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.

Calcium score: semiautomatic calculation using different vendors versus fully automatic software.

OBJECTIVES: Recent advances in technology have resulted in a multitude of cardiac imaging postprocessing software products from vendors unrelated to the scanner on which the cardiac study was initially performed. A fully automatic calcium score software has also become available. We assess the intervendor variability of calcium score measurement using the semiautomatic software provided by the scanner vendor versus an unrelated vendor versus fully automatic software. METHODS: All consecutive patients who had a calcium score performed from March 2007 to January 2008 were included in this study. The studies were performed on two 64-slice computed tomographic scanners from 2 different vendors. The allocation of the patient to the specific scanner was done according to scanner and technologist availability. The studies were read twice by a cardiac radiologist and a general radiologist with at least 3 months' interval at a workstation specified by the computed tomographic scanner vendor and then at an unrelated workstation, with semiautomatic software. Calcium score was also independently performed by the fully automatic software, blinded to the results of previous readings. Agreement was tested with Pearson correlation coefficient, Bland-Altman graphs, and the Fleiss κ test. RESULTS: The study population included 101 patients: 70 patients scanned at 1 scanner and 31 at a different scanner. Intervendor variability for the 2 groups had κ = 0.98 ± 0.01 and κ = 0.96 ± 0.02; interobserver variability had κ = 1. Semiautomatic versus automatic variability showed κ = 0.88 to 0.94. CONCLUSIONS: Because of very strong agreement between the calcium score measurements obtained by semiautomatic and fully automatic software by different vendors, calcium score measurements can be performed robustly at vendor-specific software, nonrelated software, or fully automatic software.

In vivo determination of a modified heat capacity of small hepatocellular carcinomas prior to radiofrequency ablation: correlation with adjacent vasculature and tumour recurrence.

PURPOSE: To calculate a modified heat capacity (mHC) of small hepatocellular carcinomas (HCCs) in vivo during radio frequency ablation (RFA) and to determine if mHC correlates with tumour vascularity, adjacent vessels or local recurrence. PATIENTS AND METHODS: This study was IRB approved and informed consent was obtained from all patients. Before formal RFA, ambient HCC temperature and temperature 1 min after heating at constant wattage were measured in 29 patients. From temperature change and wattage, individual mHCs (joules required to increase tumour temperature by 1° Celsius) were calculated. Pre-RFA, three-phase computerised tomography (CT) scans were reviewed blindly for hepatic arteries, hepatic veins and portal veins abutting or within 3 mm of tumour edge from which twelve vascular parameters were quantified. Tumour enhancement (homogeneous or heterogeneous on arterial phase) was also assessed. Multiple regression was used to correlate mHC with vascular parameters and tumour enhancement. Cox proportional hazard model was used to examine the relationship of mHC to local recurrence. RESULTS: There was significant correlation of mHC with lesion enhancement (P = 0.0018), length of hepatic arteries (P < 0.0001) and total hepatic vein volume in contact with tumour (P = 0.016). No correlation was found with any non-abutting vessel or portal vein parameter. The chance of local recurrence increased with increasing mHC. CONCLUSION: Because the modified heat capacity of small HCCs in our study population correlated with HCC enhancement, abutting hepatic arteries, the volume of abutting hepatic veins and local recurrence, it may be an indicator of the heat sink effect (HSE) and supports the HSE as a risk factor for local recurrence.

Incidentally detected misty mesentery on CT: risk of malignancy correlates with mesenteric lymph node size.

OBJECTIVE: To determine the natural history of incidentally detected misty mesentery on computed tomography (CT) and to correlate the risk of malignancy with size of mesenteric lymph nodes. METHODS: A retrospective review of all CT abdomen/pelvic examinations from January 1, 2004 through December 31, 2008 identified cases of misty mesentery. The largest mesenteric lymph node was measured, and additional areas of lymphadenopathy were identified. Follow-up was obtained by reviewing all subsequent CT examinations, clinical notes, and pathologic specimens. Patients were excluded if they had a known malignancy at the time of initial CT, CT or clinical history revealing a cause for the misty mesentery, or CT follow-up of less than 2 years. RESULTS: Thirty-seven patients with misty mesentery were included. The mean time from the original CT to the latest follow-up was 3.8 years. The largest lymph node measured less than 10 mm in 30 (81%) of 37 patients. All 30 patients demonstrated stable lymph node size, had no other regions with lymphadenopathy, and none developed malignancy. The largest lymph node was 10 mm or greater in 7 (19%) of 31 patients. Three of these patients developed non-Hodgkin lymphoma, 2 of which had other areas of lymphadenopathy. No cases of nonlymphomatous malignancy were identified. CONCLUSIONS: The development of malignancy in patients with incidentally detected misty mesentery correlates with mesenteric lymph node size. Patients with misty mesentery and largest mesenteric lymph node less than 10 mm without additional areas of lymphadenopathy demonstrate a benign course, and no further follow-up may be necessary.

Incidentally detected gallbladder polyps: is follow-up necessary?--Long-term clinical and US analysis of 346 patients.

PURPOSE: To determine the natural history of gallbladder (GB) polyps incidentally detected at ultrasonography (US) and to propose management guidelines for these lesions based on polyp size. MATERIALS AND METHODS: The HIPAA-compliant study was approved by the institutional review board, and informed consent was waived. A database search for "polyp" in all US examinations of the GB between January 1, 1999, and December 31, 2001, at a single institution was performed. All subsequent US reports were reviewed to determine changes in GB polyp size. The electronic medical record was searched to obtain clinical and pathologic follow-up. RESULTS: Three hundred forty-six patients (mean age, 51.6 years; range, 20-93 years) with GB polyps were included. There were 156 men (45%) and 190 women (55%). US follow-up (mean, 5.4 years; range, 2-11.5 years) was performed in 149 patients (43%). Polyp size was stable in 90 (60%) polyps, decreased in eight (5%), increased in one (1%), and resolved in 50 (34%). Forty-two patients (12%) underwent cholecystectomy, revealing 13 (31%) GBs with polypoid lesions, 24 (57%) with stones and no polyps, and five (12%) with neither a stone nor a polypoid lesion. Clinical follow-up (mean, 8 years; range, 5-10.4 years) was performed in 155 patients (45%). No patient had clinical evidence of GB-related disease. Overall, no cases of GB malignancy were identified in 346 patients. Mean polyp size was 5.0 mm (range, 1-18 mm). No neoplastic polyps were found at 1-6 mm, one neoplastic polyp was seen at 7-9 mm, and two neoplastic polyps were found at 10 mm or larger. CONCLUSION: The risk of GB malignancy resulting from incidentally detected polyps is extremely low. Incidentally detected GB polyps measuring 6 mm or less may require no additional follow-up. Data are inconclusive regarding polyps 7 mm or greater, and further studies are warranted.

Efficacy of radiofrequency ablation in the treatment of small functional adrenal neoplasms.

PURPOSE: To evaluate the use of radiofrequency (RF) ablation as a primary treatment for symptomatic primary functional adrenal neoplasms and determine the efficacy of treatment with use of clinical and biochemical follow-up. MATERIALS AND METHODS: After obtaining institutional review board approval, the authors retrospectively evaluated images and medical records from 13 consecutive patients with symptomatic functional adrenal neoplasms (<3.2 cm in diameter) who underwent RF ablation during a 7-year period. There were six men and seven women with a mean age of 54.1 years (range, 42-71 years). Cross-sectional images, findings from clinical examination, and adrenal biochemical markers were available for all patients. Ten of the 13 patients (77%) had an aldosteronoma and one patient each had a cortisol-secreting tumor, testosterone-secreting tumor, and pheochromocytoma. RF ablation was performed by two radiologists using an internally cooled electrode and a pulsed technique according to manufacturer's specifications. Clinical and laboratory follow-up was performed for all patients. Three patients underwent imaging follow-up for other reasons. RESULTS: All patients demonstrated resolution of abnormal biochemical markers after ablation (mean biochemical follow-up, 21.2 months). In addition, all patients experienced resolution of clinical symptoms or syndromes, including hypertension and hypokalemia (in patients with aldosteronoma), Cushing syndrome (in the patient with cortisol-secreting tumor), virilizing symptoms (in the patient with testosterone-secreting tumor), and hypertension (in the patient with pheochromocytoma). For the patients with aldosteronoma, improvements in hypertension management were noted. The mean blood pressure before ablation was 149/90 mm Hg with a mean (±standard deviation) of 3.1 ± 0.6 blood pressure medications, and this decreased to 122/77 mm Hg at a mean of 2.8 months after ablation with 1.3 ± 0.9 medications (P < .001) and 124/75 mm Hg at a mean of 41.4 months. There were two minor complications: one small pneumothorax and one limited hemothorax, neither of which required overnight admission. There were two episodes of transient self-remitting procedural hypertension-one in a patient with aldosteronoma and one in the patient with a cortisol-secreting tumor; however, none of these patients required further therapy during overnight observation. CONCLUSION: RF ablation may be an effective, minimally invasive method for treating small functional primary adrenal tumors.

Can Doppler sonography discern between hemodynamically significant and insignificant portal vein stenosis after adult liver transplantation?

OBJECTIVE: The purpose of our study was to determine whether Doppler sonography, using a strict reference standard, can specifically identify hemodynamically significant portal vein anastomotic stenosis after liver transplantation in adults. MATERIALS AND METHODS: The duplex and color Doppler examinations of 13 consecutive adult patients who underwent portal venography for suspected portal vein stenosis after liver transplantation were retrospectively examined. Peak systolic velocity (PSV) and change in PSV (ΔPSV) along the portal vein were correlated with portal venography. Stenoses above 50% on the basis of strict venographic criteria were considered hemodynamically significant. The Doppler studies before and after intervention were also assessed. Fourteen randomly chosen subjects with transplants without suspicion of portal anastomotic stenosis acted as controls. RESULTS: Six patients had significant portal vein stenosis (> 50%) and seven had stenosis below 50%. PSV and ΔPSV were significantly greater for patients with > 50% stenosis in comparison with those with ≤ 50% stenosis and control subjects. Optimal threshold values for PSV and ΔPSV were 80 and 60 cm/s, respectively, with either value alone yielding sensitivity of 100% and specificity of 84% for significant stenosis. Threshold values also included cases of stenosis below 50%. Five of six patients with > 50% stenosis underwent stenting, with poststent PSV and ΔPSV significantly declining to match that of control subjects. Three of seven with stenosis below 50% had stents placed but no significant change in the Doppler examination. CONCLUSION: Doppler threshold criteria reliably exclude those without posttransplantation portal vein stenosis and have high sensitivity for detecting portal stenosis. However, these criteria cannot discern the extent of stenosis.

Feasibility of measurement of pancreatic perfusion parameters with single-compartment kinetic model applied to dynamic contrast-enhanced CT images.

PURPOSE: To examine the feasibility of measuring pancreatic perfusion parameters by using a single-compartment kinetic model applied to contrast material-enhanced computed tomographic (CT) images. MATERIALS AND METHODS: This study received institutional review board approval and was HIPAA compliant. Informed consent was waived. Eight subjects (four men, four women; median age, 40 years; range, 35-57 years), all potential renal donors with no pancreatic pathologic abnormalities, underwent abdominal CT imaging, which resulted in 30 10-mm-thick sections obtained at a single level. Imaging was a direct result of bolus timing employed for standard renal donor protocol; no additional imaging beyond what was clinically warranted was performed. Images were obtained every 3 seconds; scanning was initiated at the onset of contrast material administration. Region-of-interest measurements were obtained for the pancreatic body and the aorta to generate time-enhancement curves (TECs). A one-compartment model was applied by using the aortic and pancreatic TECs as the input and output functions, respectively. Pancreatic volumetric blood flow F(V), volume of distribution V(D), and blood transit time tau were determined. Modeled pancreatic TECs were generated and were compared with actual TECs for wellness of fit. RESULTS: Pancreatic F(V) values from the single-compartment model ranged from 0.961 to 6.405 min(-1) (mean, 3.560 min(-1) +/- 1.900 [standard deviation]). Volume of distribution V(D) ranged from 1.491 to 3.080 (mean, 2.383 +/- 0.638), while values of tau ranged from -3.090 to 6.436 seconds (mean, 0.481 second +/- 3.000). Modeled pancreatic TECs closely matched true pancreatic TECs for each subject, with R(2) values ranging from 0.840 to 0.959. CONCLUSION: A simple one-compartment kinetic model can be applied to contrast-enhanced images of normal pancreas to yield accurate pancreatic TECs, which attest to the perfusion parameters obtained. In addition to yielding volumetric blood flow similar to that of other models of tissue perfusion, two additional pancreatic perfusion parameters can be obtained. SUPPLEMENTAL MATERIAL: http://radiology.rsnajnls.org/cgi/content/full/2492080026/DC1.

Femoral-to-port through-and-through wire access to reestablish subcutaneous port function.

OBJECTIVE: Central venous catheter malfunction often results from fibrin sheath formation and is routinely addressed with thrombolytic therapy or mechanical stripping. Mechanical stripping from a distant access site such as a femoral vein is the only option for a subcutaneous port that has failed thrombolytic therapy. When a fibrin sheath has rendered the catheter tip inaccessible to snaring, catheter salvage cannot be achieved, requiring port exchange. We report two cases in which an inaccessible catheter tip was mobilized via advancing a wire through the port and through the catheter, allowing for successful snaring, mechanical stripping, and return of normal port function. CONCLUSION: Passage of a hydrophilic wire through a subcutaneous port and beyond the catheter tip is technically possible. The wire can be snared from a femoral access to achieve successful catheter stripping when direct catheter snaring is not possible.

Screening carotid sonography before elective coronary artery bypass graft surgery: who needs it.

OBJECTIVE: The purpose of this study was to determine whether selection criteria for performing carotid sonographic screening before elective coronary artery bypass graft surgery can decrease the number of negative examinations without overlooking patients with significant carotid disease. SUBJECTS AND METHODS: A history of peripheral vascular disease, a prior cerebrovascular event, smoking, diabetes, hypertension, cervical carotid disease, left main coronary disease, and patient sex were criteria prospectively gathered for 295 consecutive patients undergoing screening carotid sonography before elective coronary artery bypass surgery. Logistic regression modeling was used to determine if any single criterion or combination of criteria could be applied to decrease the number of screening examinations without sacrificing detection of significant (> or = 50% cross-sectional narrowing) carotid stenosis. RESULTS: Smoking, diabetes, hypertension, a previous cerebrovascular event, peripheral vascular disease, left main coronary artery disease, and a history of cervical carotid disease were associated with significant carotid disease (chi-square test) in our subject population. Logistic modeling showed that the probability of detecting significant carotid disease increases 2.98 times for each additional selection criterion present. Possessing at least one selection criterion would still yield 100% examination sensitivity while increasing specificity to 30.0%. CONCLUSION: Selection criteria should be applied when choosing patients for carotid sonographic screening before elective coronary artery bypass surgery. This approach would decrease the number of noncontributory examinations but would have little effect on the detection of significant carotid stenosis in this target population.

Diagnostic radiology of transjugular intrahepatic portosystemic shunts.

Transjugular intrahepatic portosystemic shunts (TIPS) are an effective method for treating the complications of portal hypertension. Specific indications for TIPS include secondary prevention of variceal bleeding and refractory ascites. The purpose of this review is to summarize the role of diagnostic radiology in the creation and assessment of TIPS, to highlight the complications that can occur post-TIPS, and to critically evaluate the literature regarding ultrasound evaluation of TIPS.

Critically compromised airway secondary to expanding esophageal mucocele.

Expanding mucocele is a known but rare complication of bypass and surgical exclusion of the thoracic esophagus. When functional esophageal mucosa secretes mucin into the blind esophageal loop, tissue expansion can cause mass effect on nearby structures. We report the case of a critically compromised airway secondary to a dilated esophageal mucocele initially managed with right thoracotomy, partial esophagectomy and mucosectomy. This was complicated by mucocele recurrence, which was successfully managed with computed tomography-guided drainage and absolute alcohol ablation of residual mucosa.

Restoration of patency in failing tunneled hemodialysis catheters: a comparison of catheter exchange, exchange and balloon disruption of the fibrin sheath, and femoral stripping.

PURPOSE: To compare median patency times after treatment of malfunctioning tunneled hemodialysis catheters by one of three techniques: over-the-wire catheter exchange (CE), fibrin sheath stripping (FSS) from a femoral vein approach, and over-the-wire catheter removal with balloon dilation of fibrin sheath (DFS) followed by catheter replacement with use of the same tract. MATERIALS AND METHODS: Retrospective study was conducted of 66 consecutive procedures performed over a period of 47 months for poor flow through tunneled hemodialysis catheters despite tissue plasminogen activator infusion trials (CE, n=33; FSS, n=18; DFS, n=15). Baseline parameters (time since initial catheter placement, number of previous catheter interventions, catheter access site, and patient age and sex) were recorded to identify possible pretreatment differences among groups. Outcome comparison was based on duration of adequate catheter function on dialysis during follow-up. RESULTS: No significant differences in baseline parameters were identified among the three groups (P>.05). Mean follow-up duration (67+/-89 days; range, 0-398 d) was similar among the three groups. The immediate technical success rate was 100%, and there were no complications. Cumulative catheter patency rates were 73% (CE), 72% (FSS), and 65% (DFS) at 1 month; 43% (CE), 60% (FSS), and 39% (DFS) at 3 months; and 28% (CE), 45% (FSS), and 39% (DFS) at 6 months. Median duration of patency was similar among groups (P=.60). CONCLUSIONS: All three therapies were equivalent in terms of immediate technical success, complication rates, and durability of catheter function during later follow-up. Hence, when one technique is chosen over another, factors other than the period of secondary patency should be considered, such as cost and patient and physician preference.

Small-bowel perfusion measurement: feasibility with single-compartment kinetic model applied to dynamic contrast-enhanced CT.

This study was institutional review board approved and HIPAA compliant. Informed consent was obtained from all patients. The purpose of the study was to prospectively examine the feasibility of measuring small-bowel quantitative blood flow by using motion-corrected, contrast-enhanced computed tomographic (CT) images and a single-compartment kinetic model. Seven patients underwent abdominal CT in which 40 10-mm-thick sections were obtained at a single level. Small-bowel images were obtained every 3 seconds after contrast agent administration. Automated application of regions of interest yielded time-enhancement curves for the bowel wall and the aorta. A one-compartment model was applied to each set of time-enhancement curves for determination of the small-bowel volumetric blood flow F(V), volume of distribution V(D), and blood transit time tau. F(V) was also calculated by using the first-pass method and gamma variate analysis for model validation. The F(V) values obtained by using the single-compartment model (mean F(V), 0.47 min(-1)) showed excellent linear correlation with those obtained by using the first-pass method (Pearson r = 0.80) and gamma variate analysis (Pearson r = 0.97). Mean V(D) and tau values were 2.86 (unitless) and 4.28 seconds, respectively. A one-compartment kinetic model can be applied to motion-corrected, contrast-enhanced small-bowel CT images to quantify perfusion.

Clinical and duplex US assessment of effects of sildenafil on cavernosal arteries of the penis: comparison with intracavernosal injection of vasoactive agents--initial experience.

PURPOSE: To prospectively evaluate the clinical response and hemodynamic changes in cavernosal arteries after oral administration of sildenafil without and with audiovisual sexual stimulation and to compare those responses with responses from intracavernosal injections of vasoactive agents. MATERIALS AND METHODS: Institutional review board approval and written informed consent were obtained. Thirteen consecutive patients (age range, 22-77 years; mean, 60.4 years) with erectile dysfunction were evaluated with clinical assessment and cavernosal duplex ultrasonography (US). The patients were examined at two sessions 3 weeks apart. First, each patient received 100 mg of sildenafil citrate orally and was examined 60 minutes later without any sexual stimulation. Each patient then underwent repeat clinical and duplex US assessment after audiovisual sexual stimulation. Three weeks later, the patients underwent identical clinical evaluation and duplex US after intracavernosal injection of a commercially available combination of papaverine, prostaglandin E1, and phentolamine. Clinical and duplex US data (ie, peak systolic velocity [PSV]) were examined by using the Wilcoxon signed rank test for matched pairs. RESULTS: At rest, the overall mean cavernosal artery PSV was 1.08 cm/sec and remained unchanged after intake of sildenafil without any audiovisual stimulation, with no clinical evidence of erection. With the addition of audiovisual sexual stimulation, eight (62%) of 13 patients had penile congestion or erection, and six (46%) had a PSV greater than 25 cm/sec. With intracavernosal injection of the combination of three drugs, all 13 patients achieved congestion or erection, and 10 (77%) had a PSV greater than 25 cm/sec. Both clinical and duplex US responses to intracavernosal injection were significantly greater than they were to sildenafil with audiovisual sexual stimulation (P = .04 and .003, respectively). CONCLUSION: Oral sildenafil with audiovisual sexual stimulation led to a significant clinical response and increment in blood flow in the cavernosal arteries. However, more patients responded to intracavernosal injection of the combination of three drugs than to sildenafil, and the clinical response was significantly better.

Percutaneous treatment of a gastrocutaneous fistula after gastrostomy tube removal.

Gastrocutaneous fistula formation is a potential complication resulting from nonsurgical gastrostomy or gastrojejunostomy tube removal. Limited success in conservative treatment has been achieved with either mechanical obstruction of the tract or pharmacologically based increase in gastric pH and improvement of gastric emptying. A case of successful conservative percutaneous treatment of a gastrocutaneous fistula with use of the sequence of initial tract de-epithelialization followed by direct tract sclerosis and mechanical obstruction is presented in this article.

Detection of active colonic hemorrhage with use of helical CT: findings in a swine model.

PURPOSE: To evaluate the feasibility of helical computed tomography (CT) as an imaging modality for depicting active colonic hemorrhage in a swine model. MATERIALS AND METHODS: Controlled extravasation of contrast material-enhanced blood (CEB) from 140 to 180 HU and at varying rates (0.3-1.0 mL/min) was performed during a 30-second period by using a microcatheter system placed within the descending colon of 14 swine. CEB was immediately followed by extravasation of unopacified blood at the same location and rate during serial helical CT imaging of the extravasation site. Region-of-interest analysis allowed quantification of the dilution of extravasated CEB as a function of time that was then modeled mathematically based on iodine mass and volume balances. Nonlinear least squares analysis was performed to optimize fitting of the model to experimental data, with a maximum regression value (R2) of 1.0 indicating a perfect fit. This model enabled the computer simulation of CT imaging of multiple combinations of bleeding rates and CEB attenuation to determine the sensitivity of helical CT for depicting active colonic bleeding. RESULTS: Sixteen swine examinations yielded 16 CEB dilution curves. An excellent fit of the model to each dilution curve was achieved, as indicated by a mean R2 value of 0.8402. Swine examinations alone showed that targeted CT could depict CEB as low as 111 HU extravasating at a rate of 0.3 mL/min. Simulations that were based on helical CT images with 5-mm collimation reconstructed every 3 mm and that used the model indicated bleeding rates below 0.4 mL/min are detectable, provided peak aortic enhancement reaches 100 HU. CONCLUSION: Conservatively, helical CT has the potential to depict active colonic hemorrhage at rates of 0.5 mL/min or less.