Power Doppler ultrasonography for the assessment of vascular invasion by pancreatic cancer

Clinical impact of intraoperative navigation using a Doppler ultrasonographic guided vessel tracking technique for pancreaticoduodenectomy

During pancreaticoduodenectomy (PD), early ligation of critical vessels such as the inferior pancreaticoduodenal artery (IPDA) has been reported to reduce blood loss. Color Doppler flow imaging has become the useful diagnostic methods for the delineation of the anatomy. In this study, we assessed the utility of the intraoperative Doppler ultrasonography (Dop-US) guided vessel detection and tracking technique (Dop-Navi) for identifying critical arteries in order to reduce operative bleeding. Ninety patients who received PD for periampullary or pancreatic disease were enrolled. After 14 patients were excluded because of combined resection of portal vein or other organs, the remaining were assigned to 1 of 2 groups: patients for whom Dop-Navi was used (n = 37) and those for whom Dop-Navi was not used (n = 39; controls). We compared the ability of Dop-Navi to identify critical vessels to that of preoperative multi-detector computed tomography (MD-CT), using MD-CT data, as well as compared the perioperative status and postoperative outcome between the 2 patient groups. Intraoperative Dop-US was significantly superior to MD-CT in terms of identifying number of vessels and the ability to discriminate the IPDA from the superior mesenteric artery (SMA) based on blood flow velocity. The Dop-Navi patients had shorter operation times (531 min versus 577 min; no significance) and smaller bleeding volumes (1120 mL versus 1590 mL; P < 0.01) than the control patients without increasing postoperative complications. Intraoperative Dop-Navi method allows surgeons to clearly identify the IPDA during PD and to avoid injuries to major arteries.

Enhancement of osteogenic differentiation and proliferation in human mesenchymal stem cells by a modified low intensity ultrasound stimulation under simulated microgravity

Adult stem cells can differentiate into multiple lineages depending on their exposure to differing biochemical and biomechanical inductive factors. Lack of mechanical signals due to disuse can inhibit osteogenesis and induce adipogenesis of mesenchymal stem cells (MSCs). Long-term bed rest due to both brain/spinal cord injury and space travel can lead to disuse osteoporosis that is in part caused by a reduced number of osteoblasts. Thus, it is essential to provide proper mechanical stimulation for cellular viability and osteogenesis, particularly under disuse conditions. The objective of this study was to examine the effects of low intensity pulsed ultrasound (LIPUS) on the osteogenic differentiation of adipose-derived human stem cells (Ad-hMSC) in simulated microgravity conditions. Cells were cultured in a 1D clinostat to simulate microgravity (SMG) and treated with LIPUS at 30mW/cm² for 20 min/day. It was hypothesized that the application of LIPUS to SMG cultures would restore osteogenesis in Ad-hMSCs. The results showed significant increases in ALP, OSX, RANKL, RUNX2, and decreases in OPG in LIPUS treated SMG cultures of Ad-MSC compared to non-treated cultures. LIPUS also restored OSX, RUNX2 and RANKL expression in osteoblast cells. SMG significantly reduced ALP positive cells by 70% (p<0.01) and ALP activity by 22% (p<0.01), while LIPUS treatment restored ALP positive cell number and activity to equivalence with normal gravity controls. Extracellular matrix collagen and mineralization was assessed by Sirius red and Alizarin red staining, respectively. SMG cultures showed little or no collagen or mineralization, but LIPUS treatment restored collagen content to 50% (p<0.001) and mineralization by 45% (p<0.001) in LIPUS treated-SMG cultures relative to SMG-only cultures. The data suggest that LIPUS treatment can restore normal osteogenic differentiation of MSCs from disuse by daily short duration stimulation.

Standards of the Polish Ultrasound Society - update. Pancreas examination

Ultrasound examination of the pancreas constitutes an integral part of the abdominal ultrasound. It is mostly indicated to diagnose pain in the epigastrium, discomfort and jaundice as well as to monitor the patients with acute pancreatitis. The assessment of this organ in an ultrasound examination may be problematic due to its anatomical location and the fact that it might be covered by gastric and duodenal contents as well as due to a number of possible pathological changes, including inflammation and benign or malignant neoplasms, which require differentiation. The basis for establishing a correct diagnosis is the knowledge of the examination technique, correct pancreas structure and images of individual pathologies. This paper presents the standards of ultrasound examination published in 2011 and updated with the current knowledge. The following are discussed: preparation of the patient for the examination, abnormal lesions in the pancreas, acute pancreatitis, chronic pancreatitis, cystic lesions (benign and malignant cysts) and solid focal lesions. Ultrasound is also used to guide the drainage of fluid cisterns, abscesses and cysts. The prime role in the diagnosis and treatment of selected diseases of the upper gastrointestinal tract and parenchymal organs of the abdomen belongs to endosonography of the upper gastrointestinal tract, with the possibility to conduct a fine needle aspiration biopsy, and intraoperative or laparoscopic ultrasound.

Reversal of the detrimental effects of simulated microgravity on human osteoblasts by modified low intensity pulsed ultrasound

Microgravity (MG) is known to induce bone loss in astronauts during long-duration space mission because of a lack of sufficient mechanical stimulation under MG. It has been demonstrated that mechanical signals are essential for maintaining cell viability and motility, and they possibly serve as a countermeasure to the catabolic effects of MG. The objective of this study was to examine the effects of high-frequency acoustic wave signals on osteoblasts in a simulated microgravity (SMG) environment (created using 1-D clinostat bioreactor) using a modified low-intensity pulsed ultrasound (mLIPUS). Specifically, we evaluated the hypothesis that osteoblasts (human fetal osteoblastic cell line) exposure to mLIPUS for 20 min/d at 30 mW/cm(2) will significantly reduce the detrimental effects of SMG. Effects of SMG with mLIPUS were analyzed using the MTS proliferation assay for proliferation, phalloidin for F-actin staining, Sirius red stain for collagen, and Alizarin red for mineralization. Our data showed that osteoblast exposure to SMG results in significant decreases in proliferation (∼ -38% and ∼ -44% on days 4 and 6, respectively; p < 0.01), collagen content (∼ -22%; p < 0.05) and mineralization (∼ -37%; p < 0.05) and actin stress fibers. In contrast, mLIPUS stimulation in SMG condition significantly increases the rate of proliferation (∼24% by day 6; p < 0.05), collagen content (∼52%; p < 0.05) and matrix mineralization (∼25%; p < 0.001) along with restoring formation of actin stress fibers in the SMG-exposed osteoblasts. These data suggest that the acoustic wave can potentially be used as a countermeasure for disuse osteopenia.

Abdominal ultrasonography in detecting and surgical treatment of pancreatic carcinoma

THE AIM OF THE STUDY

was to asses the clinical value of percutaneous abdominal ultrasonography in diagnosis, staging and surgical treatment of patients with pancreatic carcinoma.

MATERIAL AND METHODS

Prospective clinical trial on diagnostic accuracy of percutaneous abdominal ultrasonography was conducted in 409 consecutive patients with pancreatic cancer which were operated on at the I Dept. of General Surgery in Cracow between 2000 and 2010.

RESULTS

Diagnostic accuracy of percutaneous abdominal ultrasonography in pancreatic cancer was 91,1%. The accuracy in detecting different stages of local advancement according to TNM classification was assessed respectively 92.3%-T1, 91.3%-T2, 89.4%-T3, 92.1%-T4, a whole T1-T4 on 91.3%. Diagnostic accuracy of percutaneous abdominal ultrasonography in diagnosis of metastasis to lymph nodes, vascular infiltration, and resectability was respectively 80.7%, 86%, 91.4%.

CONCLUSIONS

Percutaneous abdominal ultrasonography has high diagnostic accuracy in diagnosis, staging and predicting surgical treatment of patients with pancreatic carcinoma.

Significance of color doppler ultrasonography in the assessment of pancreatic carcinoma vascular invasion

Background/Aim. It is highly appreciated to provide exact data on vascular invasion of pancreatic carcinoma relying as much as possible on non-invasive diagnostic procedures. Color Doppler ultrasonography has been proven as an efficient method for clinical staging of pancreatic carcinoma essential for therapeutic decisions. The aim of this study was to provide an analysis of the sensitivity and specificity for color Doppler ultrasonography in patients suffering from pancreatic carcinoma. Methods. We performed color Doppler ultrasonography examination in 43 patients with pancreatic carcinoma prior to the surgery. The findings of ultrasonography on neoplasm vascular invasion were correlated to the findings obtained during the subsequent surgical procedures. An estimation of neoplastic invasion of certain blood vessels including portal vein, celiac trunk, and superior mesenteric artery and vein is critical for decision making regarding surgical treatment. The patients with metastases of pancreatic carcinoma were excluded from the study. Results. Comparing color Doppler and the surgical findings we estimated the sensitivity for detection of neoplastic vascular invasion ranging from 79?93%, whereas the specificity range was from 83?93%. Conclusion. Color Doppler ultrasonography is a sufficiently sensitive and specific method for evaluation of vascular invasion in pancreatic carcinoma patients. Since color Doppler ultrasonography is a non-invasive, radiation free, and inexpensive diagnostic tool, considering also the results of this and similar studies we could strongly recommend its use for an initial presurgical evaluation of vascular invasion in pancreatic carcinoma patients.

Assessment of portal vein invasion in pancreatic cancer by fusion 3-dimensional ultrasonography

OBJECTIVE

The purpose of this study was to assess the usefulness of a newly developed imaging technique, fusion 3-dimensional ultrasonography (3DUS) in the diagnosis of portal vein (PV) invasion in patients with pancreatic cancer (PC).

METHODS

Fourteen patients with proven PC were examined by fusion 3DUS presented as shaded volume-rendering and multiplanar reconstruction images. The surgical findings were obtained in all patients (12 with resection and 2 without). The findings were compared with those of 2-dimensional ultrasonography (2DUS), contrast-enhanced computed tomography (CT), dynamic CT (DCT), angiography, and surgical findings. Portal vein invasion was assessed by 3 independent radiologists for each modality, and objectivity of the assessment was examined by interobserver variability analysis (kappa value).

RESULTS

On the basis of surgical findings, the accuracy rates of 2DUS, fusion 3DUS, DCT, and angiography were 78.6%, 92.9%, 85.3%, and 66.7%, respectively. The kappa values of 2DUS, fusion 3DUS, DCT, and angiography for PV invasion were 0.57, 0.90, 0.63, and 0.49, respectively, being most objective in fusion 3DUS.

CONCLUSIONS

Fusion 3DUS is useful for diagnosis of PV invasion of PC.

Malignant biliary obstruction: value of imaging findings

This review focuses on the clinical impact of different modalities to image primary and secondary malignant biliary obstruction. The detection and staging of cancers of the pancreatic and biliary tract are best accomplished with endoscopic ultrasound, contrast-enhanced computed tomography, and magnetic resonance cholangiopancreatography. Three-dimensional ultrasound is a new noninvasive method that may be used increasingly as an initial test to select patients who require further diagnostic evaluation by magnetic resonance cholangiopancreatography or therapeutic endoscopic retrograde cholangiopancreatography. All-in-one computed tomography including three-dimensional reconstructions of the biliary tree may be competitive against all-in-one magnetic resonance imaging for diagnosis and staging of pancreatic tumors. Magnetic resonance cholangiopancreatography is excellent for identifying the presence and the level of biliary obstruction. With newer diagnostic imaging technologies emerging, endoscopic retrograde cholangiopancreatography is evolving into a predominantly therapeutic procedure.

Analysis of long-term survivors after surgical resection for invasive pancreatic cancer

Pancreatic cancer remains a lethal disease. Although there are many reports on the survival rates of pancreatic cancer patients after surgical resection, the clinicopathological characteristics that influence long-term survival over 5 years remain controversial. Here, we clarify the favourable prognostic factors for long-term survival. One hundred and eighty-two patients with pancreatic cancer underwent surgical resections from 1981 to 1997 in our department. Among them, eight patients survived for at least 5 years after the surgery. The clinicopathological characteristics of the eight long-term survivors who underwent radical resections were studied retrospectively. R0 surgical resections, including five combined with portal vein resections (62.5%), were achieved in these eight patients. Negative invasions of the major regional artery (seven of eight, 87.5%) and to the extrapancreatic nerve plexus (seven of eight, 87.5%), and N0 or Nl lymph node metastasis (7 of 8, 87.5%) were detected as clinicopathological features of long-term survivors in our study. No exposure of carcinoma at the dissected surface and cut end (seven of eight, 87.5%) was characteristically confirmed by pathology. Portal vein invasion was seen in three of the eight patients (37.5%). For long-term survival in cases of pancreatic cancer, complete R0 resections should be performed and negative invasions in the major regional arteries and to the extrapancreatic plexus of the nerve were necessary. No invasion to the portal vein was not necessarily required if R0 was achieved by combined resection of the portal vein.

Clinical significance of intraportal endovascular ultrasonography for the diagnosis of extrapancreatic nerve plexus invasion by pancreatic carcinoma

BACKGROUND/AIMS

The extrapancreatic nerve plexus (PL) invasion is a common feature of pancreatic cancer and affects the outcome of the patients after surgical resection. IPEUS with high-resolution probes can visualize the PL invasion with high overall accuracy rate. The aim of this study is to evaluate the clinical significance of the PL invasion diagnosed intraoperatively by intraportal endovascular ultrasonography (IPEUS).

METHODS

IPEUS was performed in 64 patients who underwent the pancreatic resection. Several clinicopathological factors were studied in patients with or without PL invasion.

RESULTS

There were 18 cases in which PL invasion was confirmed pathologically. IPEUS showed 94% sensitivity, 98% specificity and 97% accuracy for the diagnosis of the PL invasion with the false-positive rate of 5.6%. The 1-, 2- and 3-year survival in 18 patients with PL invasion was 30, 6 and 0% in comparison to 52, 32 and 18% in those 46 patients without PL invasion and the difference was statistically significant (p = 0.008). A significant correlation was found between PL invasion and the portal vein invasion, invasion of the margins or pTNM stage.

CONCLUSIONS

According to current results, the prognosis of the cases with PL invasion is very poor and indication for resection is doubtful. We conclude that the cases in which PL invasion is diagnosed by IPEUS are not indicated for extended resection and correct diagnosis of PL invasion is important not only to predict the outcome but also to decide the surgical procedure for obtaining negative margins while improving the quality of life after surgery.