Management of Surgically Accessible Lymph Nodes Beyond Normal Resection Planes.

This article discusses the management of isolated metastatic lymph nodes for colon and rectal cancer. There are traditionally significant differences in how certain regions of lymph nodes for colon and rectal cancer are managed in the East and West. This has led to the development of the lateral lymph node dissection for rectal cancer and extended lymphadenectomy techniques for colon cancer. This article will evaluate the literature on these techniques and what the surgical and oncological outcomes are at this time. In addition, colon and rectal cancers can occasionally have isolated distant lymph node metastases. These would traditionally be treated as systemic disease with chemotherapy. There is consideration though that these could be treated as similar to isolated liver or lung metastases which have been shown to be able to be treated surgically with good oncological results. The literature for these isolated distant lymph node metastases will be reviewed and treatment options available will be discussed.

Safety of Transrectal or Transvaginal Drainage of Pelvic Abscesses / Segurança da drenagem transretal ou transvaginal de abscessos pélvicos

Abstract Objective The literature on the safety and long-term sequelae of transrectal and transvaginal drainage of pelvic abscesses is limited. We evaluated the outcomes and safety of pelvic abscess drainage by interventional radiology at our institution. Methods After obtaining institutional review board approval, we retrospectively evaluated the outcomes of transrectal and transvaginal pelvic abscesses drainage using computed tomography, endorectal ultrasound, and or fluoroscopy. Results The study included 26 patients, with an age range of 24 to 88 years old, out of whom 53.8% were men. A total of 46.1% of the participants were African Americans and 26.9% were Caucasians. The average body mass index was 28.4 (range: 15.6 to 41.9). The most common etiology was penetrating abdominal injury (27%), followed by appendectomy (23%), diverticular disease (11.5%), anastomotic leak (11.5%), and disorders of gynecological causes (11.5%). The mean abscess diameter was 6.3 cm (range: 3.3 to 10.0 cm). Transrectal drainage was performed in all except one patient who had a transvaginal drainage. Transrectal ultrasound was used for drainage in 92.3% cases, and fluoroscopy was used as an additional imaging modality in 75% of the cases. An 8- or 10-Fr pigtail catheter was used in>80% of the patients. Drains were removed between 2 and 7 days in 92.3% of the cases. The average follow-up was 30.4 months (range: 1 to 107 months), and no long-term complications were reported. Only one patient required subsequent operative intervention for an anastomotic leak. Conclusions Pelvic abscess drainage by transrectal route using radiological guidance is a safe and effective procedure.

Resumo Objetivo A literatura sobre a segurança e as sequelas no longo prazo da drenagem transretal e transvaginal do abscesso pélvico é limitada. Avaliamos os resultados e a segurança da drenagem do abscesso pélvico por radiologia intervencionista em nossa instituição. Métodos Após obter a aprovação do conselho de revisão institucional, avaliamos retrospectivamente os resultados da drenagem de abscessos pélvicos transretais e transvaginais por meio de tomografia computadorizada, ultrassom endorretal, e/ou fluoroscopia. Resultados Participaram do estudo 26 pacientes, com faixa etária de 24 a 88 anos, dos quais 53,8% eram homens. Um total de 46,1% eram afro-descendentes, e 26,9% eram brancos. O índice de massa corporal médio foi de 28,4 (gama: 15,6 a 41,9). A etiologia mais comum foi lesão abdominal penetrante (27%), seguida de apendicectomia (23%), doença diverticular (11,5%), fístula anastomótica (11,5%) e distúrbios de causas ginecológicas (11,5%). O diâmetro médio do abscesso foi de 6,3 cm(gama: 3,3 a 10,0 cm). A drenagem transretal foi realizada em todos os pacientes, com exceção de uma, que foi submetida a uma drenagem transvaginal. A ultrassonografia transretal foi utilizada para drenagem em 92,3% dos casos, e a fluoroscopia como modalidade adicional de imagem, em 75% dos casos. Um catéter duplo J de 8 ou 10 Fr foi usado em>80% dos pacientes. Os drenos foram retirados entre 2 e 7 dias em 92,3% dos casos. O acompanhamentomédio foi de 30,4meses (gama: 1 a 107 meses), e nenhuma complicação de longo prazo foi relatada. Apenas um paciente necessitou de intervenção cirúrgica subsequente para um vazamento anastomótico. Conclusão A drenagem do abscesso pélvico por via transretal com orientação radiológica é um procedimento seguro e eficaz.

Corrigendum: Space charge limited conduction mechanism in GaAsSb nanowires and the effect of in-situ annealing in ultra-high vacuum (2020 Nanotechnology 31 025205).

In this work, the first observation of the space charge limited conduction mechanism (SCLC) in GaAsSb nanowires (NWs) grown by Ga-assisted molecular beam epitaxial technique, and the effect of ultrahigh vacuum in-situ annealing have been investigated. The low onset voltage of the SCLC in the NW configuration has been advantageously exploited to extract trap density and trap distribution in the bandgap of this material system, using simple temperature dependent current-voltage measurements in both the ensemble and single nanowires. In-situ annealing in an ultra-high vacuum revealed significant reduction in the trap density from 1016 cm-3 in as-grown NWs to a low level of 7 * 1014 cm-3 and confining wider trap distribution to a single trap depth at 0.12 eV. A comparison of current conduction mechanism in the respective single nanowires using conductive atomic force microscopy (C-AFM) further confirms the SCLC mechanism identified in GaAsSb ensemble device to be intrinsic. Higher current observed in current mapping by C-AFM, increased 4K photoluminescence (PL) intensity along with reduced full-width half maxima and more symmetric PL spectra, reduced asymmetrical broadening and increased TO/LO mode in room temperature Raman spectra for in-situ annealed NWs again attest to effective annihilation of traps leading to the improved optical quality of NWs compared to as-grown NWs. Hence, the I-V-T analysis of the SCLC mechanism has been demonstrated to be a simple approach to obtain information on growth induced traps in the NWs.

Space charge limited conduction mechanism in GaAsSb nanowires and the effect of in situ annealing in ultra-high vacuum.

In this work, the first observation of the space charge limited conduction mechanism (SCLC) in GaAsSb nanowires (NWs) grown by Ga-assisted molecular beam epitaxial technique, and the effect of ultra-high vacuum in situ annealing have been investigated. The low onset voltage of the SCLC in the NW configuration has been advantageously exploited to extract trap density and trap distribution in the bandgap of this material system, using simple temperature dependent current-voltage measurements in both the ensemble and single nanowires. In situ annealing in ultra-high vacuum revealed significant reduction in the trap density from 1016 cm-3 in as-grown NWs to a low level of 7 × 1014 cm-3 and confining wider trap distribution to a single trap depth at 0.12 eV. A comparison of current conduction mechanism in the respective single nanowires using conductive atomic force microscopy (C-AFM) further confirms the SCLC mechanism identified in GaAsSb ensemble device to be intrinsic. Higher current observed in current mapping by C-AFM, increased 4 K photoluminescence (PL) intensity along with reduced full-width half maxima and more symmetric PL spectra, and reduced asymmetrical broadening with increased TO/LO mode in room temperature Raman spectra for in situ annealed NWs again attest to effective annihilation of traps leading to the improved optical quality of NWs compared to as-grown NWs. Hence, the I-V-T analysis of the SCLC mechanism has been demonstrated as a simple approach to obtain information on growth induced traps in the NWs.

Epidemiology and Pathophysiology of Diverticular Disease.

Colonic diverticular disease is a common health care issue which has historically been attributed to western countries and older age population. Recent studies have shown a rise in incidence among developing countries that have adopted western diets as well as rise in prevalence among younger patients. In this article, the authors discuss the incidence, epidemiology, and pathophysiology of colonic diverticular disease.

Anorectal melanoma.

Anorectal melanoma is a disease that can be difficult to diagnose because of its unclear presentation. After diagnosis, the main treatment available is surgical resection. Sentinel lymph node mapping has an unclear role in its management. Adjuvant therapy has long been recommended; however, there are no strong data to support its use. Prognostic factors to help gauge survival are also not clear; nevertheless, there is a strong association between stage of disease and histologic perineal invasion. Anorectal melanoma is a very rare disease with a dismal prognosis.