Determination of the transection margin during colorectal resection with hyperspectral imaging (HSI).

PURPOSE: This study evaluated the use of hyperspectral imaging for the determination of the resection margin during colorectal resections instead of clinical macroscopic assessment. METHODS: The used hyperspectral camera is able to record light spectra from 500 to 1000 nm and provides information about physiologic parameters of the recorded tissue area intraoperatively (e.g., tissue oxygenation and perfusion). We performed an open-label, single-arm, and non-randomized intervention clinical trial to compare clinical assessment and hyperspectral measurement to define the resection margin in 24 patients before and after separation of the marginal artery over 15 min; HSI was performed each minute to assess the parameters mentioned above. RESULTS: The false color images calculated from the hyperspectral data visualized the margin of perfusion in 20 out of 24 patients precisely. In the other four patients, the perfusion difference could be displayed with additional evaluation software. In all cases, there was a deviation between the transection line planed by the surgeon and the border line visualized by HSI (median 1 mm; range - 13 to 13 mm). Tissue perfusion dropped up to 12% within the first 10 mm distal to the border line. Therefore, the resection area was corrected proximally in five cases due to HSI record. The biggest drop in perfusion took place in less than 2 min after devascularization. CONCLUSION: Determination of the resection margin by HSI provides the surgeon with an objective decision aid for assessment of the best possible perfusion and ideal anastomotic area in colorectal surgery.

[Possibilities and perspectives of hyperspectral imaging in visceral surgery]. / Möglichkeiten und Perspektiven der Hyperspektralbildgebung in der Viszeralchirurgie.

HyperSpectral Imaging (HSI) technology enables quantitative tissue analyses beyond the limitations of the human eye. Thus, it serves as a new diagnostic tool for optical properties of diverse tissues. In contrast to other intraoperative imaging methods, HSI is contactless, noninvasive, and the administration of a contrast medium is not necessary. The duration of measurements takes only a few seconds and the surgical procedure is only marginally disturbed. Preliminary HSI applications in visceral surgery are promising with the potential of optimized outcomes. Current concepts, possibilities and new perspectives regarding HSI technology together with its limitations are discussed in this article.

[Hyperspectral imaging of gastrointestinal anastomoses]. / Hyperspektral-Imaging bei gastrointestinalen Anastomosen.

INTRODUCTION: Anastomotic insufficiency (AI) remains the most feared surgical complication in gastrointestinal surgery, which is closely associated with a prolonged inpatient hospital stay and significant postoperative mortality. Hyperspectral imaging (HSI) is a relatively new medical imaging procedure which has proven to be promising in tissue identification as well as in the analysis of tissue oxygenation and water content. Until now, no data exist on the in vivo HSI analysis of gastrointestinal anastomoses. METHODS: Intraoperative images were obtained using the TIVITA™ tissue system HSI camera from Diaspective Vision GmbH (Pepelow, Germany). In 47 patients who underwent gastrointestinal surgery with esophageal, gastric, pancreatic, small bowel or colorectal anastomoses, 97 assessable recordings were generated. Parameters obtained at the sites of the anastomoses included tissue oxygenation (StO2), the tissue hemoglobin index (THI), near-infrared (NIR) perfusion index, and tissue water index (TWI). RESULTS: Obtaining and analyzing the intraoperative images with this non-invasive imaging system proved practicable and delivered good results on a consistent basis. A NIR gradient along and across the anastomosis was observed and, furthermore, analysis of the tissue water and oxygenation content showed specific changes at the site of anastomosis. CONCLUSION: The HSI method provides a non-contact, non-invasive, intraoperative imaging procedure without the use of a contrast medium, which enables a real-time analysis of physiological anastomotic parameters, which may contribute to determine the "ideal" anastomotic region. In light of this, the establishment of this methodology in the field of visceral surgery, enabling the generation of normal or cut off values for different gastrointestinal anastomotic types, is an obvious necessity.

Genomic structure and chromosomal localization of the novel ETS factor, PE-2 (ERF).

The members of the ETS family of transcription factors are grouped because they share a highly conserved DNA binding domain. These factors are involved in growth factor pathways and regulate both proliferation and differentiation. To identify ETS factors that may be involved in early hematopoietic progenitor regulation, we isolated a novel member of the ETS family by reverse transcriptase-PCR of the conserved DNA binding domain using degenerate oligonucleotides. This gene directs the synthesis of a 2704-nucleotide transcript whose largest open reading frame encodes a 548-amino-acid protein. Northern blot analysis reveals ubiquitous expression in all human tissues and cell lines tested, with highest levels in the testis, ovary, pancreas, and heart. Comparison of this gene with the available databases reveals very significant homology to the ETS factor PE-1 and probable near-identity with the recently cloned factor ERF. The PE-2 gene is composed of four exons spanning over 9 kb of genomic DNA. Sequence analysis of the promoter region reveals a GC-rich sequence without a TATA motif and with putative binding motifs for CREB, c-myb, and AP-1 factors. Using mouse-human somatic hybrids and FISH analysis, the PE-2 gene is localized to human chromosome 19q13.2, a region involved in translocations and deletions in leukemias and several solid tumors, suggesting that this novel ETS factor may play a role in carcinogenesis.