Diagnostic utility of whole-body computed tomography/pan-scan in trauma: a systematic review and meta-analysis study.

Trauma is a significant cause of mortality and morbidity. It is crucial to diagnose trauma patients quickly to provide effective treatment interventions in such conditions. Whole-body computed tomography (WBCT)/pan-scan is an imaging technique that enables a faster and more efficient diagnosis for polytrauma patients. The purpose of this systematic review and meta-analysis is to evaluate the efficacy of WBCT in diagnosing injuries in polytrauma patients. We will also assess its impact on the mortality rate and length of hospital stay among trauma centers between patients who underwent WBCT and those who did not (non-WBCT). Twenty-seven studies meeting our inclusion criteria were selected among PubMed, Scopus, Web of Science, and Google Scholar. The criteria were centered on the significance of WBCT/pan-scan application in trauma patients. Stata version 15 was used to perform statistical analysis on the data. The authors have also used I2 statistics to evaluate heterogeneity. Egger and Begg's tests were performed to rule out any publication bias. Total of twenty-seven studies including 68,838 trauma patients with a mean age of 45.0 ± 24.7 years were selected. Motor vehicle collisions were the most common cause of blunt injuries (80.0%). Head, neck, and face injuries were diagnosed in 44% (95% CI, 0.28-0.60; I2 = 99.8%), 6% (95% CI, 0.02-0.09; I2 = 97.2%), and 9% (95% CI, 0.05-0.13; I2 = 97.1%), respectively. Chest injuries were diagnosed by WBCT in 39% (95% CI, 0.28-0.51; I2 = 99.8%), abdominal injuries in 23% (95% CI, 0.03-0.43; I2 = 99.9%) of cases, spinal injuries 19% (95% CI, 0.11-0.27; I2 = 99.4%), extremity injuries 33% (95% CI, 0.23-0.43; I2 = 99.2%), and pelvic injuries 11% (95% CI, 0.04-0.18; I2 = 97.4%). A mortality odd ratio of 0.94 (95% CI, 0.83-1.06; I2 = 40.1%) was calculated while comparing WBCT and non-WBCT groups. This systematic review and meta-analysis provide insight into the possible safety, efficacy, and efficiency of WBCT/pan-scan as a diagnostic tool for trauma patients with serious injuries, regardless of their hemodynamic status. In patients with serious injuries from trauma, whether or not there are indicators of hemodynamic instability, our recommended approach is to, wherever possible, perform a WBCT without stopping the hemostatic resuscitation. By using this technology, the optimal surgical strategy for these patients can be decided upon without causing any delays in their final care or greatly raising their radiation dose.

Computed tomography pulmonary angiography (CTPA) for the detection of pulmonary embolism (PE) among trauma patients: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVES: Computed tomography pulmonary angiography (CTPA) is a standard imaging technique employed for the detection of pulmonary embolism (PE). This systematic review and meta-analysis aims to examine the prevalence of PE among the trauma patients undergoing CTPA. METHODS: A comprehensive search across PubMed, Scopus, Google Scholar, and Web of Science yielded 13 studies encompassing 5,570 individuals conducted following Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guideline. Studies that used CTPA for the detection of PE among the trauma patients were selected. This resulted in an evaluation of prevalence, trauma types, clinical manifestations, radiological findings, and mortality rates of PE among traumatic patients undergoing CTPA. RESULTS: The overall prevalence of PE among trauma patients undergoing CTPA was 18% (95% CI = 13-24%). After pooling the existing data, femur fractures were determined to be the most prevalent trauma type (12%). The most prevalent clinical manifestations of PE among trauma patients included shortness of breath, chest pain, and altered vital signs. Radiological findings encompassed various pulmonary abnormalities, such as opacity, ground-glass opacities, and pleural effusions. Mortality rates of PE among the trauma patients ranged from 0% to 29.4% across the included studies. CONCLUSION: This study provides comprehensive insights into the prevalence, clinical manifestations, radiological findings and mortality of PE among trauma patients undergoing CTPA. According to our findings, lower threshold for CTPA is recommended in patients with lower extremity or spine fractures.

Diagnostic utility of multidetector CT scan in penetrating diaphragmatic injuries: A systematic review and meta-analysis.

Penetrating diaphragmatic injuries pose diagnostic and management challenges. Computed tomography (CT) scans are valuable for stable patients, but concern exists for missed injuries and complications in nonoperatively managed cases. The objective of this study was to explore the diagnostic utility of multidetector CT scan (MDCT) in identifying diaphragmatic injuries resulting from penetrating trauma. A systematic review and meta-analysis were conducted, following established guidelines, by searching PubMed, Scopus, Web of Science, and Embase databases up to July 6, 2023. Eligible studies reporting MDCT's diagnostic accuracy in detecting penetrating diaphragmatic injuries were included. Relevant data elements were extracted and analyzed using STATA software. The study included 9 articles comprising 294 patients with confirmed penetrating diaphragmatic injuries through surgical procedures. MDCT's diagnostic performance revealed a pooled sensitivity of 74% (95% CI: 56%-87%) and a pooled specificity of 92% (95% CI: 79%-97%) (Fig. two), with significant heterogeneity in both sensitivity and specificity across the studies. The Fagan plot demonstrated that higher pre-test probabilities correlated with higher positive post-test probabilities for penetrating diaphragmatic injury diagnosis using MDCT, but even with negative results, there remained a small chance of having the injury, especially in cases with higher pre-test probabilities. This study highlights MDCT's effectiveness in detecting diaphragmatic injury from penetrating trauma, with moderate to high diagnostic accuracy. However, larger sample sizes, multicenter collaborations, and prospective designs are needed to address observed heterogeneity, enhancing understanding and consistency in MDCT's diagnostic capabilities in this context.

Radiology Perspective of Coronavirus Disease 2019 (COVID-19): Lessons From Severe Acute Respiratory Syndrome and Middle East Respiratory Syndrome.

OBJECTIVE. Since the outbreak of the novel coronavirus pulmonary illness coronavirus disease 2019 (COVID-19) in China, more than 79,000 people have contracted the virus worldwide. The virus is rapidly spreading with human-to-human transmission despite imposed precautions. Because similar pulmonary syndromes have been reported from other strains of the coronavirus family, our aim is to review the lessons from imaging studies obtained during severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) outbreaks. CONCLUSION. The review of experiences with the MERS and SARS outbreaks will help us better understand the role of the radiologist in combating the outbreak of COVID-19. The known imaging manifestations of the novel coronavirus and the possible unknowns will also be discussed.

The state of emergency radiology fellowships in North America and the development of a standardized curriculum.

BACKGROUND AND OBJECTIVES: The number of emergency radiology (ER) training programs in North America is small compared to the projected growth in demand for ER-trained radiologists. To date, there is no consensus-based training curriculum that sets a standard for all ER fellowship training programs. This study seeks to (1) identify the programmatic measures currently used in North American ER fellowship programs and (2) gather the perspectives of existing ER fellowship program directors (PD) and their recommendations for minimum and ideal curricular standards. METHODS: We distributed an 18-question survey to the PDs of every North American ER fellowship program (N = 15). Surveys were completed during the 2016-2017 academic year. We performed a cross-sectional analysis to gain an understanding of existing training curricula, expected areas of competency by the end-of-training, and PD opinions of what a standard ER training curriculum should contain. RESULTS: The data revealed heterogeneity in programmatic structure across the continent, as well as some areas of agreement. PD suggestions for a standard ER training curriculum showed consistency in many areas, including competency and proficiency expectations and clinical exposures, with some variability. These data were used to inform the creation of the first curricular standard for ER fellowship training. CONCLUSION: This study yielded the creation of a standard fellowship training resource for the field of ER. This deliverable serves as a curricular guideline for existing ER fellowships, as well as a model for new ER fellowship programs.

Highlights from the scientific and educational abstracts presented at the ASER 2015 annual scientific meeting and postgraduate course.

The American Society of Emergency Radiology (ASER) 2015 Annual Scientific Meeting and Postgraduate Course offered dedicated learning sessions, oral presentations, and digital exhibits on a broad spectrum of topics in emergency radiology, including traumatic and non-traumatic emergencies, quality, communication, education, technological innovations, and the evolving identity of the emergency radiology subspecialty. This article highlights the scientific and educational abstracts presented at the meeting.

Highlights from the scientific and educational abstracts presented at the ASER 2014 Annual Scientific Meeting and Postgraduate Course.

The American Society of Emergency Radiology (ASER) 2014 Annual Scientific Meeting and Postgraduate Course offered dedicated learning sessions, oral presentations, and digital exhibits on a broad spectrum of topics in emergency radiology, including traumatic and nontraumatic emergencies, quality, communication, education, and technology. This article highlights the scientific and educational abstracts presented at the meeting (Emerg Radiol 21:431-471, 2014).

Highlights from the scientific and educational abstracts presented at the ASER 2013 Annual Scientific Meeting and Postgraduate Course.

The American Society of Emergency Radiology (ASER) 2013 Annual Scientific Meeting and Postgraduate Course offered dedicated learning sessions, oral presentations, and digital exhibits on a broad spectrum of topics in emergency radiology, including traumatic and nontraumatic emergencies, quality, communication, education, and technology. This article highlights the scientific and educational abstracts presented at the meeting.

Diagnostic accuracy of computed tomography findings for hollow viscus injuries following thoracoabdominal gunshot wounds.

BACKGROUND: Selective nonoperative management (SNOM) of abdominal gunshot wounds (GSWs) is increasingly used as computed tomography (CT) has become a diagnostic adjunct for the evaluation of intraabdominal injuries including hollow viscus injuries (HVIs). Currently, there is scarce data on the diagnostic accuracy of CT for identifying HVI. The purpose of this study was to determine the diagnostic accuracy of different CT findings in the diagnosis of HVI following abdominal GSW. METHODS: This retrospective single-center cohort study was performed from January 2015 to April 2019. We included consecutive patients (≥18 years) with abdominal GSW for whom SNOM was attempted and an abdominal CT was obtained as a part of SNOM. Computed tomography findings including abdominal free fluid, diffuse abdominal free air, focal gastrointestinal wall thickness, wall irregularity, abnormal wall enhancement, fat stranding, and mural defect were used as our index tests. Outcomes were determined by the presence of HVI during laparotomy and test performance characteristics were analyzed. RESULTS: Among the 212 patients included for final analysis (median age: 28 years), 43 patients (20.3%) underwent a laparotomy with HVI confirmed intraoperatively whereas 169 patients (79.7%) were characterized as not having HVI. The sensitivity of abdominal free fluid was 100% (95% confidence interval [CI]: 92-100). The finding of a mural defect had a high specificity (99%, 95% CI: 97-100). Other findings with high specificity were abnormal wall enhancement (97%, 95% CI: 93-99) and wall irregularity (96%, 95% CI: 92-99). CONCLUSION: While there was no singular CT finding that confirmed the diagnosis of HVI following abdominal GSW, the absence of intraabdominal free fluid could be used to rule out HVI. In addition, the presence of a mural defect, abnormal wall enhancement, or wall irregularity is considered as a strong predictor of HVI. LEVEL OF EVIDENCE: Diagnostic Test or Criteria; Level II.

The trauma pelvic X-ray: Not all pelvic fractures are created equally.

BACKGROUND: The primary aim of this study was to evaluate the role of the initial pelvic X-ray in identifying significant pelvic fractures, which could result in changes in the management of the patient. METHODS: Patients admitted to a level I trauma center (2010-2019) with a severe blunt pelvic fracture (AIS ≥3) were identified. Included in the analysis were patients who underwent emergency department pelvic X-ray followed by CT scan. A control group of patients without pelvic fractures was also included in the study. All investigations were reviewed by a blinded attending trauma radiologist. Pelvic X-ray findings and CT scan reports were compared according to the specific pelvic fracture location, and severity. RESULTS: Overall, pelvic X-ray was diagnosed 252 of the 285 pelvic fractures (sensitivity 88.4%) and wrongly diagnosed a facture in 3 of 97 patients without a fracture (specificity 96.9%). In 29/184 (15.8%) of patients with pelvic fracture AIS 3, the pelvic X-ray was read as normal, missing the fracture, compared with 4/101 (4.0%) in the AIS 4/5 group (p = 0.003). Pelvic X-ray had the lowest sensitivity in ischial (10.7%), iliac (28.7%), acetabular (42.4%), and sacral fractures (49.1%) and was best for detecting symphysis diastasis (89.8%). CONCLUSION: Pelvic X-ray is useful in identifying pubic symphysis diastasis. However, it misses or underestimates a significant number of fractures. CT scan evaluation should be performed in patients with a suspicious mechanism or clinical suspicion of pelvic fracture.

ACR Appropriateness Criteria® Lower Extremity Arterial Claudication-Imaging Assessment for Revascularization: 2022 Update.

Arterial claudication is a common manifestation of peripheral artery disease. This document focuses on necessary imaging before revascularization for claudication. Appropriate use of ultrasound, invasive arteriography, MR angiography, and CT angiography are discussed. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

SARS-CoV-2 reinfection: "New baseline" imaging concept in the era of COVID-19.

Recent reports have suggested COVID-19 relapse or reinfection may lead to readmission, which may cause a diagnostic challenge between recently infected patients and reinfections. Compounding this problem is the post-viral lung sequela that may be expected after COVID-19 pneumonia, similar to both SARS and MERS. Although chest imaging may play a role in the diagnosis of primary SARS-CoV-2 infection, reinfection or relapse of COVID-19 will have similar imaging findings. A "new-baseline" imaging can be obtained from COVID-19 patients at the time of hospital discharge or clinical recovery. This new reference can not only determine if readmissions are from relapse or reinfection of COVID-19, resolving COVID-19 or potentially a different viral infection (influenza), but also for long term sequela of COVID-19 lung infection. Strategic use of imaging before discharge may be helpful in the subset of the population at the highest risk of a secondary viral infection such as influenza. Determining the residual abnormalities in post-discharge imaging can guide us in the long-term management of patients for many years to come.

Reason for Exam Imaging Reporting and Data System: Consensus Reached on Quality Assessment of Radiology Requisitions.

OBJECTIVE: The aim of this study was to reach consensus on quality assessment of clinical information in imaging requisitions using Reason for exam Imaging Reporting and Data System (RI-RADS). METHODS: A Delphi study was conducted in September 2018 with a panel of 87 radiologists with diverse levels of experience from various settings (community hospitals, private hospitals, university hospitals, and clinics), of which 74.7% completed the survey. The agreement was assessed in the following subjects: (a) presumed effect of standardization, (b) the standardized system for information, (c) the scoring system for evaluation of requisitions, and (d) the implementation of RI-RADS. The consensus threshold was set at 51% responding (strongly) agree. The rate of lawsuits preventable with clinical information was also assessed. RESULTS: Consensus was reached on all objectives of the study with a high level of agreement. Radiologists agreed on the need for standardization of imaging requisitions and attributed it to increased speed and accuracy of interpretations. Three categories of information were determined as key indicators of quality: impression, clinical findings, and clinical question. The scoring system is intended to grade requisitions based on the presence of these categories. Radiologists also agreed that RI-RADS will encourage physicians to improve requisitions. Among radiologists who responded to the survey, 12.6% had experienced at least one lawsuit potentially preventable with sufficient information in requisitions. CONCLUSIONS: Reason for exam Imaging Reporting and Data System can be used as a standard for quality assessment of requisitions. Its use may improve the quality of patient care and reduce lawsuits against radiologists.

Coronavirus (COVID-19) Outbreak: What the Department of Radiology Should Know.

In December 2019, a novel coronavirus (COVID-19) pneumonia emerged in Wuhan, China. Since then, this highly contagious COVID-19 has been spreading worldwide, with a rapid rise in the number of deaths. Novel COVID-19-infected pneumonia (NCIP) is characterized by fever, fatigue, dry cough, and dyspnea. A variety of chest imaging features have been reported, similar to those found in other types of coronavirus syndromes. The purpose of the present review is to briefly discuss the known epidemiology and the imaging findings of coronavirus syndromes, with a focus on the reported imaging findings of NCIP. Moreover, the authors review precautions and safety measures for radiology department personnel to manage patients with known or suspected NCIP. Implementation of a robust plan in the radiology department is required to prevent further transmission of the virus to patients and department staff members.

Coronavirus Outbreak: Is Radiology Ready? Mass Casualty Incident Planning.

On March 11, 2020, the World Health Organization declared a coronavirus disease 2019 (COVID-19) pandemic. Health care systems worldwide should be prepared for an unusually high volume of patients in the next few weeks to months. Even the most efficient radiology department will undergo tremendous stress when victims of a mass casualty flood the emergency department and in turn the radiology department. A significant increase is expected in the number of imaging studies ordered for the initial diagnosis and treatment follow-up of cases of COVID-19. Here, we highlight recommendations for developing and implementing a mass casualty incident (MCI) plan for a viral outbreak, such as the current COVID-19 infection. The MCI plan consists of several steps, including preparation, mobilization of resources, imaging chain, adjusting imaging protocols, and education, such as MCI plan simulation and in-service training. Having an MCI plan in place for a viral outbreak will protect patients and staff and ultimately decrease virus transmission. The use of simulations will help identify throughput and logistical issues.

Coronavirus disease 2019 (COVID-19) pandemic: Review of guidelines for resuming non-urgent imaging and procedures in radiology during Phase II.

Since the spread of the coronavirus disease 2019 (COVID-19) was designated as a pandemic by the World Health Organization, health care systems have been forced to adapt rapidly to defer less urgent care during the crisis. The United States (U.S.) has adopted a four-phase approach to decreasing and then resuming non-essential work. Through strong restrictive measures, Phase I slowed the spread of disease, allowing states to safely diagnose, isolate, and treat patients with COVID-19. In support of social distancing measures, non-urgent studies were postponed, and this created a backlog. Now, as states transition to Phase II, restrictions on non-essential activities will ease, and radiology departments must re-establish care while continuing to mitigate the risk of COVID-19 transmission all while accommodating this backlog. In this article, we propose a roadmap that incorporates the current practice guidelines and subject matter consensus statements for the phased reopening of non-urgent and elective radiology services. This roadmap will focus on operationalizing these recommendations for patient care and workforce management. Tiered systems are proposed for the prioritization of elective procedures, with physician-to-physician communication encouraged. Infection control methods, provision of personal protective equipment (PPE), and physical distancing measures are highlighted. Finally, changes in hours of operation, hiring strategies, and remote reading services are discussed for their potential to ease the transition to normal operations.

Radiologic predictors of in-hospital mortality after traumatic craniocervical dissociation.

BACKGROUND: Traumatic craniocervical dissociation (CCD) is the forcible dislocation of the skull from the vertebral column. Because most CCD patients die on scene, prognostication for those who arrive alive to hospital is challenging. The study objective was to determine if greater dissociation, based on radiologic measurements of CCD, is predictive of in-hospital mortality among patients surviving to the emergency department. METHODS: All trauma patients arriving to our Level 1 trauma center (January 2008 to April 2019) with CCD were retrospectively identified and included. Transfers and patients without computed tomography head/cervical spine were excluded. Study patients were dichotomized into groups based on in-hospital mortality. Radiologic measurements of degree of CCD were performed based on the index computed tomography scan by an attending radiologist with Emergency Radiology fellowship training. Measurements were compared between patients who died in-hospital versus those who survived. RESULTS: After exclusions, 36 patients remained: 12 (33%) died and 24 (67%) survived. Median age was 55 years (30-67 years) versus 44 (20-61 years) (p = 0.199). Patients who died had higher Injury Severity Score (39 [31-71] vs. 27 [14-34], p = 0.019) and Abbreviated Injury Scale head/neck score (5 [5-5] vs. 4 [3-4], p = 0.001) than survivors. The only radiologic measurement that differed between groups was greater soft tissue edema at mid C1 among patients who died (12.37 [7.60-14.95] vs. 7.86 [5.25-11.61], p = 0.013). Receiver operating characteristic curve analysis of soft tissue edema at mid C1 and mortality revealed 10.86 mm or greater of soft tissue width predicted mortality with sensitivity and specificity of 0.75. All other radiologic parameters, including the basion-dens interval, were comparable between groups (p > 0.05). CONCLUSION: Among patients who arrive alive to hospital after traumatic CCD, greater radiologic dissociation is not associated with increased mortality. However, increased soft tissue edema at the level of mid C1, particularly 10.86 mm or greater, is associated with in-hospital death. These findings improve our understanding of this highly lethal injury and impart the ability to better prognosticate for patients arriving alive to hospital with CCD. LEVEL OF EVIDENCE: Prognostic and Epidemiological, Level III.

Seroepidemiologic and occupational risk survey for Coxiella burnetii antibodies among US veterinarians.

BACKGROUND: Little is known about the occurrence of Q fever among veterinarians in the United States. In this study, we sought to estimate the prevalence of Coxiella burnetii antibodies among veterinarians and to identify risk factors for exposure. METHODS: We tested serum samples from 508 veterinarians who attended the 143rd American Veterinary Medical Association Annual Convention in 2006. Samples were screened using a Q fever IgG enzyme-linked immunosorbent assay (ELISA). Samples with positive or equivocal results of ELISA were confirmed using phase I and phase II IgG immunofluorescence antibody assays, and end point IgG titers were determined for samples with positive results. RESULTS: Antibodies against C. burnetii were detected in 113 (22.2%) of 508 veterinarians. Risk factors associated with seropositivity included age 46 years, routine contact with ponds, and treatment of cattle, swine, or wildlife. CONCLUSIONS: Veterinarians have a high level of exposure to C. burnetii, the causative organism of Q fever, especially those veterinarians who treat livestock. In this study, risk of C. burnetii seropositivity was also independently associated with contact with ponds. The role of exposure to standing bodies of water in infection is not usually considered and should be investigated in future studies. Additionally, the evidence of past infection with C. burnetii in >20% of veterinarians also highlights the need for use of appropriate personal protective equipment when treating animals that are potentially infected with C. burnetii. Physicians should consider the risk of infection with C. burnetii when treating ill veterinarians and others with potential occupational exposures.

Prevalence of and risk factors for serum antibodies against Leptospira serovars in US veterinarians.

OBJECTIVE: To determine the seroprevalence of antibodies against Leptospira serovars among veterinarians and identify risk factors for seropositivity in veterinary care settings. DESIGN: Seroepidemiologic survey. STUDY POPULATION: Veterinarians attending the 2006 AVMA Annual Convention. PROCEDURES: Blood samples were collected from 511 veterinarians, and serum was harvested for a microcapsule agglutination test (MAT) to detect antibodies against 6 serovars of Leptospira. Aggregate data analysis was performed to determine the ratio of the odds of a given exposure (eg, types of animals treated or biosafety practices) in seropositive individuals to the odds in seronegative individuals. RESULTS: Evidence of previous leptospiral infection was detected in 2.5% of veterinarians. Most veterinarians reported multiple potential exposures to Leptospira spp and other pathogens in the previous 12 months, including unintentional needlestick injuries (379/511 [74.2%]), animal bites (345/511 [67.5%]), and animal scratches (451/511 [88.3%]). Treatment of a dog with an influenza-like illness within the past year was associated with seropositivity for antibodies against Leptospira spp. CONCLUSIONS AND CLINICAL RELEVANCE: Veterinarians are at risk for leptospirosis and should take measures to decrease potential exposure to infectious agents in general. Diagnostic tests for leptospirosis should be considered when veterinarians have febrile illnesses of unknown origin.

Comparison of FDG-PET/CT and CT for delineation of lumpectomy cavity for partial breast irradiation.

PURPOSE: The success of partial breast irradiation critically depends on proper target localization. We examined the use of fluorodeoxyglucose-positron emission tomography (FDG-PET)/computed tomography (CT) for improved lumpectomy cavity (LC) delineation and treatment planning. METHODS AND MATERIALS: Twelve breast cancer patients underwent FDG-PET/CT on a GE Discovery scanner with a median time from surgery to PET/CT of 49 days. The LC was contoured on the CT scan by a radiation oncologist and, together with a nuclear medicine physician, on the PET/CT scan. The volumes were calculated and compared in each patient. Treatment planning target volumes (PTVs) were calculated by expanding the margin 2 cm beyond the LC, maintaining a 5-mm margin from the skin and chest wall, and the treatment plans were evaluated. In addition, a study with a patient-like phantom was conducted to evaluate the effect that the window/level settings might have on contouring. RESULTS: The margin of the LC was well visualized on all FDG-PET images. The phantom results indicated that the difference between the known volume and the FDG-PET-delineated volume was <10%, regardless of the window/level settings. The PET/CT volumes were larger than the CT volumes in all cases (median volume ratio, 1.68; range, 1.24-2.45; p = 0.004). The PET/CT-based PTVs were also larger than the CT-based PTV (median volume ratio, 1.16; range, 1.08-1.64; p = 0.006). In 9 of 12 patients, a CT-based treatment plan did not provide adequate coverage of the PET/CT-based PTV (99% of the PTV received <95% of the prescribed dose), resulting in substantial cold spots in some plans. In these cases, treatment plans were generated which were specifically designed to cover the larger PET/CT-based PTV. Although these plans showed an increased dose to the normal tissues, the increases were modest: the non-target breast volume receiving > or =50 Gy, lung volume receiving > or =30 Gy, and heart volume receiving > or =5 Gy increased by 5.7%, 0.8%, and 0.2%, respectively. The normal tissue dose-volume objectives were still met with these plans. CONCLUSION: The results of our study have shown that FDG-PET/CT can be used to define the LC volume. The increased FDG uptake was likely a result of postoperative inflammation in the LC. The targets defined using PET/CT were significantly larger than those defined with CT alone. Our results have shown that treatment plans can be generated to cover these larger PET/CT target volumes with only a modest increase in irradiated tissue volume compared with CT-determined PTVs.