Management of pneumothoraces detected on chest computed tomography: can anatomical location identify patients who can be managed expectantly?

BACKGROUND: Pneumothorax (PTX) can be readily detected by computed tomography (CT) or ultrasound. However, management of PTX in hemodynamically stable patients remains controversial. STUDY OBJECTIVES: We sought to investigate whether a distinct anatomical distribution of PTX along prespecified chest zones as detected by CT can be described in patients with or without subsequent chest tube thoracotomy (CTT), thus potentially allowing the extended focused assessment with sonography for trauma (EFAST) ultrasound examination to guide PTX management. METHODS: We performed a retrospective review of chest CT scans performed in the emergency department (ED) of a Level I trauma center. CT scans were analyzed for PTX distribution according to a chest zone model. Medical records of subjects with PTX were reviewed for subsequent CTT. RESULTS: Of 3636 chest CT scans performed, 183 PTX (156 patients) were detected without CTT at the time of CT scan (69% male, mean age 42 years). Of these, 66 subjects (40%) underwent CTT; 43 chest tubes (63%) were placed in the ED, 9 (13%) during hospitalization and 9 (13%) in the operating room. Median time to CTT was 140 min (interquartile range 52-199). Initial hemodynamic parameters, need for surgery, and need for mechanical ventilation were similar in both groups (p > 0.05 for all). Anatomical distribution and size of PTX were similar in the two groups. CONCLUSION: Although the majority of patients with traumatic PTX could be managed conservatively, we did not identify a characteristic anatomical PTX pattern, which could identify subjects who may not require CTT.

Implementation of speech recognition in a community-based radiology practice: effect on report turnaround times.

PURPOSE: Large academic practices have reported important benefits with the implementation of speech recognition software (SRS). However, the applicability of these results has been questioned in the community hospital setting because of major differences in workflow. The aim of this study was to evaluate the impact of SRS on radiology report turnaround times (TATs) at a community-based hospital practice with no radiology training program. The secondary goal was to evaluate the impact of SRS on radiologist productivity. METHODS: SRS was implemented at a 150-bed community hospital between May 2011 and July 2011. Radiology report TATs and normalized radiologist productivity were determined during 5 months before and after SRS implementation. Median and 80th and 95th percentile report TATs were compared between the preimplementation and postimplementation periods. The trend in productivity was also assessed. RESULTS: Median and 80th and 95th percentile report TATs decreased multiple-fold between the preimplementation and postimplementation periods (median, from 24 to 1 hour; 80th percentile, from 60 to 10 hours; 95th percentile, from 165 to 33 hours; P < .0001). No significant trend in report TATs was appreciated beyond the initial implementation of the software, a sustained effect on TATs. Normalized radiologist productivity was stable throughout the study period. CONCLUSIONS: The implementation of SRS was associated with 24-fold improvement in the median radiology report TAT in a community hospital setting with no radiology trainees. Improvements were obtained without affecting normalized radiologist productivity.

Diagnostic errors in the evaluation of nontraumatic aortic emergencies.

Nontraumatic aortic emergencies (NTAE) are a complex and dynamic group of serious, potentially fatal conditions affecting the aorta. These entities most often present in the emergency department setting, and include aortic dissection, intramural hematoma, penetrating atherosclerotic ulcer, as well as aortic rupture and impending rupture. The radiologist plays a critical role in prompt diagnosis and evaluation since presenting signs and symptoms are often nonspecific. This article focuses on the potential sources of error in the imaging evaluation of patients presenting with NTAE.

Abbreviated MRI for patients presenting to the emergency department with hip pain.

OBJECTIVE: The objective of our study was to assess the diagnostic performance of two abbreviated hip MRI protocols--coronal STIR images only and coronal STIR with coronal T1-weighted images--as compared with a full hip MRI protocol in patients presenting to the emergency department (ED) with hip pain and negative radiographic findings. MATERIALS AND METHODS: The cohort included 385 patients (277 females, 108 males; mean age, 61 years; age range, 16-99 years) who underwent MRI within 1 month of negative radiographs obtained for ED evaluation of hip pain between January 2000 and March 2009. MR examinations were graded independently by two musculoskeletal fellowship-trained emergency radiologists for detection of fracture, avascular necrosis (AVN), and muscle injury in three subsets: coronal STIR images only; coronal STIR images and coronal T1-weighted images; and the full examination. RESULTS: MRI detected findings suspicious for fracture in 42% (162/385) of patients, for AVN in 9% (33/385), and for muscle injury in 35% (134/385). The sensitivity and specificity of STIR alone in raising concern for fracture was 99% (220/223) for both readers, with small incremental benefits of adding coronal T1-weighted images. For AVN, specificity was 100% (28/28) with STIR alone, but the addition of coronal T1-weighted images provided substantial benefit by increasing sensitivity from 85% (28/33) to 97% (32/33). For muscle injury, sensitivity and specificity exceeded 95% (128/134) for both abbreviated examinations. CONCLUSION: An abbreviated MRI protocol including coronal STIR and coronal T1-weighted images has high sensitivity and specificity for fracture, AVN, and muscle injury in ED patients presenting with hip pain and negative radiographs.

Simplified diagnostic algorithm for Lauge-Hansen classification of ankle injuries.

Ankle injuries occur in a predictable sequence, allowing a logical understanding of their classification once the injury mechanism is recognized. The Lauge-Hansen classification system was developed on the basis of the mechanism of trauma and is useful for guiding treatment. Three radiographic views of the ankle (anteroposterior, mortise, and lateral) are necessary to classify an injury with the Lauge-Hansen system. Two additional criteria are also necessary: the position of the foot at the time of injury and the direction of the deforming force. Because understanding the mechanism of trauma is fundamental to classifying the injury, three-dimensional movies were assembled for each classification, showing the sequence of ligament rupture and bone fractures that occurs with each type of traumatic mechanism. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.322115017/-/DC1.

Anatomical distribution of traumatic pneumothoraces on chest computed tomography: implications for ultrasound screening in the ED.

OBJECTIVES: We sought to assess the anatomical distribution of traumatic pneumothoraces (PTXs) on chest computed tomography (CT) to develop an optimized protocol for PTX screening with ultrasound in the emergency department (ED). METHODS: We performed a retrospective review of all chest CTs performed in one ED between January 2005 and December 2008 according to presence, location, and size of PTX. Pneumothoraces were then measured and categorized into 14 anatomical regions for each hemithorax. RESULTS: A total of 277 (3.8%) PTXs were identified, with 26 bilateral PTX, on 3636 chest CTs performed during the study period. Etiology was blunt (85%) or penetrating trauma (15%). Eighty-three (45%) PTXs were radiographically occult on initial chest x-ray. One hundred eighty-three (66%) PTX had no chest tube at the time of CT. For both hemithoraces, the distribution demonstrated increasing PTX frequency and size from lateral to medial and from superior to inferior. Region 12 (parasternal, intercostal spaces [ICS] 7-8) was involved in 68% of PTX on either side; region 9 (parasternal, ICS 5-6), in 67% on the left and in 52% on the right; and region 11 (lateral to midclavicular line, ICS 7-8), in 46% on the left and in 53% on the right. The largest anterior-to-posterior PTX dimension was seen in region 12. CONCLUSIONS: Our results indicate that 80.4% of right- and 83.7% of left-sided traumatic PTXs would be identified by scanning regions 9, 11, and 12. These findings suggest that a standardized protocol for PTX screening with ultrasound should include these regions.

Outside imaging in emergency department transfer patients: CD import reduces rates of subsequent imaging utilization.

PURPOSE: To test the hypothesis that among emergency department (ED) transfer patients, CD import of outside examinations into the picture archiving and communication system (PACS) decreases imaging utilization in the subsequent 24 hours. MATERIALS AND METHODS: Institutional review board approval was obtained for this HIPAA-compliant study, with waiver of informed consent for retrospective medical records review. In 1487 consecutive ED patients, CD import to PACS was attempted between February 1 and August 31, 2009. Subsequent rates of imaging performed within 24 hours of any CD import attempt were extracted from the electronic medical record and compared between two patient groups: those with successful CD import and those for whom CD import had failed. Rates of all subsequent imaging and of computed tomographic (CT) imaging alone were compared by using the Wilcoxon rank sum test. ED CT utilization in the successful-import group was compared with that in a historical control group of 254 consecutive ED patients transferred with outside hospital CDs between August 2007 and January 2008, prior to implementation of import procedures. RESULTS: CD import to PACS was successful in 78% (1161 of 1487) of patients. Successful CD import produced a 17% reduction (P < .001) in mean rates of all subsequent diagnostic imaging, from 3.30 to 2.74 examinations per patient in the failed-import and successful-import groups, respectively, and a 16% reduction (P = .01) in subsequent CT utilization from mean of 1.41 to 1.19 scans per patient in those respective groups. Compared with the historical control group, posttransfer utilization of CT in the ED was reduced by 29% (P < .001) from 1.18 (historical control group) to 0.84 (successful-import group) scans per patient. CONCLUSION: Among ED transfer patients, CD import of outside imaging from the sending institution into the receiving institution's PACS significantly decreased the rates of subsequent imaging utilization.

Spiral head CT in the evaluation of acute intracranial pathology: a pictorial essay.

The purpose of this pictorial essay is to review the benefits of spiral head computed tomography (CT) with routine multiplanar reformations in the evaluation of acute intracranial pathology. This technique is particularly useful in trauma patients for detection of skull base or calvarial fractures, thin tentorial subdural hematomas, or for more specific characterization of intracranial hemorrhage. The benefits of multiplanar reformations have been described for a variety of other diagnoses in the chest, abdomen, extremities, and spine, and their routine use continues to grow with the widespread availability of multi-slice CT scanners. In this article, we describe spiral head CT technique with multiplanar reformations as an alternative to the routinely used sequential technique. Subtle findings and lesions aligned predominantly in the axial plane can often be visualized to better advantage with multiplanar reformations. We also address technical factors for optimizing spiral technique.

Comparison of respiratory motion artifact from craniocaudal versus caudocranial scanning with 64-MDCT pulmonary angiography.

OBJECTIVE: The purpose of this article is to compare respiratory motion artifact between craniocaudal versus caudocranial 64-MDCT acquisition for CT pulmonary angiography. MATERIALS AND METHODS: We retrospectively reviewed 100 consecutive emergency radiology CT pulmonary angiography examinations acquired on a 64-MDCT scanner between April 2007 and February 2008 for two groups of patients: caudocranial acquisition (mean age, 50.5 years; range, 16.6-84.2 years; mean [+/- SD] scan duration, 9.1 +/- 1.1 seconds) and craniocaudal acquisition (mean age, 56.5 years; range, 22.4-94.2 years; mean scan duration, 7.1 +/- 0.9 seconds). Two blinded readers reviewed randomized coronal reformatted images in lung windows and scored the severity of respiratory motion artifact in the upper, middle, and lower lung zones on a 4-point scale (0, no artifact; 1, mild; 2, moderate; and 3, severe). Caudocranial versus craniocaudal differences in artifact severity were assessed using the concordance statistic. The Student's t test was used to compare incidence of diagnostically limited examinations containing moderate or severe artifact. RESULTS: There were no statistically significant differences between scans obtained in the caudocranial versus craniocaudal scan direction in any lung zone or on the basis of the most severe artifact score per patient (p > 0.3). There were no significant differences between the groups with regard to the incidence of diagnostically limited scans (p > 0.25) containing either moderate or severe artifact. CONCLUSION: Craniocaudal CT pulmonary angiography multislice acquisition with a slight decrease in scan duration had a similar degree of respiratory motion artifact to caudocranial scanning, performing equivalently in all lung zones and on an overall patient-by-patient basis.

Nonoperative management of patients with a diagnosis of high-grade small bowel obstruction by computed tomography.

OBJECTIVE: To determine the natural history and treatment of high-grade small bowel obstruction (HGSBO). Small bowel obstruction is a frequent complication of abdominal surgery. Complete and strangulating obstructions are managed operatively while partial obstructions receive a trial of nonoperative therapy. The management and outcome of patients with HGSBO diagnosed by computed tomography (CT) has not been examined. DESIGN: Retrospective medical record review. Outcomes for nonoperative vs operative management were analyzed using Fisher exact and log-rank tests. SETTING: Tertiary care referral center. PATIENTS: One thousand five hundred sixty-eight consecutive patients admitted from the emergency department with a diagnosis of small bowel obstruction between 2000 and 2005 by CT criteria. MAIN OUTCOME MEASURES: Recurrence of symptoms and complications. RESULTS: One hundred forty-five patients (9%) with HGSBO were identified, with 88% follow-up (median, 332 days; range, 4-2067 days). Sixty-six (46%) were successfully managed nonoperatively while 79 (54%) required an operation. Length of stay and complications were significantly increased in the operative group (4.7 days vs 10.8 days and 3% vs 23%; P < .001). Nonoperative management was associated with a higher recurrence rate (24% vs 9%; P < .005) and shorter time to recurrence (39 days vs 105 days; P < .005) compared with operative intervention. Computed tomography signs of ischemia, admission laboratory results, and presence of cancer or inflammatory bowel disease were not predictive of an operation. CONCLUSIONS: Patients with HGSBO by CT can be managed safely with nonoperative therapy; however, they have a significantly higher rate of recurrence requiring readmission or operation within 5 years.

Outside CT imaging among emergency department transfer patients.

PURPOSE: The aim of this study was to characterize the quantity and types of outside computed tomographic (CT) examinations submitted for reinterpretation among emergency department (ED) transfers to a tertiary care, level I trauma, academic medical center and the frequency of and reasons for repeat imaging. METHODS: Reinterpretation requests for outside CT studies accompanying ED transfer patients over a 4-month period were prospectively audited. Clinicians completed forms specifying type of CT study, outside report availability, interpretational discrepancies, repeat imaging requests, and reasons for repeat imaging. RESULTS: A total of 425 CT studies were reviewed among 255 transfer patients, with a mean of 2.8 examinations (range, 0-16) on 1.7 patients (range, 0-8) per day. The patients' mean age was 59 years, and 57% were male. The clinicians reported no outside verbal or written reports for 16% of patients. Interpretational discrepancies were noted in 12% of those with outside reports. Repeat scans might have been avoided in as many as 25% of rescanned patients (35% of repeat examinations) because they were performed solely for imaging or information technology reasons (inadequate imaging, compact disc inoperability, or unavailable images within the hospital's picture archiving and communication system). Rescanned trauma patients in particular had a high per patient rate (32%) of potentially avoidable reasons, with a lower rate (11%) in nontrauma patients. CONCLUSION: Outside CT imaging in ED transfers adds workload and resource requirements for receiving institutions. A communication gap exists between transferring and receiving institutions, and interpretational discrepancies are common. Process improvement measures are suggested that might reduce the substantial rates of potentially avoidable reimaging.

Changes in thoracolumbar computed tomography and radiography utilization among trauma patients after deployment of multidetector computed tomography in the emergency department.

BACKGROUND: Diagnostic-quality thoracolumbar spine (TLS) images, generated from routine thoracoabdominal multidetector computed tomography (MDCT) data, have been demonstrated superior to conventional radiography (CR) for TLS injury. We evaluated thoracoabdominal computed tomography (CT) and TLS utilization among trauma patients after deployment of MDCT. We hypothesized that reformatted MDCT images replaced CR for evaluation of TLS trauma among patients undergoing chest or abdominal CT, and that utilization of thoracoabdominal CT and TLS screening in trauma increased postMDCT. METHODS: We reviewed all TLS imaging for trauma patients undergoing chest or abdominal CT for 18 months pre- and postMDCT. We compared the relative use of CR and CT in TLS imaging, and the volume of TLS screening, and chest and abdominal CT across the study period. We also reviewed TLS CR in patients not undergoing chest or abdominal CT. RESULTS: After MDCT deployment, CT replaced CR for TLS imaging among those undergoing chest or abdominal CT for trauma. Utilization of chest and abdominal CT and TLS screening significantly increased, despite unchanged volume and severity of trauma patients during the study period. There was a corresponding decrease in patients evaluated with thoracic spine CR alone CONCLUSIONS: Reformatted TLS images using thoracoabdominal CT data have replaced CR in our evaluation of TLS trauma. However, reasons for increased utilization remain unclear. Further studies are needed to determine whether clinical yield and cost-effectiveness warrant these changes in utilization.

Yield and utility of radiographic "shunt series" in the evaluation of ventriculo-peritoneal shunt malfunction in adult emergency patients.

We examined the yield and utility of shunt series (SS) performed for suspected shunt malfunction and whether an abnormal SS lead to shunt revision when head computed tomography (CT) was normal or unchanged. We reviewed medical records for all adult emergency patients over a 34-month period with suspected shunt malfunction imaged with both SS and head CT to determine whether a shunt revision was performed contemporaneous with imaging. Nine (3.4%) abnormal SS were identified among 263 studies performed. Among the 192 cases in which CT was normal or unchanged, two patients with abnormal SS underwent contemporaneous shunt revision. Yield of SS is very low, and in the presence of a normal or unchanged head CT, SS provides the imaging basis for contemporaneous shunt revision in 1% (2/192) of cases.

Recombinant human anti-transforming growth factor beta1 antibody therapy in systemic sclerosis: a multicenter, randomized, placebo-controlled phase I/II trial of CAT-192.

OBJECTIVE: To evaluate CAT-192, a recombinant human antibody that neutralizes transforming growth factor beta1 (TGFbeta1), in the treatment of early-stage diffuse cutaneous systemic sclerosis (dcSSc). METHODS: Patients with SSc duration of <18 months were randomly assigned to the placebo group or to 1 of 3 CAT-192 treatment groups: 10 mg/kg, 5 mg/kg, 0.5 mg/kg. Infusions were given on day 0 and weeks 6, 12, and 18. The primary objective of this study was to evaluate the safety, tolerability, and pharmacokinetics of CAT-192. Secondary outcomes included the modified Rodnan skin thickness score (MRSS), the Scleroderma Health Assessment Questionnaire, assessment of organ-based disease, serum levels of soluble interleukin-2 receptor, collagen propeptides (N propeptide of type I [PINP] and type III collagen), and tissue levels of messenger RNA for procollagens I and III and for TGFbeta1 and TGFbeta2. RESULTS: Forty-five patients were enrolled. There was significant morbidity and mortality, including 1 death in the group receiving 0.5 mg/kg of CAT-192 and 3 deaths in the group receiving 5 mg/kg of CAT-192. There were more adverse events and more serious adverse events in patients receiving CAT-192 than in those receiving placebo, although these events were not more frequent in the high-dose treatment group. The MRSS improved in all groups during the study, but there was no evidence of a treatment effect for CAT-192. Improvement in the MRSS correlated with the disease duration (r = -0.54, P = 0.0008). Changes in the PINP level from baseline correlated with changes in the MRSS (r = 0.37, P = 0.027). CONCLUSION: We report the first evaluation of a systemically administered and repeatedly dosed anti-TGFbeta1 drug. In this pilot study, CAT-192, in doses up to 10 mg/kg, showed no evidence of efficacy. The utility of clinical and biochemical outcome measures and the feasibility of multicenter trials of early dcSSc were confirmed.

Renal venous diversion: an unusual treatment for renal vein thrombosis.

Renal venous thrombosis most commonly occurs in the setting of nephrotic syndrome, hypercoagulability, or dehydration. This can usually be treated with systemic anticoagulation, and the diversion is via natural draining tributaries, eg, adrenal, lumbar, or gonadal veins. Occasionally, renal venous thrombosis results from extension of a thrombotic process, such as a large renal cell carcinoma with tumor thrombus extension into the infrahepatic inferior vena cava resulting in thrombosis of the inferior vena cava and contralateral renal vein. Herein, we report a case of left renal vein thrombosis relieved by diversion through the inferior mesenteric vein.

Lowering the thyroid dose in screening examinations of the cervical spine.

The first objective of this study was to test the hypothesis that a lower-dose (14.1 mGy thyroid dose) protocol for helical computed tomography (CT) of the entire cervical spine demonstrates equivalent technical adequacy and diagnostic accuracy as the standard-dose protocol (26.0 mGy thyroid dose) used at our institution. The second objective was to estimate the excess thyroid cancer mortality for three cervical spine screening protocols. Eight patients underwent two helical CT acquisitions of the entire cervical spine (standard and lower dose); from these acquisitions, a database of 128 randomized images (64 standard dose and 64 lower dose) was constructed. Three radiologists evaluated each of the 128 images for technical adequacy and, if the image was technically adequate, diagnostic accuracy. Historical data of excess thyroid cancer mortality stratified by age and sex were used to estimate the impact of lowering the thyroid dose in cervical spine screening. Estimates used a linear extrapolation of mortality data. The lower-dose protocol for helical CT of the entire cervical spine demonstrates equivalent technical adequacy and diagnostic accuracy as the standard protocol. The excess thyroid cancer mortality is a function of patient age and sex; for 25-year-old men, the excess mortality per 100,000 patients is 96.7 (standard-dose CT), 52.4 (lower-dose CT), and 6.7 (radiographs alone, 1.8 mGy thyroid dose). The equivalent technical adequacy and diagnostic accuracy of a lower-dose protocol for helical CT of the entire cervical spine support its implementation in routine screening. The excess thyroid mortality emphasizes the need to maintain an open dialogue with our referring clinicians with respect to the mechanism of injury, clinical findings, and radiation risks.

An ovary with a twist: a case of interesting sonographic findings of ovarian torsion.

An otherwise healthy young woman presented to the Emergency Department with abdominal pain. Multiple diagnoses were considered, as must be in cases of women with lower quadrant abdominal pain. Rapid identification of an abnormally enlarged ovary in close proximity to the opposite ovary on pelvic ultrasonography suggested the diagnosis of ovarian torsion. This was verified on laparoscopy. Of note is the fact that normal Doppler flow to both ovaries was demonstrated on pelvic ultrasound. We present this case, and its associated images, with the intent to highlight a readily identifiable sign of ovarian torsion for emergency physicians and to briefly review ovarian torsion's salient clinico-pathologic features.

Atlantoaxial instability associated with an orthotopic os odontoideum: a multimodality imaging assessment.

Radiography, computed tomography (CT), and magnetic resonance imaging exams of the cervical spine were performed in a 29-year-old man who was ultimately diagnosed with an orthotopic os odontoideum during admission for injuries sustained in a motor vehicle collision. Initial radiography suggested either os odontoideum or an acute fracture of the dens. Further imaging with CT and flexion and extension radiographs confirmed os odontoideum and excluded a dens fracture. Although rare, os odontoideum is an important cervical spine anomaly to consider and to distinguish from an acute fracture of the dens.

Quantification of clinical consultations in academic emergency radiology.

RATIONALE AND OBJECTIVES: The purpose of this study is to quantify the impact of clinical consultation on the workload of an academic emergency radiology section. MATERIALS AND METHODS: Data from a 7-day audit (24 h/d) of the number and length of clinical consultations was expressed as the mean number of consultations per 24 hours and consultation minutes per 24 hours. Consultations performed on images acquired from outside institutions were noted. The attending radiologist consultation fraction was defined as the attending consultation minutes per 24 hours divided by the number of minutes of attending coverage per 24 hours. Using annualized work relative value units per full-time employee (wRVU/FTE) over the 7 days, the consultation value unit per full-time employee (CVU/FTE) was defined and calculated as the consultation fraction multiplied by the annual wRVU/FTE. RESULTS: For the attending radiologists, the consultation fraction was 0.13 and the CVU/FTE was 1216. Twenty-two percent of the total consultation minutes were spent on studies performed outside our institution. CONCLUSIONS: Clinical consultation represents a significant portion of the workload in academic emergency radiology. The consultation fraction describes the fraction of the radiologist's time spent in consultation, and the CVU/FTE expresses the workload of clinical consultations in terms of wRVU/FTE, the factor used most commonly to determine the academic radiologist's productivity and staffing.