Items in AFP with MESH term: Tomography, X-Ray Computed
ABSTRACT: Uncomplicated seizures and epilepsy are common in infants and children. Family physicians should be aware of certain epilepsy syndromes that occur in children, such as febrile seizures, benign focal epilepsy of childhood, complex partial epilepsy, juvenile myoclonic epilepsy and video game-related epilepsy. Not all uncomplicated childhood seizures require neuroimaging or treatment. Febrile seizures, rolandic seizures and video game-related seizures are childhood epileptic syndromes that are typically not associated with brain structural lesions on computed tomography or magnetic resonance imaging, and are often not treated with anticonvulsant drugs. Juvenile myoclonic epilepsy does not require neuroimaging but does require treatment because of a high rate of recurrent seizures. Complex partial epilepsy often requires both neuroimaging and treatment. Although seizures are diagnosed primarily on clinical grounds, all children with a possible seizure (except febrile seizures) should have an electroencephalogram. Interictal EEGs may be normal. Computed tomography has demonstrated abnormalities in 7 to 19 percent of children with new-onset seizures. The yield of magnetic resonance imaging for specific childhood seizure types is not known, but it is the preferred modality of neuroimaging for many clinical presentations. Most children's seizures treated with anticonvulsants are controlled by the first drug selected. The value of "therapeutic' serum drug levels is questionable in the management of uncomplicated childhood seizures.
ABSTRACT: The treatment of osteosarcoma requires a multidisciplinary approach involving the family physician, orthopedic oncologist, medical oncologist, radiologist and pathologist. Osteosarcoma is a mesenchymally derived, high-grade bone sarcoma. It is the third most common malignancy in children and adolescents. The most frequent sites of origin are the distal femur, proximal tibia and proximal humerus. Patients typically present with pain, swelling, localized enlargement of the extremity and, occasionally, pathologic fracture. Most patients present with localized disease. Radiographs commonly demonstrate a mixed sclerotic and lytic lesion arising in the metaphyseal region of the involved bone. Computed tomography and bone scanning are recommended to detect pulmonary and bone metastases, respectively. Before 1970, osteosarcomas were treated with amputation. Survival was poor: 80 percent of patients died from metastatic disease. With the development of induction and adjuvant chemotherapy protocols, advances in surgical techniques and improvements in radiologic staging studies, 90 to 95 percent of patients with osteosarcoma can now be treated with limb-sparing resection and reconstruction. Long-term survival and cure rates have increased to between 60 and 80 percent in patients with localized disease.
ABSTRACT: Osteoporosis affects nearly 28 million elderly Americans. Its major clinical manifestation is fragility fractures of the spine, hip, and distal radius. Low bone mass is the most important risk factor for a fragility fracture. In 1994, the World Health Organization defined osteoporosis on the basis of a bone mineral density that is 2.5 standard deviations below that in peak young normal persons. Three common imaging modalities used to assess bone strength are dual-energy x-ray absorptiometry, quantitative computed tomography, and calcaneal ultrasonography. The first two modalities measure bone mineral density in both the lumbar spine and peripheral sites. It is thought that calcaneal ultrasonography measures bone architecture and density. Unlike the other studies, ultrasonography currently cannot be used for monitoring skeletal changes over time or evaluating response to therapy.
Acute Respiratory Distress Syndrome - Article
ABSTRACT: Acute respiratory distress syndrome is the clinical manifestation of severe, acute lung injury. It is characterized by the acute onset of diffuse, bilateral pulmonary infiltrates secondary to noncardiogenic pulmonary edema, refractory hypoxia, and decreased lung compliance. Acute respiratory distress syndrome occurs most frequently in the setting of sepsis, aspiration of gastric contents, trauma, or multiple transfusions. Its complex pathophysiology involves an inciting local or systemic event that initiates pulmonary endothelial and epithelial damage and subsequent increased permeability. Tachypnea, hypoxia, and respiratory alkalosis are typical early clinical manifestations, and they are usually followed by the appearance of diffuse pulmonary infiltrates and respiratory failure within 48 hours. Early identification and treatment of the underlying disorder, along with aggressive supportive care, are essential. Experimental therapies, including those using nitric oxide and surfactant, have not been shown to improve mortality in patients with ARDS, but new therapeutic approaches such as low-volume ventilation have been shown to decrease mortality. Many patients who survive ARDS have permanent, mild to moderate impairment of lung function. Quality of life after hospitalization with ARDS may be poorer than that in similar patients without ARDS.
ABSTRACT: Sinusitis is one of the most common diseases treated by primary care physicians. Uncomplicated sinusitis does not require radiologic imagery. However, when symptoms are recurrent or refractory despite adequate treatment, further diagnostic evaluations may be indicated. Plain radiography has a limited role in the management of sinusitis. Although air-fluid levels and complete opacification of a sinus are more specific for sinusitis, they are only seen in 60 percent of cases. Noncontrast coronal computed tomographic (CT) images can define the nasal anatomy much more precisely. Mucosal thickening, polyps, and other sinus abnormalities can be seen in 40 percent of symptomatic adults; however, clinical correlation is needed to avoid overdiagnosis of sinusitis because of nonspecific CT findings. Use of CT is typically reserved for difficult cases or to define anatomy prior to sinus surgery. Magnetic resonance imaging (MRI) cannot define bony anatomy as well as CT. MRI is only used to differentiate soft-tissue structures, such as in cases of suspected fungal infection or neoplasm. Referral will occasionally be needed in unusual or complicated cases. Immunocompromised persons and smokers are at increased risk for serious sinusitis complications.
ABSTRACT: Compression fracture of the vertebral body is common, especially in older adults. Vertebral compression fractures usually are caused by osteoporosis, and range from mild to severe. More severe fractures can cause significant pain, leading to inability to perform activities of daily living, and life-threatening decline in the elderly patient who already has decreased reserves. While the diagnosis can be suspected from history and physical examination, plain roentgenography, as well as occasional computed tomography or magnetic resonance imaging, are often helpful in accurate diagnosis and prognosis. Traditional conservative treatment includes bed rest, pain control, and physical therapy. Interventional procedures such as vertebroplasty can be considered in those patients who do not respond to initial treatment. Family physicians can help patients prevent compression fractures by diagnosing and treating predisposing factors, identifying high-risk patients, and educating patients and the public about measures to prevent falls.
ABSTRACT: A detailed history alone may lead to a specific diagnosis in approximately 70 percent of patients who have wrist pain. Patients who present with spontaneous onset of wrist pain, who have a vague or distant history of trauma, or whose activities consist of repetitive loading could be suffering from a carpal bone nonunion or from avascular necrosis. The hand and wrist can be palpated to localize tenderness to a specific anatomic structure. Special tests can help support specific diagnoses (e.g., Finkelstein's test, the grind test, the lunotriquetral shear test, McMurray's test, the supination lift test, Watson's test). When radiography is indicated, the posterior-anterior and lateral views are essential to evaluate the bony architecture and alignment, the width and symmetry of the joint spaces, and the soft tissues. When the diagnosis remains unclear, or when the clinical course does not improve with conservative measures, further imaging modalities are indicated, including ultrasonography, technetium bone scan, computed tomography, and magnetic resonance imaging. If all studies are negative and clinically significant wrist pain continues, the patient may need to be referred to a specialist for further evaluation, which may include cineroentgenography, diagnostic arthrography, or arthroscopy.
Imaging for Suspected Appendicitis - Article
ABSTRACT: Acute appendicitis is the most common reason for emergency abdominal surgery and must be distinguished from other causes of abdominal pain. Family physicians play a valuable role in the early diagnosis and management of this condition. However, the overall diagnostic accuracy achieved by traditional history, physical examination, and laboratory tests has been approximately 80 percent. The ease and accuracy of diagnosis varies by the patient's sex and age, and is more difficult in women of childbearing age, children, and elderly persons. If th diagnosis of acute appendicitis is clear from the history and physical examination, prompt surgical referral is warranted. In atypical cases, ultrasonography and computed tomography (CT) may help lower the rate of false-negative appendicitis diagnoses, reduce morbidity from perforation, and lower hospital expenses. Ultrasonography is safe and readily available, with accuracy rates between 71 and 97 percent, although it is highly operator dependent and difficult in patients with a large body habitus. While there is controversy regarding the use of contrast media and which CT technique is best, the accuracy rate of CT scanning is between 93 and 98 percent. Disadvantages of CT include radiation exposure, cost, and possible complications from contrast media.
ABSTRACT: Dementia is a common disorder among older persons, and projections indicate that the number of patients with dementia in the United States will continue to grow. Alzheimer's disease and vascular dementia account for the majority of cases of dementia. After a thorough history and physical examination, including a discussion with other family members, a baseline measurement of cognitive function should be obtained. The Mini-Mental State Examination is the most commonly used instrument to document cognitive impairment. Initial laboratory evaluation includes tests for thyroid-stimulating hormone and vitamin B12 levels. Structural neuroimaging with noncontrast computed tomography or magnetic resonance imaging also is recommended. Other testing should be guided by the history and physical examination. Neuropsychologic testing can help determine the extent of cognitive impairment, but it is not recommended on a routine basis. Neuropsychologic testing may be most helpful in situations where screening tests are normal or equivocal, but there remains a high level of concern that the person may be cognitively impaired.
ABSTRACT: Microscopic hematuria, a common finding on routine urinalysis of adults, is clinically significant when three to five red blood cells per high-power field are visible. Etiologies of microscopic hematuria range from incidental causes to life-threatening urinary tract neoplasm. The lack of evidence-based imaging guidelines can complicate the family physician's decision about the best way to proceed. Patients with proteinuria, red cell casts, and elevated serum creatinine levels should be referred promptly to a nephrology subspecialist. Microscopic hematuria with signs of urinary tract infection should resolve with appropriate treatment of the underlying infection. Patients with asymptomatic microscopic hematuria or with hematuria persisting after treatment of urinary tract infection also need to be evaluated. Because upper and lower urinary tract pathologies often coexist, patients should be evaluated using cytology plus intravenous urography, computed tomography, or ultrasonography. When urine cytology results are abnormal, cystoscopy should be performed to complete the investigation.