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This article will review the mechanisms of gunshot- and blast-related injuries, highlighting both similarities and differences in injury patterns and imaging evaluation with a focus on injuries of the chest, abdomen, and pelvis. Advances in the types of weapons and targets of terror-related attacks, as well as the use of body armor, have led to a change in frequency and distribution of both blast- and gunshot-related injuries, a sizable portion of which involves the chest, abdomen, and pelvis. This article reviews requisite knowledge required by both radiologists and surgeons to evaluate gunshot- and blast-related injuries in the twenty-first century.

Purpose Size-specific dose estimates (SSDEs) are the latest focus of interest among medical physicists studying radiation dose to the patient in computed tomography (CT). This study aims to make conversions from CTDIvol to SSDE and investigate the relationship between mean SSDE (SSDE) and central SSDE (SSDEcenter) values for pediatric patients of different age groups undergoing chest, abdomen, and pelvis scans. Methods In this retrospective study, we examined 105 consecutive pediatric CT exams of chest, abdomen, and pelvis (CAP) classified in 3 separate groups according to age: 0-5 years, 6-10 years, and 11-16 years. A MATLAB program was developed to determine SSDE values for each patient along 6 subregions: chest, abdomen, pelvis, chest and abdomen, abdomen and pelvis, and CAP. SSDE values derived over the slice at the center of each scan range (SSDEcenter) were also recorded. SSDE and corresponding SSDEcenter results were compared for each age group. Results Root mean square differences (RMSD) between SSDE and SSDEcenter values ranged between 0.13 mGy and 2.1 mGy through all groups and subregions, corresponding to 1.2% and 11%, respectively. Conclusion In pediatric CT exams involving CAP region, CTDIvol and the water equivalent diameter at the middle of the scan range can be used to provide a reasonable estimate of mean SSDE with an RMSD of 11% at most.

Background The main objective of this study was to compare detection rates of clinically significant thoracolumbar spine (TLS) fracture between computed tomography (CT) imaging of the chest, abdomen, and spine (CT CAP) and CT for the thoracolumbar spine (CT TL). Methods We retrospectively identified patients at our institution with a TLS fracture over a two-year period that had both CT CAP and reformatted CT TL imaging. The sensitivity of CT CAP to identify fracture was calculated for each fracture type. Results A total of 516 TLS fractures were identified in 125 patients using reformatted CT TL spine imaging. Overall, 69 of 512 fractures (13%) were missed on CT CAP that were identified on CT TL. Of those, there were no clinically significant missed fractures. Conclusions CT CAP could potentially be used as a screening tool for clinically significant TLS injuries.

We present a new image quality assessment method for determining whether reducing radiation dose impairs the image quality of computed tomography (CT) in qualitative and quantitative clinical analyses tasks. In this Institutional Review Board-exempt study, we conducted a review of 50 patients (male, 22, female, 28) who underwent reduced-dose CT scanning on the first follow-up after standard-dose multiphase CT scanning. Scans were for surveillance of von Hippel–Lindau disease (N = 26) and renal cell carcinoma (N = 10). We investigated density, morphometric, and structural differences between scans both at tissue (fat, bone) and organ levels (liver, heart, spleen, lung). To quantify structural variations caused by image quality differences, we propose using the following metrics: dice similarity coefficient, structural similarity index, Hausdorff distance, gradient magnitude similarity deviation, and weighted spectral distance. Pearson correlation coefficient and Welch 2-sample t test were used for quantitative comparisons of organ morphometry and to compare density distribution of tissue, respectively. For qualitative evaluation, 2-sided Kendall Tau test was used to assess agreement among readers. Both qualitative and quantitative evaluations were designed to examine significance of image differences for clinical tasks. Qualitative judgment served as an overall assessment, whereas detailed quantifications on structural consistency, intensity homogeneity, and texture similarity revealed more accurate and global difference estimations. Qualitative and quantitative results indicated no significant image quality degradation. Our study concludes that low(er)-dose CT scans can be routinely used because of no significant loss in quantitative image information compared with standard-dose CT scans.

Non-contrast chest CT scans are commonly performed while CT scans of the abdomen and pelvis are performed in a select subset of patients; those with limited renal function, an allergy to iodinated contrast, in the setting of suspected renal calculus, retroperitoneal hematoma, common duct calculus, abdominal aortic aneurysm with or without rupture, and in patients undergoing a PET-CT scan. In the absence of intravenous contrast, vascular structures may prove challenging to evaluate, yet their assessment is an important component of every non-contrast CT examination. We describe the key imaging features of both arterial and venous pathology, and review clues and common associated non-vascular findings, which can help the radiologist identify vascular disorders at non-contrast CT. Briefly, alternative imaging options are discussed.

To determine the frequency of acute traumatic findings in computed tomographic (CT) chest abdomen pelvis (CAP) examinations in patients with acute traumatic head and/or cervical spine injury and no evidence suggesting bodily injury.After institutional review board approval with a waiver of informed consent was obtained, a HIPAA-compliant retrospective study was performed. A review of the electronic medical records and dictated reports identified patients who met the following criteria: CT-documented acute head and/or cervical spine trauma, CT CAP performed at least 20 minutes after initial brain and/or cervical spine CT, and no evidence of bodily injury at physical examination or on initial plain radiographs. The types of head and/or cervical injury, as well as mechanisms of injury in these patients, were analyzed. The frequency of acute traumatic injury in the CT CAP examinations was also determined, and 95% confidence intervals were calculated.There were 115 patients who met the study criteria (average age, 67.3 years). Sixty-three (54.8%) patients were male. The average injury severity score was 9.3. No patients who met the criteria for this study were found to have an acute traumatic injury to the chest, abdomen, or pelvis. These 115 CT CAP examinations comprised 7.5% (115 of 1530) of all CT CAP examinations performed in the emergency department over the 15-month study period.CT CAP examinations rarely if ever reveal acute traumatic injury in patients who have experienced low-velocity trauma and have acute head and/or cervical spine trauma in the absence of evidence of bodily injury.

The purpose of this article is to present illustrative cases highlighting the value of fetal MRI as a problem-solving tool in evaluating anomalies of the fetal chest, abdomen, and pelvis that are being evaluated for fetal therapy.Fetal MRI is an increasingly valuable noninvasive tool for evaluating fetal anomalies in the age of fetal therapy. Although ultrasound remains the primary diagnostic imaging modality, MRI can provide additional information to assist parental counseling and patient care.

Purpose To determine distances between patient centroid and gantry isocenter during CT imaging of the chest, abdomen, and/or pelvis, and to evaluate differences based on patient gender, scan region, patient position, and gantry aperture. Materials and Methods A water phantom and an anthropomorphic phantom were imaged in the centered position in the CT gantry and at several off-centered positions. Additionally, data from 57,621 adult chest, abdomen, and/or pelvic CT acquisitions were evaluated. Data were analyzed with an analysis of variance using the centroid-to-isocenter data as the dependent variable and the other parameters as independent variables. Results The majority of patient acquisitions (83.7% (48271/57621)) were performed with the patient’s centroid positioned below isocenter (mean 1.7 cm below isocenter (SD 1.8 cm); range 12.1 cm below to 7.8 cm above isocenter). Off-centering in the x-axis was less severe (mean 0.01 cm left of isocenter (SD 1.6 cm)). Distance between centroid and isocenter in the y-axis did not differ as a function of sex but did differ based on scan region, patient position, and gantry aperture. Conclusion Off-centering is common during CT imaging and has been previously demonstrated to impact dose and image quality.

The subserous space is a large, anatomically continuous potential space that interconnects the chest, abdomen, and pelvis. The subserous space is formed from areolar and adipose tissue, and contains branches of the vascular, lymphatic, and nervous systems. As such, it provides one large continuous space in which many disease processes can spread between the chest, abdomen, and the pelvis.

In oncology, staging forms the basis for prognostic consideration and directly influences patient care by determining the therapeutic approach. Cross-sectional imaging techniques, especially when combined with PET information, play an important role in cancer staging. With the recent introduction of integrated whole-body PET/MRI into clinical practice, a novel metabolic-anatomic imaging technique is now available. PET/MRI seems to be highly accurate in T-staging of tumor entities for which MRI has traditionally been favored, such as squamous cell carcinomas of the head and neck. By adding functional MRI to PET, PET/MRI may further improve diagnostic accuracy in the differentiation of scar tissue from recurrence of tumors such as rectal cancer. This hypothesis will have to be assessed in future studies. With regard to N-staging, PET/MRI does not seem to provide a considerable benefit as compared with PET/CT but provides similar N-staging accuracy when applied as a whole-body staging approach. M-staging will benefit from MRI accuracy in the brain and the liver. The purpose of this review is to summarize the available first experiences with PET/MRI and to outline the potential value of PET/MRI in oncologic applications for which data on PET/MRI are still lacking.

Venous injuries as a result of blunt trauma are rare. Even though current protocols for multidetector computed tomography (CT) of patients with trauma are designed to evaluate primarily the solid organs and arteries, blunt venous injuries may nevertheless be identified, or at least suspected, on the basis of the multidetector CT findings. Venous injuries are associated with high morbidity and mortality rates. Diagnosis of a possible venous injury is crucial because the physical findings of a venous injury are nonspecific and may be absent. This article aims to make the radiologist aware of various venous injuries caused by blunt trauma and to provide helpful hints to aid in the identification of venous injuries. Multidetector CT technology, in combination with interactive manipulation of the raw dataset, can be useful in the creation of multiplanar reconstructed images and in the identification of a venous injury caused by blunt trauma. Familiarity with direct and indirect signs of venous injuries, as well as with examples of blunt traumatic venous injuries in the chest, abdomen, and pelvis, will help in the diagnosis of these injuries.

Computed tomography of the chest, abdomen, and pelvis (CTCAP) has become the mainstay of diagnosis in stable blunt trauma patients. The purpose of this study was to investigate whether standard CTCAP has adequate sensitivity to identify fractures of the scapula, clavicle, and humeral head to replace routine radiographs of the shoulder. A retrospective chart review was carried out from January 1, 2004, to December 31, 2007, at Morristown Memorial Hospital. Inclusion criteria were all shoulder fracture patients in our trauma registry who underwent both a CTCAP and plain radiographs of the injured shoulder. Data were collected for patient age, sex, Injury Severity Score, mechanism of injury, and fracture location. Sensitivity was calculated for each diagnostic modality as well as hospital costs and radiation dose of plain radiographs. A total of 374 charts were reviewed and 98 patients were included in the study with a total of 117 fractures. The sensitivity of trauma CTCAP for scapula fractures was 100 per cent, clavicle fractures 98 per cent, and humeral head fractures 100 per cent. The sensitivity of the shoulder series for scapula fractures was 60 per cent, clavicle fractures 85 per cent, and humeral head fractures 100 per cent. The plain radiographs added $298 in hospital charges and 0.191 mSv of radiation per patient. CTCAP is a sensitive tool for identifying fractures in the shoulder girdle. Therefore, CTCAP can replace the routine radiographs of the shoulder resulting in less total radiation exposure of the trauma patients. This also would lead to lower healthcare cost and better diagnostic workflow.

The technique factors and X-ray output from the X-ray units of three Nigerian hospitals were obtained and used to calculate doses delivered to patients during chest, abdomen, skull and neck examinations. DoseCal software was used to calculate the entrance skin dose (ESD) and effective dose (E) based on the values of technique factors employed. The result obtained for inter-hospital comparison showed wide variation of mean hospital ESD, from a factor of 1.3 for chest posteroanterior (PA) in hospital 2 (H2) to a factor of 63 for the same chest X-ray projection in hospital 1 (H1). A comparison of ESD obtained in this work with established reference doses in the United Kingdom (UK 2005 review), International Atomic Energy Agency (IAEA), Community of European Commission (CEC), Ghana and Sudan shows that the values of ESD obtained in H1 for five examinations; namely: chest (PA) and lateral (LAT), abdomen anteroposterior (AP) and skull (PA and LAT) are higher. In H2, the dose value for chest PA is about 50% higher than that of UK but comparable with CEC and less than IAEA and Ghanaian values. The dose values obtained in H3 chest PA are higher than UK, IAEA and CEC values but comparable with that of Ghana. For abdomen AP, the dose is a factor of 1.2 less than IAEA and CEC values but greater than the UK, Ghanaian and Sudanese values by a factor of 2.1, 1.2 and 4.5, respectively. Reference data for abdomen LAT and neck AP were not available for comparison. Higher effective doses are being delivered to patients in chest PA (H1 and H3) and abdomen AP (H1) when compared with the range of values reported in the literature. This trend is an indication that patients examined are at higher health risks.

Organ dose is essential for accurate estimates of patient dose from CT. To determine organ doses from a broad range of pediatric patients undergoing diagnostic chest–abdomen–pelvis CT and investigate how these relate to patient size. We used a previously validated Monte Carlo simulation model of a Philips Brilliance 64 multi-detector CT scanner (Philips Healthcare, Best, The Netherlands) to calculate organ doses for 40 pediatric patients (M:F = 21:19; range 0.6–17 years). Organ volumes and positions were determined from the images using standard segmentation techniques. Non-linear regression was performed to determine the relationship between volume CT dose index (CTDIvol)-normalized organ doses and abdominopelvic diameter. We then compared results with values obtained from independent studies. We found that CTDIvol-normalized organ dose correlated strongly with exponentially decreasing abdominopelvic diameter (R2 > 0.8 for most organs). A similar relationship was determined for effective dose when normalized by dose-length product (R2 = 0.95). Our results agreed with previous studies within 12% using similar scan parameters (e.g., bowtie filter size, beam collimation); however results varied up to 25% when compared to studies using different bowtie filters. Our study determined that organ doses can be estimated from measurements of patient size, namely body diameter, and CTDIvol prior to CT examination. This information provides an improved method for patient dose estimation.

Injuries involving the thoracic and lumbar (TL) spine in the setting of blunt trauma are not uncommon. At our institution, CT of the chest, abdomen, and pelvis (CT CAP) with dedicated reformatted images of the thoracolumbar spine (CT TL) is part of the standard work-up of patients following significant blunt trauma. The purpose of this study was to compare the detection rate of TL spine fractures on routine trauma CT CAP with reformatted CT TL spine images and determine whether these reformatted images detect additional fractures and if these altered patient management. The imaging records of 1000 consecutive patients who received blunt trauma protocol CT CAP with CT TL spine reformats were reviewed to determine identification of TL spine fracture in each report. Fracture type and location were documented. Of the 896 patients, 66 (7.4 %) had fractures of the TL spine identified on either CT CAP or CT TL spine. Of these 66 patients, 40 (60.6 %) had fractures identified on both CT CAP and CT TL spine and 24 (36.4 %) had fractures identified on CT TL spine images alone. Fourteen patients required treatment with surgery or bracing, 4 (28.6 %) of which had fractures identified on reformatted TL spine imaging only. In conclusion, a significant number of fractures are detected on TL spine reformats that are not identified on CT CAP alone, altering patient management in a few cases and suggesting that dedicated TL spine reformats should be a standard part of the work-up of blunt trauma patients.

IntroductionVolumecomputed tomography dose index(CTDIvol) does not contain any dose information regarding the patient size. Size specific dose estimates (SSDE) give more reliable results accounting for the patient size as well. This parameter uses CTDIvol and size dependent conversion factors (fDw) which are calculated by means of water equivalent diameter (Dw) of the patient cross section in every slice of image.PurposeTo develop software to automatically calculate SSDE and to assess the impact of variations in Dw along the z axis on SSDE for CT examinations of the torso in pediatric patients.Materials and methods55 consecutive CT exams of the combined chest, abdomen and pelvis (CAP) have been examined. SSDE has been calculated for 6 hypothetical scan ranges: chest alone, abdomen alone, pelvis alone, chest and abdomen, abdomen and pelvis, and CAP. Two methods were used in mean SSDE approach: (1) mean SSDE over each scan range; (2) SSDE value at the middle of the scan range.ResultsFor scan ranges 1 to 6, the average of the difference in maximal and minimal Dw accross patients was 3.7, 3.8, 2.6, 4.1, 4.4 and 4.5 cm. The mean SSDE values calculated using methods (1) and (2) were highly compatible, with root mean square differences of 0.4, 0.5, 0.3, 1.0, 1.5 and 0.7mGy or 3%, 4%, 2%, 7%, 10%, 5%.ConclusionUsing the mean CTDIvol and the water equivalent diameter at the middle of the scan range provides a reasonable estimation of patient dose in pediatric exams.

Malignant melanoma is an aggressive neoplasm that can involve virtually every organ system. This article provides a review of the various appearances on computed tomographic (CT) scans of melanoma involving the chest, abdomen, and musculoskeletal system. Specific emphasis is placed on the typical and atypical CT manifestations of disease as well as the similarity of these findings to those for other disease entities. The importance of accurate staging of melanoma is stressed.

This article illustrates the magnetic resonance (MR) technique and MR imaging (MRI) findings of various neoplasms in chest, abdomen, and pelvis in pregnant patients. MRI can provide useful information about characterization and staging of maternal neoplasms without exposing the fetus to ionizing radiation and can be considered as a first-line cross sectional imaging method as an adjunct to ultrasonography.

Numerous medical devices are used in the chest and fewer in the abdomen and pelvis. They are frequently seen on various radiological studies in daily practice. Knowing the specific name of the device is not important. However, knowing the proper positioning and function of the device is necessary. It is a duty of the reporting radiologist to recognize the malpositioning or breakage of a medical device and to inform the responsible physician promptly, since these complications can have undesirable consequences and sometimes a fatal outcome.

An Assessment of the effects of radiation and chemotherapy on the reconstruction of the chest, abdomen and pelvis. Procedures of particular interest in this reference include alloplastic reconstruction of chest wall deformities; direct closure, tissue expansion and grafting of the abdominal wall; as well as rectus abdominus muscle involvement in th