Arterial Spin Labeled Perfusion MRI for the Evaluation of Response to Tyrosine Kinase Inhibition Therapy in Metastatic Renal Cell Carcinoma.

Background Tumor perfusion may inform therapeutic response and resistance in metastatic renal cell carcinoma (RCC) treated with antiangiogenic therapy. Purpose To determine if arterial spin labeled (ASL) MRI perfusion changes are associated with tumor response and disease progression in metastatic RCC treated with vascular endothelial growth factor receptor (VEGFR) tyrosine kinase inhibitors (TKIs). Materials and Methods In this prospective study (ClinicalTrials.gov identifier: NCT00749320), metastatic RCC perfusion was measured with ASL MRI before and during sunitinib or pazopanib therapy between October 2008 and March 2014. Objective response rate (ORR) and progression-free survival (PFS) were calculated. Perfusion was compared between responders and nonresponders at baseline, at week 2, after cycle 2 (12 weeks), after cycle 4 (24 weeks), and at disease progression and compared with the ORR by using the Wilcoxon rank sum test and with PFS by using the log-rank test. Results Seventeen participants received sunitinib (mean age, 59 years ± 7.0 [standard deviation]; 11 men); 11 participants received pazopanib (mean age, 63 years ± 6.6; eight men). Responders had higher baseline tumor perfusion than nonresponders (mean, 404 mL/100 g/min ± 213 vs 199 mL/100 g/min ± 136; P = .02). Perfusion decreased from baseline to week 2 (-53 mL/100 g/min ± 31; P < .001), after cycle 2 (-65 mL/100 g/min ± 25; P < .001), and after cycle 4 (-79 mL/100 g/min ± 15; P = .008). Interval reduction in perfusion at those three time points was not associated with ORR (P = .63, .29, and .27, respectively) or PFS (P = .28, .27, and .32). Perfusion increased from cycle 4 to disease progression (51% ± 11; P < .001). Conclusion Arterial spin labeled perfusion MRI may assist in identifying responders to vascular endothelial growth factor receptor tyrosine kinase inhibitors and may help detect early evidence of disease progression in patients with metastatic renal cell carcinoma. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Goh and De Vita in this issue.

Characterizing T2 iso- and hypo-intense renal masses on MRI: Can templated algorithms improve accuracy?

PURPOSE: To assess if a templated algorithm can improve the diagnostic performance of MRI for characterization of T2 isointense and hypointense renal masses. METHODS: In this retrospective study, 60 renal masses with histopathologic diagnoses that were also confirmed as T2 iso- or hypointense on MRI were identified (mean ± standard deviation, range: 3.9 ± 2.5, 1.0-13.7 cm). Two semi-quantitative diagnostic algorithms were created based on MRI features of renal masses reported in the literature. Three body-MRI trained radiologists provided clinical diagnoses based on their experience and separately provided semiquantitative data for each components of the two algorithms. The algorithms were applied separately by a radiology trainee without additional interpretive input. Logistic regression was used to compare the accuracy of the three methods in distinguishing malignant versus benign lesions and in diagnosing the exact histopathology. Inter-reader agreement for each method was calculated using Fleiss' kappa statistics. RESULTS: The accuracy of the two algorithms and clinical experience were similar (70%, 69%, and 64%, respectively, p = 0.22-0.32), with fair to moderate inter-reader agreement (Fleiss's kappa: r = 0.375, r = 0.308, r = 0.375, respectively, all p < 0.0001). The accuracy of the two algorithms and clinical experience in diagnosing specific histopathology were also no different from each other (34%, 29%, and 32%, respectively, p = 0.49-0.74), with fair to moderate inter-reader agreement (Fleiss's kappa: r = 0.20, r = 0.28, r = 0.375, respectively, all p < 0.0001). CONCLUSION: Semi-quantitative templated algorithms based on MRI features of renal masses did not improve the ability to diagnose T2 iso- and hypointense renal masses when compared to unassisted interpretation by body MR trained subspecialists.

The utility of magnetic resonance imaging for noninvasive evaluation of diabetic nephropathy.

BACKGROUND: Noninvasive quantitative measurement of fibrosis in chronic kidney disease (CKD) would be desirable diagnostically and therapeutically but standard radiologic imaging is too variable for clinical usage. By applying a vibratory force, tissue shear wave stiffness can be measured by magnetic resonance elastography (MRE) that may correlate with progression of kidney fibrosis. Since decreased kidney perfusion decreases tissue turgor and stiffness, we combined newly available three-dimensional MRE shear stiffness measurements with MR arterial spin labeling (ASL) kidney blood flow rates to evaluate fibrosis in diabetic nephropathy. METHODS: Thirty individuals with diabetes and Stage 0-5 CKD and 13 control individuals without CKD underwent noncontrast MRE with concurrent ASL blood flow measurements. RESULTS: MRE cortical shear stiffness at 90 Hz was decreased significantly below controls in all CKD stages of diabetic nephropathy. Likewise, ASL blood flow decreased progressively from 480 ± 136 mL/min/100 g of cortical tissue in controls to 302 ± 95, 229 ± 7 and 152 ± 32 mL/min/100 g in Stages 3, 4 and 5 CKD, respectively. A magnetic resonance imaging (MRI) surrogate for the measured glomerular filtration fraction [surrogate filtration fraction = estimated glomerular filtration rate (eGFR)/ASL] decreased progressively from 0.21 ± 0.07 in controls to 0.16 ± 0.04 in Stage 3 and 0.10 ± 0.02 in Stage 4-5 CKD. CONCLUSIONS: In this pilot study, MRI with ASL blood flow rates can noninvasively measure decreasing kidney cortical tissue perfusion and, with eGFR, a decreasing surrogate filtration fraction in worsening diabetic nephropathy that appears to correlate with increasing fibrosis. Differing from the liver, MRE shear stiffness surprisingly decreases with worsening CKD, likely related to decreased tissue turgor from lower blood flow rates.

The Incidental Splenic Mass at CT: Does It Need Further Work-up? An Observational Study.

Purpose To evaluate whether an incidentally noted splenic mass at abdominal computed tomography (CT) requires further imaging work-up. Materials and Methods In this institutional review board-approved HIPAA-compliant retrospective study, a search of a CT database was performed for patients with splenic masses at CT examinations of the abdomen and chest from 2002 to 2008. Patients were divided into three groups: group 1, patients with a history of malignancy; group 2, patients with symptoms such as weight loss, fever, or pain related to the left upper quadrant and epigastrium; and group 3, patients with incidental findings. Patients' CT scans, follow-up examinations, and electronic medical records were reviewed. Final diagnoses of the causes of the masses were confirmed with imaging follow-up (83.9%), clinical follow-up (13.7%), and pathologic examination (2.4%). Results This study included 379 patients, 214 (56.5%) women and 165 (43.5%) men, with a mean age ± standard deviation of 59.3 years ± 15.3 (range, 21-97 years). There were 145 (38.3%) patients in the malignancy group, 29 (7.6%) patients in the symptomatic group, and 205 (54.1%) patients in the incidental group. The incidence of malignant splenic masses was 49 of 145 (33.8%) in the malignancy group, eight of 29 (27.6%) in the symptomatic group, and two of 205 (1.0%) in the incidental group (P < .0001). The incidental group consisted of new diagnoses of lymphoma in one (50%) patient and metastases from ovarian carcinoma in one (50%) patient. Malignant splenic masses in the incidental group were not indeterminate, because synchronous tumors in other organs were diagnostic of malignancy. Conclusion In an incidental splenic mass, the likelihood of malignancy is very low (1.0%). Therefore, follow-up of incidental splenic masses may not be indicated. © RSNA, 2018.

US LI-RADS: ultrasound liver imaging reporting and data system for screening and surveillance of hepatocellular carcinoma.

Ultrasound is the most widely used imaging tool for hepatocellular carcinoma (HCC) screening and surveillance. Until now, this method has lacked standardized guidelines for interpretation, reporting, and management recommendations [1-5]. To address this need, the American College of Radiology (ACR) has developed the Ultrasound Liver Imaging Reporting and Data System (US LI-RADS) algorithm. The proposed algorithm has two components: detection scores and visualization scores. The detection score guides management and has three categories: US-1 Negative, US-2 Subthreshold, and US-3 Positive. The visualization score informs the expected sensitivity of the ultrasound examination and also has three categories: Visualization A: No or minimal limitations; Visualization B: Moderate limitations; and Visualization C: Severe limitations. Standardization in ultrasound utilization, reporting, and management in high-risk individuals has the capacity to improve communication with patients and referring physicians, unify screening and surveillance algorithms, impact outcomes, and supply quantitative data for future research.

Utility of transabdominal ultrasound for surveillance of known pancreatic cystic lesions: prospective evaluation with MRI as reference standard.

OBJECTIVES: To prospectively assess the utility of transabdominal ultrasound in surveillance of known pancreatic cystic lesions (PCL) using same day MRI as reference standard. METHODS: In an IRB-approved study with written informed consent, patients with known PCL underwent pancreas US on same day as surveillance MRI. US was performed blinded to same date MRI results. Transverse (TR), antero-posterior (AP), cranio-caudal (CC), and longest any plane diameter, were measured for each PCL at US and MRI. Visualization was correlated with patient (weight, abdominal diameter, thickness of abdominal fat, sex) and cyst (location, size, internal complexity) factors. RESULTS: 252 PCLs evaluated in 57 subjects (39 females; mean age 67 (range 39-86) yrs). Mean maximum PCL diameter 8.5 (range 2-92) mm. US identified 100% (5/5) of cysts ≥3 cm; 92% (12/13) ≥2 and <3 cm; 78% (43/55) ≥1 and <2 cm; 35% (27/78) ≥5 mm and <1 cm; and 16% (16/101) <5 mm. US visualization correlated with PCL location (<0.0001), size (p < 0.0001), patient gender (p = 0.005), participation of attending radiologist (p = 0.03); inversely with patient weight (p = 0.012) and AP abdominal diameter (p = 0.01). CONCLUSION: Many PCLs are visualized and accurately measured at follow-up with transabdominal ultrasound. Visualization correlates with lesion size, location, patient sex, weight, and abdominal diameter.

Diagnostic yield and clinical impact of microbiologic diagnosis from CT-guided drainage in patients previously treated with empiric antibiotics.

PURPOSE: The purpose of the study was to evaluate diagnostic yield and the added value of culture results on the clinical management of patients empirically treated with antibiotics prior to CT-guided drainage. METHODS: This retrospective, HIPAA-compliant, IRB-approved study reviewed records of 300 consecutive patients who underwent CT-guided aspiration or drainage for suspected infected fluid collection while on empiric antibiotics (11/2011 to 9/2013) at a single institution. Patient imaging and clinical characteristics were evaluated by an abdominal imaging fellow and culture results, and patient management were evaluated by an infectious diseases fellow. RESULTS: After exclusion of 14/300 (4.6%) patients who were not on empiric antibiotics and 8/300 (2.6%) patients in which no culture was acquired, 278 patients (average age 55 ± 16 years; M:F ratio 54:46) constituted the final study cohort. Leukocytosis was present in 163/278 (59%), and fever in 65/278 (24%). The average collection size was 8.5 ± 4.2 cm with gas present in 140/278 (50%) of collections; median amount drained was 35 mL, and visibly purulent material was obtained in 172/278 (63%). 236/278 (85%) received drains and the remainder were aspirated only. Average time between initiation of antibiotics and start of the drainage procedure was 4.1 ± 6.4 days (median 1.7 days). Cultures were positive in 205/278 (74%) patients with a resulting change in management in 181/278 (65%) cases. The change in management included change of antibiotics in 71/278 (26%), narrowing the antibiotic regimen in 94/278 (34%), and cessation of antibiotics in 16/278 (6%). Multidrug-resistant bacteria were cultured in 53/278 (19%). Several factors were found to be statistically significant predictors of positive cultures: patient leukocytosis (sens 62%, spec 53%), gas in the collection on CT (sens 59%, spec 77%), purulent material aspiration (sens 76%, spec 76%), and presence of polymorphonuclear cells in the specimen. CONCLUSIONS: Despite predrainage antibiotic therapy, CT-guided drainage demonstrates a high yield of positive cultures and influences clinical management in the majority of patients.

Correlation between the size of incidental thyroid nodules detected on CT, MRI or PET-CT and subsequent ultrasound.

PURPOSE: The aim of this study was to assess the relationship between size of thyroid nodules at computed tomography (CT), magnetic resonance imaging (MRI) or positron emission tomography CT (PET-CT), and size at ultrasound. MATERIALS AND METHODS: We performed a retrospective review of thyroid ultrasound studies over a 2-year period. RESULTS: A total of 307 patients were included in the study. There was a statistically significant difference between the size of nodules measured on ultrasound compared with cross-sectional imaging (P < .001). American College of Radiology white paper recommendations would have decreased ultrasound referrals by 24% without any additional missed malignancies. CONCLUSION: Cross-sectional imaging underestimates the size of thyroid nodules; however, the difference is small and likely not clinically significant.

Measurement of pancreatic cystic lesions on magnetic resonance imaging: efficacy of standards in reducing inter-observer variability.

PURPOSE: The purpose of this study is to assess inter-observer variability in the measurement of pancreatic cystic lesions with MRI and to determine the impact of measurement standards. MATERIALS AND METHODS: In this IRB-approved, HIPAA-compliant study with waiver of informed consent, 144 MRI examinations, containing pancreatic cystic lesions measuring between 5 and 35 mm, were reviewed independently by two radiology attendings and two abdominal imaging fellows. Measurements were repeated by the same reviewers 12 weeks later after the introduction of measurement standards. Results were analyzed using within-subject standard deviation, intraclass correlation coefficient, and kappa. RESULTS: Prior to standardization, the within-subject standard deviation, showing measurement variability in each cyst, was 4.0 mm, which was reduced to 3.3 mm after introduction of measurement standards (p < 0.01). Overall inter-observer agreement, kappa, improved from 0.59 to 0.65 (p = 0.04). The frequency of all four reviewers agreeing on size category increased from 51% to 60%. The intraclass correlation coefficient increased from 0.81 to 0.86. CONCLUSIONS: There is significant and frequent inter-observer variability in the measurement of pancreatic cystic lesions with MRI which could affect clinical management. Implementation of measurement standards reduces measurement variability and aids in preventing erroneous reporting of growth and potentially unwarranted changes in management.

Effect of Stereotactic Body Radiotherapy on the Growth Kinetics and Enhancement Pattern of Primary Renal Tumors.

OBJECTIVE: The objective of our study was to assess the growth rate and enhancement of renal masses before and after treatment with stereotactic body radiotherapy (SBRT). MATERIALS AND METHODS: This retrospective study included all patients with renal masses who underwent SBRT during a 5-year period. Orthogonal measurements of renal masses were obtained on pre- and posttreatment CT or MRI. Pre- and posttreatment growth rates were compared for renal mass diameter and volume using the t test. Pre- and posttreatment tumor enhancement values were compared for tumors that underwent multiphasic contrast-enhanced MRI. RESULTS: Forty patients underwent SBRT for the treatment of 41 renal tumors: clear cell renal cell carcinomas (RCCs) (n = 16), papillary RCCs (n = 6), oncocytic neoplasms (n = 8), unclassified RCCs (n = 2), urothelial carcinoma (n = 1), and no pathologic diagnosis (n = 8). The mean maximum tumor diameter before treatment was 3.9 cm (range, 1.6-8.3 cm). Three hundred thirty-eight pre- and posttreatment imaging studies were analyzed: 214 MRI studies and 124 CT studies. The mean pre- and posttreatment lengths of observation were 416 days (range, 2-1800 days) and 561 days (83-1366 days), respectively. The mean pretreatment tumor growth rate of 0.68 cm/y decreased to -0.37 cm/y post treatment (p < 0.0001), and the mean tumor volume growth rate of 21.2 cm(3)/y before treatment decreased to -5.35 cm(3)/y after treatment (p = 0.002). Local control-defined as less than 5 mm of growth-was achieved in 38 of 41 (92.7%) tumors. The Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 showed progression in one tumor (2.4%), stability in 31 tumors (75.6%), partial response in eight tumors (19.5%), and complete response in one tumor (2.4%). No statistically significant change in tumor enhancement was shown (mean follow-up, 142 days; range, 7-581 days). CONCLUSION: Renal tumors treated with SBRT show statistically significant reductions in growth rate and tumor size after treatment but do not show statistically significant differences in enhancement in the initial (mean, 142 days) posttreatment period.

Volumetric Arterial Spin-labeled Perfusion Imaging of the Kidneys with a Three-dimensional Fast Spin Echo Acquisition.

RATIONALE AND OBJECTIVES: Renal perfusion measurements using noninvasive arterial spin-labeled (ASL) magnetic resonance imaging techniques are gaining interest. Currently, focus has been on perfusion in the context of renal transplant. Our objectives were to explore the use of ASL in patients with renal cancer, and to evaluate three-dimensional (3D) fast spin echo (FSE) acquisition, a robust volumetric imaging method for abdominal applications. We evaluate 3D ASL perfusion magnetic resonance imaging in the kidneys compared to two-dimensional (2D) ASL in patients and healthy subjects. MATERIALS AND METHODS: Isotropic resolution (2.6 × 2.6 × 2.8 mm(3)) 3D ASL using segmented FSE was compared to 2D single-shot FSE. ASL used pseudo-continuous labeling, suppression of background signal, and synchronized breathing. Quantitative perfusion values and signal-to-noise ratio (SNR) were compared between 3D and 2D ASL in four healthy volunteers and semiquantitative assessments were made by four radiologists in four patients with known renal masses (primary renal cell carcinoma). RESULTS: Renal cortex perfusion in healthy subjects was 284 ± 21 mL/100 g/min, with test-retest repeatability of 8.8%. No significant differences were found between the quantitative perfusion value and SNR in volunteers between 3D ASL and 2D ASL, or in 3D ASL with synchronized or free breathing. In patients, semiquantitative assessment by radiologists showed no significant difference in image quality between 2D ASL and 3D ASL. In one case, 2D ASL missed a high perfusion focus in a mass that was seen by 3D ASL. CONCLUSIONS: 3D ASL renal perfusion imaging provides isotropic-resolution images, with comparable quantitative perfusion values and image SNR in similar imaging time to single-slice 2D ASL.

A tissue phantom model for training residents in ultrasound-guided liver biopsy.

RATIONALE AND OBJECTIVES: The apprenticeship model for training of percutaneous liver biopsy has limitations, and costs of commercially available simulation models can be prohibitive. We created an inexpensive tissue phantom for liver biopsy simulation and evaluated the utility of this model for training radiology residents. MATERIALS AND METHODS: A bovine-porcine tissue phantom was devised as a simulation model and consisted of bovine liver with a porcine rib layer and inserted pimento olives simulating target lesions. Training sessions (a 20-minute didactic lecture and a 90-minute practice session) were offered to all residents in a diagnostic radiology residency. Effect of training was assessed by questionnaire before and after training. Level of knowledge of topics covered in the didactic session, confidence in technical skills, and anxiety level were evaluated on a five-point scale (1, poor to 5, excellent). RESULTS: Thirty-five of 38 residents received training on the models (~$40). Mean reported value score for training was 4.88/5. Improvement was greatest for knowledge of technique (2.3-4.1/5, P < .001) and knowledge of postprocedure care (2.2-4.1/5, P < .001). Technical confidence increased (2.4-3.8/5, P < .001) and anxiety related to performing liver biopsy improved (2.7-3.7/5, P < .001). Residents with no prior experience in liver biopsy (n = 21) had significantly greater increases in all categories than residents with prior experience (n = 14), except for knowledge about obtaining informed consent and anxiety levels. CONCLUSIONS: Utilization of an inexpensively created bovine/porcine liver biopsy simulation model was well perceived by radiology residents and can be used as an educational tool during residency.

Pemberton's sign: explained nearly 70 years later.

CONTEXT: Pemberton's sign is used to evaluate venous obstruction in patients with goiters. The sign is positive when bilateral arm elevation causes facial plethora. It has been attributed to a "cork effect" resulting from the thyroid obstructing the thoracic inlet, thereby increasing pressure on the venous system. According to some, the "cork effect" is caused by the thyroid descending into the thoracic inlet during arm elevation. According to others, the obstruction is due to elevation of the thoracic inlet against the thyroid. OBJECTIVE: We studied a 36-year-old man with a positive Pemberton's sign secondary to a goiter extending to the substernal region. DESIGN AND INTERVENTION: Clinical, biochemical, and radiological assessments were done. Magnetic resonance angiography of the neck was performed while the patient's arms were elevated and at his sides. After the imaging studies were completed, the patient underwent thyroidectomy. RESULTS: Magnetic resonance angiography demonstrated that there was no craniocaudal movement of the goiter relative to the thoracic inlet. However, the lateral aspect of the clavicle moved medially and inferiorly, obstructing the right external jugular vein and subclavian vein confluence. CONCLUSIONS: In the present case, we demonstrated that when eliciting Pemberton's sign, facial plethora and venous engorgement were due to the clavicles moving and compressing venous vasculature against the enlarged thyroid and not to a "cork effect." Rather, the clavicular motion observed during arm elevation could be compared to the movement of a "nutcracker" compressing major venous structures within a narrowed thoracic inlet against a relatively fixed and enlarged thyroid.

Imaging of liver transplant and its complications.

The role of diagnostic imaging in liver transplantation is reviewed with a focus on assessing for postoperative complications after adult orthotopic transplant. The normal postoperative appearance after liver transplant and imaging appearances of both vascular and nonvascular complications are discussed. The key role of Doppler ultrasound as the first-line imaging modality is highlighted.

Comparing costs of robotic, laparoscopic, and open partial nephrectomy.

UNLABELLED: Abstract Background and Purpose: Laparoscopic and robot-assisted partial nephrectomy (LPN and RPN) are common minimally invasive alternatives to open partial nephrectomy (OPN) for management of renal tumors. Cost discrepancies of these approaches warrants evaluation. We compared hospital costs associated with RPN, LPN, and OPN. PATIENTS AND METHODS: Costs were captured for 25 patients in each group who underwent RPN, LPN, or OPN at our institution between November 2008 and September 2010. Variable costs included operating room (OR) time, supplies, anesthesia, and inpatient care costs. Fixed costs included equipment purchase and maintenance. Impact of variable and fixed costs were estimated using sensitivity analysis. RESULTS: Overall variable costs were similar for RPN, LPN, and OPN ($6375 vs $6075 vs $5774, P=0.117, respectively). OR supplies contributed a greater cost for RPN and LPN than OPN ($2179 vs $1987 vs $181, P<0.0001, respectively), while inpatient stay costs were higher for OPN compared with LPN and RPN ($2418 vs $1305 vs $1274, P<0.0001, respectively). Sensitivity analysis of variable costs demonstrates that RPN and LPN can represent less costly alternatives to OPN if hospital stay for RPN and LPN is ≤2 days and OR time <195 and 224 minutes, respectively. Inclusion of fixed costs made OPN less expensive than LPN and RPN unless use of the robot increases and operative times are reduced. CONCLUSION: By minimizing OR time and hospital stay, RPN and LPN can be cost equivalent to OPN regarding variable costs. When including fixed costs, RPN and LPN were more costly than OPN, but equivalence may be possible with improvements in efficiency.

Pancreatic surgery: a multidisciplinary assessment of the value of intraoperative US.

PURPOSE: To assess the value of intraoperative ultrasonography (US) for different types of pancreatic surgery. MATERIALS AND METHODS: An institutional review board-approved, HIPAA-compliant retrospective review with waiver of informed consent was performed to evaluate all cases of pancreatic surgery with intraoperative US or laparoscopic US that occurred at a single institution during a 10-year period. Surgical notes, radiologic images, and clinical data for each surgical procedure and subsequent clinical course were reviewed by pancreatic surgeons and radiologists. Presumptive diagnosis, type of surgical procedure performed, and final pathologic data were recorded. A relative value score was established by consensus and assigned to each case with a grade of 0-3, which indicated the value of the intraoperative or laparoscopic US. The type of operation and pathologic data were compared in each of the value score groups. Categoric variables were compared by using either χ(2) or Fisher exact test. RESULTS: One hundred ninety-three intraoperative or laparoscopic US procedures were performed in 189 patients. Of the patients, there were 102 men and 87 women. The mean age was 57.8 years (range, 18-86 years). Intraoperative or laparoscopic US value scores were as follows: value score 0, 3.6%; value score 1, 11.9%; value score 2, 31.1%; and value score 3, 53.4%. The most common contribution that resulted in a high score (value score 3) was facilitation of technical performance of the surgery (n = 60). High value score was significantly associated with performance of pancreatitis-related surgery (P < .001). The surgical indication that most commonly resulted in a low value score of 0 or 1 was staging of pancreatic cancers. All cases that received a score of 0 occurred in the laparoscopic adenocarcinoma surgical setting (staging or pancreatic biopsy). CONCLUSION: Intraoperative or laparoscopic US can be a valuable procedure in multiple types of surgical procedures that involve the pancreas and shows clear patterns of value in the different types of surgery.

Complication rate of ultrasound-guided percutaneous cholecystostomy in patients with coagulopathy.

OBJECTIVE: The purpose of this article is to compare the complication rate for ultrasound-guided percutaneous cholecystostomy in patients with coagulopathy to the rate in patients with normal coagulation. MATERIALS AND METHODS: We performed a database search for patients who underwent ultrasound-guided percutaneous cholecystostomy from January 2000 through December 2010. Patients were divided into those with normal coagulation and those with coagulopathy, as documented by abnormal laboratory values (international normalized ratio ≥ 1.5 and platelet count ≤ 50 × 10(9)/L) or history of anticoagulant medication in the preceding 5 days. Medical records were reviewed, and complication rates and subsequent treatment was recorded. Statistical analysis was performed using the Fisher exact and chi-square tests. RESULTS: Two hundred forty-two patients underwent ultrasound-guided percutaneous cholecystostomy (132 men and 110 women; mean [± SD] age, 73.9 ± 15.9 years; range, 22-104 years). One hundred thirty-two patients were coagulopathic and 110 had normal coagulation. Major complications related to ultrasound-guided percutaneous cholecystostomy were rare (4/242 cases [1.7%]) and included hemorrhage requiring transfusion (n = 1), death directly related to the procedure (n = 1), sepsis related to the procedure (n = 1), and abscess or biloma formation (n = 1). All of these occurred in the group with normal coagulation. Fourteen additional deaths (5.8%) that occurred within 30 days of the procedure were related to comorbidities. Minor catheter-related complications (15/242 [6.2%]) were due to catheter dislodgement (n = 11 [4.5%]), failure of placement (n = 1 [0.4%]), and hemorrhage not requiring transfusion (n = 3 [1.2%]). Two of the minor hemorrhagic complications were seen in the coagulopathic group and one in the normal coagulation group (p = 0.599). CONCLUSION: There is no difference in the complication rate for ultrasound-guided percutaneous cholecystostomy in patients who are coagulopathic compared with those who have normal coagulation.