Pancreatic rest resection using band ligation snare polypectomy.

BACKGROUND: Although pancreatic rests have characteristic endoscopic features, confirming a histological diagnosis may be desirable to exclude other significant pathology. AIMS: The aim of this study was to assess the efficacy and safety of endoscopic band ligation snare polypectomy (EBLSP) for removal of suspected pancreatic rests and to compare the diagnostic yield to other endoscopic tissue sampling methods. METHODS: An electronic endoscopic report database was searched for patients referred for evaluation of incidentally found gastric antral subepithelial lesions. Tissue sampling technique, pathology, and complications were recorded. RESULTS: Removal of suspected pancreatic rests with EBLSP was successful in all 21 cases without complications. Nineteen of 21 (90%) who underwent EBLSP had a histological diagnosis of heterotopic pancreas compared with 5 of 14 (36%) who underwent tissue sampling with biopsy and/or snare (P = 0.001). The endoscopic characteristics of the histology proven pancreatic rests were an antral subepithelial mass with central umbilication measuring 6-10 mm in diameter and located 2-6 cm from the pylorus in the 3-7 o'clock position. CONCLUSIONS: Endoscopic band ligation snare polypectomy resection of gastric antral lesions suspected to be pancreatic rests had a diagnostic yield superior to standard biopsy forceps and snare polypectomy techniques. However, because all pathologically confirmed pancreatic rests had typical endoscopic appearances of pancreatic rests, it may not be necessary to obtain histologic diagnosis for every suspected gastric antral heterotopic pancreas.

Endoscopic ultrasound staging and novel therapeutics for pancreatic cancer.

Pancreatic cancer remains a challenging disease, being the fourth leading cause of death in both men and women in the United States. Patients with pancreatic cancer present with symptoms including jaundice, pruritus, and weight loss, which often herald advanced disease with little chance for curative resection. Multiple imaging modalities are used to diagnose and stage pancreatic cancer. This article discusses the utility of endoscopic ultrasound (EUS) for diagnosis and staging, and introduces novel EUS-guided therapeutic options for the treatment of pancreatic cancers. EUS-guided fine-needle injection of chemotherapy agents is a promising development in pancreatic tumor treatment.

Infrared differential-absorption Mueller matrix spectroscopy and neural network-based data fusion for biological aerosol standoff detection.

An active spectrophotopolarimeter sensor and support system were developed for a military/civilian defense feasibility study concerning the identification and standoff detection of biological aerosols. Plumes of warfare agent surrogates gamma-irradiated Bacillus subtilis and chicken egg white albumen (analytes), Arizona road dust (terrestrial interferent), water mist (atmospheric interferent), and talcum powders (experiment controls) were dispersed inside windowless chambers and interrogated by multiple CO(2) laser beams spanning 9.1-12.0 microm wavelengths (lambda). Molecular vibration and vibration-rotation activities by the subject analyte are fundamentally strong within this "fingerprint" middle infrared spectral region. Distinct polarization-modulations of incident irradiance and backscatter radiance of tuned beams generate the Mueller matrix (M) of subject aerosol. Strings of all 15 normalized elements {M(ij)(lambda)/M(11)(lambda)}, which completely describe physical and geometric attributes of the aerosol particles, are input fields for training hybrid Kohonen self-organizing map feed-forward artificial neural networks (ANNs). The properly trained and validated ANN model performs pattern recognition and type-classification tasks via internal mappings. A typical ANN that mathematically clusters analyte, interferent, and control aerosols with nil overlap of species is illustrated, including sensitivity analysis of performance.

Infrared Mueller matrix acquisition and preprocessing system.

An analog Mueller matrix acquisition and preprocessing system (AMMS) was developed for a photopolarimetric-based sensor with 9.1-12.0 microm optical bandwidth, which is the middle infrared wavelength-tunable region of sensor transmitter and "fingerprint" spectral band for chemical-biological (analyte) standoff detection. AMMS facilitates delivery of two alternate polarization-modulated CO(2) laser beams onto subject analyte that excite/relax molecular vibrational resonance in its analytic mass, primes the photoelastic-modulation engine of the sensor, establishes optimum throughput radiance per backscattering cross section, acquires Mueller elements modulo two laser beams in hexadecimal format, preprocesses (normalize, subtract, filter) these data, and formats the results into digitized identification metrics. Feed forwarding of formatted Mueller matrix metrics through an optimally trained and validated neural network provides pattern recognition and type classification of interrogated analyte.