Copyright2022 ThriveAP Inc., All Rights Reserved, Key Advice for NPs & PAs with Angela Golden, DNP, FNP-C, FAANP, FOMA, Evidence-Based Wound Care for Advanced Practice Providers, Featured ThriveAP Faculty: Benjamin Smith, DMSc, PA-C, DFAAPA, Finding Your Why with ThriveAP Speaker Steven Wei, EdD, MPH, MS, PA-C, DFAAPA. Although it is a clinical diagnosis, imaging is a powerful adjunct to facilitate early diagnosis in equivocal cases. Before Metformin should be held for 48 hours after the administration of IV contrast, and resumed only after serum creatinine returns to baseline levels, according to the U.S. Food and Drug Administration. Clipboard, Search History, and several other advanced features are temporarily unavailable. Cellulitis occurs after disruption of the skin and invasion of the subcutaneous tissues by microorganisms that may be skin flora, such as beta-haemolytic streptococci (most often),Staphylococcus aureus(including methycillin-resistant), or other bacteria 9. Most centers use nonionic contrast agents (which are generally low osmolality) for IV contrast studies.5 The rate of major reactions (e.g., anaphylaxis, death) is the same for ionic and nonionic IV contrast agentsan estimated one in 170,000 administrationsbut nonionic contrast has a lower rate of minor reactions.6 Approximately 5% to 12% of patients who receive high-osmolality contrast have adverse reactions, most of which are mild or moderate.7 Use of low-osmolality contrast has been associated with a reduction in adverse effects. PDF CT Exams Contrast vs Non-Contrast Guide - Oregon Imaging American College of Radiology ACR Appropriateness Criteria Sinonasal Negative studies or nonspecific findings in the context of high clinical suspicion for necrotizing fasciitis, should be treated promptly as this is a clinical diagnosis. The choice of contrast agent depends on route of administration, desired tissue differentiation, and suspected diagnosis. Soft-tissue gas is seen at the lateral aspect of the left knee along the fascial planes on the radiograph. If the infection spreads to deeper tissues, soft-tissue abscess, infectious myositis, necrotizing fasciitis, and osteomyelitis can all be detected with CT. MRI is sensitive for distinguishing cellulitis alone from necrotizing fasciitis and infectious myositis and for showing subcutaneous fluid collections and abscesses. Radiographics. A 57-year-old diabetic male with pneumoscrotum. Clinical findings suggestive of necrotizing fasciitis vs cellulitis.7, There have been association with intravenous drug use as well as chronic conditions including diabetes mellitus, immunosuppression, obesity, and peripheral vascular disease.3, 8 A history of recent surgery (within the past 90 days) at the affected site has been shown to be a strong predictor for necrotizing fasciitis.7, Infection typically begins in the superficial fascial planes, then rapidly progress into the deep fascial layers, which causes necrosis secondary to microvascular occlusion.1 The rate of spread of infection is directly proportional to the thickness of the subcutaneous layers, with fastest spread seen in the lower extremities due to the lack of fibrous boundaries between subcutaneous tissue and fascia.2, 9, Necrotizing fasciitis is a clinical diagnosis since imaging findings can be nonspecific or unremarkable early in the course of the disease.1 The majority of cases are initially misdiagnosed, causing delay in diagnosis.10 Imaging appearances of necrotizing fasciitis can also overlap with other conditions, including nonnecrotizing fasciitis, dermatomyositis, graft vs host disease, or ischemic myonecrosis.1 The main utility of imaging is to determine the extent of the soft-tissue infection as well as to guide surgical planning.1, 8 If the patient is presenting with shock, imaging should not delay the initiation of treatment.1 Definitive diagnosis is based on surgical exploration and biopsy and aggressive surgical fasciotomy of necrotic tissue is required to prevent the spread of infection.7, Early findings of necrotizing fasciitis on radiography can appear similar to cellulitis including soft-tissue opacity and thickening.1113 The classical findings of dissecting gas along fascial planes in the absence of trauma is a specific sign, but is only seen in 24.855.0% of patients, and may not be seen until late in the disease (Figures 1 and 2).1, 10,12 Necrotizing fasciitis commonly affects the lower extremities, with involvement of the perineum or scrotum, classically known as Fourniers gangrene (Figure 3).3, 14,15 Soft-tissue gas is typically caused by gas-forming anaerobic infections, although this may not be present in diabetic patients.16 As such, the absence of soft-tissue emphysema does not exclude a diagnosis of necrotizing fasciitis.1. PDF CT EXAM CPT CODE REFERENCE - Wake Radiology Recent studies suggest that a combination of hydration, sodium bicarbonate, N-acetylcysteine, and decreased contrast volume may reduce this risk in high-risk populations.14,15, The question of whether this risk has been overstated has been raised in the medical literature. The American College of Radiology proposes a three-tiered risk assessment for patients receiving metformin in whom IV contrast is to be administered (Table 3).7 Many institutions have their own protocols for metformin administration with IV contrast, so physicians should be aware of the standard of care in their community. The parapharyngeal space was the most commonly involved space. Epub 2017 Mar 30. Insights Imaging. The soft-tissue air deep to the fascia is seen as multiple echogenic foci (arrows) on ultrasound study (b). Computed tomography (CT) with and without contrast: indications and protocols. Spinnato P, Patel DB, Di Carlo M, Bartoloni A, Cevolani L, Matcuk GR, Cromb A. Microorganisms. Weaver JS, Omar IM, Mar WA, Klauser AS, Winegar BA, Mlady GW, McCurdy WE, Taljanovic MS. Pol J Radiol. In a patient with colon cancer undergoing a workup for metastases, axial CT without contrast (A) shows prominence of the right hilar region (arrow). Although a very uncommon soft-tissue infection, it has significant mortality up to 7080% and constitutes a life-threatening surgical emergency.1, 2 The most important predictor of mortality is a delay in diagnosis, thus it is essential to make a prompt diagnosis.2 Clinically, the findings of necrotizing fasciitis can overlap with other soft-tissue infections including cellulitis, abscess or even compartment syndrome, but pain out of proportion to the degree of skin involvement and signs of systemic shock should alert the clinician to the possibility of necrotizing fasciitis.46 Other red flag clinical findings are listed in Table 1. 2004;350(9):904-12. CT without contrast in a patient with a history of interstitial lung disease and right lung transplant shows the patent but partially narrowed anastomotic site of the right bronchus (A) (red arrow). 1994;192(2):493-6. Since the epidermis is not involved, cellulitis is not transmitted by person-to-person contact. Ultrasound is helpful to rule out deep venous thrombosis, assess for possible foreign bodies, and guide potential diagnostic fluid aspiration.8, 13 Sensitivity of ultrasound for the diagnosis of necrotizing fasciitis is 88.2%, with a specificity of 93.3%.20, CT is the primary imaging modality in the work-up of necrotizing fasciitis given its wide availability and high spatial resolution compared to radiography or ultrasound.3 Soft-tissue gas is a pertinent CT finding, but absence of it should not exclude the diagnosis of necrotizing fasciitis if clinically suspected.1, 2,11,17 Gas within fluid collections along subfascial planes is the hallmark of necrotizing fasciitis (Figures 5 and 6).11, 21 The lack of soft-tissue gas on CT may be due to early disease, aerobic infections, or if the patient is diabetic.1, 16 The sensitivity of CT in diagnosing necrotizing fasciitis is 80%, but it lacks specificity as findings can also be seen in nonnecrotizing fasciitis.21, 22 Thickening and nonenhancement of the fascia on contrast-enhanced CT may be helpful to distinguish from nonnecrotizing fasciitis.2 Subfascial and intermuscular fluid accumulation can also be seen on CT, and may represent early findings of necrotizing fasciitis (Figure 7).21. JAMES V. RAWSON, MD, AND ALLEN L. PELLETIER, MD. [18F]Fluoride Positron-Emission Tomography (PET) and [18F]FDG PET for Assessment of Osteomyelitis of the Jaw in Comparison to Computed Tomography (CT) and Magnetic Resonance Imaging (MRI): A Prospective PET/CT and PET/MRI Pilot Study. MR Imaging in Acute Infectious Cellulitis. T2 weighted image with fat saturation of the left thigh demonstrates a large area of myonecrosis within the proximal rectus femoris muscle, with extensive muscular, fascial, and subcutaneous enhancement and edema, with crescentic fascial fluid collections, predominantly around the rectus femoris and sartorius, suggestive of necrotizing fasciitis. An official website of the United States government. Different imaging modalities require different concentrations of contrast for optimal detection of pathology. Inclusion in an NLM database does not imply endorsement of, or agreement with, What is the rationale for the laboratory workup for suspected pheochromocytomas and paragangliomas? BMJ. Computed Tomography (CT or CAT) Scan of the Abdomen The diagnostic algorithm for lung cancer screening is evolving. Preparation: Please have only a clear liquid diet for 4 hours prior to exam. N/A No CT WRIST LEFT WO CONTRAST (IMG3906) CT WRIST RIGHT WO CONTRAST(IMG3909) CT HAND LEFT WO CONTRAST (IMG3794) CT HAND RIGHT WO CONTRAST (IMG3797) 73200 When does chest CT require contrast enhancement? thickening of skin and superficial fascia, diffuse subcutaneous linear/reticular or ill-defined hyperintensity tending to collect at the hypodermis, contrast enhancement differentiates cellulitis from stasis oedema, areas of necrotising cellulitis do not enhance, degree of enhancement depends on the post contrast delay. 2009;39(10):957-71. Gk MC, Turhan Y, Demirolu M, Kl B, Akku M, zkan K. Radiological assessment in necrotizing fasciitis. Cellulitis treatment usually includes a prescription oral antibiotic. Pitfalls of CT for deep neck abscess imaging assessment: a Moran CORE | Preseptal vs Orbital Cellulitis - University of Utah FOIA In later stages, nonenhancement of the fascia may be seen due to necrosis, which can be helpful to differentiate from nonnecrotizing fasciitis.3, 28,29, Although more apparent on CT, gas in the soft tissues is represented by punctate or curvilinear T1 and T2 low signal with corresponding blooming artifact on gradient echo sequences.1, 18,25,30 Although a highly specific finding, the absence of soft-tissue gas does not exclude the diagnosis of necrotizing fasciitis.3, 11. 70470 Metastases/Known cancer HIV Intracranial infection Note: CT can be used if there are contraindications for MRI. NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. Children have a lower incidence of reactions to IV contrast agents, and most of these are mild (0.18% for low-osmolality agents).7,8, Risk factors for contrast reactions include multiple drug allergies and asthma. {"url":"/signup-modal-props.json?lang=gb"}, Radswiki T, Carroll D, Knipe H, et al. The https:// ensures that you are connecting to the Wysoki MG, Santora TA, Shah RM, Friedman AC. 2020;368:m710. In general, oral contrast is used for most abdominal and pelvic CT scans unless there is no suspicion of bowel pathology (e.g., noncontrast CT to detect kidney stones) or when administration would delay a diagnosis in the trauma setting. Copyright 2013 by the American Academy of Family Physicians. Typically, CT focusing on vascular disease (e.g., aneurysm, dissection) or renal or pancreatic pathology may include noncontrast-enhanced images to identify calcifications.20 Contrast-enhanced studies would be performed on the same day, in the same setting. Cellulitis | Radiology Reference Article | Radiopaedia.org Case 1: orbital and periorbital cellulitis, see full revision history and disclosures. This question is for testing whether or not you are a human visitor and to prevent automated spam submissions. Additionally, systemic features such as fevers and rigors may also be present. Swartz M. Clinical Practice. No circumscribed collection, or signs of bulbar or intraconal involvement (note the preservation of the normal intraorbital fat density). Sinus radiographs, which were also obtained, were not helpful in diagnosis or management. Cellulitis. Before Even in osseous infection, CT and MRI can give better anatomic delineation of the extent of infection. doi: 10.5114/pjr.2022.113825. Normally the subcutaneous tissue is hypoechoic with few hyperechoic strands (representing connective tissue). For the assessment of vascular disease, CT in most cases requires IV contrast to delineate the vessel lumen. <>/Metadata 2 0 R/ViewerPreferences 6 0 R>> myriad of non-infective erythematous rashes, ADVERTISEMENT: Supporters see fewer/no ads, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. In cases where the plain film and nuclear medicine bone scan findings are complicated due to previous surgery, trauma, or underlying illness, the anatomic resolution and soft tissue contrast provided by MRI and CT are often necessary to determine if underlying infection exists. Computed tomography (CT scan or CAT scan) is a noninvasive diagnostic imaging procedure that uses a combination of X-rays and computer technology to produce horizontal, or axial, images (often called slices) of the body. The American College of Radiology Appropriateness Criteria is a useful online resource. If you have questions about ordering your patient's CT, we encourage you to speak with a radiologist about the study and the need for contrast. The U.S. Food and Drug Administration advises that metformin should be withheld at the time of IV contrast administration and for 48 hours afterward, and resumed only after reevaluation of renal status (i.e., return to baseline serum creatinine level).13. Federal government websites often end in .gov or .mil. MRI's visualization of the bone marrow allows for the sensitive detection of osteomyelitis, although specificity for the diagnosis of osteomyelitis is aided by other findings, including cortical destruction. endobj sharing sensitive information, make sure youre on a federal 2001;176(5):1155-9. The need for enhancement with intravenous (IV) contrast depends on the specific clinical indication (Table 1). . It results in pain, erythema, edema, and warmth. However, patients with a documented anaphylactic reaction to any medication are at higher risk of a reaction to iodinated contrast.9,10, Many centers screen outpatients with suspected renal insufficiency by measuring serum creatinine one month before administration of contrast agents. Large volume of gas seen within the scrotum wall and scrotum sac on the scout image (curved black arrow), consistent with Fourniers gangrene. Muscular fascia lies deep to the subcutaneous layer. 6. Clear communication between the physician and radiologist is essential for obtaining the most appropriate study at the lowest cost and risk to the patient. Infection, inflammation, and edema of the lung parenchyma are usually well depicted on CT without contrast enhancement. The site is secure. Premedication with antihistamines and corticosteroids is recommended in patients with a history of mild to moderate reactions to intravenous contrast agents. Given that metformin is excreted through the kidneys, IV contrast may impair metformin clearance from the body putting the patient at risk for metabolic acidosis. Unable to process the form. government site. Many practices have their own protocols for IV dye administration in patients using metformin so nurse practitioners must familiarize themselves with these policies. N.p. Answer (1 of 4): You asked: Are CT scans without contrast always done before CT scans with contrast? Magn Reson Imaging Clin N Am. Reinert CP, Pfannenberg C, Dittmann H, Gckel B, la Fougre C, Nikolaou K, Hoefert S. J Clin Med. Cellulitis. Risk factors include chronic kidney disease, diabetes mellitus, heart failure, older age, anemia, left ventricular systolic dysfunction, and contrast volume. PDF CT SCANS AND IV CONTRAST UTILIZATION - United Radiology Group, Chartered Cellulitis can affect any region of the body, and commonly affects a lower limb. N Engl J Med. A neck mass or adenopathy also may be investigated, particularly when it results in airway or vascular compromise. Adams, James, and Erik D. Barton. It results in pain, erythema, oedema, and warmth. Radiology. Because there is a risk of aspiration-induced pulmonary edema with concentrated iodine-based contrast agents, patients must be carefully selected. We do not capture any email address. Contrast-related nephrotoxicity has been reported,11 although this has been challenged more recently.12 Suspected risk factors for this complication include advanced age, cardiovascular disease, treatment with chemotherapy, elevated serum creatinine level, dehydration, diabetes, use of nonsteroidal anti-inflammatory medications, myeloma,13 renal disease, and kidney transplant. A history of anaphylactic reactions would preclude IV contrast except in extreme emergencies. %PDF-1.7 CT is the most sensitive modality for soft-tissue gas detection, and compared with radiography, CT is superior to evaluate the extent of tissue or osseous involvement, show an underlying (and potentially more remote) infectious source, and reveal serious complications such as vascular rupture complicating tissue necrosis [ 10, 13 - 20 ]. T2 weighted images with fat saturation demonstrates extensive high signal within the intermuscular septa surrounding the gastrocnemius and soleus muscle bellies suggestive of subfascial fluid (white arrows). Horton L, Jacobson J, Powell A, Fessell D, Hayes C. Sonography and Radiography of Soft-Tissue Foreign Bodies. See permissionsforcopyrightquestions and/or permission requests. Related editorial: Potential Harms of Computed Tomography: The Role of Informed Consent. Fundic gland polyps: Should my patient stop taking PPIs? Sign In to Email Alerts with your Email Address. AJR Am J Roentgenol. Interstitial lung disease 2. Skeletal Radiol. Cellulitis (rare plural: cellulitides) is an acute infection of the dermis and subcutaneous tissues without deep fascial or muscular involvement. Evaluation of chronic obstructive pulmonary disease also does not require IV contrast. 8600 Rockville Pike Uncomplicated cellulitis is usually treated conservatively with antibiotics and locally supportive measures. Zacharias N, Velmahos GC, Salama A, Alam HB, de Moya M, King DR, et al.. Order "WRIST" if only carpal area. Accessibility Ultrasound is usually the first investigation to evaluate a clinical suspicion of cellulitis. Fugitt JB, Puckett ML, Quigley MM, Kerr SM. Laryngeal edema (severe or rapidly progressing), Methylprednisolone (Medrol), 32 mg orally 12 and 2 hours before contrast administration; plus diphenhydramine (Benadryl), 50 mg intravenously, intramuscularly, or orally 1 hour before contrast administration, Prednisone, 50 mg orally 13, 7, and 1 hour before contrast administration; plus diphenhydramine, 50 mg intravenously, intramuscularly, or orally 1 hour before contrast administration, Normal renal function and no comorbid disorder, Metformin (Glucophage) can be continued when contrast is administered; serum creatinine does not need to be measured, Normal renal function and at least one comorbid disorder, Metformin should be discontinued when contrast is administered; if the patient remains clinically stable and has no new intercurrent risk factors for renal impairment, metformin may be resumed in 48 hours without repeating serum creatinine measurement, Metformin should be discontinued when contrast is administered; resume only after careful reevaluation and monitoring of renal status, Noncontrast-enhanced CT of the head is the preferred initial study if performed within three hours of acute symptom onset; contrast-enhanced CT should be obtained for patients with symptoms lasting longer than three hours; contrast-enhanced CT combined with CT angiography of the neck may be needed for follow-up, Thin section high-resolution CT without contrast, Extremity soft tissue swelling, infection, or trauma, Contrast is necessary if vascular involvement or injury is suspected, Scan suspected area of trauma in cervical, thoracic, or lumbar spine, Abdominal and pelvic CT; oral or rectal contrast agent based on institutional preference, Protocols vary depending on cancer type and stage, Diverticulitis; suspected complications of inflammatory bowel disease, Intravenous contrast agent for diverticulitis; oral and/or rectal contrast agent can be administered to visualize bowel, Noncontrast-enhanced CT is sensitive for calcifications (chronic pancreatitis); contrast-enhanced CT is best for evolving pancreatitis or pancreatic pseudocyst, Many centers now include venous phase CT of the pelvis and lower extremities in combination with CT angiography of the lung. Your email address will not be published. 5. Thirteen orbital computed tomographic (CT) scans were obtained in 12 patients with postseptal (orbital) cellulitis. Since the epidermis is not involved, cellulitis is not transmitted by person-to-person contact. Patients with a mild allergy may be pre-medicated with an antihistamine or steroids before imaging. myriad of non-infective erythematous rashes, Please Note: You can also scroll through stacks with your mouse wheel or the keyboard arrow keys. Postseptal cellulitis: CT in diagnosis and management - PubMed Unable to load your collection due to an error, Unable to load your delegates due to an error. However, contrast may be helpful if there are concerns about complications such as chest wall involvement, where contrast enhancement may help further delineate the extent of complications. Rahmouni A, Chosidow O, Mathieu D et al. Thank you for your interest in spreading the word on Cleveland Clinic Journal of Medicine. Diffuse thickening of the superficial fascia, which can be seen in the early phase of necrotizing fasciitis (c). Summary of imaging findings of necrotizing fasciitis. At the time the article was created The Radswiki had no recorded disclosures. Unable to process the form. 2015;2015:587857. doi: 10.1155/2015/587857. Next imaging study. Magnetic resonance imaging differentiates between necrotizing and non-necrotizing fasciitis of the lower extremity. 1 0 obj CT is used to accurately differentiate between superficial cellulitis and deep cellulitis. A ct urogram uses IV contrast (dye) to better evaluate the renal pelvis and ureter (the "tube" connecting your kidneys t. Read More. Ultrasound is usually the first investigation to evaluate a clinical suspicion of cellulitis. Necrotizing Fasciitis and Its Mimics: What Radiologists Need to Know Soft-tissue gas is a specific finding on all modalities, but is not present in all patients with necrotizing fasciitis. Unenhanced CT is also used in patients with spine and extremity trauma. This content is owned by the AAFP. Necrotizing fasciitis is a rapidly spreading soft tissue infection involving the deep fascial layers, which can cause secondary necrosis leading to significant morbidity and mortality.13 It most commonly affects the lower extremities accounting for approximately 50% of cases, and can affect different body parts including the perineum (as in Fourniers gangrene), and submandibular region (as in Ludwig angina). Below is an overview of the following CTA studies and their indications: Regardless of the pathology youre looking for, contrast isnt right for everyone. 2. Address correspondence to: Dr David K Tso. Emerg Radiol. 3. Bethesda, MD 20894, Web Policies Unauthorized use of these marks is strictly prohibited. Stadelmann VA, Potapova I, Camenisch K, Nehrbass D, Richards RG, Moriarty TF. 1994;192(2):493-6. When the neoplasm has CT attenuation similar to that of adjacent structures (lymph nodes in the hilum, masses in the mediasti-num or chest wall), IV contrast can improve identification of the lesion and delineation of its margins and the relationship with adjacent structures (eg, vascular structures) (Figure 1). National Library of Medicine All Rights Reserved. It is usually due to underlying bacterial sinusitis. Careers. 7. 3 However, IV radiologic contrast may cause transient alteration in renal function, which could impair metformin clearance, leading to a higher risk of metabolic acidosis. Brothers TE, Tagge DU, Stutley JE, Conway WF, Del Schutte H, Byrne TK. Signs of cellulitis are easy to appreciate on CT and MRI and include thickening of the fat, best appreciated on the preseptal space, fat infiltration, and contrast enhancement. HHS Vulnerability Disclosure, Help 2009;16(4):267-76. ADVERTISEMENT: Supporters see fewer/no ads. Barium suspension from fluoroscopy or CT will not produce an artifact on abdominal magnetic resonance imaging. government site. The most common contrast agents used with CT imaging are barium- and iodine-based. These reactions are relatively rare and are usually mild but occasionally can be severe.9 Anaphylactoid reactions have an unclear etiology but mimic allergic reactions, and they are more likely to occur in patients with a previous reaction to contrast and in patients with asthma or cardiovascular or renal disease. In certain situations, however, a contrast medium is essential. During the injection you may feel flushed and get a metallic taste in your mouth. In B, the native left lung is small, with evidence of bronchiectasis, bronchiolectasis, and areas of honeycombing (black arrow). In particular, the evaluation of soft tissue infections, including cellulitus, myositis, fasciitis, abscess, and septic arthritis are often best evaluated by MRI or CT due to their excellent anatomic resolution and soft tissue contrast. Cellulitis | Radiology Reference Article | Radiopaedia.org A 39-year-old-male with necrotizing fasciitis of the right thigh. Yes neuro CTa HeaD Circle of Willis CTA Head with and without contrast Note: MRA Brain without contrast is preferred. the contents by NLM or the National Institutes of Health. Peri-orbital and orbital cellulitis - BMJ Best Practice High Resolution Chest CT This is a specialized CT of the lungs performed without IV contrast. In B, the native left lung is small, with evidence of bronchiectasis, bronchiolectasis, and areas of honeycombing (black arrow). 30 0 obj Muscular fascia lies deep to the subcutaneous layer. 3 0 obj FOIA Nonanaphylactoid reactions are dependent on contrast osmolality and on the volume and route of injection (unlike anaphylactoid reactions).10 Typical symptoms include warmth, metallic taste, and nausea or vomiting. Cellulitis can affect any region of the body, and commonly affects a lower limb. 2021 Feb 1;94(1118):20200648. doi: 10.1259/bjr.20200648. Contrast-enhanced CT demonstrates air (arrows) and edema in the scrotum, surrounding the right testicle (a). official website and that any information you provide is encrypted Cellulitis - Diagnosis and treatment - Mayo Clinic Occasionally sepsis may result. Iodinated contrast agents can cause reversible acute renal failure. CT is helpful in guiding surgical debridement and drainage by evaluating the extent of soft tissue and osseous involvement, identifying the potential infectious source and identifying potential complications including vascular rupture or tissue necrosis.1, 2,13,22 MAGNETIC RESONANCE IMAGING Patients with history of anaphylactic reaction should not receive contrast. We are grateful for the editorial assistance of Megan M. Griffiths, scientific writer for the Imaging Institute, Cleveland Clinic. Kirchgesner T, Tamigneaux C, Acid S et al. Miller TT, Randolph DA, Staron RB, Feldman F, Cushin S. Fat-suppressed MRI of musculoskeletal infection: fast T2-weighted techniques versus gadolinium-enhanced T1-weighted images, Necrotizing fasciitis: unreliable MRI findings in the preoperative diagnosis, Differentiation of necrotizing fasciitis and cellulitis using MR imaging.