Israel Medical Association Journal

Abstract

Background: Only a few studies have compared the accuracy of magnetic resonance enterography (MRE) and computed tomography enterography (CTE) in the diagnosis of Crohn's disease and its complications.

Objectives: To compare the sensitivity of MRE and CTE analysis in their ability to detect, sign-by-sign, 10 classical imaging signs of Crohn's disease.

Methods: The study group comprised 42 biopsy-proven Crohn's disease patients who underwent both CTE and MRE within an average period of 6 weeks. Agreement between the two modalities in detecting the 10 most significant radiological signs of CD was evaluated using the Kappa index. The sensitivity of MRE and CTE was calculated using a standard of reference composed of all the findings seen by CTE and/or MRE. We analyzed MRE and CTE sensitivity separately in two groups, according to the time interval between the examinations.

Results: Agreement between CTE and MRE was more than 70% in 8 of the 10 signs: mural thickening, phlegmon, stenosis, skip lesions, mucosal stratification, fistula, abscess, and creeping fat. The Kappa level of agreement values for CTE versus MRE varied between substantial for phlegmon and skip lesions; moderate for fistula, creeping fat, abscess and mural thickening; and fair for stenosis and dilatation. CTE detected more findings than MRE, except for creeping fat and fistula. There was no significant difference in the sensitivity of CTE and MRE in the two groups defined by the time interval (time < 1.5 and time > 1.5 months) except for detection of dilatation.

Conclusions: Almost all imaging signs of Crohn's disease were detected equally well by both modalities regardless of the time interval between examinations. We therefore consider MRE to be reliable for imaging and follow-up in patients with Crohn's disease who may need recurrent imaging.

Background: Medical evaluation of a suspected meniscus injury begins with a history-taking and physical examination. Suspected meniscus injuries not responding to treatment are usually sent for imaging to confirm the diagnosis before arthroscopy. Tc-MDP bone single photon emission computed tomography (SPECT) scan has been suggested as an alternative to magnetic resonance imaging (MRI) in evaluating suspected knee meniscus tears.

Objectives: To examine the accuracy of knee SPECT as a tool to identify meniscus tears versus that of MRI as compared to the gold standard of arthroscopy.

Methods: The Israel Defense Forces database for 2005 through 2009 was searched according to the key words knee MRI, knee SPECT and knee arthroscopy. We identified 330 subjects who had undergone both a single knee SPECT and a single knee MRI prior to knee surgery. The medical files of 193 of the 330 subjects were randomly selected for review. A comparison was made between the preoperative SPECT and MRI studies and the arthroscopic finding. The sensitivity, specificity and accuracy were calculated.

Results: The subjects’ age was 21.3 ± 3.9. The agreement between SPECT and arthroscopy was 0.14 for the medial meniscus and 0.29 for the lateral meniscus. The agreement between MRI and arthroscopy was 0.59 for the medial meniscus and 0.69 for the lateral meniscus. SPECT scan was found to be 61% sensitive, 54% specific and 58% accurate in detecting common knee pathology, whereas MRI was found to be 95% sensitive, 67% specific and 85% accurate.

Conclusions: Knee SPECT has a lower sensitivity, specificity and accuracy than MRI in evaluating meniscal injuries and its use can result in increased unnecessary surgery.

Objectives: To measure the tumor-to-breast volume ratio using MRI in order to assess whether there is a correlation between this ratio and the type of surgery selected (breast-conserving or mastectomy).

Methods: The volumes of the tumor and the breast and the tumor-to-breast volume ratio were retrospectively calculated using preoperative breast MRI in 76 patients who underwent breast-conserving surgery or mastectomy.

Results: Breast-conserving surgery (lumpectomy) was performed in 64 patients and mastectomy in 12. The average tumor-to-breast volume ratio was 0.06 (6%) in the lumpectomy group and 0.30 (30%) in the mastectomy group (P < 0.0001).

Conclusion: The tumor-to-breast volume ratio correlated with the type of surgery. As measured on MRI, this ratio is an accurate means of determining the type of surgery best suited for a given patient. It is recommended that MRI-determined tumor-to-breast volume ratio become part of the surgical planning protocol for patients diagnosed with breast cancer.

Background: Spinal epidural abscess (SEA) is a rare disease with a potentially devastating outcome, and a reported incidence traditionally estimated at 0.2–2 cases/10,000 hospital admissions. Since the implementation in October 2007 of a program to increase medical personnel’s awareness of SEA, we have documented a sharp increase in the incidence of SEA at our medical center

Objectives: To investigate the cause of the increased incidence of SEA.

Methods: All cases diagnosed with SEA during the period 1998–2010 were retrospectively reviewed. Cases diagnosed before 2007 were compared with those diagnosed thereafter.

Results: From January 1998 to October 2007 SEA was diagnosed in 22 patients (group A), giving an annual incidence of 0.14–0.6 cases per 10,000 admissions. During the period November 2007 to April 2010, 26 additional patients were diagnosed (group B), yielding an incidence of 0.81–1.7 cases per 10,000 admissions (P < 0.01). The two groups did not differ significantly in epidemiological, clinical or laboratory characteristics, or in the causative bacteria isolated.

Conclusions: The threefold rise in the incidence of SEA observed at a tertiary medical center in Tel Aviv since November 2007 was not explained by different host characteristics or by more virulent bacterial isolates. We suggest that heightened awareness of the clinical presentation and timely utilization of MR imaging has resulted in more cases being identified. 

Objectives: To present the feasibility and safety of DSMR in Israel.

Methods: Thirty patients with suspected or known CAD were studied. DSMR images were acquired during short breath-holds in three short axis views and four-, two-, and three-chamber views. Patients were examined at rest and during a standard dobutamine-atropine protocol. Regional wall motion was assessed in a 16-segment model and the image quality was evaluated using a four-point scale for the visibility of the endocardial border.

Results: In 28 patients (93.4%) DSMR was successfully performed and completed within an average of 55 ± 6 minutes. One patient could not be examined because of claustrophobia and another patient, who was on beta-blockers, did not reach the target heart rate. Image quality was excellent and there was no difference between the rest and stress images in short axis (3.91 ± 0.29 vs. 3.88 ± 0.34, P = 0.13, respectively) and long axis (3.83 ± 0.38 vs. 3.70 ± 0.49, P = 0.09, respectively) views. Segmental intra-observer agreement for wall motion contractility at rest and stress cine images was almost perfect (κ = 0.88, 95% confidence interval = 0.93–0.84, and κ = 0.82, 95% CI = 0.88–0.76) respectively. No serious side effects were observed during DSMR.

Conclusion: The present study confirms the feasibility, safety and excellent image quality of DSMR for the diagnosis of coronary artery diseases.