Working in the emergency department as a nurse practitioner, I order CT scans in my evaluation of patients every day. Yu J & Habib P. MR Imaging of Urgent Inflammatory and Infectious Conditions Affecting the Soft Tissues of the Musculoskeletal System. , Acuterecurrent rhinosinusitis At the time the article was last revised David Carroll had AJR Am J Roentgenol. Muscular fascia lies deep to the subcutaneous layer. In patients with normal renal function, repeat measurement of serum creatinine is not recommended after outpatient administration of intravenous contrast agents. Oral contrast can be administered through a nasogastric tube to minimize the risk of aspiration. Clear communication between the physician and radiologist is essential for obtaining the most appropriate study at the lowest cost and risk to the patient. Subcutaneous and subfacial emphysema, which are classical finding of necrotizing fasciitis (a). During the injection you may feel flushed and get a metallic taste in your mouth. Cellulitis occurs after disruption of the skin and invasion of the subcutaneous tissues by microorganisms that may be skin flora, such as beta-hemolytic streptococci (most often),Staphylococcus aureus(including methycillin-resistant), or other bacteria 9. Fortunately, orbital fat provides intrinsic background contrast, and most orbital pathologies can be easily visualised without infusion of a contrast medium. Order "HAND" if entire wrist and hand. Contrast can cause acute renal failure. It results in pain, erythema, edema, and warmth. We do not capture any email address. This site needs JavaScript to work properly. Almost always, CTs should be ordered with or without contrast, not both. Contrast enhancement is also used to evaluate superior vena cava syndrome. 5. What is the rationale for the laboratory workup for suspected pheochromocytomas and paragangliomas? Contrast-enhanced CT demonstrates crescentic subfascial fluid (arrow) with fluid also seen superficial to the fascia (arrow head) and between muscle planes (a). Wall DB, Klein SR, Black S, de Virgilio C. A simple model to help distinguish necrotizing fasciitis from nonnecrotizing soft tissue infection. CT scanning is often the first imaging modality that is used because of its ease and availability at most medical institutions. Accessibility The diagnostic algorithm for lung cancer screening is evolving. Schmid M, Kossmann T, Duewell S. Differentiation of Necrotizing Fasciitis and Cellulitis Using MR Imaging. Normally the subcutaneous tissue is hypoechoic with few hyperechoic strands (representing connective tissue). Citation, DOI, disclosures and article data. Ultrasound is usually the first investigation to evaluate a clinical suspicion of cellulitis. Below is an overview of the following CTA studies and their indications: Regardless of the pathology youre looking for, contrast isnt right for everyone. A neck mass or adenopathy also may be investigated, particularly when it results in airway or vascular compromise. Mediastinitis may likewise be iatrogenic or may spread from the oropharynx. If the infection spreads to deeper tissues, complications can occur, such as soft-tissue abscess,necrotising fasciitis,infectious myositis, and/or osteomyelitis. Shortness of breath Abdomen andPelvis Without IV contrast 1. A 55-year-old male with necrotizing Fasciitis of the left thigh. Correlation of histopathologic findings with clinical outcome in necrotizing fasciitis. It is injected through an intravenous line during the examination. At our institution, the CT protocol includes concomitant injections in the upper-extremity veins, with imaging timed for venous phase enhancement (pulmonary venogram). It is essential to know the types of contrast agents, their risks, contraindications, and common clinical scenarios in which contrast-enhanced computed tomography is appropriate. 6. eCollection 2022. MRI Nomenclature for Musculoskeletal Infection. Axial non-contrast. Patients with a mild allergy may be pre-medicated with an antihistamine or steroids before imaging. Clear communication between the physician and radiologist is essential for obtaining the most appropriate study at the lowest cost and risk to the patient. 2009;39(10):957-71. Swartz M. Clinical Practice. Family physicians often must determine the most appropriate diagnostic tests to order for their patients. 8. endstream 2001;176(5):1155-9. DOI: https://doi.org/10.3949/ccjm.83a.15037, Computed tomography: revolutionizing the practice of medicine for 40 years, ACR-SCBT-MR-SPR practice parameter for the performance of thoracic computed tomography (CT), Screening for lung cancer: US Preventive Services Task Force recommendation statement, Solitary pulmonary nodules: dynamic enhanced multi-detector row CT study and comparison with vascular endothelial growth factor and microvessel density, High-pitch ECG-synchronized pulmonary CT angiography versus standard CT pulmonary angiography: a prospective randomized study, Intravenous contrast medium administration and scan timing at CT: considerations and approaches, Emergency imaging assessment of acute, nontraumatic conditions of the head and neck, Iodinated contrast media and their adverse reactions, ACR Committee on Drugs and Contrast Media, ACR Manual on Contrast Media. If the infection spreads to deeper tissues, soft-tissue abscess, infectious myositis, necrotising fasciitis, and osteomyelitis can all be detected with CT. MRI is sensitive for distinguishing cellulitis alone from necrotising fasciitis and infectious myositis and for showing subcutaneous fluid collections and abscesses. Although many radiology departments screen for shellfish allergy, there is no cross-reactivity between shellfish and iodinated contrast. A 47-year-old male with necrotizing fasciitis of the left thigh. 1. 30 0 obj [ 16, 17, 18] On CT scans, a preseptal cellulitis may appear as. 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). 5. 1994;192(2):493-6. Insights Imaging. 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. . An official website of the United States government. A 39-year-old-male with necrotizing fasciitis of the right thigh. Emergency Medicine: Clinical Essentials. Cellulitis. 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. official website and that any information you provide is encrypted sonographic hallmarks of cellulitis include abnormal echogenicity and increased thickness of the dermis with indistinct "haziness" and increased echogenicity of the subcutaneous tissue, it is often helpful to compare the area in question to the (presumably normal)contralateral side, progressive accumulation of edema in the subcutaneous tissue appears as branching, anechoic striations which impart a lobulated ("cobble-stone" appearance), presence of thickened and abnormally echogenic overlying skin will favor cellulitis over edema, linear anechoic bands of fluid deep to the subcutaneous layer favor lymphedema, ultrasound is more sensitive than MRI for the detection of a retained foreign body as the causative agent, especially if small and wooden 4,5. AJR Am J Roentgenol. 1998;170(3):615-20. Fasciae of the Musculoskeletal System: MRI Findings in Trauma, Infection and Neoplastic Diseases. Before Barium suspensions are not nephrotoxic and can be used safely in patients with renal failure. 07/16 RH /MF Interstitial lung disease 2. Abdominal and/or pelvic pain-acute or chronic 2. Axial CT with contrast enhancement obtained subsequently (B and C) shows that this abnormality corresponds to right hilar lymphadenopathy partially encasing the right pulmonary artery (arrows). 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. No mutagenic or teratogenic effects have been shown with nonionic, low-osmolality contrast in animal studies. The overall PPV for the prediction of deep neck abscess with contrast-enhanced CT was 79.6%. Fasciae of the Musculoskeletal System: MRI Findings in Trauma, Infection and Neoplastic Diseases. A 39-year-old male with necrotizing fasciitis of the right ankle. 2019;10(1):47. Imaging of Musculoskeletal Soft Tissue Infections. Dr. Amy Levine answered. No circumscribed collection, or signs of bulbar or intraconal involvement (note the preservation of the normal intraorbital fat density). CT may also be ordered for cross-sectional images of the spine with contrast in the thecal sac. CT Head or brain with and without contrast Note: MRI Brain with/without contrast is preferred. Extensive streaky soft-tissue gas is seen extending along the fascial planes of the right thigh on radiograph. At the time the article was created The Radswiki had no recorded disclosures. The decision to order contrast-enhanced CT is based on the clinical question being asked. While the plain film and nuclear medicine bone scan are still the traditional imaging modalities used in the evaluation of musculoskeletal infection, the cross-sectional imaging modalities, computed tomography (CT) and magnetic resonance imaging (MRI), have become critical in the delineation of many types of musculoskeletal infection. Rahmouni A, Chosidow O, Mathieu D et al. It results in pain, erythema, oedema, and warmth. MR Imaging in Acute Infectious Cellulitis. 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. Biomed Res Int. Oral contrast agents are barium- or iodine-based and are used for bowel opacification. 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). endobj In the emergency setting, CT of the neck is often performed to investigate symptoms of acute infection or inflammation or symptoms of aerodigestive tract compromise referable to the neck. 2021;50(12):2319-47. In uncomplicated cellulitis, CT demonstrates skin thickening, septation of the subcutaneous fat, and thickening of the underlying superficial fascia. Radiology. Infect Dis Clin North Am. 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. Contrast enhancement of the pulmonary arteries is key, as embolic disease is identified as abnormal filling defects within the pulmonary arteries (Figure 2). 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. A 53-year-old male with necrotizing fasciitis of the left knee. 2. Because there is a risk of aspiration-induced pulmonary edema with concentrated iodine-based contrast agents, patients must be carefully selected. Skeletal Radiol. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, organs, and blood vessels. 2001 Oct;42(4-5):259-305. 2022 Nov 25;10(12):2329. doi: 10.3390/microorganisms10122329. 2009;16(4):267-76. Cross-sectional imaging findings include asymmetric thickening of fascia, soft tissue air, blurring of fascial planes, inflammatory fat stranding, reactive lymphadenopathy, and nonenhancement of muscular fascia. Above this, there is a narrow, relatively hyperechoic epidermal-dermal layer. 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. CT pulmonary angiography with intravenous contrast in a patient being evaluated for arteriovenous malformation. The concentration of barium used for fluoroscopy is more than 20 times that of the typical oral contrast suspension for CT. For example, the barium concentration from an upper gastrointestinal series or an enema will produce an artifact on abdominal CT because it is significantly more concentrated than bowel contrast agents used for CT. Barium enemas are also given after abdominal CT to allow time for the less-dense barium to leave the colon. 2004;350(9):904-12. In Vivo MicroCT Monitoring of Osteomyelitis in a Rat Model. This is commonly ordered for diagnosis of: 1. Possible reactions are listed in Table 1.7 If a patient has had a previous minor reaction to an IV iodinated contrast agent, precontrast administration of oral or IV corticosteroids and diphenhydramine (Benadryl) may decrease their risk (Table 27 ). A 64-year-old male with Fourniers gangrene with perforated diverticulitis. Disease processes that involve calcifications may benefit from noncontrast-enhanced images because contrast may mask the appearance of calcifications. Horton L, Jacobson J, Powell A, Fessell D, Hayes C. Sonography and Radiography of Soft-Tissue Foreign Bodies. 4 0 obj CT area of interest without IV contrast Usually Appropriate Varies Variant 7: Suspected soft tissue infection. 4. 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. 1998;170(3):615-20. Preparation: Please have only a clear liquid diet for 4 hours prior to exam. The .gov means its official. Epub 2015 Apr 29. In cases of question, Computed tomography (CT) with and without contrast of the orbits and sinuses should be ordered to look for evidence of post-septal involvement. The https:// ensures that you are connecting to the Adams, James, and Erik D. Barton. 2022 Mar 5;87:e141-e162. Many practices have their own protocols for IV dye administration in patients using metformin so nurse practitioners must familiarize themselves with these policies. It is injected through an intravenous line during the examination. Weaver JS, Omar IM, Mar WA, Klauser AS, Winegar BA, Mlady GW, McCurdy WE, Taljanovic MS. Pol J Radiol. In pleural effusion, CT assessment for the presence, location, and extent of the effusion does not require contrast. The most common contrast agents used with CT imaging are barium- and iodine-based. Gk MC, Turhan Y, Demirolu M, Kl B, Akku M, zkan K. Radiological assessment in necrotizing fasciitis. All Rights Reserved. Chaudhry AA, Baker KS, Gould ES, Gupta R. Necrotizing fasciitis and its mimics: what radiologists need to know, Musculoskeletal infection: role of CT in the emergency department. Required fields are marked *. 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. Mitchell C, Dolan N, Drsteler K. Management of Dependent Use of Illicit Opioids. Check for errors and try again.
Hypnotic Chill Daiquiri,
How To Open Gas Tank On 2022 Subaru Outback,
Gary Patterson First Wife,
Iowa Police Jurisdiction Laws,
Pastel Silver Overtone On Brown Hair,
Articles C
