Fourier transform spectrometer based on high-repetition-rate mid-infrared supercontinuum sources for trace gas detection.

We present a fast-scanning Fourier transform spectrometer (FTS) in combination with high-repetition-rate mid-infrared supercontinuum sources, covering a wavelength range of 2-10.5 µm. We demonstrate the performance of the spectrometer for trace gas detection and compare various detection methods: baseband detection with a single photodetector, baseband balanced detection, and synchronous demodulation at the repetition rate of the supercontinuum source. The FTS uses off-the-shelf optical components and provides a minimum spectral resolution of 750 MHz. It achieves a noise equivalent absorption sensitivity of ∼10-6 cm-1 Hz-1/2 per spectral element, by using a 31.2 m multipass absorption cell.

Effect of nordihydroguaiaretic acid on spermatogenesis and fertility in rats.

Nordihydroguaiaretic acid (NDGA) is a naturally occurring lignan with potent antioxidant activity. Currently, it is in clinical trials as anticancer agent. As there is no earlier report on the effect of NDGA on spermatogenesis and fertility, this study was designed to investigate this aspect. Administration of NDGA to rats for 60 days produced degenerative changes in testis but had no effect on sperm DNA integrity test and androgen receptor expression. Ultrastructural studies revealed loss of integrity of cells in seminiferous tubules, vacuolation and presence of apoptotic bodies. Derangement of the outer dense fibres was noted in some sperm flagella. Acrosome formation appears to be normal. About 13.7% of epididymal spermatozoa had deformations like short tail or rounded head. This may explain the lower fertility index in NDGA-treated group. No external deformations in newborns were noted. In conclusion, NDGA may have adverse effects on spermatogenesis.

Conversion in laparoscopic colorectal surgery: Are short-term outcomes worse than with open surgery?

BACKGROUND: The aim of the present study was to compare the perioperative outcomes in patients who underwent planned open colectomy to those who were converted to an open. METHODS: All patients who underwent elective colectomy were identified from the American College of Surgeons National Surgical Quality Improvement Program using procedure-targeted database (2012-2014). Patients were divided into two groups: open (planned) versus converted. Perioperative outcomes were compared. A logistic regression model was used to calculate the propensity of unplanned conversion as opposed to open surgery. RESULTS: There were 21,437 patients; 17,366 (81.0%) in the open group and 4071 (19.0%) in the converted group. Operative time was longer in the converted group (212 ± 99 vs. 182 ± 111 min, p < 0.001), and hospital stay was longer in the open group (10.5 ± 9.3 vs. 8.7 ± 7.7 days, p < 0.001). Difference in morbidity rate (37.6% open vs. 34.5% converted, p < 0.001) was no longer significant once confounders were adjusted. Specific complications were similar except for superficial surgical site infection (SSI) rate, which was significantly lower in open group (odds ratio 0.87, 95% confidence interval 0.76-0.97, p = 0.010). CONCLUSIONS: The current study showed that conversion of laparoscopic colectomy to an open approach was associated with slight increase in superficial SSI rate but shorter hospital stay compared to planned open.

Predictors of wound dehiscence and its impact on mortality after abdominoperineal resection: data from the National Surgical Quality Improvement Program.

BACKGROUND: Wound dehiscence is a known complication following abdominoperineal resection (APR) and can have a negative impact on recovery and outcome. The aim of this study was to determine the predictors of post-APR 30-day abdominal and/or perineal wound dehiscence, readmission, and reoperation, and to assess the impact of wound dehiscence on 30-day mortality. METHODS: All patients undergoing APR between 2005 and 2012 were analyzed using the American College of Surgeons National Surgical Quality Improvement Program. RESULTS: There were 5161 patients [male = 3076 (59.6 %)] with a mean age of 61.9 ± 14.3 years. Mean body mass index was 27.4 ± 6.6 kg/m(2). The most common indication for surgery was rectal cancer (79.1 %), followed by inflammatory bowel disease (8.2 %). The overall rate of wound dehiscence was 2.7 % (n = 141). Older age (p = 0.013), baseline dyspnea (p = 0.043), smoking history (p = 0.009), and muscle flap creation (p ≤ 0.001) were independently associated with the risk of dehiscence. No association was observed between omental flap creation and dehiscence risk (p = 0.47). The 30-day readmission rate (15.6 vs. 5.6 %, p ≤ 0.001) and need for reoperation (39 vs. 6.6 %, p ≤ 0.001) were significantly higher in patients who experienced dehiscence. Dehiscence was an independent risk factor for 30-day mortality [OR = 2.69 (1.02-7.08), p = 0.045)]. CONCLUSIONS: Older age, baseline dyspnea, smoking, and the use of muscle flap were associated with higher risk of wound dehiscence following APR. Patients with wound dehiscence had a higher rate of readmission and need for reoperation, and an increased risk of 30-day mortality.

Tandem vaginoscopy with colonoscopy: a diagnostic technique for the assessment of colovaginal fistula.

AIM: Colovaginal fistula (CVF) has a negative impact on quality of life. Identifying the fistula track is a critical step in its management. In a subset of patients, localizing the fistula preoperatively can be difficult. The purpose of this report is to describe the technique and results of tandem vaginoscopy with colonoscopy (TVC). METHOD: A retrospective analysis was conducted of all patients referred to a tertiary centre with symptoms suggestive of CVF but no prior successful localization of a fistula. TVC was performed by one colorectal surgeon in the endoscopy suite under intravenous sedation. RESULTS: Between 2003 and 2013, 18 patients (median age 58 years) underwent TVC. CVF was ruled out in three patients. In the remaining 15 patients, TVC documented the fistula in 13. In eight cases a wire was passed through the fistulous track from the vagina to the colon, in three the track was large enough to be traversed with the endoscope and in two a fistulous opening was noted on the vaginal side but passage of a wire to localize the opening on the colonic side was not possible due to extensive scarring. No TVC-related complications were recorded. The sensitivity, specificity, positive predictive value and negative predictive value for TVC in detecting CVF were 86.7%, 100%, 100% and 60%, respectively. CONCLUSION: TVC is a useful technique that can localize the fistulous track in most patients with CVF.

Long-term outcomes after circular stapled hemorrhoidopexy versus Ferguson hemorrhoidectomy.

BACKGROUND: We aimed to compare long-term outcomes and quality of life in patients undergoing circular stapled hemorrhoidopexy to those who had Ferguson hemorrhoidectomy. METHODS: Patients who underwent Ferguson hemorrhoidectomy and circular stapled hemorrhoidopexy between 2000 and 2010 were reviewed. Long-term follow-up was assessed with questionnaires. RESULTS: Two hundred seventeen patients completed the questionnaires. Mean follow-up was longer in the Ferguson hemorrhoidectomy subgroups (7.7 ± 3.4 vs. 6.3 ± 2.9 years, p = 0.003). Long-term need for additional surgical or medical treatment was similar in the Ferguson hemorrhoidectomy and circular stapled hemorrhoidopexy groups (3 vs. 5%, p = 0.47 and 3% in both groups, p > 0.99, respectively). Eighty-one percentage of Ferguson hemorrhoidectomy and 83% of circular stapled hemorrhoidopexy patients stated that they would undergo hemorrhoid surgery again if needed (p = 0.86). The symptoms were greatly improved in the majority of patients (p = 0.06), and there was no difference between the groups as regards long-term anorectal pain (p = 0.16). The Cleveland global quality of life, fecal incontinence severity index, and fecal incontinence quality of life scores were similar (p > 0.05). CONCLUSIONS: This is one of the longest follow-up studies comparing the outcomes after circular stapled hemorrhoidopexy and Ferguson hemorrhoidectomy. Patient satisfaction, resolution of symptoms, quality of life, and functional outcome appear similar after circular stapled hemorrhoidopexy and Ferguson hemorrhoidectomy in long term.

Outcome of colonic fistula surgery in the modern surgical era.

BACKGROUND: Various conditions lead to the development of colonic fistulas. Contemporary surgical data is scarce and it is unclear whether advances in surgical care have impacted outcome. The aim of the present study was to review the short- and long-term outcome of patients treated surgically for colonic fistula over an 8-year period at a tertiary institution. METHODS: A retrospective review was performed, focusing on the type of operative interventions, short- and long-term complications, length of hospital stay, readmission rate, mortality rate, and fistula recurrence. RESULTS: Forty-five patients were treated for colonic fistula. The most common etiology was diverticulitis (74%). Fistula type was colovesical (58%), colocutaneous (18%) and colovaginal (15%). Laparoscopic resection was performed in 42% of cases. An intraoperative complication occurred in 4%. A primary anastomosis was performed in 96% of patients and 10 (23%) had a temporary stoma. Median length of hospital stay was 6 days. Postoperative complications were common (47%) and wound infection was noted in 20% of patients. The readmission rate was 29% and the 90-day mortality was 4%. All patients healed their fistula with no recurrences noted during a median follow-up of 37 months. CONCLUSIONS: Surgical intervention healed the majority of patients with colonic fistula. However postoperative complications were common and readmission occurred in one-third of the cases. Laparoscopic excision was feasible in nearly half of the patients.

Triage of patients with acute diverticulitis: are some inpatients candidates for outpatient treatment?

AIM: Current recommendations regarding the triage of patients with acute diverticulitis for inpatient or outpatient treatment are vague. We hypothesized that a significant number of patients treated as an inpatient could be managed as an outpatient. METHOD: A retrospective cohort study was carried out of 639 patients admitted for a first episode of diverticulitis. The diagnosis of acute diverticulitis was confirmed by computed tomography (CT). The endpoints included length of stay, need for surgery, percutaneous drainage and mortality. Patients were considered to have had a minimal hospitalization, defined as survival to discharge without needing a procedure, hospitalization of ≤ 3 days and no readmission for diverticulitis within 30 days after discharge. RESULTS: Of 639 patients, 368 (57.6%) had a minimal hospitalization. Female gender and CT scan findings of free air/fluid were negatively associated with the likelihood of minimal hospitalization. The presence of an abscess < 3 cm and stranding on CT did not predict the need for a higher level of care. Despite the statistical significance of several patient-level predictors, the model did not identify patients likely to need only minimal hospitalization. CONCLUSION: Most patients admitted with acute diverticulitis are discharged after minimal hospitalization. Free air/liquid in a patient admitted for acute diverticulitis indicates a more severe clinical course.

Laparoscopic right hemicolectomy.

Over the past 20 years, laparoscopic colectomy has become a well-established technique in the surgical armamentarium of colorectal operations, with proven reductions in postoperative pain, time to return of bowel function, and length of hospital stay. After early concerns over its oncologic effects, large prospective, multicenter trials have proven its safety in colorectal adenocarcinoma, with equivalence in nodal harvest, recurrence rates, disease-free survival, and overall survival. Laparoscopic right hemicolectomy in particular is a relatively accessible technique which may be performed by a single surgeon and an assistant/camera operator; this operation serves as an excellent method to develop laparoscopic skills for more complicated colorectal procedures. In this article, we describe the technical aspects of our approach to laparoscopic right hemicolectomy, which utilizes a medial-to-lateral, no-touch technique and either an intracorporeal or extracorporeal anastomosis.

Squamous cell carcinoma of the rectum: a single institution experience.

BACKGROUND: Squamous cell carcinoma (SCC) of the rectum is a rare disorder. There is currently no effective method as to how best treat patients with this condition. The purpose of this study was to review a single tertiary institution's experience. METHODS: A retrospective chart review was conducted of all patients who presented with documented SCC of the rectum over a 10-year period (2000-2010). During the study period, all patients were offered chemoradiation as an initial treatment modality [a fluorouracil (5-FU)-based regimen in conjunction with mitomycin or cisplatin]. RESULTS: Six patients presented with primary rectal SCC. Mean patient age was 60 years. The majority of patients were female (83 %). The most common presenting symptom was rectal bleeding (67 %). The mean distance from the inferior tumor margin to the anal verge was 6 cm. Two patients (33 %) presented with stage II disease, and 4 (67 %) were stage III. Five patients (83 %) received chemoradiation therapy initially, and 1 patient underwent abdominoperineal resection after refusing chemoradiation. Two additional patients (33 %) underwent salvage surgery. During a mean follow-up of 44 months, 4 patients (66 %) were alive without evidence of disease. CONCLUSIONS: Based on the results of this cases series, chemoradiation as an initial primary therapy appears to be beneficial for patients with primary SCC of the rectum. A 5-FU chemotherapy-based regimen in conjunction with fractionated radiotherapy appears to be effective for local control of the disease.

Outcome of components separation for contaminated complex abdominal wall defects.

BACKGROUND: Contaminated large abdominal wall defects can pose a formidable challenge to the surgeon. This study compared the outcome of components separation (CS) for complex ventral defects with or without contamination. METHODS: A retrospective review was conducted of all patients who underwent CS over an 8-year period. Pre-operative factors such as the presence/absence of contamination were analyzed for their effect on length of hospitalization, readmission rate, post-operative complications, re-intervention rate, and long-term recurrence. RESULTS: A total of 34 patients was analyzed. There were 18 males (53%) with a mean age of 57 years. Mean body mass index was 31 kg/m(2). Seventeen patients (50%) had prior repair (mean 2.1 repairs per patient, median 2). Mean size of abdominal defect was 255 cm(2). Out of the 34 patients, 13 had infected or contaminated defects, including 5 patients with infected mesh. Length of stay was longer in the contaminated group (11.1 vs 3.1 days, P < 0.01). A higher complication rate was noted in the setting of contamination (77 vs 38%, P = 0.03). During a mean follow-up of 47 months, no difference was noted in the re-intervention rate (38 vs 29%, P = 0.70) or long-term recurrence rate of the defect (8 vs 5%, P = 1.0) (contaminated vs non-contaminated group, respectively). CONCLUSIONS: CS is a good option for closure of large contaminated complex abdominal wall defects. Despite an increased risk of postoperative complications and longer hospitalization length, long-term outcomes are favorable.

Rectourethral fistula following laparoscopic radical prostatectomy.

PURPOSE: To review the outcome of rectourethral fistula sustained during laparoscopic radical prostatectomy. METHODS: A retrospective chart review of all cases managed at a tertiary referral center. Data abstracted included demographics, presenting symptoms, additional interventions, healing, and long-term functional outcome. RESULTS: Between 2004 and 2009, 10 patients were treated for rectourethral fistula following laparoscopic radical prostatectomy. Mean age was 60 years. Two patients were converted to open prostatectomy for primary repair of the rectal laceration without fecal diversion. The remaining 8 patients (80%) had unrecognized injury at the time of prostatectomy and presented postoperatively. Mean time from radical prostatectomy to presentation with fistula symptoms was 9.5 days. Seven patients (70%) required 1 or more operations to treat or control the symptoms of the rectourethral fistula (median 2.3, mean 2, range 1-4 operations). Three patients (30%) required colostomy within 1 month of radical prostatectomy due to severity of symptoms. Spontaneous healing of the fistula was noted in 6 patients (60%) following diversion (urinary ± fecal diversion), and a minority of patients (30%) required an operation to close the fistula. One patient (10%) required cystectomy for positive margins. During a mean follow-up of 27 months, no recurrent fistula was observed in any of the patients. All patients had normal anal continence, but the majority of patients were incontinent of urine. CONCLUSIONS: Patients who develop a rectourethral fistula following laparoscopic radical prostatectomy often require additional operations for symptoms control and/or healing of the fistula. Urinary continence is affected in the majority of patients.

Laparoscopic-assisted resection of bleeding jejunal leiomyoma.

Laparoscopic-assisted resection has shown remarkable improvements in the treatment of small bowel diseases, notably the leiomyomas. This case report documents the successful removal of a bleeding jejunal leiomyoma with the aid of laparoscopy. A 51-year-old man was admitted to the hospital twice within 3 months with melena. On the first admission, upper and lower gastrointestinal endoscopy were negative, and small bowel enema was inconclusive. On the second admission, Technetium-99 Red Blood Cells (Tm-99 RBC) scan showed dye extravasation (interpreted as from the left colon). Subsequent colonoscopy was normal, as was a barium enema. An elective superior mesenteric angiography revealed a benign-looking jejunal leiomyoma. Subsequent CT (intravenous contrast scan) revealed a 4.6 x 3.5 cm mass with neither extraluminal infiltration nor enlarged lymph nodes. The patient underwent successful laparoscopic-assisted resection of the leiomyoma and enjoyed an uneventful postoperative recovery. Subsequent histopathology confirmed the diagnosis. The diagnosis of small bowel leiomyoma is generally difficult because the conventional radiographic methods are unhelpful. These tumors are therefore best detected preoperatively with superior mesenteric angiography. Repeat of the noninvasive tests is strongly indicated if they are initially negative. Once discovered, small bowel leiomyoma should be resected to avoid catastrophic complications. Thereafter, it has an excellent prognosis. In this context, minimal-access surgery is a safe and approachable method to deal with such a problem.