Nihon Geka Gakkai zasshi最新文献

Pulmonary segmentectomy-level variations in the three-dimensional (3D) architecture of the bronchi and pulmonary vessels are much wider than those at the lobectomy level. Presurgical simulation with sharing of necessary information is believed to reduce the surgical time and number of detachment procedures required. For such simulations, the author’s group developed homemade software that: 1) reconstructs the shapes of the bronchi, vessels, lung, and tumors as simplified 3D images such as sequentially connected cylinders with branches and membranes from digital-imaging data on a personal computer screen; 2) allows surgeons to input data on the initial and terminal points, diameters of cylinders, etc. continuously by moving computed tomography (CT) images up and down; and 3) permits these data to be read by modeler shareware on the Internet. Although conventional 3D images from CT data are reconstructed by a volume-rendering method, those of the software developed by the author’s group are made using a surface-rendering method. This article explains the present status of and future trends in the actual processes of simulated surgery including segmentectomy and navigation, applications of newly developed operative procedures, and results of data analysis of more than 500 cases.

Preoperative simulation and intraoperative navigation using three-dimensional (3D) analysis has been established and is indispensable in liver surgery. However, 3D analysis has not been developed in pancreatic surgery. Recently, we have been able to perform 3D analysis of the pancreas and make 3D models of it with surrounding vascular structures and tumors using a 3D printer. Preoperative computed tomography (CT) images were reconstructed in a 3D configuration, including the pancreatic parenchyma, tumors, pancreatic duct, bile duct, portal venous system, and hepatic and superior mesenteric arteries. Pancreas models with internal structures in color were made of soft resin with a 3D printer. The 3D printed models were made in cases when patients were to undergo laparoscopic distal pancreatectomy and pancreatoduodenectomy with anomalies of the hepatic arteries, i.e., the replaced right hepatic artery. Preoperatively, the surgeons simulated surgical plans using the 3D model and acquired real images of surgical procedures. Intraoperatively, the surgeons performed pancreatic resection with navigation using the 3D pancreas model in a sterilization bag. Simulation and navigation using 3D analysis and 3D printed pancreas models can be useful in pancreatic surgery, in cases of laparoscopic surgery, and in patients with vascular anomalies.

Recent developments in multidetector-row computed tomography (CT) provide precise information on liver anatomy. In the early 2000s, liver simulation based on three-dimensional (3D)-CT enabled estimation of total liver volume and liver volume flown from the portal vein or drained by the hepatic vein, facilitating liver resection planning. Additionally, 3D-CT simulation is useful for graft selection in living-donor liver transplantation. From April 2012, the simulation technique has been covered by the Japanese national health insurance system. Compared with the dissemination of liver simulation, liver surgery navigation is still in the developing stage. Recently, our group has clinically applied real-time virtual sonography, which synchronizes preoperative CT and supports tumor identification. The drawback of the system is the synchronization accuracy of both images. Another intraoperative navigation technique available is fluorescence imaging using indocyanine green (ICG) as a fluorescence source. ICG-fluorescence imaging enables the identification of liver malignancies, the bile duct, portal segment, and veno-occlusive regions in real time. However, deeply located (>10 mm) structures cannot be visualized because near-infrared light lacks tissue-penetration ability. Further technological advances are expected to improve liver surgery navigation and enhance the safety of liver surgery.

The estrogen receptor (ER), progesterone receptor (PgR), human epidermal growth factor receptor type 2 (HER2), and Ki67 are biomarkers for early breast cancer. These markers are usually examined by immunohistochemistry (IHC), and positive is defined as more than 1％ for ER or PgR, and a score of 3+ or 2+ with in situ hybridization positivity for HER2. Indications for endocrine therapy and anti-HER2 therapy are determined according to these cutoff values. These markers are also clinically useful for classifying IHC-based subtypes. Although a cutoff value for Ki67 has yet to be determined, ER-positive/HER2-negative breast cancer is further divided into luminal A or B using Ki67 and PgR expression levels. In addition, multigene assays are clinically available to assess the indications for chemotherapy. Since a discordance in biomarkers between primary and metastatic cancer occurs in some cases, rebiopsy is recommended. It is also important to take measures to ensure the accuracy of IHC procedures because the results can easily be affected by a number of factors. The appropriate treatment should be selected by taking the clinical significance of these biomarkers into consideration.