MRI and S‐MRCP findings in patients with suspected chronic pancreatitis: Correlation with endoscopic pancreatic function testing (ePFT)

Purpose:

To review magnetic resonance imaging (MRI) and secretin stimulated magnetic resonance cholangiopancreatography (S‐MRCP) findings of patients with suspected chronic pancreatitis and compare them with endoscopic pancreatic function testing (ePFT).

Materials and Methods:

MRI and S‐MRCP findings of 36 patients with clinically suspected chronic pancreatitis were reviewed. Baseline ductal changes, duodenal filling grades, and pancreatic duct caliber change (PDC) on S‐MRCP, mean values of pancreatic anteroposterior (AP) diameter, signal intensity ratio (SIR) between pancreas and the spleen on T1‐weighted fat saturated images, and arterial to venous (A/V) enhancement ratios were compared between groups of normal and abnormal pancreatic exocrine function determined by ePFT.

Results:

All patients (n = 24) with normal ePFT (HCO₃ >80 mEq/L) had grade 3 normal duodenal filling. Patients with abnormal ePFT (HCO₃ <80 mEq/L) (n = 12) had grade 1 (n = 1) and grade 2 (n = 11) diminished duodenal filling (P < 0.0001). PDC was 1.51 in the normal ePFT group versus 1.27 in the abnormal ePFT group (P = 0.01). No significant differences were found in terms of mean pancreatic AP diameter (21.8 vs. 19.8 cm), SIR (1.59 vs. 1.44), and A/V (1.08 vs. 1.01) between groups of normal/abnormal pancreatic exocrine function.

Conclusion:

Despite discrepancies between pancreatic exocrine function and the findings on standard MRI/MRCP, the S‐MRCP findings are comparable to ePFT in the evaluation of chronic pancreatitis. J. Magn. Reson. Imaging 2010;31:601–606. © 2010 Wiley‐Liss, Inc.     

Diagnostic value of magnetic resonance cholangiopancreatography in cholestatic jaundice

The aim of the study

To evaluate the diagnostic accuracy of magnetic resonance cholangiopancreatography in patients with cholestatic jaundice.

Patients and methods

Clinical, laboratory and investigational data were evaluated from 50 patients with cholestastic jaundice. MRCP findings were compared with ERCP or operative findings and appropriate clinical endpoints.

Results

The ERCP or operative findings and appropriate clinical endpoints revealed 23 patients with intra or extra hepatic biliary dilatation and 27 patients without intra or extra hepatic biliary dilatation. As regards the 23 patients with biliary dilatation, biliary dilatation was evident in 19 patients by U/S versus 23 patients by MRCP. ERCP was successful in 20 patients (87%) and was not done in three patients (13%). In cases of obstructive jaundice the sensitivity of MRCP was 100% versus 86% in choledocholithiasis and malignant detection, respectively p value <0.05.

Conclusion

MRCP is highly sensitive and specific for biliary dilatation and avoids the need for invasive imaging in most patients with cholestasis. MRCP permits reservation of ERCP to patients with a high probability of therapeutic intervention.     

Differentiation between organic stenosis and functional dyskinesia of the sphincter of Oddi with amyl nitrite-augmented quantitative hepatobiliary scintigraphy

Recurrent biliary pain after cholecystectomy is presumably due to sphincter of Oddi dysfunction (SOD). There is no ideal non-invasive test for SOD, and the diagnosis often relies on invasive procedures such as sphincter of Oddi (SO) manometry. Amyl nitrite-augmented quantitative hepatobiliary scintigraphy (QHBS) was performed on nine asymptomatic volunteers and 22 patients with SOD of biliary types I and II. Normal QHBS parameters were established in the asymptomatic volunteers. QHBS revealed a partial obstructive pattern in nine patients in whom SO stenosis was suspected and in 13 patients in whom SO dyskinesia was suspected. This obstructive pattern remained unchanged in the former group, but was completely relieved in the latter group of patients on amyl nitrite administration. In conclusion, amyl nitrite-augmented QHBS proved to be a useful non-invasive method in the diagnosis of SOD of biliary types I and 11 and permitted differentiation between organic stenosis and functional motor abnormalities of the SO. Correspondence to: L. Madácsy     

清醒状态下兔Oddi括约肌肌电活动检测模型的建立

目的：建立清醒状态兔Oddi括约肌（SO）肌电检测的动物模型,研究其肌电活动特征。方法：将成年家兔麻醉后,于胆囊底部置管一根;将十二指肠大乳头对系膜缘与间置的空肠袢远端吻合,空肠袢关闭后与胆囊内置管分别埋置于皮下,恢复14d后用环状电极进行清醒状态下SO肌电检测。对其消化间期、进食后、外源性胆囊收缩素（CCK）泵注下SO肌电幅值、频率及每分钟运动指数进行分析。结果：利用该模型可以在清醒状态下稳定记录到SO肌电活动,表现为慢波恒定基础上快波的周期性变化,进食后SO的快波增强,外源性CCK对兔SO的肌电有兴奋作用。结论：清醒状态下SO肌电活动检测更能反映括约肌的功能状态,这为今后研究病理状态下SO的活动提供了技术平台。     

抑郁症相关执行功能障碍的磁共振成像研究进展

抑郁症患者常合并执行功能障碍,这种认知障碍会影响其日常生活质量及预后。执行功能需要额叶皮质、边缘系统、颞顶叶、丘脑、小脑、岛叶、脑干网状系统等协同作用,相应神经回路（主要包括默认模式网络、执行控制网络、突显网络和边缘系统）及其关键区域之间连接的破坏会导致执行功能的破坏。MRI可以非侵入性地显示大脑及其神经网络的结构和功能改变,识别抑郁症相关执行功能障碍及其治疗反应的异常表现,从而评估其功能背后相关的神经机制。笔者综述了目前抑郁症相关执行功能障碍的磁共振结构成像（包括弥散张量成像、形态结构成像）及功能成像的研究进展。     

High-resolution magnetic resonance imaging and conventional magnetic resonance imaging on a standard field-strength magnetic resonance system compared to arthroscopy in patients with suspected meniscal tears

RATIONALE AND OBJECTIVES: We sought to evaluate the diagnostic performance of high-resolution magnetic resonance imaging (MRI) and conventional MRI of the knee on a standard-field-strength MRI system compared to arthroscopic findings in patients with suspected meniscal tears. MATERIALS AND METHODS: Forty-two patients (20 women, 22 men), referred from the department of trauma surgery, with suspected medial meniscal tears and planned arthroscopy of the knee joint were included in the study. MRI was performed on a 1.0-T MRI scanner with two different protocols: (1) conventional MRI using a circular, polarized knee coil (coil diameter: 17 cm) with a sagittal dual fast spin-echo sequence (repetition time [TR]: 2500 ms; echo time [TE]: first, shortest, second, 120 ms; turbo spin echo [TSE] factor: 12; field of view: 180 mm; matrix: 256 x 512; scan percentage: 100; slice thickness: 3 mm) or (2) high-resolution MRI with a surface dual-loop coil of the medial knee compartment (temporomandibular joint, coil diameter: 8 cm) with a sagittal dual fast spin-echo sequence (TR: 2400 ms; TE: first, shortest; second, 120 ms; TSE factor: 12; field of view: 120 mm; matrix: 512 x 512; slice thickness: 2 mm). The menisci were evaluated on the basis of an adapted score (0 = normal meniscus, 1 = intrameniscal, T2-weighted hyperintense signal, 2 = discontinuity of the surface, 3 = fragmentation). Lesions that received a score of 2 or 3 were graded as meniscal tears. The MRI results were compared to the arthroscopic reports, which represented the gold standard, and the sensitivity of both protocols in detecting a meniscal tear was determined. RESULTS: Of the 42 patients included in the study, 25 (11 women and 14 men) underwent arthroscopy and all demonstrated a meniscal tear. A meniscal tear was correctly diagnosed in 76% of cases with conventional MRI and in 88% of cases with high-resolution MRI (P = .0087). CONCLUSION: High-resolution MRI, using a surface dual-loop coil and specific sequences, which can be performed on every standard-field-strength MRI scanner, is able to significantly improve diagnostic performance for the detection of a meniscal tear of the knee joint.     

静、动态MRI用于盆底功能障碍肛提肌评价的研究进展

盆底功能障碍是由于盆底支持结构薄弱所引起的包括盆腔器官脱垂、排尿及排便功能障碍等一系列症状的疾病。肛提肌是支持盆底的主要结构,静态MRI具有较高的软组织分辨力,能客观地评价肛提肌的形态及结构,动态MRI能实时反映肛提肌的运动及功能,为其全面评估提供客观依据。就静、动态MRI在盆底功能障碍中对肛提肌评价的应用及研究进展予以综述。     

Characterization of basal hepatic bile flow and the effects of intravenous cholecystokinin on the liver,sphincter, and gallbladder in patients with sphincter of Oddi spasm

The major objectives of this project were to establish the pattern of basal hepatic bile flow and the effects of intravenous administration of cholecystokinin on the liver, sphincter of Oddi, and gallbladder, and to identify reliable parameters for the diagnosis of sphincter of Oddi spasm (SOS). Eight women with clinically suspected sphincter of Oddi spasm (SOS group), ten control subjects (control group), and ten patients who had recently received an opioid (opioid group) were selected for quantitative cholescintigraphy with cholecystokinin. Each patient was studied with 111–185 MBq (3–5 mCi) technetium-99m mebrofenin after 6–8 h of fasting. Hepatic phase images were obtained for 60 min, followed by gallbladder phase images for 30 min. During the gallbladder phase, 10 ng/kg octapeptide of cholecystokinin (CCK-8) was infused over 3 min through an infusion pump. Hepatic extraction fraction, excretion half-time, basal hepatic bile flow into the gallbladder, gallbladder ejection fraction, and post-CCK-8 paradoxical filling (>30% of basal counts) were identified. Seven of the patients with SOS were treated with antispasmodics (calcium channel blockers), and one underwent endoscopic sphincterotomy. Mean (±SD) hepatic bile entry into the gallbladder (versus GI tract) was widely variable: it was lower in SOS patients (32%±31%) than in controls (61%±36%) and the opioid group (61%±25%), but the difference was not statistically significant. Hepatic extraction fraction, excretion half-time, and pattern of bile flow through both intrahepatic and extrahepatic ducts were normal in all three groups. Gallbladder mean ejection fraction was 9%±4% in the opioid group; this was significantly lower (P<0.0001) than the values in the control group (54%±18%) and the SOS group (48%±29%). Almost all of the bile emptied from the gallbladder refluxed into intrahepatic ducts; it reentered the gallbladder after cessation of CCK-8 infusion (paradoxical gallbladder filling) in all eight patients with SOS, but in none of the patients in the other two groups. Mean paradoxical filling was 204% (±193%) in the SOS group and less than 5% (P<0.05) in both the control and the opioid group. After treatment, six of the SOS patients had complete pain relief and one, partial pain relief. The basal tonus of the sphincter is variable in patients with SOS, and allows relatively more of the hepatic bile to enter the GI tract than the gallbladder. Due to simultaneous contraction of the sphincter and gallbladder in response to CCK-8, most of the bile emptied from the gallbladder refluxes into intrahepatic ducts, and reenters the gallbladder immediately after cessation of hormone infusion. The characteristic features of gallbladder filling, emptying, and paradoxical refilling with cholecystokinin provide objective parameters for noninvasive diagnosis of SOS by quantitative cholescintigraphy.     

Evaluation of results of the prostigmine-morphine test with quantitative hepatobiliary scintigraphy: a new method for the diagnosis of sphincter of Oddi dyskinesia

Attempts have long been made to use the prostigmine-morphine provocation test for the selection of postcholecystectomy patients suffering from sphincter of Oddi (SO) dyskinesia. Since the whole procedure is based upon the evaluation of subjective complaints, this test has frequently been criticized. To improve the diagnostic value of this method, we have visualized SO spasms during prostigmine-morphine provocation by means of quantitative hepatobiliary scintigraphy (QHBS). Twenty-two cholecystectomized patients with typical postprandial biliary pain were included in this study. In the first series of studies, QHBS with technetium-99m 2,6-diethylphenylcarbamoylmethyl-diacetic acid was performed in each patient 2 days before prostigmine-morphine provocation. The time to peak activity (T _max) and the half-time of excretion (T _1/2) over the liver parenchyma (LP), hepatic hilum (HH) and common bile duct (CBD), and the duodenum appearance time (DAT), were determined and served as control values. In the second series of experiments, sphincter spasms were evoked by prostigmine-morphine administration and visualized by means of QHBS. The same parameters were evaluated and serum levels of aspartate aminotransferase (AST) were determined simultaneously at regular intervals. In 12 patients who responded to prostigmine-morphine provocation with typical biliary pain and a significant AST elevation (Nardi positive group) the hepatobiliary scintigram demonstrated a marked biliary obstruction.T _max andT _1/2 over the LP, HH and CBD were significantly increased, while DAT was significantly longer relative to the corresponding data obtained without provocation. Four of the remaining ten patients indicated atypical abdominal pain during prostigmine-morphine provocation, but the AST level remained unchanged in all ten (Nardi negative group). In this group, QHBS revealed a slower, but free transpapillary flow of the tracer: althoughT _1/2 over the LP, HH and CBD appeared to be significantly higher than without provocation,T _max did not change and an obstructive pattern was not detected on the hepatobiliary scintigram. When QHBS parameters determined during prostigmine-morphine provocation were compared for the Nardi positive and Nardi negative groups, with the exception ofT _max over the LP they were significantly different. QHBS combined with the prostigmine-morphine provocation test proved to be a useful non-invasive method for the detection of pathological sphincter spasms in patients with SO dyskinesia. Application of this method is therefore strongly recommended in the diagnosis of SO dyskinesia.     

Initial experience with magnetic resonance fluoroscopy in the evaluation of oesophageal motility disorders. Comparison with manometry and barium fluoroscopy

The aim of this paper was to assess the diagnostic value of magnetic resonance (MR) fluoroscopy in the study of oesophageal motility disorders and to compare MR fluoroscopy results with those of manometry and barium contrast radiography. Twenty-five subjects referred for dysphagia and three patients in follow-up after pneumatic dilatation of the lower oesophageal sphincter to treat severe achalasia underwent esophageal manometry, barium contrast radiography and MR fluoroscopy. Examinations were performed on a 1.5 T scanner. Dynamic turbo- fast low angle shot (turbo-FLASH) sequences acquired during oral contrast agent administration were used to perform MR fluoroscopy. MR fluoroscopy correctly diagnosed achalasia in nine patients, uncoordination of esophageal body motility in ten and scleroderma oesophagus in one. Diagnostic performance was satisfactory, with a sensitivity of 87.5% and a specificity of 100% in the general depiction of motility alterations. Our work demonstrates that MR fluoroscopic examination in subject affected by oesophageal motility disorders is feasible and can properly depict motility and morphology alterations, achieving correct diagnosis in the majority of cases. Studies on larger populations are necessary to obtain statistically significant results.     

Dark-lumen magnetic resonance colonography in patients with suspected sigmoid diverticulitis: a feasibility study

To assess dark-lumen magnetic resonance colonography (MRC) for the evaluation of patients with suspected sigmoid diverticulitis. Forty patients with suspected sigmoid diverticulitis underwent MRC within 72 h prior to conventional colonoscopy (CC). A three-dimensional T1-weighted volumetric interpolated breath-hold examination sequence was acquired after an aqueous enema and intravenous administration of gadolinium-based contrast agents. All MRC data were evaluated by two radiologists. Based on wall thickness and focal uptake of contrast material and pericolic reaction including mesenteric infiltration on T1-weighted sequence the sigmoid colon was assessed for the presence of diverticulitis. MRC classified 17 of the 40 patients as normal with regard to sigmoid diverticulitis. However, CC confirmed the presence of light inflammatory signs in four patients which were missed in MRC. MRC correctly identified wall thickness and contrast uptake of the sigmoid colon in the other 23 patients. In three of these patients false-positive findings were observed, and MRC classified the inflammation of the sigmoid colon as diverticulitis whereas CC and histopathology confirmed invasive carcinoma. MRC detected additionally relevant pathologies of the entire colon and could be performed in cases where CC was incomplete. MRC may be considered a promising alternative to CC for the detection of sigmoid diverticulitis.     

Sincalide-augmented quantitative hepatobiliary scintigraphy (QHBS): definition of normal parameters and preliminary relationship between QHBS and sphincter of Oddi (SO) manometry in patients suspected of having SO dysfunction

Sphincter of Oddi (SO) dysfunction presents with vague abdominal pain and/or abnormal liver function tests, and is presumably due to SO stenosis or spasm. Clinical, laboratory, and imaging methods of diagnosis have been less than ideal. Initially, we determined normal quantitative hepatobiliary scintigraphy (QHBS) parameters both pre- and post-sincalide administration. Thirty-one "normals" were analyzed, and post-sincalide common bile duct (CBD) dynamics could be satisfactorily determined in 29 (94%) subjects. Normal values at sincalide-augmented QHBS are reported. Next, 10 patients suspected of having SO dysfunction were studied prospectively using SO manometry and QHBS. The two tests were in agreement in seven cases (4: normal CBD dynamics, 3: abnormal). In one case of advanced SO stenosis, QHBS was abnormal, but SO manometry could not be performed. In the two remaining cases, SO manometry and QHBS gave discordant results. Of greatest importance, no significant correlation existed between the quantitative parameters of these two tests. Sincalide-augmented QHBS is possible and may, in the future, be of value in the diagnosis of SO dysfunction and/or partial CBD obstruction.     

Post-cholecystectomy syndrome: hepatobiliary scintigraphy and cholangiopancreatography with magnetic resonance in 5 consecutive patients. Comparison of results and integrated diagnosis

PURPOSE: To investigate the clinical effectiveness of combined hepatobiliary scintigraphy (HBS) and MR-cholangiopancreatography (MRCP) studies in the postcholecystectomy syndrome. MATERIAL AND METHODS: June 1997, to February 1998, we examined with HBS and MRCP five women, three of them submitted to surgical and two to laparoscopic cholecystectomy. All patients had biliary pain but no changes in cholestasis and liver function blood parameters. After at least 4 hours' fasting HBS was performed dynamically, for one hour, injecting a 185 MBq 99mTc-mebrofenin bolus i.v. A fatty meal was given at the end of the basal test and serial static images were acquired till complete biliary washout. RESULTS: MRCP was normal in one case while in the others it showed biliary tree dilation, severe stricture of the distal common bile duct (CBD) and marked enlargement of the remnant cystic duct (RCD), which lodged a 6-mm stone in one patient. Pancreatic ducts were regular. HBS showed delayed biliary transit in all patients, which was however completed within 3 hours of injection, favored by the fatty meal. The RCD was not injected in three cases. Finally, HBS detected an early liver dysfunction in three cases. DISCUSSION: HBS and MRCP allow to evaluate the biliary tree function and anatomy, respectively, adding further data on liver function and pancreatic duct morphology. We detected associated functional and organic biliary alterations which were the likely cause of postcholecystectomy pain, such as severe spasm in Oddi's sphincter, nonpatent enlarged RCD and RCD stones. Moreover, HBS detected an early liver dysfunction in three cases. In conclusion, combined HBS and MRCP studies make a noninvasive, simple and accurate diagnostic approach in postcholecystectomy syndrome and for the screening of patients needing prompt surgical treatment.     

Comparison of automated 4-chamber cardiac views versus axial views for measuring right ventricular enlargement in patients with suspected pulmonary embolism

Purpose

Compare the right ventricle to left ventricle (RV/LV) diameter ratio obtained from axial pulmonary CT angiograms (CTPA) with those derived from automatically generated 4-chamber (4-CH) reformats in patients with suspected pulmonary embolism (PE).

Methods

In this institutional review board-approved study we included 120 consecutive non ECG-gated CTPA from 3 institutions (mean age 60 ± 16 years; 71 women). Twenty 64-slice CTPA with PE and 20 without PE were selected per institution. For each patient the RV/LV diameter ratio was obtained from both axial CTPA images and automatically generated 4-CH reformats. Measurements were performed twice in two separated sessions by 2 experienced radiologists and 2 residents. The differences between the measurements on both views were evaluated.

Results

The 4-CH view was successfully obtained in 113 patients. The mean axial and 4-CH diameter ratios were comparable for three of the four readers (p = 0.56, p = 0.13, p = 0.08). Although the mean diameters (1.0 and 1.03 respectively) for one resident were significantly different (p = 0.013), the difference of 0.03 seems negligible in clinical routine. Three readers achieved equally high intra-reader agreements with both measurements (ICCs of 0.94, 0.95 and 0.96), while one reader showed a different variability with ICCs of 0.96 for the axial view and 0.91 for the 4-CH view. The inter-reader agreement was equally high for both measurement types with ICCs of 0.95 and 0.94, respectively.

Conclusion

In patients with suspected PE, RV/LV diameters ratio can be measured with the same reproducibility and accuracy using an automatically generated 4-CH view compared to the axial view.     

Comparison of the clinical state and its changes in patients with Duchenne and Becker muscular dystrophy with results of in vivo 31P magnetic resonance spectroscopy

A total of 14 boys with the Duchenne and Becker forms of muscular dystrophy (DMD, BMD) were examined using ³¹P magnetic resonance (MR) spectroscopy; 12 boys were examined repeatedly. The results were correlated with clinical findings (including those of genetic tests) and with data obtained from examinations of an age-matched control group. Evaluation of results using principal component analysis revealed maximum variability in the following ratios: phosphocreatine/inorganic phosphate (PCr/Pi), phosphocreatine/phosphodiesters (PCr/PDe) and phosphocreatine/phosphomonoesters (PCr/PMe). A decrease in PCr/Pi correlates with weakness of the hip girdle and of the lower part of the shoulder girdle in DMD/BMD patients. The values of all ratios in the group of patients with the DMD phenotype differ significantly from results obtained in the group with the BMD phenotype. Continoous follow-up of patients using ³¹P MR spectroscopy revealed a marked decrease in PCr/Pi in DMD/BMD patients at an age that could be expected in subjects with a typical clinical course of DMD/BMD. An attempt to manage a concomitant disease with prednisone and carnitene was followed by an increase in PCr/Pi in 3 cases. A rise in the PCr/Pi ratio signalled clinical improvement in the patients. A decrease in PCr/Pi was found after controlled physical training, a finding consistent with data obtained from clinical observations describing an adverse effect of physical stress on the dystrophic process. Correspondence to: M. Hájek     

Comparison of the prognostic value of SPECT after nitrate administration and metabolic imaging by PET in patients with ischaemic left ventricular dysfunction

Purpose We compared the prognostic value of ^99mTc-tetrofosmin single-photon emission computed tomography (SPECT) after nitrate administration and positron emission tomography (PET) with ¹⁸F-fluorodeoxyglucose (FDG) in patients with ischaemic left ventricular (LV) dysfunction. Methods Eighty-nine patients with previous myocardial infarction and LV dysfunction (LV ejection fraction 33 ± 10%) underwent ^99mTc-tetrofosmin SPECT under control conditions (baseline) and after sublingual administration of 10 mg of isosorbide dinitrate (nitrate). Within 1 week, all patients underwent PET imaging with ¹⁸F-FDG. Four patients were excluded because of inadequate FDG uptake caused by severe diabetes. Follow-up data were obtained by phone contact with patients and by review of hospital or physicians’ records. Cardiac death, myocardial infarction and late revascularisation for unstable angina were considered as events. Follow-up data were not available in three patients. Follow-up was 96% complete at a mean period of 29 ± 19 months. Results At baseline SPECT, 59 (72%) patients had evidence of viable myocardium, while 23 did not. Of these latter patients, 12 (52%) demonstrated viable myocardium after nitrate and 13 (56%) had preserved metabolic activity. Cardiac events (cardiac death, myocardial infarction and late revascularisation for unstable angina) occurred in 24 (29%) patients. Event-free survival was similar in patients with and patients without viable myocardium at baseline SPECT (p = 0.8). In contrast, event-free survival was lower in patients with viable myocardium at nitrate SPECT and PET compared to those without viable myocardium (both p<0.05). Conclusion In patients with ischaemic LV dysfunction, the prognostic value of SPECT imaging after nitrate is comparable to that of PET metabolic imaging.     

Diagnostic accuracy of magnetic resonance imaging: a prospective evaluation of patients with suspected appendicitis (diamond)

Purpose:

To show the effect of standard magnetic resonance imaging (MRI) in patients with suspected appendicitis on negative laparotomy and perforation rate. Moreover, the economic impact on hospital resources was evaluated.

Materials and Methods:

In all, 52 patients (21 female; mean age 44.7 years) were prospectively included in this Institutional Review Board (IRB)‐approved study. Abdominal MRI including coronal inversion recovery, axial T2‐weighted, and contrast‐enhanced axial T1‐weighted sequences was performed. MRI results were compared to final clinical outcome determined by follow‐up or histopathology. Change of treatment was evaluated according to the final clinical outcome. Economic impact was evaluated by comparing the costs of MRI to the savings due to a change in treatment after MRI. Negative laparotomy and perforation rate as well as sensitivity and specificity were derived.

Results:

Negative laparotomy and perforation rate were 0% (0/52) and 8% (1/13). Sensitivity and specificity for detecting acute appendicitis were 85% (11/13) and 97% (38/39). In 40% of patients therapy changed due to the MRI. The overall effect on the use of hospital resources was a net saving of €2335.

Conclusion:

Abdominal MRI in the evaluation of patients with suspected appendicitis and equivocal clinical findings is safe, reliable, and cost‐effective. It should be considered an important alternative to computed tomography. J. Magn. Reson. Imaging 2012;35:617‐623. © 2011 Wiley Periodicals, Inc.