ABSTRACT
BACKGROUND: Laparoscopic colectomy is associated with less overall morbidity and improved survival for patients with colonic cancers. There are unfortunately limited clinical reports on laparoscopic abdominoperineal resection. We therefore designed this study to compare laparoscopic abdominoperineal resection with conventional open surgery, with emphasis on health-related issues from the patients' perspective in order to justify its role in the management of low rectal or anal canal tumours. METHODS: We carried out a non-randomized, prospective comparative study on a cohort of patients who underwent either laparoscopic or open abdominoperineal resection between March 1994 and December 2003. Patient demographics, tumour characteristics, operative morbidity and mortality, as well as overall survival were considered. The standard endpoints of last follow-up date and deaths were used. Data was analyzed according to intention-to-treat principle. RESULTS: A total of 102 patients were recruited: 31 patients underwent conventional open abdominoperineal resection (OAPR) and 71 patients were treated laparoscopically. Patient demographics, median follow-up period, as well as tumour characteristics were similar between groups. The median operating time was similar among groups (145 min in laparoscopic group vs. 156 min in open group; p=0.62). Patients in the laparoscopic group had significantly less blood loss (p=0.01) and fewer requirements for blood transfusion (p=0.01). Despite similar overall morbidity, the laparoscopic group had a reduced incidence of abdominal wound infections (p=0.01) and chest infections (p=0.01). Overall survival was significantly better in the laparoscopic group (p=0.01). CONCLUSIONS: Laparoscopic abdominoperineal resection confers definite health-related benefits the over open approach in terms of reduced septic complications and fewer requirements for blood transfusion. It should be considered the procedure of choice for patients with low rectal or anal canal tumour in whom sphincter excision proved inevitable.
Subject(s)
Colorectal Neoplasms/surgery , Digestive System Surgical Procedures/methods , Laparoscopy , Abdomen/surgery , Adult , Aged , Aged, 80 and over , Chi-Square Distribution , Female , Humans , Male , Middle Aged , Perineum/surgery , Prospective Studies , Statistics, Nonparametric , Survival Analysis , Treatment OutcomeABSTRACT
Stimulated resonance Raman scattering (SRRS) of Rhodamine 6G (R6G) has been observed in microdroplets. By increasing the R6G concentration and input-laser intensity, SRRS from R6G can be distinguished from the R6G lasing. SRRS can be further amplified by the lasing gain when the SRRS is near the peak of the lasing gain profile. When the R6G Raman emission is at wavelengths longer than the lasing envelope, SRRS can still be enhanced by seeding from residual R6G fluorescence.
ABSTRACT
Fluorescence seeding by dissolving a fluorescent dye in a liquid droplet enhances the stimulated Raman scattering of a weaker-gain Raman mode. With the dye fluorescence at the Stokes wavelength of the weaker-gain Raman mode, the weaker-gain Raman mode can now build up from the much stronger fluorescence instead of from the weaker spontaneous Raman scattering. With fluorescence seeding, the weaker-gain C-C-O Raman mode of ethanol can be observed at a much lower input-laser intensity and can be more intense than the stronger-gain C-H Raman mode.
ABSTRACT
Distortion, ejection, shattering, and propulsion of water and ethanol droplets containing Rhodamine 6G dye have been photographed at different time delays after initiation of a CO(2) laser pulse, whichcauses explosive vaporization of the droplets. We have developed a fluorescence imaging technique to photograph the liquid-phase portion of the ejected material and the parent droplet after irradiation by the CO(2) laser pulse.
