Magnetic resonance imaging of the female pelvis. New circularly polarized body array coil versus standard body coil.

RATIONALE AND OBJECTIVES: The authors compare the value of a new circularly polarized body array coil (BAC) system with a standard body coil (BC) for high-resolution magnetic resonance imaging of the female pelvis. METHODS: Twenty patients with cervical cancer were examined with a BC and BAC. Imaging parameters were kept constant (sagittal T2-weighted turbo spin-echo: repetition time = 4000 mseconds; effective echo time = 99 mseconds; 160 x 160 mm field of view; 256 x 256 matrix; 0.63 x 0.63 mm pixel size; 4-mm slice thickness). Images were scored for lesion-to-organ delineation and overall image quality/ artifacts using a scale from 5 to 1 (excellent to poor). Signal-to-noise (S/N) ratios for different tissues (tumor, uterus, vagina, rectum, muscle, and fat) as well as contrast-to-noise (C/N) ratios between tumor and (1) uterus, (2) vagina, and (3) rectum were calculated. Magnetic resonance tumor staging was performed according to the International Federation of Gynecology and Obstetrics (FIGO) classification. RESULTS: Using the BAC, S/N and C/N ratios increased significantly compared with the BC (S/N: 2.7-3.4-fold increase for all organs evaluated, P < 0.001: C/N: tumor versus uterus 2.4-fold, P < 0.01; tumor versus vagina 6.1-fold, P < 0.001; tumor versus rectum 3.1-fold, P < 0.01). This resulted in an improved overall image quality (average ratings: BAC-4.3 points; BC-2.6 points; P < 0.001). Lesion-to-organ delineation (average ratings: BAC 4.3-4.1 points, BC 3.5-2.7 points for all organs evaluated; P < 0.001) was increased noticeably on BAC images. No significant difference was found for staging accuracy. CONCLUSIONS: Circularly polarized BAC provide superior S/N and C/N ratios and improve lesion conspicuity compared with standard BC.

Immunoimaging of choroidal melanoma: assessment of its diagnostic accuracy and limitations in 101 cases.

Immunoscintigraphy (IS) was performed on 101 patients with space occupying intraocular lesions including choroidal melanomas (85), choroidal naevi (11), non-melanoma metastases (three), and other melanoma simulating lesions (two). Scintigraphic images with conventional and emission computer tomography techniques were obtained after the intravenous injection of 99mTc-labelled F(ab')2 fragments of monoclonal antibody (MoAb) 225.28S directed against the high molecular weight-melanoma associated antigen (HMW-MAA). Immunohistochemistry was performed on sections of four out of 10 melanoma-containing eyes to confirm MoAb binding. IS demonstrated positive scans in 66 out of 85 choroidal melanomas, offering a sensitivity of 78%. Sensitivity was dependent on the lesion size. True negative results were obtained in 15 out of 16 non-melanoma lesions (specificity 94%). False positive antibody accumulation was found in one patient with a post-traumatic subretinal haemorrhage. Immunohistochemistry demonstrated positive MoAb 225.28S binding in all melanoma sections. In summary IS offered substantial sensitivity and specificity in the differentiation of intraocular lesions, particularly choroidal melanomas, naevi, and metastases. In combination with other diagnostic procedures such as ultrasound echography and fluorescein angiography IS proved to be a valuable method in the diagnosis of choroidal melanoma.

MRI of the female and male pelvis: current and future applications of contrast enhancement.

Magnetic resonance imaging (MRI) of the pelvis has proven to be a most valuable diagnostic tool to examine pathologies of various organ systems in the pelvis. For most conditions MRI was found to be superior to other imaging modalities, like ultrasound and computed tomography. Controversy still exists on the value of intraluminal and intravenous contrast enhancement. This article gives an overview on currently available intraluminal and intravenous contrast agents. The techniques and results for contrast-enhanced MRI in the female and male pelvis are discussed based on a review of the literature. New developments and upcoming techniques, such as lymph node specific contrast agents and breathhold volumetric MRI, are described and initial results are presented.

The use of cold therapy after anterior cruciate ligament reconstruction. A prospective, randomized study and literature review.

We performed a randomized, prospective study to assess the effectiveness of postoperative cold therapy in patients who had anterior cruciate ligament reconstructions. Drain output, length of hospital stay, range of motion, and use of pain medication were all assessed. Patients were randomized into one of four groups after surgery. Group 1 patients had a cooling pad applied to the knee postoperatively and set at a temperature of 40 degrees to 50 degrees F, Group 2 had the cooling pad set at 70 degrees to 80 degrees F, Group 3 received ice packs, and Group 4 received no cold therapy of any kind. The skin temperatures in Groups 1 and 3 were significantly lower than the skin temperatures in Groups 2 and 4 (P < 0.001). The length of hospital stay, range of motion at discharge, use of oral and intramuscular pain medicine, and drain output were not significantly different between groups. No complications related to the type of cold therapy were seen in any group. Thus, both ice packs and cooling pads significantly decreased knee temperature, but we found no objective benefits in the early postoperative course due to this decrease in temperature.

[Parametrial infiltration of cervix carcinoma: diagnostic value of contrast-enhanced fat-suppressed T1-weighted SE sequences at 1.5 tesla]. / Parametrane Infiltration beim Zervixkarzinom: Diagnostische Wertigkeit von kontrastverstärkten fettsupprimierten T1-gewichteten SE-Sequenzen bei 1,5 Tesla.

PURPOSE: To determine whether contrast-enhanced and fat-suppressed sequences contribute to the MR imaging diagnosis of parametrial invasion. METHODS: 21 patients with carcinoma of the cervix were prospectively examined with a phased-array coil and a 1.5T MR-scanner using the following sequences: transverse T2-weighted turbo spin echo (T2-TSE), T1-weighted spin echo (T1-SE) and fat suppressed T1-weighted SE sequences before and after Gd-DTPA. The sequences were evaluated separately for the presence of parametrial invasion. Image quality and diagnostic confidence were classified on a scale of 0-10 (nondiagnostic-excellent). Findings were compared to the results of the pathohistological examination. RESULTS: Sensitivity, specificity and diagnostic accuracy were highest for T2-TSE sequences (100%, 79% and 86%, respectively). Contrast-enhanced T1-SE sequences with fat-suppression (71%, 79%, and 76%) showed no improvement compared to T2-TSE. Unenhanced fat-suppressed T1-SE (100%, 30%, and 56%) and unenhanced T1-SE (100%, 7%, and 38%) as well as contrast-enhanced T1-SE (86%, 20%, and 47%) were significantly worse than T2-TSE. With similar image quality (p < 0.05) diagnostic confidence was higher on T2-TSE than on any of the other sequences (p < 0.001). CONCLUSION: Considering the cost-effectiveness of the examination, for the MR diagnosis of parametrial invasion the use of fat-suppressed contrast-enhanced sequences can be abandoned in favour of T2-weighted TSE sequences.

[Lymph node staging in cervix carcinomas: the results of high-resolution magnetic resonance tomography (MRT) with a phased-array body coil]. / Lymphknotenstaging beim Zervixkarzinom: Ergebnisse der hochauflösenden Magnetresonanztomographie (MRT) mit einer Phased-Array-Körperspule.

PURPOSE: To determine the diagnostic value of high resolution MR imaging with a circularly polarised (c.p.) body phased-array coil for the staging of pelvic lymph nodes in cervical carcinoma. MATERIAL AND METHODS: 42 patients with histologically proven carcinoma of the cervix were studied on a 1.5 T scanner by using a c.p. body phased-array coil. The imaging protocol included T2-weighted turbo-spin-echo (TSE) and T1-weighted spin-echo sequences pre and post i.v. application of Gd-DTPA; slice thickness was 5-7 mm and pixel size 0.53 mm2. Lymph nodes with a diameter of > or = 8 mm were considered to have metastatic involvement. MR imaging results were compared with histopathologic findings. RESULTS: MR imaging showed enlarged lymph nodes (> or = 8 mm) in 16 of 18 patients with histologic proof of lymph node metastases (sensitivity 89%). In 22 of 24 cases MR findings were true negative (specificity 92%). Diagnostic accuracy was 91%. CONCLUSION: High-resolution MR imaging with a c.p. body phased-array coil provides high sensitivity, specificity, and diagnostic accuracy for pelvic lymph node staging in cervical carcinoma.

[Effects of biphasic spiral CT, conventional and iron oxide enhanced MRI on therapy and therapy costs in patients with focal liver lesions]. / Einfluss von biphasischer Spiral-CT, nativer und eisenoxidverstärkter MRT auf Therapie und Therapiekosten bei Patienten mit fokalen Leberläsionen.

PURPOSE: Evaluation of the diagnostic efficacy and cost-benefit of contrast enhanced CT (CT) and MRI pre- and post-SPIO-particles in focal hepatic disease with consideration of therapeutic outcome. METHODS: In 52 patients with the suspicion of primary or secondary hepatic malignancy, biphasic spiral CT and breath-hold gradient-echo T1- and fast spin-echo T2-weighted MRI pre- and post-iron oxide administration (1.5 T, body-phased-array coil) were compared. The number of hepatic lesions and the related diagnoses resulting from each imaging modality were recorded and statistically correlated to the final diagnoses established by biopsy/OP (34/52), long term follow-up of 12 months (18/52), and a consensus reading of all imaging modalities considering all clinical imaging information. The most likely induced therapy resulting from each imaging test was correlated to the final therapy. Based on data from the hospitals accountants, the therapy-related costs were estimated without hospitalization costs. RESULTS: In 34/52 (65.4%) of the cases the correct diagnosis was primarily stated by CT (sensitivity [se.] 85.2%, specificity [sp.] 44.0%). In additional 10/52 of the cases unenhanced MRI (se. 91.4%, sp. 75.0%) enabled correct diagnoses, and in another 6 cases the diagnosis was established only by SPIO-MRI (se. 100%, sp. 86.7%). Considering the possible therapeutic recommendation arising from each modality, CT would have induced needles therapy costs of 191,042 DM, unenhanced MRI of 171,035 DM, and SPIO-MRI of 7,311 DM. In comparison to the real therapy costs of 221,873 DM, this would have corresponded to an unnecessary increase of therapy costs of 86.1%, 77.1%, and 3.3%, respectively. In two cases (1 hemangioma, 1 regenerative nodule) all modalities failed, causing unnecessary surgery in one patient. DISCUSSION: In this problem-oriented scenario unenhanced and SPIO-enhanced MRI proved to be superior to CT regarding diagnostic efficacy. The cost-benefit resulted mainly due to preserving patients from unnecessary surgical procedures.

[MRI of plantar fasciitis]. / MR-Tomographie der Plantarfasciitis.

PURPOSE: The purpose of this study was to determine the type and frequency of characteristic bone and soft tissue changes on MRI of patients with a clinical diagnosis of plantar fasciitis. MATERIALS AND METHODS: 28 patients with a clinical diagnosis of plantar fasciitis underwent MR imaging. Besides T1- and T2-weighted sequences, short-tau-inversion-recovery sequences were used routinely. In 27 patients T1-weighted images after intravenous contrast injection were acquired additionally. As a control group the images of 15 patients without clinical signs for plantar fasciitis were evaluated. RESULTS: In 25 of 28 cases (89%) the clinical diagnosis of plantar fasciitis was established by MR imaging. The most common finding was a peritendinous edema at the calcaneal insertion site which was found in all 25 patients. In 19 of 25 cases (76%) a bone marrow edema of the calcaneus was present. In 14 of 25 cases (56%) an intratendinous signal intensity increase of the plantar fascia could be observed which showed contrast enhancement in 12 cases. Compared to the control group (mean thickness 3.3 mm) the plantar fascia showed significant thickening in the 25 MR positive patients (mean thickness 6.72 mm). DISCUSSION: Besides thickening of the plantar fascia and intratendinous signal intensity increase with contrast enhancement to some extent, bone marrow edema of the calcaneus and peritendinous edema close to the plantar fascia are characteristic signs of plantar fasciitis on MRI. Both signs can reliably be seen on STIR sequences only.

[Diagnostic value of different rectal contrast media in the detection of colorectal diseases by multi-slice CT]. / Diagnostische Wertigkeit verschiedener rektaler Darmkontrastierungen zur Erfassung von kolorektalen Erkrankungen im Multi-Detektor-CT.

PURPOSE: Assessment of 3 different rectal contrast agents (water, methylcellulose, ultrasound gel) for their suitability for colorectal imaging in multislice CT (MS-CT). METHODS: 115 patients with colorectal diseases underwent MS-CT with varying, rectal contrast agents in a prospective study. Images were assessed by 2 independent CT-experienced radiologists. 6 criterias were evaluated, using a 5-point scale. RESULTS: Methylcellulose (MC) proved to be significantly superior to ultrasound gel (US). Especially, differentiation of healthy and diseased bowel and bowel wall and lumen were aided, which was proven by quantitative analysis of attenuation values. Rectal distension is greater using MC or US than for water. More proximal parts of the colon could be better distended with water. The interobserver correlation was good (kappa 0.76). CONCLUSIONS: Rectal filling with MC significantly improves diagnostic confidence in colorectal examinations. Ease of administration and lack of problems suggest its use as a clinical routine tool.

Diagnostic approach in acute pulmonary embolism: perfusion scintigraphy versus spiral computed tomography.

For diagnosing acute pulmonary embolism, perfusion scintigraphy in combination with ventilation studies is a well-established and sensitive method. Recently, computed tomography (CT) incorporating an angiographic technique was introduced for evaluating the pulmonary arterial system without breathing artefacts. The present study compared lung scans with spiral CT data to establish the diagnostic value of the latter approach. Twenty-five patients with a clinical suspicion of acute pulmonary embolism were examined using both methods. Perfusion and ventilation lung scans were done and spiral volumetric CT studies were performed. In 18 patients, pulmonary embolism was diagnosed using both methods. However, the results were interpreted differently. Particularly when centrally localized emboli were present in both pulmonary arteries, assessment of the more affected side was difficult on CT and depended on the experience of the physicians interpreting the scans. Small, (sub-)segmental emboli could not be demonstrated on CT. This may explain the false-positive and false-negative results, respectively. Spiral CT enables an exact demonstration of thrombosis in severe, centrally localized emboli. In incompletely occluded vessels, estimation of the degree and the location of perfusion defects is better with scintigraphy. Based on the present results and the technical equipment necessary for spiral CT, it is concluded that perfusion scintigraphy remains the method of choice for diagnosing acute pulmonary emboli.

Case-oriented computer-based-training in radiology: concept, implementation and evaluation.

BACKGROUND: Providing high-quality clinical cases is important for teaching radiology. We developed, implemented and evaluated a program for a university hospital to support this task. METHODS: The system was built with Intranet technology and connected to the Picture Archiving and Communications System (PACS). It contains cases for every user group from students to attendants and is structured according to the ACR-code (American College of Radiology) 2. Each department member was given an individual account, could gather his teaching cases and put the completed cases into the common database. RESULTS: During 18 months 583 cases containing 4136 images involving all radiological techniques were compiled and 350 cases put into the common case repository. Workflow integration as well as individual interest influenced the personal efforts to participate but an increasing number of cases and minor modifications of the program improved user acceptance continuously. 101 students went through an evaluation which showed a high level of acceptance and a special interest in elaborate documentation. CONCLUSION: Electronic access to reference cases for all department members anytime anywhere is feasible. Critical success factors are workflow integration, reliability, efficient retrieval strategies and incentives for case authoring.

Diagnosis of osteomyelitis. Accuracy and limitations of antigranulocyte antibody imaging compared to three-phase bone scan.

Thirty-seven patients with suspected osteomyelitis in conjunction with diabetic gangrene (N = 14, group 1), arthroplasty (N = 8, group 2), and various diseases (N = 15, group 3) were examined. Three-phase bone scans, followed by granulocyte imaging using I-123 labeled anti-NCA 95 monoclonal antibodies, were performed to evaluate and compare the diagnostic accuracy of both procedures. Final diagnosis was established histologically, bacteriologically, or by both methods either through the clinical course or by long-term follow-up in patients in group 1. Osteomyelitis was proven in 17 out of the 37 patients. Bone and antigranulocyte imaging demonstrated positive results in all patients with osteomyelitis (sensitivity 100% for each method). No signs of skeletal infection were found in 20 patients. Fifteen of these patients had no antigranulocyte antibody accumulation, resulting in 75% specificity. Ten patients without infection had normal three-phase bone imaging results (specificity 50%). Antigranulocyte imaging results were negative in 6 out of 10 patients without osteomyelitis in groups 2 and 3 whose bone imaging results were questionable. However, because of identical bone and granulocyte imaging results, no increase of diagnostic accuracy could be obtained by additional granulocyte imaging in patients with diabetic gangrene. Final diagnoses of false-positive antigranulocyte studies were aseptic osteonecrosis (N = 2), loosening of prostheses, gouty arthritis, and pain after arthrolysis. In summary, antigranulocyte antibody imaging offered high sensitivity and acceptable specificity for the diagnosis of osteomyelitis. Diagnostic accuracy can be improved through the adjuvant use of antigranulocyte imaging for patients with suspected osteomyelitis, especially when radiographic and scintigraphic results are questionable or unreliable.

Diagnosis of prostate cancer in patients with persistently elevated PSA and tumor-negative biopsy in ambulatory care: performance of MR imaging in a multi-reader environment.

PURPOSE: False-negative results are obtained in approx. 20 % of prostate cancer (PCa) patients (pts) at initial systematic transrectal biopsy (Bx), in particular when digital rectal examination (DRE) or transrectal ultrasound (TRUS) is negative. The aim of this study was to assess whether MR endorectal imaging of the prostate in a multi-reader ambulatory care setting may assist in patient selection for re-biopsy. MATERIALS AND METHODS: 115 consecutive pts with persistent PSA elevation, negative Bx, DRE and TRUS were examined using T2w axial and coronal and T1w axial sequences for tumor diagnosis. MR images were prospectively read as tumor-suspicious or tumor-negative by the MR radiologist on duty. Additionally, a retrospective readout of a prostate MR expert and an abdominal imaging fellowship-trained radiologist was performed to evaluate the effect of the reader's experience on tumor detection. Imaging findings were compared to the results of the repeat Bx (61 pts) or the clinical course of at least two years. RESULTS: For the prospective reading, the sensitivity of MRI was 83 %, the specificity was 69 %, the PPV was 33 % and the NPV was 96 %. ROC analysis revealed a significantly better performance of the prostate MR imaging expert compared to the abdominal imaging radiologist (area under ROC 0.88 vs. 0.66, p < 0.001). Based on the prospective reading, a pre-test probability for PCa of 17.4 % as in our study can be reduced to 5 % when obtaining a tumor-negative result in MRI. CONCLUSION: MR imaging in a multi-reader ambulatory care setting assists in patient selection for re-biopsy. Reducing the post-test probability for PCa to 5 % allows for further follow-up instead of re-biopsy in MR tumor-negative patients. Specific training and experience improve tumor detection in prostate MR imaging.

[Herniation pits and their renaissance in association with femoroacetabular impingement]. / Herniation Pits und ihre Renaissance im Zusammenhang mit femoroazetabulärem Impingement.

Hernitation pits (HPs) of the femoral neck were first described in 1982. The purpose of this paper is to summarize the information concerning HPs published since then and to show their association with the diagnosis of femoroacetabular impingement (FAI) which has occurred within the last years. HPs are predominantly located at the anterior-superior femoral neck with a typical radiological appearance, which makes it possible to differentiate them from the numerous differential diagnoses mentioned. In the early publications HPs were described as a separate entity, while recent studies increasingly assign them to intra-osseous ganglia. In contrast to the early publications depicting HPs as an incidental finding, they are currently mainly mentioned in association with FAI and at the same time are partly considered to be a radiological indicator of FAI. In summary, HPs should always be recognized and documented because they may contribute to the diagnosis of FAI which is essential for preventing or delaying osteoarthritis of the hip joint in the early stage.

Combined MRI and MRS in prostate cancer: improvement of spectral quality by susceptibility matching.

PURPOSE: Local magnetic field inhomogeneity caused by susceptibility artifacts due to air in the endorectal coil substantially degrades the quality of 3D MR spectroscopic imaging (3D-MRSI). Perflubron (PFB) has magnetic susceptibility similar to that of human tissue. We prospectively assessed the effect of susceptibility matching using PFB on in vivo prostate (1)H-3D-MRSI. MATERIALS AND METHODS: Ninety-one consecutive patients referred for 3D-MRSI were examined using air and PFB as the filling agent for endorectal coils at 1.5T with an identically placed PRESS box and sat bands. Solely auto-shim without additional manual shimming was used. The full width at half maximum (FWHM) of the water peak was statistically compared with a paired t-test. The spectral quality was visually evaluated for the definition of metabolite peaks and for the citrate peak split (duplet). The MR image quality was rated on a five-point scale. RESULTS: FWHM was significantly less (p < 0.001) using PFB (mean 9.0 +/- 3.3, range 3 - 20) than air (mean 14.9 +/- 4.2, range 6 - 26) in 85/91 patients (93%). The spectral quality markedly improved using PFB and frequently the duplet of the citrate peak was able to be identified. Image quality ratings were similar (mean rating PFB 4.2, air 4.3 points). Omitting manual shimming led to a time savings of 4 min. per study. CONCLUSION: 3D-MRSI using PFB for susceptibility matching benefits from significantly better local field homogeneity, thus providing improved spectra quality. Combined with a substantial time savings in data acquisition, this may increase the clinical utilization of 3D-MRSI in patients with prostate cancer.

[Meniscus and ligament injuries]. / Meniskus- und Bandläsionen.

The knee is one of the major weight-bearing joints and is relatively exposed to trauma. Capsuloligamentous structures are essential to provide joint stability and -- in turn -- persistent instability bears a risk for osteoarthritis that needs timely and comprehensive diagnosis. Using MRI it may be beneficial to routinely apply (T)SE sequences in all three major planes as a basic protocol and to add additional sequences according to the clinical information available and imaging findings in the basic protocol. Especially fat-suppressed sequences (STIR, T2w/PDw FS TSE) are very useful because they sensitively depict bone marrow edema pattern (BMEP)-like changes. This finding often alerts the reader to -- sometimes only discrete -- underlying pathologies and may -- if found in typical locations -- give information about the mechanism of injury and thus lead the radiologist to look for specific concomitant capsuloligamentous, cartilage, and/or meniscal injury. BMEP is quite prominent in contusion injury, whereas often it is but discrete in avulsion lesions. There is extensive literature about the signs, possible pitfalls, and the accuracy of MRI for the diagnosis of specific pathologies such as meniscal tears or cruciate or collateral ligament ruptures. However, combined injuries of more than one structure are frequent and affect the therapeutic approach. Thus, the primary goal of the radiologist is to go beyond the description of any isolated lesion and to give a comprehensive description of (or to reliably exclude) any injury to other structures. A necessary prerequisite to accomplish this is a thorough knowledge of the -- in some locations -- complex anatomic relationships, pitfalls, and locations where lesions typically occur and where they may be overlooked.

[MR tomography in staging of carcinomas of the uterus]. / MR-Tomographie im Staging von Karzinomen des Uterus.

Magnetic resonance imaging (MRI) has proven to be a suitable imaging modality for the evaluation of uterine neoplasms. In contrast to computed tomography and ultrasound, MRI allows multiplanar observer-independent imaging of the whole female pelvis with high tissue-specific contrast. This article reviews the advantages and limitations of MRI in the staging of endometrial and cervical carcinoma, focusing on MRI with reference to other imaging modalities. New technical developments are discussed and an imaging approach for these tumor types is suggested.

[3-phase spiral CT--a new noninvasive procedure for the differentiation of multifocal liver lesions]. / Drei-Phasen-Spiral-CT--ein neues nichtinvasives Verfahren zur Differenzierung multifokaler Leberläsionen.

Dynamic CT is an established method for the differentiation of focal liver lesions by monitoring the contrast enhancement. It is especially restricted in the assessment of small and multiple lesions due to respiratory organ movements. Spiral-CT allows the examination of large volumes in the breathhold technique. Spiral-CT with controlled i.v. contrast media administration can be used for the assessment of the entire liver in distinct phases of perfusion. We describe the use of this new technique in a patient with multifocal nodular hyperplasia (FNH), for whom assessment with dynamic CT was not suitable. The lesions were first located with a conventional contrast-enhanced CT-scan. The impossibility to assess all the lesions with dynamic CT led to the decision to perform a three-phase spiral-CT with three sequential scans (native, arterial, and portal perfusion phase). The entire liver was scanned after power injector-controlled i.v. administration of contrast media with the following parameters: 1) arterial phase: 70 ml contrast media, 2 ml/s, start delay 18 s; 2) portal phase: 80 ml contrast media, 2 ml/s, start delay 60 s; slice 8 mm, table feed 8 mm, increment 4 mm; 24 s of breathhold data acquisition.

Computed tomography in pneumatosis intestinalis: differential diagnosis and therapeutic consequences.

Case reports of five patients with pneumatosis intestinalis diagnosed by computed tomography (CT) are presented. Etiology, differential diagnoses, and clinical consequences arising from CT imaging are discussed. In four of the patients, pneumatosis was found to be secondary to gastric ulcer, colon carcinoma, metastasis in the mesentery, and trauma-induced mesenteric ischemia. In one patient, the etiology remained elusive. Using CT, both the extent and the distribution pattern of pneumatosis could be depicted, allowing for differentiation of primary and secondary forms and assessment of prognosis. Evaluation with a lung window is a pre-requisite for reliable diagnosis of pneumatosis with CT. The presence of gas in the mesenteric or portal venous system in mesenteric ischemia is indicative of an unfavorable prognosis.