Investigation of the applicability of virtual gastroscopy based on postmortem computed tomography to detect changes in the stomach, along with reports of three rare cases

Postmortem computed tomography is now being used more commonly for routine forensic investigation. The use of 3D reconstruction techniques including virtual gastroscopy is effective and also improves the speed of interpretation, recognition, and description of specific clinical conditions. However, it has been unclear whether postmortem virtual endoscopy could be applicable for medicolegal autopsy or whether it could complement pathological examination at autopsy. Here, we investigated the applicability of postmortem virtual gastroscopy by reviewing 295 medicolegal autopsy cases seen at our institution, and found four cases in which the technique had been able to demonstrate features corresponding to changes that were evident at autopsy. Thus,postmortem virtual gastroscopy would have only rarely been effective forvisualizing any change in the stomach in such cases. In addition, we describe in detail three of those cases in which virtual gastroscopy had been able to visualize changes in the stomach, including a gastric ulcer, a polyp, and the presence of foamy fluid, which were all verified at autopsy. In those cases, virtual gastroscopy was useful for understanding features in the stomach of the deceased, which were revealed by axial images of the abdomen, to forensic pathologists who were not familiar with PMCT 2D images. Taken together, our findings suggest that postmortem virtual gastroscopy might help facilitate clear, straightforward sharing of information about PMCT images of complex anatomical structures among radiologists and forensic pathologists, as well as non-medical professionals with a limited knowledge of anatomy and physiology.

Preoperative Staging of Gastric Cancer Using Computed Tomography and Its Correlation with Histopathology with Emphasis on Multi-planar Reformations and Virtual Gastroscopy

BACKGROUND

Gastric cancer is the fifth most common cancer in the world. Preoperative staging of gastric cancer has assumed pivotal role in deciding appropriate management of gastric cancer with multi-detector computed tomography (MDCT) using hydro- and gaseous distension of stomach superseding endoscopic ultrasound in tumor (T) and nodal (N) staging. We undertook this study to evaluate the diagnostic accuracy of MDCT in the T and N staging of gastric cancer with an attempt to differentiate between early and advanced gastric carcinomas.

METHODS

A total of 160 patients with endoscopically diagnosed and biopsy-proven gastric cancer were subjected to MDCT after adequate gaseous and hydro-distention of stomach. Multi-planar reformatted (MPR) as well as virtual gastroscopy images were also obtained. Gastric lesions were categorized into T1 to T4 stages with N staging from N0 to N3. Preoperative CT findings were correlated with histopathological findings.

RESULTS

Overall diagnostic accuracy of T staging in our study was 82.5% (132/160) with an accuracy of 75% (120/160) for N staging. The diagnostic accuracy of CT for early gastric carcinoma in our study was 93.75% with high specificity of 96% but low sensitivity of 66.7%.

CONCLUSION

MDCT using gaseous and hydro-distension of stomach is an excellent modality for near accurate preoperative T staging of gastric cancer. However, CT has a limited role in the N staging of gastric cancer. This study also suggested that the combined use of virtual gastroscopy and MPR images helps in better detection of early gastric cancers.