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Imaging findings in a fatal case of pandemic swine-origin influenza A (H1N1).

AJR Am J Roentgenol. 2009 Dec;193(6):1500-3

Authors: Mollura DJ, Asnis DS, Crupi RS, Conetta R, Feigin DS, Bray M, Taubenberger JK, Bluemke DA

OBJECTIVE: Although most cases of swine-origin influenza A (H1N1) virus (S-OIV) have been self-limited, fatal cases raise questions about virulence and radiology’s role in early detection. We describe the radiographic and CT findings in a fatal S-OIV infection. CONCLUSION: Radiography showed peripheral lung opacities. CT revealed peripheral ground-glass opacities suggesting peribronchial injury. These imaging findings raised suspicion of S-OIV despite negative H1N1 influenza rapid antigen test results from two nasopharyngeal swabs; subsequently, those results were proven to be false-negatives by reverse transcriptase polymerase chain reaction. This case suggests a role for CT in the early recognition of severe S-OIV.

PMID: 19933640 [PubMed - indexed for MEDLINE]

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Swine-origin influenza A (H1N1) viral infection: radiographic and CT findings.

AJR Am J Roentgenol. 2009 Dec;193(6):1494-9

Authors: Ajlan AM, Quiney B, Nicolaou S, Müller NL

OBJECTIVE: The objective of our study was to review the chest radiographic and CT findings in patients with swine-origin influenza A (H1N1) virus (S-OIV) infection. CONCLUSION: The most common radiographic and CT findings in seven patients with S-OIV infection are unilateral or bilateral ground-glass opacities with or without associated focal or multifocal areas of consolidation. On MDCT, the ground-glass opacities and areas of consolidation had a predominant peribronchovascular and subpleural distribution, resembling organizing pneumonia.

PMID: 19933639 [PubMed - indexed for MEDLINE]

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Chest radiographic and CT findings in novel swine-origin influenza A (H1N1) virus (S-OIV) infection.

AJR Am J Roentgenol. 2009 Dec;193(6):1488-93

Authors: Agarwal PP, Cinti S, Kazerooni EA

OBJECTIVE: This article reviews the chest radiographic and CT findings in patients with presumed/laboratory-confirmed novel swine-origin influenza A (H1N1) virus (S-OIV) infection. MATERIALS AND METHODS: Of 222 patients with novel S-OIV (H1N1) infection seen from May 2009 to July 2009, 66 patients (30%) who underwent chest radiographs formed the study population. Group 1 patients (n = 14) required ICU admission and advanced mechanical ventilation, and group 2 (n = 52) did not. The initial radiographs were evaluated for the pattern (consolidation, ground-glass, nodules, and reticulation), distribution, and extent of abnormality. Chest CT scans (n = 15) were reviewed for the same findings and for pulmonary embolism (PE) when performed using IV contrast medium. RESULTS: Group 1 patients were predominantly male with a higher mean age (43.5 years versus 22.1 years in group 2; p < 0.001). The initial radiograph was abnormal in 28 of 66 (42%) subjects. The predominant radiographic finding was patchy consolidation (14/28; 50%) most commonly in the lower (20/28; 71%) and central lung zones (20/28; 71%). All group 1 patients had abnormal initial radiographs; extensive disease involving > or = 3 lung zones was seen in 93% (13/14) versus 9.6% (5/52) in group 2 (p < 0.001). No group 2 patients had > 20% overall lung involvement on initial radiographs compared with 93% of group 1 patients (13/14). PEs were seen on CT in 5/14 (36%) of group 1 patients. CONCLUSION: Chest radiographs are normal in more than half of patients with S-OIV (H1N1) and progress to bilateral extensive air-space disease in severely ill patients, who are at a high risk for PE.

PMID: 19933638 [PubMed - indexed for MEDLINE]

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Cardiac CT in the assessment of acute chest pain in the emergency department.

AJR Am J Roentgenol. 2009 Aug;193(2):397-409

Authors: Bastarrika G, Thilo C, Headden GF, Zwerner PL, Costello P, Schoepf UJ

OBJECTIVE: The purpose of this article is to describe the current role of ECG-synchronized CT in the evaluation of patients with acute chest pain (triple rule-out) in the emergency department. We discuss clinical contexts of the chest pain algorithm, technical improvements that have enabled CT to attain its current role for this application, scan protocols and radiation considerations, the evidence base regarding diagnostic and prognostic performance, and initial data on the cost-effectiveness of this promising emerging test. CONCLUSION: Currently available evidence suggests that CT-based approaches with modern scan technology are safe, accurate, and potentially cost-saving, although large-scale clinical trials are needed to ascertain the precise role of CT in the evaluation of acute chest pain.

PMID: 19620436 [PubMed - indexed for MEDLINE]

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CT diagnosis of acute mesenteric ischemia from various causes.

AJR Am J Roentgenol. 2009 Feb;192(2):408-16

Authors: Furukawa A, Kanasaki S, Kono N, Wakamiya M, Tanaka T, Takahashi M, Murata K

OBJECTIVE: Acute mesenteric ischemia can be caused by various conditions such as arterial occlusion, venous occlusion, strangulating obstruction, and hypoperfusion associated with nonocclusive vascular disease, and the CT findings vary widely depending on the cause and underlying pathophysiology. The aim of this article is to review the CT appearances of acute mesenteric ischemia in various conditions. CONCLUSION: Recognition of characteristic CT appearances and the variations associated with each cause may help in the accurate interpretation of CT in the diagnosis of mesenteric ischemia.

PMID: 19155403 [PubMed - indexed for MEDLINE]

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CT angiography in the evaluation of acute pulmonary embolus.

AJR Am J Roentgenol. 2008 Aug;191(2):471-4

Authors: Costantino MM, Randall G, Gosselin M, Brandt M, Spinning K, Vegas CD

OBJECTIVE: The purpose of this study was to assess the appropriate use of CT angiography (CTA) in the diagnostic evaluation of acute pulmonary embolism (PE). MATERIALS AND METHODS: We reviewed a total of 575 CT angiograms obtained to evaluate for PE at a large level 1 trauma teaching hospital from January 2004 through March 2005. Various clinical settings were used for 267 inpatient (46%), 258 emergency department (45%), and 50 outpatient (9%) studies. We excluded CTA performed for other reasons, repeated CTA, and patient records with incomplete clinical data. On the basis of chart review in which the investigators were blinded to final diagnoses, pretest probability of PE according to the Wells criteria was retrospectively assigned to each patient. D-dimer values, when obtained, also were reviewed. The diagnosis of PE was based on final CTA reports. RESULTS: PE was diagnosed in 9.57% of 575 patients. Positivity rates by location were 32 (12%) of the 267 inpatients, 22 (8.5%) of the 258 emergency department patients, and one (2.0%) of the 50 outpatients. Three (< 1%) of the 575 patients had high probability of PE, even though 351 patients had gone directly to CTA. Of the other 572 patients, 158 (28%) had intermediate and 414 (72%) low probability of PE. In the high, intermediate, and low probability groups, two (67%), 24 (15%), and 29 (7%), respectively, of the patients had PE. A D-dimer assay was performed for 224 (39%) of the 575 patients. Thirty-nine (17%) of the 224 patients had normal results (< 0.5 microg/mL); 107 (48%), intermediate results (0.6-2.0 microg/mL); and 78 (35%), abnormal results (> 2.0 microg/mL). In the emergency department cohort, 151 (59%) of 258 patients underwent a D-dimer assay. Thirty-two (21%) of the 151 patients had normal results; 81 (54%), intermediate results; and 38 (25%), abnormal results. Only one patient with a normal D-dimer level and three patients with intermediate D-dimer levels had PE, the equivalent of 3% of each group. The number of CTA examinations ordered for patients with normal and intermediate D-dimer results was 146 (25% of the 575 total studies). Twenty-two (8%) of the 258 emergency department patients had PE, and clinical suspicion of PE was high for 11 (50%), intermediate for 10 (45%), and low for one (5%) of those patients. CONCLUSION: Our data showed suboptimal use of the Wells criteria and subjective overestimation of the probability of PE before ordering of CTA. Although a definitive acceptable PE positivity rate for CTA has not been established, the 10% yield represents overuse of CTA as a screening rather than a diagnostic examination.

PMID: 18647919 [PubMed - indexed for MEDLINE]

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The PREDICT study: a randomized double-blind comparison of contrast-induced nephropathy after low- or isoosmolar contrast agent exposure.

AJR Am J Roentgenol. 2008 Jul;191(1):151-7

Authors: Kuhn MJ, Chen N, Sahani DV, Reimer D, van Beek EJ, Heiken JP, So GJ

OBJECTIVE: The objective of the PREDICT (patients with renal impairment and diabetes undergoing computed tomography) study was to compare the incidence of contrast-induced nephropathy (CIN) after administration of low-osmolar (iopamidol 370, 796 mOsm/kg) or isoosmolar (iodixanol 320, 290 mOsm/kg) contrast medium in patients with diabetes and chronic kidney disease undergoing CT. SUBJECTS AND METHODS: Two hundred sixty-three patients with moderate to severe chronic kidney disease (estimated glomerular filtration rate [GFR] = 20-59 mL/min/1.73 m(2)) and diabetes mellitus were randomized to receive at least 65 mL of iopamidol 370 or iodixanol 320 for a CT procedure. Serum creatinine levels were measured at baseline and 48-72 hours after contrast administration. CIN was defined as an increase in the serum creatinine level after contrast administration of >or= 25% from the baseline level. The incidence of CIN in the total study population and the incidence of CIN in patients at increased risk for CIN were compared using Fisher's exact test. RESULTS: Two hundred forty-eight patients were included in the CIN analysis: 125 receiving iopamidol 370 and 123 receiving iodixanol 320. Study population demographics were comparable, as was baseline renal function (estimated GFR = 47.6 mL/min/1.73 m(2) for the iopamidol 370 group vs 49.9 mL/min/1.73 m(2) for the iodixanol 320 group; p = 0.16). Increases in the serum creatinine value of >or= 25% occurred in seven patients (5.6%) receiving iopamidol 370 and in six patients (4.9%) receiving iodixanol 320 (95% CI, -4.8% to 6.3%; p = 1.0). The mean serum creatinine change from the baseline level was 0.04 mg/dL in both groups (analysis of covariance, p = 0.80). In patients with a baseline serum creatinine value of >or= 2.0 mg/dL, baseline estimated GFR of <or= 40 mL/min/1.73 m(2), or those receiving > 140 mL of contrast medium, the incidence of CIN was low and comparable between the two study groups (p = 1.0 in all instances). CONCLUSION: The incidence of CIN in patients with diabetes and chronic kidney disease receiving IV contrast medium was not significantly different after CT using iopamidol 370 or iodixanol 320.

PMID: 18562739 [PubMed - indexed for MEDLINE]

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Colonic pseudoobstruction: CT findings.

AJR Am J Roentgenol. 2008 Jun;190(6):1521-6

Authors: Choi JS, Lim JS, Kim H, Choi JY, Kim MJ, Kim NK, Kim KW

OBJECTIVE: The purpose of this review was to define the imaging features of colonic pseudoobstruction and to describe the pathologic findings. CONCLUSION: Colonic pseudoobstruction can be diagnosed on the basis of CT findings that show extensive colonic dilatation without an obstructive lesion at the intermediate transitional zone or adjacent to the splenic flexure. Pathologic examination reveals that intramural ganglion damage has a high tendency to occur in cases of chronic colonic pseudoobstruction.

PMID: 18492902 [PubMed - indexed for MEDLINE]

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Liability of the sleep-deprived resident.

AJR Am J Roentgenol. 2008 Apr;190(4):845-51

Authors: Berlin L

PMID: 18356427 [PubMed - indexed for MEDLINE]

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Chemoembolization of hepatocellular carcinoma: patient status at presentation and outcome over 15 years at a single center.

AJR Am J Roentgenol. 2008 Mar;190(3):608-15

Authors: Brown DB, Chapman WC, Cook RD, Kerr JR, Gould JE, Pilgram TK, Darcy MD

OBJECTIVE: We report the outcome of the care of 209 patients with hepatocellular carcinoma with a focus on relevant scoring systems for predicting overall survival and time to progression and on changes in presentation status and outcome from 1991 to 2006. MATERIALS AND METHODS: Hepatic arterial chemoembolization was performed on 209 patients in 375 sessions. Disease status was evaluated with the Child-Pugh, Okuda, Cancer of the Liver Italian Program, and American Joint Committee on Cancer (AJCC) systems. Changes in status at presentation from 1991 to 2006 and change in overall survival period and time to progression were analyzed. RESULTS: Median and mean overall survival periods for the entire group were 376 and 574 +/- 61 days. Median and mean times to progression were 267 and 409 +/- 54 days. Forty-nine patients underwent liver transplantation a median of 143 days after chemoembolization. The median and mean overall survival times among patients not undergoing transplantations were 466 and 574 +/- 61 days. Okuda score (p < 0.0001) and AJCC stage (p = 0.014) were the best predictors of overall survival and time to progression, respectively. Patients with disease with an Okuda I score and in AJCC stage I or II had median and mean overall survival periods of 667 and 992 +/- 176 days and times to progression of 378 and 589 +/- 110 days. Clinical status at presentation, overall survival period (p = 0.64), and time to progression (p = 0.44) were unchanged from 1991 to 2006. The 30-day mortality was 3.2%. CONCLUSION: Patients treated with hepatic arterial chemoembolization for HCC in Okuda score I and AJCC stage I or II have more durable survival than previously reported in a U.S. population.

PMID: 18287429 [PubMed - indexed for MEDLINE]

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