Intraoperative Ultrasound of the Pancreas

Value of Intraoperative Sonography in Pancreatic Surgery

The utility of intraoperative sonography for pancreatic disease has been well described for detection and evaluation of neoplastic and inflammatory pancreatic disease. Intraoperative sonography can help substantially reduce surgical time as well as decrease potential injury to tissues and major structures. Imaging with sonography literally at the point of care--the surgeon's scalpel--can precisely define the location of pancreatic lesions and their direct relationship with surrounding structures in real time during surgery. This article highlights our experience with intraoperative sonography at multiple institutional sites for both open and laparoscopic surgical procedures. We use intraoperative sonography for a wide range of pancreatic disease to provide accurate localization and staging of disease, provide guidance for enucleation of nonpalpable, nonvisible tumors, and in planning the most direct and least invasive surgical approach, avoiding injury to the pancreatic duct or other vital structures.

Chronic pancreatitis: A surgical disease? Role of the Frey procedure

Although medical treatment and endoscopic interventions are primarily offered to patients with chronic pancreatitis, approximately 40% to 75% will ultimately require surgery during the course of their disease. Although pancreaticoduodenectomy has been considered the standard surgical procedure because of its favorable results on pain control, its high postoperative complication and pancreatic exocrine or/and endocrine dysfunction rates have led to a growing enthusiasm for duodenal preserving pancreatic head resection. The aim of this review is to better understand the rationale underlying of the Frey procedure in chronic pancreatitis and to analyze its outcome. Because of its hybrid nature, combining both resection and drainage, the Frey procedure has been conceptualized based on the pathophysiology of chronic pancreatitis. The short and long-term outcome, especially pain relief and quality of life, are better after the Frey procedure than after any other surgical procedure performed for chronic pancreatitis.

Intraoperative ultrasonography of the pancreas

Intraoperative ultrasonography (US) of the pancreas is a versatile technique that provides excellent spatial and contrast resolution and real-time imaging capabilities, making it useful for diagnostic imaging as well as for guidance of laparoscopic and open operative procedures. Intraoperative US may be used for applications such as staging and localizing tumors; performing regional metastatic surveys; documenting arterial and venous patency; identifying endocrine tumors; distinguishing pancreatitis from a neoplasm; and guiding biopsy, duct cannulation, and drainage of abscesses or cysts. The scanning approach and technique vary according to the application, with many different equipment and transducer options and sterilization methods available. With increasing clinical demands for intraoperative US, it is essential that radiologists be familiar with its uses and technique. In addition, to properly perform intraoperative US and accurately interpret the images, knowledge of normal and variant pancreatic and vascular anatomy and relevant landmarks is needed. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.307105051/-/DC1.

Intraoperative ultrasound of the pancreas

Intraoperative ultrasound provides spatial resolution of the pancreas superior to computed tomography, magnetic resonance imaging, and transabdominal sonography. This pictorial essay will review common benign and malignant pancreatic processes including the following: pancreatic ductal adenocarcinoma, pancreatitis, endocrine tumors, mucinous cystic neoplasm, intraductal papillary mucinous neoplasm, serous cystadenoma, and solid pseudopapillary tumor. The use of intraoperative ultrasound in specific surgical situations will be discussed, which include the following: (1) identification of insulinoma(s) which are not detectable preoperatively, (2) identification of the pancreatic duct to determine dissection planes for chronic pancreatitis surgery (eg, Puestow procedure) and for tumor resection, and (3) staging purposes for malignant disease.

Navigated ultrasound in laparoscopic surgery

Laparoscopic surgery is performed through small incisions that limit free sight and possibility to palpate organs. Although endoscopes provide an overview of organs inside the body, information beyond the surface of the organs is missing. Ultrasound can provide real-time essential information of inside organs, which is valuable for increased safety and accuracy in guidance of procedures. We have tested the use of 2D and 3D ultrasound combined with 3D CT data in a prototype navigation system. In our laboratory, micro-positioning sensors were integrated into a flexible intraoperative ultrasound probe, making it possible to measure the position and orientation of the real-time 2D ultrasound image as well as to perform freehand 3D ultrasound acquisitions. Furthermore, we also present a setup with the probe optically tracked from the shaft with the flexible part locked in one position. We evaluated the accuracy of the 3D laparoscopic ultrasound solution and obtained average values ranging from 1.6% to 3.6% volume deviation from the phantom specifications. Furthermore, we investigated the use of an electromagnetic tracking in the operating room. The results showed that the operating room setup disturbs the electromagnetic tracking signal by increasing the root mean square (RMS) distance error from 0.3 mm to 2.3 mm in the center of the measurement volume, but the surgical instruments and the ultrasound probe added no further inaccuracies. Tracked surgical tools, such as endoscopes, pointers, and probes, allowed surgeons to interactively control the display of both registered preoperative medical images, as well as intraoperatively acquired 3D ultrasound data, and have potential to increase the safety of guidance of surgical procedures.

Factors affecting outcome after Frey procedure for chronic pancreatitis

BACKGROUND

Debilitating abdominal pain remains the most common presentation of chronic pancreatitis and the treatment remains challenging.

OBJECTIVE

This prospective study analyzed the outcome of Frey's procedure in patients with inflammatory head mass.

METHODS

For the period between 2002 and 2007, 77 patients with chronic pancreatitis underwent Frey procedure for intractable abdominal pain. The mean follow-up was 14 months. For the purpose of analysis of the outcome, patients were grouped as poor pain control (19%) and good pain control groups (81%) based on the pain scores during follow-up.

RESULTS

There was no 30-day mortality. The logistic regression analysis showed that decreased volume percentage (48%) of head mass resected (p=0.003) and small diameter of the pancreatic duct (p=0.05) were associated with poor pain outcome. Subgroup analysis revealed that patients with small duct disease were associated with increased operative time (p=0.001), poor pain scores (p=0.001), and increased weight loss (p=0.003) during follow-up.

CONCLUSIONS

Frey procedure can be performed with zero mortality and low morbidity in a high-volume center. It provides good pain relief in majority of the patients. Volume of the head mass cored affects pain outcome. Correlation between poor results in terms of pain relief and weight loss following Frey's procedure, and small duct disease supports the view that duct diameter is an important predictor of pain relief.