depth and diameters of tissue coagulation in fresh operative specimens from the stomach, small intestine and colon. Five different power/gas flow settings between 40 and 155 W and 2 and 7 l/min were used. The impact time (1-10s) and the incident angle of the probe (45 degrees and 90 degrees) were also varied. The maximum depth of necrosis was 2.4 mm, the maximum diameter 1.1 cm. No perforation occurred even in critical areas such as the colon and duodenum. We therefore performed argon beam coagulation in 66 consecutive patients. Two power/gas flow settings of 40 and 70 W and 2 and 3 l/min, respectively, were used. The impact time and incident angle were varied individually. RESULTS: In 49 of the 50 patients with oozing haemorrhage from angiodysplastic lesions, polypectomy sites, erosions or ulcers or oozing of blood due to vascular penetration by tumours, definitive haemostasis was achieved in one to two sessions. In all 11 patients with residual sessile adenoma tissue, complete removal was possible. Oesophageal patency was restored in all five patients with stenosing tumours. In one patient with angiodysplasia of the caecal pole, an asymptomatic accumulation of gas in the submucosa was observed which resolved spontaneously. In two patients with extensive oesophageal carcinoma, there was a transitory--also asymptomatic--accumulation of gas in the mediastinum and peritoneal cavity but no evidence of perforation. CONCLUSION: Argon plasma electrocoagulation is an effective and relatively low-cost alternative to laser therapy in gastrointestinal endoscopy.     

Treatment of superficial basal cell carcinoma and squamous cell carcinoma in situ with a high-energy pulsed carbon dioxide laser

BACKGROUND: High-energy pulsed carbon dioxide (CO2) lasers have been used extensively to resurface wrinkled and photodamaged skin with a low risk of scarring. Results of histological studies demonstrate precise ablation depths in treated skin with minimal thermal damage to underlying tissue. Our objective was to determine if a pulsed CO2 laser could effectively ablate superficial malignant cutaneous neoplasms (superficial multifocal basal cell carcinoma [BCC] and squamous cell carcinoma [SCC] in situ). OBSERVATIONS: Thirty superficial neoplasms (17 BCCs and 13 SCCs) and their surrounding 3-mm margins were treated with either 2 or 3 passes of a pulsed CO2 laser (500 mJ, 2-4 W) using a 3-mm collimated handpiece. The treated areas were subsequently excised and evaluated histologically by serial sectioning at 5-micron intervals for residual tumor at the deep and lateral margins. Average patient age was greater for those with SCCs than for those with BCCs (76.5 vs 56.7 years; P = .001). The average tumor thickness of SCC in situ was significantly greater than that of superficial BCC (0.57 vs 0.34 mm; P = .01). All (9 of 9 patients) BCCs were completely ablated with 3 passes, and residual tumor in the deep margins was seen in 5 of 8 patients treated with 2 passes of the pulsed CO2 laser (P = .005). Incomplete vaporization of the SCC depth was seen in 3 of 7 patients treated with 3 passes and in 2 of 6 patients treated with 2 passes. Those SCCs incompletely treated were significantly thicker than those completely ablated (0.65 vs 0.41 mm; P = .01). Positive lateral margins were seen in 1 BCC and 3 SCC specimens. CONCLUSIONS: Pulsed CO2 laser treatment can be effective in ablating superficial BCC. Treatment of the neoplasm and a minimum of 4-mm margins with 3 passes (500 mJ, 2-4 W) is recommended for complete vaporization using this laser system. Because 3 passes did not completely ablate all SCC in situ, use of this modality alone is not recommended for treatment of thick or keratotic lesions. No direct comparison of efficacy can be made with other destructive modalities that have not been evaluated with comparably sensitive histological techniques. Further study is needed to establish any cosmetic advantage of pulsed CO2 lasers over other destructive modalities for treatment of superficial malignant neoplasms and long-term cure rates.     

When life is ending, there is the right to death with dignity

BACKGROUND: This report summarizes an institutional review board-approved 6-month study with the NovaPulse carbon dioxide (CO2) laser utilizing the NovaScan handpiece in facial skin resurfacing applications. OBJECTIVE: This study comprised the initial clinical evaluation (pre-FDA approval) of this device. METHODS: A total of 54 patients underwent 56 laser procedures: 36 full face and 20 regional procedures. RESULTS: Following healing, there was a 91% satisfaction rate. The mean laser-on times were: full face, 27 min; perioral, 7 min; periorbital, 3 min; glabellar, 2.5 min; scar, 5 min; and epidermal lesions, 6 min. CONCLUSIONS: The NovaScan CO2 laser handpiece is a safe tool for skin resurfacing. In its initial use over a 6-month period there were no device-related complications.     

Effects of various laser types and beam transmission methods on female organ tissue in the pig: an in vitro study

The purpose of this in vitro study was to investigate and compare effects of various laser types (CO2, Argon, Erbium:YAG, Erbium:YSGG, and Holmium:YAG) and laser beam transmission methods (optical lens and flexible fiber) on ovarian and uterine tissue of the pig. The Erbium laser radiation was transmitted through Zirconium fluoride fibers (ZrF4). To circumvent the low mechanical stability of these fibers, we developed a special microlens system, which refocuses the radiation and protects the distal end from damage. Tissue lesions were performed with 1 and 5 joule. Histologic analysis of acute Er:YAG laser lesions reveal precise cutting effects with a minimal thermal damage zone of 40 microns and a high damage resistance of the fiber microlens systems. The extent of thermal damage caused by the Erbium:YSGG and CO2 laser is about two times larger, whereas the Argon and Holmium laser tissue lesions show a damage of the surrounding tissue of 200-300 microns. This study suggests that for precise cutting and coagulation, Erbium and Holmium lasers transmitted via our modified fiber tip may render the use of these lasers possible in a wide range of laparoscopic surgery applications.     

Multicenter clinical experience using an erbium:YAG laser for vitreoretinal surgery

PURPOSE: To evaluate the advantages, disadvantages, safety, complications, and surgical applicability of an erbium:YAG laser system for maneuvers in vitreoretinal surgery. METHODS: A prospective, consecutive trial of 68 eyes in 66 patients undergoing vitreoretinal surgery in which an erbium:YAG laser with graduated output from 0.2 to 5.0 mJ per pulse, repetition rate of 2 to 30 Hz, and equipped with a flexible fiber optic and interchangeable 20-gauge intraocular fiber optic endoprobes was used to perform specific maneuvers, including transection, incision, and ablation of membranes, retinotomy, vessel coagulation, iridectomy, and lens tissue ablation. The patients were treated in five centers in contemporary vitreoretinal surgical settings for surgical indications, including proliferative diabetic retinopathy, proliferative vitreoretinopathy, epiretinal membrane, and retinopathy of prematurity. RESULTS: One hundred seventy-four maneuvers were performed with an overall surgical efficacy rating of excellent or good in 84% of maneuvers, ranging from a high of 100% for subretinal membrane transection to a low of 25% for coagulation of blood vessels. Complications included retinal break or photocoagulative injury in 5% of epiretinal membrane incisions, minor bleeding from transected retinal vessels during 29% of retinotomies, and intraocular lens damage during two posterior capsulotomies. The most significant limitation was the cautious pace used during maneuvers near the retinal surface. CONCLUSION: The erbium:YAG laser is capable of versatile new approaches offering precise tissue cutting and ablation in vitreoretinal surgical maneuvers with a high degree of safety. The main limitation encountered was the slow speed of certain critical maneuvers near the retina.     

Carbon dioxide laser for laparoscopic enterocele repair

The use of the carbon dioxide (CO2) laser for laparoscopic enterocele repair was evaluated in four women with an enterocele as the only pathology. Three women had a large enterocele after earlier hysterectomy, and one young woman had a congenital enterocele. The technique consists of vaporizing the peritoneum of the enterocele; however, it is important first to delineate carefully the lesion's circumference because of the strong retraction during vaporization. Subsequently, a posterior culdotomy is performed taking care to restore the horizontal position of the upper vaginal axis by shortening the uterosacral ligaments, which are sutured together on the midline and the posterior vaginal wall. The (CO2) laser has the advantage that the superficial vaporization it produces is rapid (<5 min), safe, and completely bloodless. The shrinking during vaporization facilitates subsequent repair. Postoperative morbidity and recovery were uneventful for all patients. The (CO2) laser seems to have some advantages over sharp endoscopic resection of enteroceles. The relative simplicity of technique and the low postoperative morbidity suggest that endoscopy could become routine in pelvic floor surgery, improving diagnosis and complementing vaginal surgery while avoiding laparotomy.     

A-scsan sonography for the measurement of the thickness of the bladder wall

The A-mode ultrasonography is especially qualified for measuring tissue thickness. By using high frequencies (8--10 MHz) upper layers can be measured with an accuracy of approximately 0.15 mm. This accuracy in measurement is required in connexion with optimization of dose during therapy of urinary bladder tumors by way of the Neodymium-YAG laser. The newly developed 8 MHz-endo-transducer makes possible intravesical measurement of bladder-wall thickness under cystoscopoic view. This method presents itself as a new opportunity for staging urinary bladder tumors.     

Intra-operative laser-induced photodynamic therapy in the treatment of experimental hepatic tumours

OBJECTIVE: To examine the effect of photodynamic therapy (PDT) on experimental liver tumours in rats. DESIGN: An experimental liver tumour model was used. Each of a group of rats had two tumours simultaneously inoculated into its liver. The tumour located in the left hepatic lobe was used for PDT, and the other one, in the median lobe, as a control. The haem precursor delta-amino laevulinic acid (ALA), at a dose of 30 mg/kg body weight, was injected 60 min before laser irradiation. Rats in group I received ALA through a femoral vein. Those in group II received ALA through the portal vein. Group III had an injection of ALA solution through the portal vein plus hepatic inflow occlusion. Three and 6 days after the treatment, the rats were killed, and the tumours were measured, and ultrastructural changes were examined using scanning electron microscopy. SETTING: Lund University Medical Laser Centre, Lund, Sweden. RESULTS: The mean tumour volume of the treated tumours increased by factors of 1.9, 1.5 and 1.7 in groups I, II and III, respectively, compared with the pretreatment baseline value. However, the mean tumour volume in the control tumours increased by factors of 9.5, 4.3 and 4.8 in the respective groups. Under the light microscope, marked necrosis of the treated tumour and the surrounding liver tissue was observed. Scanning electron microscopy revealed heavy damage to the cells and vessels in the treated tumour. CONCLUSION: PDT with ALA is an effective treatment modality for rat liver tumours.     

Laser welding of fascial grafts and its potential application in tympanoplasty: an animal model

This study evaluates the welding effect of argon laser on fascial grafts and its potential application in tympanoplasty. An animal model was designed so that surgically induced perforations of the lumbar fascia of the animals were grafted in an underlay fashion. Each graft was "spot welded" around the circumference of the perforation using a hand-held argon laser. Various lasing parameters were used on different grafts. Control perforations were grafted but not welded. A total of 96 perforations was studied. Weld sites were evaluated both histologically and by tensile strength measurement at the end of surgery, and at 7, 14, and 21 days postoperatively. Comparison with controls showed a higher tensile strength for welded grafts, which was most significant in the early postoperative period (p < 0.001). Histologically, it seems that the basic mechanism of fascial welding involves liquification and denaturation of extravasated proteins at the weld sites. Correlation between the extent of thermal damage on the tissues and the various lasing parameters is described. Based on the well-documented safety of argon laser in otologic surgery, and the successful welding of fascial grafts in this study, argon laser may prove beneficial in welding temporalis fascia grafts in tympanoplasty.     

Chordomas of the skull base. Radiologic and clinical evaluation

Chordomas are uncommon skull base tumors, which are locally agressive and are usually not amenable to complete surgical resection. Proton beam irradiation, following surgery, is the preferred treatment modality. For diagnosis and determination of tumor site and extension, CT and MR imaging are the imaging modalities of choice. CT delineates bone destruction and the presence of calcifications and destroyed bone optimally. MR imaging is the modality of choice for better definition of the tumor margin from brain and other soft tissue structures (pharynx) and visualization of blood vessels. The signal intensities and enhancement pattern fail to differentiate chordoma from chondroid chordoma or chondrosarcoma. Chordomas arise from the clivus and therefore are located more centrally, whereas the majority of chondrosarcomas originate in the petroclival fissure and occur more laterally, although occasional overlap occurs in about one third of cases. Immunohistochemical methods allow differentiation of pure chordoma from chondroid chordoma and chondrosarcoma. Chordomas have a lower local control rate than chondrosarcomas.     

Identification of photoacoustic transients during pulsed laser ablation of the human temporal bone: an experimental model

Laser ablation of hard tissues during neurotologic operations has been accomplished with continuous-wave (CW) lasers in the visible and midinfrared spectrum. The mechanism of ablation at these wavelengths is secondary to photothermal-induced tissue destruction. As a result, significant thermal damage to surrounding tissue may occur. Pulsed ultraviolet (UV) lasers have been suggested as an alternative to the argon, KTP-532, and CO2 lasers currently used in clinical practice. The pulse length of Excimer lasers are considerably shorter than the thermal diffusion time of bone tissue, and as a consequence thermal injury is minimal. This makes pulsed lasers an attractive tool for tissue ablation in the ear: in essence a "cold knife." However, the short pulse width of Excimer lasers (typically 10-150 ns) can create large thermoelastic stresses in the ablation specimen. This study identifies the presence of these photoacoustic waves during the Excimer laser treatment of the cadaveric human temporal bone. A XeCl (lambda = 308 nm, tau p = 12 ns) excimer laser was used to ablate hard tissue surrounding the oval window and facial ridge with energies of 75, 45, 25, and 12 mJ/pulse. Spot size was estimated to be 0.5 mm2. Custom high-frequency polyvinyldifluoride (PVDF) piezoelectric film transducers were fabricated and attached to the promontory, round window niche, and facial ridges. The signals were amplified using a low-noise preamplifier and recorded on a digitizing oscilloscope. Photoacoustic waves were clearly identified. Notably, large acoustic waves were measured on the promontory and on both sides of the facial ridge. The implications and clinical relevance of these findings is discussed and compared to findings obtained from a model system.