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Plexopathy may be caused by diverse pathologies, including trauma, nerve entrapment, neoplasm, inflammation, infection, autoimmune disease, hereditary disease, and idiopathic etiologies. For patients presenting with brachial or lumbosacral plexopathy, dedicated plexus MRI is the most appropriate initial imaging modality for all clinical scenarios and can identify processes both intrinsic and extrinsic to the nerves. Other imaging tests may be appropriate for initial imaging depending on the clinical scenario. This document addresses initial imaging strategies for brachial and lumbosacral plexopathy in the following clinical situations: nontraumatic plexopathy with no known malignancy, traumatic plexopathy (not perinatal), and plexopathy occurring in the context of a known malignancy or posttreatment syndrome. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Spine infection is both a clinical and diagnostic imaging challenge due to its relatively indolent and nonspecific clinical presentation. The diagnosis of spine infection is based upon a combination of clinical suspicion, imaging evaluation and, when possible, microbiologic confirmation performed from blood cultures or image-guided percutaneous or open spine biopsy. With respect to the imaging evaluation of suspected spine infection, MRI without and with contrast of the affected spine segment is the initial diagnostic test of choice. As noncontrast MRI of the spine is often used in the evaluation of back or neck pain not responding to conservative medical management, it may show findings that are suggestive of infection, hence this procedure may also be considered in the evaluation of suspected spine infection. Nuclear medicine studies, including skeletal scintigraphy, gallium scan, and FDG-PET/CT, may be helpful in equivocal or select cases. Similarly, radiography and CT may be appropriate for assessing overall spinal stability, spine alignment, osseous integrity and, when present, the status of spine instrumentation or spine implants. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

In the United States, acute low back pain, with or without radiculopathy, is the leading cause of years lived with disability and the third ranking cause of disability-adjusted life-years. Uncomplicated acute low back pain and/or radiculopathy is a benign, self-limited condition that does not warrant any imaging studies. Imaging is considered in those patients who have had up to 6 weeks of medical management and physical therapy that resulted in little or no improvement in their back pain. It is also considered for those patients presenting with red flags, raising suspicion for a serious underlying condition, such as cauda equina syndrome, malignancy, fracture, or infection. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

COVID-19 was initially described as a pulmonary disease. Increasing attention is now directed to extrapulmonary disease manifestations mediated by viral tropism to the vascular endothelium. Here, we report a case of an adult patient with COVID-19 who presented to the emergency department with neurological signs disproportionate to pulmonary symptoms and was found to have a subacute ischemic stroke. Imaging studies suggested an active inflammatory vasculopathy. The case highlights the utility of vascular wall imaging studies when positive findings are present on emergent CT angiography. Current treatment algorithms should consider the addition of adjunct intracranial vessel wall imaging to assess for inflammatory vasculopathy when a patient with acute or recent COVID infection presents to the emergency department with stroke.

Myelopathy is a clinical diagnosis with localization of the neurological findings to the spinal cord, rather than the brain or the peripheral nervous system, and then to a particular segment of the spinal cord. Myelopathy can be the result of primary intrinsic disorders of the spinal cord or from secondary conditions, which result in extrinsic compression of the spinal cord. While the causes of myelopathy may be multiple, the acuity of presentation and symptom onset frame a practical approach to the differential diagnosis. Imaging plays a crucial role in the evaluation of myelopathy with MRI the preferred modality. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

The gold standard for imaging of meningiomas is MRI with gadolinium-based contrast agent. Due to increased costs, time, and uncertain chronic effects of gadolinium exposure, use of noncontrast T2-weighted imaging (T2WI) in lieu of contrast-enhanced MRI has been an increasing focus of research across various diagnostic scenarios. The purpose of this study was to evaluate the diagnostic accuracy of T2WI in detecting changes in meningioma tumor volume.Imaging and clinical data were reviewed for 82 consecutive patients undergoing MR-surveillance of intracranial meningioma. Using volumetric-T2WI, two neuroradiologists independently calculated tumor volumes. Measurements were compared to a baseline study contrast-enhanced T1 tumor volume. Using contrast-enhanced sequences as the reference standard, statistical analysis was performed to determine the accuracy of T2WI in detecting changes of meningioma volume.Using only T2WI, readers detected meningioma volume change ≥ 20% in 19/82 patients and volume change20% in 63/82 patients. Reader accuracy for detecting change in tumor volume on T2WI ≥ 20% was 0.85, sensitivity 0.65, specificity 0.93, positive predictive value (PPV) 0.79, and negative predictive value (NPV) 0.87. For meningiomas1 ml, reader accuracy for detecting change in tumor volume on T2WI ≥20% was 0.90, sensitivity 0.78, specificity 0.95, PPV 0.88, and NPV 0.91. Change in tumor volume on T2WI ≥20% was detected with 100% accuracy for posterior fossa meningiomas. Inter-reader agreement for all meningiomas was moderate (κ = 0.45) improving to substantial agreement (κ = 0.77) with tumor volumes1 ml.Volumetric-T2WI detects changes in meningioma volume with comparable accuracy to gold standard T1 postcontrast imaging, particularly with higher tumor volumes and posterior fossa locations.

BACKGROUND AND PURPOSE The diagnostic utility of contrast MR-imaging in adult new-onset seizures without clinically suspected neoplasia or infection is not well defined in the literature. Imaging guidelines consider both contrast and noncontrast MR-imaging examinations appropriate in this clinical scenario. The purpose of this study was to evaluate the utility of contrast MR-sequences in evaluation of seizure in patients without suspicion for neoplasia or infection. METHODS Imaging and clinical data were reviewed for 103 consecutive patients admitted for phase-1 seizure monitoring with the following criteria: (1) MRI-brain performed with/without intravenous contrast; (2) no clinical suspicion for central nervous system (CNS) infection; and (3) no history of CNS neoplasia, or suspected metastatic disease. Readers designated cases as lesional or nonlesional. Lesional cases were further categorized as either visualized on noncontrast sequences only, contrast sequences only, or both. RESULTS 29/103 (28%) patients had epileptogenic lesions, 74/103 (72%) were nonlesional studies. 29/29 (100%) lesional abnormalities were detected on noncontrast sequences (sensitivity 100% [95 confidence interval (CI): 88-100], specificity 100% [95 CI: 95-100]). 23/29 (79.3%) lesional cases were visualized on both noncontrast and postcontrast sequences. 6/29 (20.7%) were visualized only on noncontrast sequences. No lesional cases were detected exclusively on postcontrast MR sequences. With an observed nonlesional extraneous contrast MR-imaging rate of 72%, estimated excess cost of contrast MR-imaging per 1000 patients using Medicare data was $103,680 USD. CONCLUSIONS Contrast MR-imaging has limited diagnostic utility in initial screening of adult new-onset seizure patients without clinically suspected neoplasia or infection. More judicious use of contrast MR-imaging in this patient population may reduce unnecessary exposure to gadolinium and lower associated healthcare costs.

Introduction: Multiple societal guidelines recommend patients with TIA be emergently imaged with brain-MRI and neurovascular screening-CTA, MRA or carotid ultrasound-to identify and treat risk factors for future stroke. Increased ED compliance with TIA imaging guidelines has previously been demonstrated, along with a substantial increase in imaging utilization over the past decade. The purpose of this study was to quantify prevalence of redundant imaging during ED work-up of TIA, and to identify imaging practices that could be targeted to reduce unnecessary expenditures. Methods: Utilizing the 2006-2017 Nationwide Emergency Department Sample, patients discharged with TIA from EDs in the US were identified using ICD-9/10 codes. Brain and neurovascular imaging obtained during the encounter was identified using CPT codes. Demographics, payor, patient income, and hospital characteristics were incorporated into a hierarchical multivariable logistic regression analysis to identify significant associations with redundant neuroimaging. Results: In 2017 there were 184,870 patients discharged from EDs with TIA. Redundant brain, brain vascular, and cervical vascular imaging was identified in 55,513(30%), 5,149(2.8%) and 1,325(0.7%) of encounters respectively. Decreased odds of obtaining redundant neuroimaging in a TIA encounter was observed in Medicaid patients(OR:0.72, 95%CI:0.64-0.81), non-trauma centers(OR:0.49, 95%CI:0.26-0.93), rural hospital locations(OR:0.18, 95%CI:0.11-0.29) and weekend encounters(OR:0.9, 95%CI:0.85-0.96). Trend analysis from 2006 to 2017 demonstrated a rise in redundant brain and neurovascular imaging from 2.3% and 0.2% of encounters respectively in 2006 to 30% and 3.5% of encounters in 2017. Using Medicare fee estimates, in 2017 redundant brain and neurovascular imaging for patients discharged from EDs with TIA resulted in additional charges of approximately 8,670,832 USD. Conclusion: Increasing utilization of imaging for workup of TIA across EDs in the US is also associated with substantial and increasing use of redundant imaging. We identify redundant brain and neurovascular imaging as areas that could be targeted to mitigate rising imaging expenditures.

Background and Purpose: Multiple societal guidelines recommend urgent brain and neurovascular imaging in patients with transient ischemic attack (TIA) to identify and treat risk factors that may lead to future stroke. The purpose of this study was to evaluate whether national imaging utilization for workup of TIA complies with society guidelines. Methods: Analysis utilized the Nationwide Emergency Department Sample. Primary analysis was performed on a 2017 cohort, and secondary trend analysis was performed on cohorts from 2006 to2017. Patients diagnosed and discharged from emergency departments with TIA were identified using International Classification of Diseases, Ninth Revision and Tenth Revision codes. Brain and neurovascular imaging obtained during the encounter was identified using Current Procedural Terminology codes. Demographics, health insurance, patient income, and hospital-type covariates were analyzed using a hierarchical multivariable logistic regression analysis to identify predictors of obtaining neurovascular imaging during an emergency department encounter. Results: In 2017, there were 167 999 patients evaluated and discharged from emergency departments with TIA. The percentage of patients receiving brain and neurovascular imaging was 78.5% and 43.2%, respectively. The most common imaging workup utilized was a solitary computed tomography–brain without any neurovascular imaging (30.9% of encounters). Decreased odds of obtaining neurovascular imaging was observed in Medicaid patients (odds ratio, 0.65 [95% CI, 0.58–0.74]), rural hospitals (odds ratio, 0.26 [95% CI, 0.17–0.41]), nontrauma centers (odds ratio, 0.40 [95% CI, 0.21–0.74]), and weekend encounters (odds ratio, 0.91 [95% CI, 0.85–0.96]). Trend analysis demonstrated a steady rise in brain and neurovascular imaging in 2006 from 34.9% and 6.8% of encounters, respectively, to 78.5% and 43.2% of encounters in 2017. Conclusions: Compliance with imaging guidelines is improving; however, the majority of TIA patients discharged from the emergency department do not receive recommended neurovascular imaging during their encounter. Follow-up studies are needed to determine whether delayed or incomplete vascular screening increases the risk of future stroke.

We present a case of a 57-year-old female with four-months of diplopia and vertigo. MRI revealed a mixed cystic and solid partially enhancing lesion of the 4th ventricle, foramen of Luschka and cerebellopontine angle. Preoperative differential diagnosis favored ependymoma. Biopsy revealed a neurenteric cyst, a benign developmental lesion that rarely occurs intracranially. This case highlights several atypical manifestations of intracranial neurenteric cyst, with regions of histologically benign solid enhancement, multicompartmental extra-axial location mimicking an ependymoma, and rapid recurrence without evidence of underlying malignancy.

Introduction: Multiple societal guidelines recommend urgent imaging in patients with transient ischemic attack (TIA) to identify and treat risk factors that may lead to future stroke. Recommended studies include brain imaging, preferably with MRI, and neurovascular imaging (cranio-cervical CTA, cranio-cervical MRA or carotid ultrasound). The purpose of this study was to evaluate whether emergency department (ED) imaging utilization practices comply with recommended guidelines. Methods: Analysis utilized the Nationwide Emergency Department Sample (NEDS), a comprehensive, nationally representative sample of ED visits. Primary analysis was performed on the 2016 cohort, and a secondary trend analysis was performed on cohorts from 2006-2016. Patients diagnosed and discharged from the emergency department with transient ischemic attack were identified using ICD-9 and ICD-10 codes. Brain and neurovascular imaging obtained during the encounter were identified using CPT codes. Demographics, health insurance, patient income, and hospital type data were analyzed and a survey weighted logistic regression analysis was performed to identify predictors of obtaining neurovascular imaging. Results: In 2016 there were 183,216 patients evaluated and discharged from emergency departments with TIA. The percentage of patients receiving brain and neurovascular imaging was 75.73% and 37.99% respectively. Of the top 5 imaging work-ups utilized, the most common (34.06% of cases) was a solitary noncontrast head CT without any neurovascular imaging. Decreased odds of obtaining neurovascular imaging was observed in Medicaid patients (OR: 0.73, 95%CI: 0.66-0.80), non-trauma centers (OR: 0.42, 95%CI: 0.38-0.45), and rural hospital locations (OR: 0.30, 95%CI: 0.27-0.33). Trend analysis demonstrated a steady rise in brain and neurovascular imaging from 34.02% and 6.51% of encounters respectively in 2006 to 75.73% and 37.99% of encounters in 2016. Conclusion: The majority of TIA patients discharged from the ED do not receive recommended neurovascular imaging during their encounter. Follow-up studies are needed to determine whether delayed or incomplete vascular screening increases the risk of future stroke.

The utilization of spinal interventional pain techniques has grown rapidly over the last decade. However, practitioners use widely different techniques in these procedures, particularly in the use of image guidance. The importance of image guidance was highlighted by the fact that in recent systematic reviews on therapeutic effectiveness of epidural steroid injections and facet joint interventions, only studies that used image guidance were included. The choice of image guidance remains a matter of physician preference with conventional fluoroscopic or Computed Tomography (CT) guidance most common. There are many advantages to CT guidance for certain spinal interventional pain procedures, mainly due to increased needle tip positioning accuracy. CT guidance provides greater anatomical detail that facilitates accurate needle trajectory planning, monitoring and final placement. Unlike conventional fluoroscopy that may be hindered by tissue overlap and lack of surrounding anatomical detail CT guidance offers direct visualization of the entire needle trajectory and the surrounding soft tissue and bone structures. Large osteophytes and adjacent vascular structures can be identified and safely avoided. The goals of this narrative review are to provide a basic overview of CT techniques available for spinal interventional pain procedures, to discuss the potential advantages and disadvantages of CT guidance, to provide a simple step-by-step approach to use of CT guidance, to share technical pearls, and to discuss methods to avoid potential pitfalls. This review will provide interventional pain physicians with knowledge of relevant CT image acquisition techniques and appropriate radiation dose reduction strategies. This will contribute to increased technical success rates while reducing radiation dose to the patient and staff. Key words: Computed tomography, fluoroscopy, analgesia, epidural injection, spinal injection, back pain, safety

BACKGROUND AND PURPOSE: Cauda equina syndrome typically requires emergent MR imaging to detect compressive lesions on the cauda equina, which may require surgical decompression. While CT is sometimes performed as a complementary imaging technique to evaluate osseous integrity in patients with cauda equina syndrome, the accuracy of CT in detecting significant spinal stenosis and cauda equina impingement is not well-defined in the literature. We hypothesized that percentage thecal sac effacement on CT of the lumbar spine would have high sensitivity and high negative predictive value in evaluating significant spinal stenosis and cauda equina impingement. MATERIALS AND METHODS: We analyzed imaging studies for 151 consecutive patients with clinically suspected cauda equina syndrome. The percentage thecal sac effacement (

Functional neurosurgery is a rapidly growing field with exciting future potential applications. This article describes currently used implanted electronic devices for neurologic stimulation and monitoring. The devices to be reviewed include invasive EEG electrodes, deep brain stimulator, motor cortex stimulator, responsive neurostimulation, osteo-integrated hearing aid, middle ear implant, cochlear implant, auditory brainstem implant, vagal nerve stimulator and spinal cord stimulator. Emphasis is placed on the normal components, function, positioning, potential complications and MRI safety of these devices. Understanding the motivations and appropriate use of these implantable devices is critical for clinical neuroradiologists to provide relevant imaging interpretation and protocols for patients and referring physicians.

The gastrointestinal tract is secured in place by various suspensory ligaments. Laxity or incomplete development of these anchoring ligaments can lead to hypermobility and predispose the patient to torsion-related ischemic pathology. A prompt diagnosis is necessary to avoid life-threatening consequences of prolonged visceral ischemia. Abdominal torsions are rarely diagnosed clinically, and it is often the responsibility of the radiologist to recognize and make the diagnosis through radiography, fluoroscopy, or cross-sectional imaging. This article reviews the imaging spectrum (with radiologic-pathologic correlations) and therapeutic implications of gastrointestinal tract torsions.Torsion-related ischemic pathology may involve any portion of the gastrointestinal tract from the stomach to the colon. The clinical presentation of gastrointestinal tract torsion is nonspecific, and radiologists are relied on to make this diagnosis. Recognition of the predisposing factors and imaging spectrum of gastrointestinal tract torsions is essential to help direct timely intervention in these potentially life-threatening entities.

Pulmonary sclerosing hemangiomas are generally regarded as benign lung lesions arising from type II pneumocytes and bronchial epithelium. In some cases malignant features may be present. There are several case reports describing the radiographic, computed tomography (CT), and magnetic resonance imaging (MRI) characteristics of pulmonary sclerosing hemangiomas. Given the potential for low-grade malignancy 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging may be useful in the diagnostic work up and therapeutic planning in these patients, however the FDG–PET imaging features of pulmonary sclerosing hemangiomas are not well defined. We report a case of histopathologically diagnosed sclerosing hemangioma of the lung which demonstrated intermediate uptake of FDG on the preoperative PET/CT evaluation.

Bronchiolitis obliterans organizing pneumonia (BOOP) is a clinicopathologic syndrome occurring as a subacute or chronic respiratory illness characterized pathologically by masses of granulation tissue in the lumina of small airways, alveolar ducts, and some alveoli. Chest CT scan findings include ground-glass opacities or consolidations of variable size in a peripheral or peribronchial distribution. We present the clinicoradiological and pathological findings in a rarely described case of BOOP with pulmonary crospovidone deposits secondary to chronic aspiration of pharmaceutical tablets in a neurologically debilitated patient.

Blunt carotid and vertebral artery injury (BCVI) is a relatively rare injury reported in the civilian sector and is associated with high morbidity and mortality. The purpose of our study was to use an optimized computed tomography angiography protocol in the deployed setting to determine the prevalence of BCVI in a consecutive patient population having experienced recent wartime-related traumatic injuries. From July 2008 to September 2009, a total of 307 consecutive trauma patients were included in this study. At least 233 (76%) patients were known to have experienced blast-related traumatic injuries. 135 (44%) patients had injuries to the head, face, or neck. 4 patients (1.3%) sustained BCVI. There was no statistically significant difference between the prevalence of BCVI in the deployed setting and the civilian sector. We speculate that in our study population, the relatively decreased prevalence of cervical spinal fractures (3.3%) observed may counter the theoretical increased risk of vascular injury from blast trauma, ultimately producing a similar prevalence of overall BCVI compared to civilian study populations. Based on our observations, we cannot advocate for or against more liberalized screening of BCVI in the deployed setting, and military physicians may elect to continue screening for these injuries with currently established and accepted practice guidelines developed in civilian trauma populations.

The solid abdominal viscera are secured in place by various suspensory ligaments. Laxity or incomplete development of these anchoring ligaments can lead to hypermobility and predispose the patient to torsion-related ischemic pathology. The clinical symptoms of solid visceral intraabdominal torsions are nonspecific. A prompt diagnosis is critical to avoid life-threatening consequences of prolonged visceral ischemia. Abdominal torsions are rarely diagnosed clinically, and it is often the responsibility of the radiologist to recognize and make the diagnosis through cross-sectional imaging. This article reviews the imaging spectrum, radiologic-pathologic correlations, and therapeutic implications of solid visceral intraabdominal torsions, including some unusual solid organ and abdominal fat torsions.The clinical presentation of solid visceral intraabdominal torsion is nonspecific and radiologists are relied on to make this diagnosis on cross-sectional imaging studies. Recognition of the predisposing factors and imaging spectrum of intraabdominal torsions is essential to help direct timely intervention in these potentially life-threatening entities.

Multiple elements contribute to the stability of the anterior C1-C2 articulation, making this region subject to pathologies including trauma, inflammation, infection, and congenital deformities. C1-C2 instability places a patient at risk for significant neurologic compromise. Radiologic imaging plays a fundamental role in diagnosing atlantoaxial instability, indicating etiology, showing details of associated abnormalities, and providing information for planning treatment.

AJR 2009; 192:W36–W37 0361–803X/09/1921–W36 © American Roentgen Ray Society Intermetatarsal Fat Pad Sign: Radiographic Aid to Diagnosis of Occult Tarsometatarsal Joint Injuries Lisfranc tarsometatarsal fracture–disloc­ ations are well­described injuries usually resulting from forced plantar flexion or direct blow or crush trauma to the forefoot. Although this is a relatively rare injury, timely recognition is essential because misdiagnosis can lead to chronic pain and instability in this patient population. Lisfranc injuries account for less than 1% of all fractures and have a reported incidence of one per 55,000 persons; however, the overall incidence may be more common than is generally recognized because misdiagnosis has been reported to occur in approximately 20% of all cases [1, 2]. Conventional radiographs, including weight­ bearing­view images, can reveal fractures of the metatarsal bases, and dis placement of the bases in advanced cases, but can be unreli­ able in the detection of subtle injuries and iso lated ligamentous injuries without bone frac tures [3]. Subtle malalignment of the tarsal–metatarsal junction can be difficult to diagnose radiographically. Norfray et al. [4] have even suggested that 1–2 mm of tarso­ metatarsal malalignment may be normal. The reason for this diagnostic dilemma lies in the fact that overlapping shadows, inappropriate positioning, and sub optimal exposure parame­ ters can make correct evaluation of osseous land marks difficult [4]. Despite its limitations in revealing the full extent of tarsometatarsal injury, radiography is often the first examination performed after the initial clinical examination. Mis diagnosis is highest in cases of isolated ligamentous injury with no visible fracture on the radiograph and in which metatarsal cuneiform offset may be subtle or absent. We have pro­ vided images of such a case, and we describe an interesting soft­tissue radiographic find­ ing that, to the best of our knowledge, has not been previously described. We have called this the “intermetatarsal fat pad sign.” Similar to the sail sign of olecranon and coronoid fossae fat pad displacement seen with intra­ articular injury to the elbow, we show that edema and hemorrhage from a Lisfranc ligamentous injury may also produce a radio­ graphically apparent displaced inter metatarsal fat pad (Fig. 1). We believe that awareness of the intermetatarsal fat pad sign may be of aid in the diagnosis of subtle radio graphic pre­ sentations of Lisfranc injury. Vincent Timpone Michael Tall Andrew Puckett David Grant U.S. Air Force Medical Center Travis Air Force Base, CA 94535