Items in AFP with MESH term: Tomography, X-Ray Computed
Diabetic Ketoacidosis - Article
ABSTRACT: A diagnosis of diabetic ketoacidosis requires the patient's plasma glucose concentration to be above 250 mg per dL (although it usually is much higher), the pH level to be less than 7.30, and the bicarbonate level to be 18 mEq per L or less. Beta-hydroxybutyrate is a better measurement of the degree of ketosis than serum ketones. Intravenous insulin and fluid replacement are the mainstays of therapy, with careful monitoring of potassium levels. Phosphorous and magnesium also may need to be replaced. Bicarbonate therapy rarely is needed. Infection, insulin omission, and other problems that may have precipitated ketoacidosis should be treated. Myocardial infarction is a precipitating cause of diabetic ketoacidosis that is especially important to look for in older patients with diabetes. Cerebral edema is a major complication that occurs primarily in children. Education to prevent recurrence should be offered to all patients, including how to manage sick days and when to call a physician.
Abdominal Aortic Aneurysm - Article
ABSTRACT: Most abdominal aortic aneurysms (AAAs) are asymptomatic, not detectable on physical examination, and silent until discovered during radiologic testing for other reasons. Tobacco use, hypertension, a family history of AAA, and male sex are clinical risk factors for the development of an aneurysm. Ultrasound, the preferred method of screening, is cost-effective in high-risk patients. Repair is indicated when the aneurysm becomes greater than 5.5 cm in diameter or grows more than 0.6 to 0.8 cm per year. Asymptomatic patients with an AAA should be medically optimized before repair, including institution of beta blockade. Symptomatic aneurysms present with back, abdominal, buttock, groin, testicular, or leg pain and require urgent surgical attention. Rupture of an AAA involves complete loss of aortic wall integrity and is a surgical emergency requiring immediate repair. The mortality rate approaches 90 percent if rupture occurs outside the hospital. Although open surgical repair has been performed safely, an endovascular approach is used in select patients if the aortic and iliac anatomy are amenable. Two large randomized controlled trials did not find any improvement in mortality rate or morbidity with this approach compared with conventional open surgical repair.
ABSTRACT: Cirrhosis and chronic liver failure are leading causes of morbidity and mortality in the United States, with the majority of preventable cases attributed to excessive alcohol consumption, viral hepatitis, or nonalcoholic fatty liver disease. Cirrhosis often is an indolent disease; most patients remain asymptomatic until the occurrence of decompensation, characterized by ascites, spontaneous bacterial peritonitis, hepatic encephalopathy, or variceal bleeding from portal hypertension. Physical examination of patients with cirrhosis may reveal a variety of findings that necessitate a hepatic- or gastrointestinal-based work-up to determine the etiology. Some patients already may have had laboratory or radiographic tests that incidentally uncovered signs of cirrhosis and its comorbidities. No serologic or radiographic test can accurately diagnose cirrhosis. A significant correlation has been demonstrated between persistently elevated liver function tests and biopsy-proven underlying hepatic disease; thus, a more targeted serologic work-up is indicated in patients whose liver function test results are persistently abnormal. Unnecessary medications and surgical procedures should be avoided in patients with cirrhosis. Referral for liver biopsy should be considered only after a thorough, non-invasive serologic and radiographic evaluation has failed to confirm a diagnosis of cirrhosis; the benefit of biopsy outweighs the risk; and it is postulated that biopsy will have a favorable impact on the treatment of chronic liver disease.
ABSTRACT: The first step in the evaluation of patients with pleural effusion is to determine whether the effusion is a transudate or an exudate. An exudative effusion is diagnosed if the patient meets Light's criteria. The serum to pleural fluid protein or albumin gradients may help better categorize the occasional transudate misidentified as an exudate by these criteria. If the patient has a transudative effusion, therapy should be directed toward the underlying heart failure or cirrhosis. If the patient has an exudative effusion, attempts should be made to define the etiology. Pneumonia, cancer, tuberculosis, and pulmonary embolism account for most exudative effusions. Many pleural fluid tests are useful in the differential diagnosis of exudative effusions. Other tests helpful for diagnosis include helical computed tomography and thoracoscopy.
Noninvasive Cardiac Imaging - Article
ABSTRACT: Noninvasive cardiac imaging can be used for the diagnostic and prognostic assessment of patients with suspected or known coronary artery disease. It is central to the treatment of patients with myocardial infarction, coronary artery disease, or acute coronary syndromes with or without angina. Radionuclide cardiac imaging; echocardiography; and, increasingly, cardiac computed tomography and cardiac magnetic resonance imaging techniques play an important role in the diagnosis of coronary artery disease, which is the leading cause of mortality in adults in the United States. Contemporary imaging techniques, with either stress nuclear myocardial perfusion imaging or stress echocardiography, provide a high sensitivity and specificity in the detection and risk assessment of coronary artery disease, and have incremental value over exercise electrocardiography and clinical variables. They also are recommended for patients at intermediate to high pretest likelihood of coronary artery disease based on symptoms and risk factors. Cardiac magnetic resonance imaging and cardiac computed tomography are newly emerging modalities in the evaluation of patients with coronary artery disease. Cardiac magnetic resonance imaging is useful in the assessment of myocardial perfusion and viability, as well as function. It also is considered a first-line tool for the diagnosis of arrhythmogenic right ventricular dysplasia. Cardiac computed tomography detects and quantifies coronary calcium and evaluates the lumen and wall of the coronary artery. It is a clinical tool for the detection of subclinical coronary artery disease in select asymptomatic patients with an intermediate Framingham 10-year risk estimate of 10 to 20 percent. In addition, cardiac computed tomography is evolving as a noninvasive tool for the detection and quantification of coronary artery stenosis. Although guidelines can help with treating patients, treatment ultimately should be tailored to each person based on clinical judgment of the a priori risk of a cardiac event, symptoms, and the cardiac risk profile.
ABSTRACT: The American College of Radiology has developed appropriateness criteria for a number of clinical conditions and procedures. Criteria are available on imaging tests used in the evaluation of acute chest pain--suspected myocardial ischemia. Imaging tests for a suspected cardiac etiology include transthoracic echocardiography, transesophageal echocardiography, radionuclide perfusion imaging, radionuclide ventriculography, radionuclide infarct avid imaging, and positron emission tomography. If the cardiac ischemic work-up is negative or indeterminate, applicable tests include chest radiography; conventional, multidetector, and electron beam computed tomography; and magnetic resonance imaging. A summary of the criteria, with the advantages and limitations of each test, is presented in this article.
ABSTRACT: Shoulder pain is defined as chronic when it has been present for longer than six months. Common conditions that can result in chronic shoulder pain include rotator cuff disorders, adhesive capsulitis, shoulder instability, and shoulder arthritis. Rotator cuff disorders include tendinopathy, partial tears, and complete tears. A clinical decision rule that is helpful in the diagnosis of rotator cuff tears includes pain with overhead activity, weakness on empty can and external rotation tests, and a positive impingement sign. Adhesive capsulitis can be associated with diabetes and thyroid disorders. Clinical presentation includes diffuse shoulder pain with restricted passive range of motion on examination. Acromioclavicular osteoarthritis presents with superior shoulder pain, acromioclavicular joint tenderness, and a painful cross-body adduction test. In patients who are older than 50 years, glenohumeral osteoarthritis usually presents as gradual pain and loss of motion. In patients younger than 40 years, glenohumeral instability generally presents with a history of dislocation or subluxation events. Positive apprehension and relocation are consistent with the diagnosis. Imaging studies, indicated when diagnosis remains unclear or management would be altered, include plain radiographs, magnetic resonance imaging, ultrasonography, and computed tomography scans. Plain radiographs may help diagnose massive rotator cuff tears, shoulder instability, and shoulder arthritis. Magnetic resonance imaging and ultrasonography are preferred for rotator cuff disorders. For shoulder instability, magnetic resonance imaging arthrogram is preferred over magnetic resonance imaging.
Chronic Pancreatitis - Article
ABSTRACT: Chronic pancreatitis is the progressive and permanent destruction of the pancreas resulting in exocrine and endocrine insufficiency and, often, chronic disabling pain. The etiology is multifactorial. Alcoholism plays a significant role in adults, whereas genetic and structural defects predominate in children. The average age at diagnosis is 35 to 55 years. Morbidity and mortality are secondary to chronic pain and complications (e.g., diabetes, pancreatic cancer). Contrast-enhanced computed tomography is the radiographic test of choice for diagnosis, with ductal calcifications being pathognomonic. Newer modalities, such as endoscopic ultrasonography and magnetic resonance cholangiopancreatography, provide diagnostic results similar to those of endoscopic retrograde cholangiopancreatography. Management begins with lifestyle modifications (e.g., cessation of alcohol and tobacco use) and dietary changes followed by analgesics and pancreatic enzyme supplementation. Before proceeding with endoscopic or surgical interventions, physicians and patients should weigh the risks and benefits of each procedure. Therapeutic endoscopy is indicated for symptomatic or complicated pseudocyst, biliary obstruction, and decompression of pancreatic duct. Surgical procedures include decompression for large duct disease (pancreatic duct dilatation of 7 mm or more) and resection for small duct disease. Lateral pancreaticojejunostomy is the most commonly performed surgery in patients with large duct disease. Pancreatoduodenectomy is indicated for the treatment of chronic pancreatitis with pancreatic head enlargement. Patients with chronic pancreatitis are at increased risk of pancreatic neoplasm; regular surveillance is sometimes advocated, but formal guidelines and evidence of clinical benefit are lacking.
Acute Pericarditis - Article
ABSTRACT: Although acute pericarditis is most often associated with viral infection, it may also be caused by many diseases, drugs, invasive cardiothoracic procedures, and chest trauma. Diagnosing acute pericarditis is often a process of exclusion. A history of abrupt-onset chest pain, the presence of a pericardial friction rub, and changes on electrocardiography suggest acute pericarditis, as do PR-segment depression and upwardly concave ST-segment elevation. Although highly specific for pericarditis, the pericardial friction rub is often absent or transient. Auscultation during end expiration with the patient sitting up and leaning forward increases the likelihood of observing this physical finding. Echocardiography is recommended for most patients to confirm the diagnosis and to exclude tamponade. Outpatient management of select patients with acute pericarditis is an option. Complications may include pericardial effusion with tamponade, recurrence, and chronic constrictive pericarditis. Use of colchicine as an adjunct to conventional nonsteroidal anti-inflammatory drug therapy for acute viral pericarditis may hasten symptom resolution and reduce recurrences.
Functional Endoscopic Sinus Surgery - Article
ABSTRACT: Functional endoscopic sinus surgery is a minimally invasive technique used to restore sinus ventilation and normal function. The most suitable candidates for this procedure have recurrent acute or chronic infective sinusitis, and an improvement in symptoms of up to 90 percent may be expected following the procedure. Fiberoptic telescopes are used for diagnosis and during the procedure, and computed tomography is used to assess the anatomy and identify diseased areas. Functional endoscopic sinus surgery should be reserved for use in patients in whom medical treatment has failed. The procedure can be performed under general or local anesthesia on an outpatient basis, and patients usually experience minimal discomfort. The complication rate for this procedure is lower than that for conventional sinus energy.