Prospective experimental study of transrectal viscerotomy closure using transanal endoscopic suture vs. circular stapler: a step toward NOTES

BACKGROUND AND STUDY AIM

Endoluminal full-thickness closure of the rectal wall is critical in emerging procedures including endoscopic submucosal dissection and transrectal natural orifice transluminal endoscopic surgery (NOTES). This study aimed to compare manual suture using the transanal endoscopic operation platform (TEO; Karl Storz, Tüttlingen, Germany) with the end-to-end anastomosis hemorrhoid circular stapler (EEA; Covidien, Dublin, Ireland) for closure of the rectal viscerotomy during transrectal NOTES segmental colectomy.

MATERIALS AND METHODS

A total of 12 swine underwent transrectal hybrid NOTES partial colectomies. Animals were divided into two groups according to the viscerotomy closure technique: 1) TEO manual suture; 2) EEA circular stapler closure.

RESULTS

Mean (± SD) viscerotomy closure time was 67.5 ± 59.5 minutes and 31.5 ± 19.6 minutes for TEO and EEA, respectively. There was one conversion to laparoscopy in the TEO group and a misfiring in the EEA group that required a TEO salvage suture. There was one positive air-leak test in each group. Peritoneal fluid collected at the end of the procedure tested positive for bacterial contamination in all cases. A mild stenosis was present in 4 /6 viscerotomies (67 %) in the TEO group and in 1/6 (17 %) in the EEA group on endoscopic control. Inflammatory changes were mild in 3/5 (60 %) and 4/5 (80 %) viscerotomies in the TEO and EEA groups, respectively, whereas severe inflammation was found in 2/5 (TEO) and 1 /5 (EEA).

CONCLUSION

Transrectal viscerotomy closure using the EEA circular stapler technique is feasible, easy to perform, and histologically comparable to suture closure through a TEO platform. It may offer an attractive alternative for NOTES segmental colectomies and endoscopic resections.

Transanal extraction of the specimen during laparoscopic colectomy

AIM

To assess the current state of the art of transanal specimen extraction in colonic resections.

METHOD

A systematic literature search was conducted including the terms 'transrectal or transanal specimen extraction', 'Natural Orifice Specimen Extraction' and 'laparoscopic colectomy' for the period from 1955 to May 2011. Exclusion criteria were abdomino-perineal resections, pull-through technique, experimental studies and paediatric population.

RESULTS

Nineteen studies met the inclusion criteria, representing 154 patients. The overall postoperative complication rate was 10%. The risks of peritoneal contamination and sphincter dysfunction were evaluated by a single study of each.

CONCLUSION

Transanal extraction is a feasible option to minimize incisions in colorectal surgery.

Transvaginal specimen extraction in colorectal surgery: current state of the art

BACKGROUND

The expected benefit of transvaginal specimen extraction is reduced incision-related morbidity.

OBJECTIVES

A systematic review of transvaginal specimen extraction in colorectal surgery was carried out to assess this expectation.

SEARCH STRATEGY

The following keywords, in various combinations, were searched: NOSE (natural orifices specimen extraction), colorectal, colon surgery, transvaginal, right hemicolectomy, left hemicolectomy, low anterior resection, sigmoidectomy, ileocaecal resection, proctocolectomy, colon cancer, sigmoid diverticulitis and inflammatory bowel diseases.

SELECTION CRITERIA

SELECTION CRITERIA included large bowel resection with transvaginal specimen extraction, laparoscopic approach, human studies and English language. Exclusion criteria were experimental studies and laparotomic approach or local excision. All articles published up to February 2011 were included.

RESULTS

Twenty-three articles (including a total of 130 patients) fulfilled the search criteria. The primary diagnosis was colorectal cancer in 51% (67) of patients, endometriosis in 46% (60) of patients and other conditions in the remaining patients. A concurrent gynaecological procedure was performed in 17% (22) of patients. One case of conversion to laparotomy was reported. In two patients, transvaginal extraction failed. In left- and right-sided resections, the rate of severe complications was 3.7% and 2%, respectively. Two significant complications, one of pelvic seroma and one of rectovaginal fistula, were likely to have been related to transvaginal extraction. The degree of follow up was specified in only one study. Harvested nodes and negative margins were adequate and reported in 70% of oncological cases.

CONCLUSION

Vaginal extraction of a colorectal surgery specimen shows potential benefit, particularly when associated with a gynaecological procedure. Data from prospective randomized trials are needed to support the routine use of this technique.

Rituximab treatment in patients with active Graves' orbitopathy: effects on proinflammatory and humoral immune reactions

In active Graves' orbitopathy (GO), proinflammatory cytokines predominate. Circulating thyroid stimulating hormone (TSH)-receptor antibodies (TRAb) have been correlated with GO clinical activity and severity. In preliminary studies rituximab (RTX), an anti-CD 20 monoclonal antibody, has induced clinical improvement of active GO without a change in serum anti-thyroid antibodies. We have studied whether RTX in GO acts by affecting proinflammatory cytokines and thyroid and orbital-directed antibodies. Ten patients with GO were treated with RTX, administered twice intravenously (i.v.) (1000 mg) at days 1 and 15, and 20 with methylprednisolone, administered weekly i.v. (500 mg), for 16 weeks. Patients were studied before treatment, at B cell depletion and at 4, 8, 16, 20, 30 and 50 weeks. Peripheral lymphocytes, serum interleukin (sIL)-6, sIL-6r, chemokine (C-X-C motif) ligand 10 (CXCL10), TRAb and stimulating antibodies (TSAb) and autoantibodies against orbital calsequestrin, collagen XIII and flavoprotein subunit of succinate dehydrogenase (FP-SDH) were measured at baseline and after treatment. Serum IL-6 and sIL-6R concentrations did not change after RTX [P = not significant (n.s.)]. Serum CXCL10 increased after RTX at B cell depletion and at 30 weeks (P < 0·003). Serum TSAb did not change in relation to TRAb, nor did antibodies against orbital antigens (P = n.s.). In conclusion, this study shows that RTX in GO does not affect humoral reactions. The observed increase of serum CXCL10 concentrations at B cell depletion may result from cell lysis. We suggest that RTX may exert its effect in GO by inhibiting B cell antigen presentation.

Imaging single atoms using secondary electrons with an aberration-corrected electron microscope

Aberration correction has embarked on a new frontier in electron microscopy by overcoming the limitations of conventional round lenses, providing sub-angstrom-sized probes. However, improvement of spatial resolution using aberration correction so far has been limited to the use of transmitted electrons both in scanning and stationary mode, with an improvement of 20-40% (refs 3-8). In contrast, advances in the spatial resolution of scanning electron microscopes (SEMs), which are by far the most widely used instrument for surface imaging at the micrometre-nanometre scale, have been stagnant, despite several recent efforts. Here, we report a new SEM, with aberration correction, able to image single atoms by detecting electrons emerging from its surface as a result of interaction with the small probe. The spatial resolution achieved represents a fourfold improvement over the best-reported resolution in any SEM (refs 10-12). Furthermore, we can simultaneously probe the sample through its entire thickness with transmitted electrons. This ability is significant because it permits the selective visualization of bulk atoms and surface ones, beyond a traditional two-dimensional projection in transmission electron microscopy. It has the potential to revolutionize the field of microscopy and imaging, thereby opening the door to a wide range of applications, especially when combined with simultaneous nanoprobe spectroscopy.

Case report: successful use of hyperbaric oxygen therapy for a complete scalp degloving injury

We report a case of a complete scalp degloving injury in a 43-year-old previously healthy, tobacco-using female whose hair was caught in a tractor power take-off causing an instantaneous total scalping injury. Microsurgical replantation was started 4 hours after injury with the surgical procedure lasting 4 hours. Only the superficial temporal arteries were reanastomosed with no venous anastomosis possible. Hyperbaric oxygen (HBO2) treatment at 2.5 atmospheres absolute (ATA) for 90 minutes was administered immediately after surgery due to duskiness of the flap. Further HBO2 treatments were administered twice daily for seven days and then once daily for 30 days. Additionally, leech therapy was used for the first ten postoperative days. The patient's right auricle and most of the left auricle were completely lost. Despite the tenuous vascular inflow and initially absent venous drainage, at 3 month follow-up there was reepithelialization of her scalp except for an area of granulation tissue in the occipitoparietal area. At one year follow-up the area of granulation tissue was reduced, but there was no detectable hair growth or nerve function. We propose that HBO2 may facilitate tissue survival in scalp degloving injuries in the face of incomplete surgical revascularization.

Direct electron imaging in electron microscopy with monolithic active pixel sensors

A new imaging device for dynamic electron microscopy is in great demand. The detector should provide the experimenter with images having sufficient spatial resolution at high speed. Immunity to radiation damage, accumulated during exposures, is critical. Photographic film, a traditional medium, is not adequate for studies that require large volumes of data or rapid recording and charge coupled device (CCD) cameras have limited resolution, due to phosphor screen coupling. CCD chips are not suitable for direct recording due to their extreme sensitivity to radiation damage. This paper discusses characterization of monolithic active pixel sensors (MAPS) in a scanning electron microscope (SEM) as well as in a transmission electron microscope (TEM). The tested devices were two versions of the MIMOSA V (MV) chip. This 1M pixel device features pixel size of 17 x 17 microm(2) and was designed in a 0.6 microm CMOS process. The active layer for detection is a thin (less than 20 microm) epitaxial layer, limiting the broadening of the electron beam. The first version of the detector was a standard imager with electronics, passivation and interconnection layers on top of the active region; the second one was bottom-thinned, reaching the epitaxial layer from the bottom. The electron energies used range from a few keV to 30 keV for SEM and from 40 to 400 keV for TEM. Deterioration of the image resolution due to backscattering was quantified for different energies and both detector versions.

A randomized phase II trial comparing every 3-weeks carboplatin/paclitaxel with every 3-weeks carboplatin and weekly paclitaxel in advanced non-small cell lung cancer

BACKGROUND

The optimal schedule of taxane administration has been an area of active interest in several recent clinical trials.

METHODS

To address a pure schedule question, we randomized 161 patients with advanced stage IIIB or IV non-small-cell lung cancer (NSCLC) to either paclitaxel 225 mg/m2 every 3 weeks x 4 cycles or 75 mg/m2/week x 12 (cumulative dose on each arm = 900 mg/m2). Both arms received concurrent carboplatin AUC 6 every 3 weeks x 4 cycles.

RESULTS

The two arms were well-balanced in terms of known prognostic factors. The overall response rate and survival outcomes were similar on the two arms. There was significantly more grade 3/4 thrombocytopenia and grade 2-4 anemia on the weekly arm but less severe myalgias/arthralgias and alopecia. No difference in the rates of peripheral neuropathy was observed; however, patients on the every 3 weeks arm reported significantly more taxane therapy-related side-effects on the functional assessment of cancer therapy taxane subscale.

CONCLUSIONS

This randomized trial exploring schedule-related issues with carboplatin/paclitaxel confirms the versatility of this regimen.

The clinicopathologic basis of Graves' ophthalmopathy: a review

PURPOSE

Graves' ophthalmopathy (GO) is a controversial disease, with disagreement within the medical community regarding its pathogenesis, diagnosis, and treatment.

METHODS

We reviewed recent literature on clinical and pathological aspects of GO from both the endocrinologist's and ophthalmologist's perspective.

RESULTS

Investigations into the pathogenesis of GO have included possible antigenic targets, orbital cell types, and development of animal models. Diagnosis has been improved recently with new tools and grading systems, but can be complicated by conditions that may simulate one or more of the findings of GO. The new findings of clinical studies also compel practitioners to reassess commonly used GO treatments such as orbital irradiation.

CONCLUSIONS

Improved understanding of the pathogenic mechanisms of GO should hopefully lead to new diagnostic and therapeutic approaches to this problematic condition.

Modelling induction of a rotor in cardiac muscle by perpendicular electric shocks

A strong, properly timed shock applied perpendicularly to a propagating wavefront causes a rotor in the canine myocardium. Experimental data indicate that the induction of this rotor relies on the shock exciting tissue away from the electrodes. The computational study reproduced such direct excitation in a two-dimensional model of a 2.7 x 3 cm sheet of cardiac muscle. The model used experimentally measured extracellular potentials to represent 100 and 150 V shocks delivered through extracellular electrodes. The shock-induced transmembrane potential was computed according to two mechanisms, the activating function and the unit-bundle sawtooth potential. The overall process leading to initiation of a rotor was the same in model and experiment. For the 100 V shock, the directly excited region extended 2.26 cm away from the electrode; the centre of the rotor ('critical point') was 1.28 cm away, where the electric field Ecr was 4.54 Vcm(-1). Increasing the shock strength to 150 V moved the critical point 1.02 cm further and decreased Ecr by 0.39 Vcm(-1). The results are comparable with experimental data. The model suggests that the unit-bundle sawtooth is responsible for the creation of the directly excited region, and the activating function is behind the dependence of Ecr on shock strength.