Lumbar herniated disks

Patients with low back and leg pain require careful evaluation and it is essential that there is correlation between the symptoms and signs of sciatica and the imaging demonstration of nerve root compression or displacement by a disk herniation before invasive therapy is undertaken. The natural history of herniations of the nucleus pulposus is complex and the relationship between the appearances on imaging and low back and radicular pain still has to be completely resolved. Considerable experimental work has been undertaken on the relationship between nerve compression, inflammation, and pain and recent studies on cytokines may lead to more precise pharmacologic therapies. The prime value of MR imaging may be in monitoring disk and nerve root changes in longitudinal studies of patients randomized to different therapeutic programs.     

ACR Appropriateness Criteria® Myelopathy

Myelopathy is a problem that requires imaging to distinguish among numerous specifically treatable causes. The first priority is to determine mechanical stability after trauma. Next, it is crucial to distinguish intrinsic disease from extrinsic compression-for example, by epidural abscess. Osteophytes or disc extrusions and metastatic compression are the most common causes of extrinsic lesions. Imaging approaches rely on clinical features such as pain, fever, trauma, and pattern of progression. CT is preferred initially in acute trauma and MRI in all other circumstances. Contrast-enhanced MRI is added when tumor or infection is suspected or with slow or stepwise progression, especially when pain is not prominent. Vascular imaging is used when arteriovenous malformation, fistula, or occlusive disease is suspected. Because the treatment of myelopathy is often complex, treatment planning may require more than one imaging study or sequential examination to assess interval change. The ACR Appropriateness Criteria(?) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment.     

Cardiac imaging in the evaluation of patients presenting to the emergency department with chest pain

Conclusions  Despite the utility and benefits that each imaging modality has to offer, it is easy to see why there is still no perfect choice for a noninvasive cardiac imaging modality to assist in the management of chest pain patients. All of the current imaging techniques have their own significant strengths and weaknesses when compared with other modalities. SPECT and echocardiography are wellestablished technologies that can directly assess the presence of myocardial ischemia and its functional consequence on RF; newer and more expensive techniques such as MDCT and CMR can directly assess coronary anatomy and have just started to be evaluated in the acute chest pain setting. There are no studies that directly compare these technologies, and more data are clearly needed before the question of whether anatomic imaging versus perfusion/function imaging is the better approach can be answered. Other comparisons such as relative safety, availability, logistics, and cost-effectiveness between the various technologies are also lacking. Of all of the imaging modalities discussed, MCE is the only portable technology. The images do not require expensive software or other technology for offline processing before interpretation, and any trained cardiologist can read the study at the bedside or, potentially, over the Internet, providing near-instantaneous results in the acute cardiac setting, where time is of the essence. MCE is also relatively cheap compared with other technologies, a potential advantage for payors but not necessarily for payees. How reimbursement rates and fee structures eventually affect clinical practice is also unknown. Despite these and other questions that need to be answered before any one technique will be used exclusively, the future of noninvasive cardiac imaging remains an exciting and ever-changing field. The adaptation of any one of these techniques into its proper role in the ED Journal of Nuclear Cardiology Wyrick and Wei 753 Volume 13, Number 6;749-55 Cardiac imaging in patients with chest pain will take considerably more time and effort in terms of research, money, and time-tested clinical experience.     

CT for evaluation of acute pericardial emergencies in the ED

Acute pericardial emergencies may present with acute chest pain. Although complete diagnosis and physiological effects of acute pericardial disease may require a combination of different imaging, CT plays a critical role in identifying the cause of chest pain in the ED. Many of these pericardial diseases can be fatal unless emergent treatment is obtained. The presentation can often be non-specific and symptoms can be overlapping with other diseases originating in the thorax or abdomen. Optimizing the CT scan is imperative when acute pericardial disease is suspected from clinical examination or preliminary imaging. The interpreting radiologist needs to be aware of the different entities which represent acute pericardial emergencies requiring urgent therapeutic intervention. Time is the essence, the clock is ticking, and every minute counts!     

Low back pain in the aging athlete

Low back pain has an incidence between 1% and 30% in athletes. The natural history of low back pain is such that greater than 90% will improve without medical attention. Our treatment algorithm begins by ruling out nonspinal related causes of low back pain including neoplasm, infection, and serious medical conditions. Next cauda equina compression is differentiated from clinical entities that can be treated on an elective basis. Low back strain, herniated nucleus pulposis, spinal stenosis, and degenerative disease are each discussed with an emphasis on imaging studies finding a correlation between history, physical, and the neurodiagnostic testing. Athletes over the age of 60 who require back surgery should understand that they would most likely not return to their previous level of activity. Recent work has focused on rehabilitative principles such as core stabilization and their role in the prevention and treatment of athletes with lumbar disorders.     

Computed tomography versus intravenous urography in diagnosis of acute flank pain from urolithiasis: a randomized study comparing imaging costs and radiation dose

The equivalent sensitivity of non-contrast computed tomography (NCCT) and intravenous urography (IVU) in the diagnosis of suspected ureteric colic has been established. Approximately 50% of patients with suspected ureteric colic do not have a nephro-urological cause for pain. Because many such patients require further imaging studies, NCCT may obviate the need for these studies and, in so doing, be more cost effective and involve less overall radiation exposure. The present study compares the total imaging cost and radiation dose of NCCT versus IVU in the diagnosis of acute flank pain. Two hundred and twenty-four patients (157 men; mean age 45 years; age range 19-79 years) with suspected renal colic were randomized either to NCCT or IVU. The number of additional diagnostic imaging studies, cost (IVU A$136; CTU A$173), radiation exposure and imaging times were compared. Of 119 (53%) patients with renal obstruction, 105 had no nephro-urological causes of pain. For 21 (20%) of these patients an alternative diagnosis was made at the initial imaging, 10 of which were significant. Of 118 IVU patients, 28 (24%) required 32 additional imaging tests to reach a diagnosis, whereas seven of 106 (6%) NCCT patients required seven additional imaging studies. The average total diagnostic imaging cost for the NCCT group was A$181.94 and A$175.46 for the IVU group (P < 0.43). Mean radiation dose to diagnosis was 5.00 mSv (NCCT) versus 3.50 mSv (IVU) (P < 0.001). Mean imaging time was 30 min (NCCT) versus 75 min (IVU) (P < 0.001). Diagnostic imaging costs were remarkably similar. Although NCCT involves a higher radiation dose than IVU, its advantages of faster diagnosis, the avoidance of additional diagnostic imaging tests and its ability to diagnose other causes makes it the study of choice for acute flank pain at Christchurch Hospital.     

Imaging of the acute scrotum

The scrotum is a superficial structure and clinical examination is frequently not enough for making a specific diagnosis. In acute scrotal pain US can confirm the presumptive clinical diagnosis and provide additional relevant information. In testicular torsion, color-Doppler imaging has a central role since it has become possible to identify it at early stage by showing absence of perfusion in the affected testis before any gray-scale abnormality. Scintigraphy remains a satisfactory alternative in evaluating testicular torsion and should be used when color Doppler is inadequate, raising doubts about the suspected torsion. Diagnosis of torsion of testicular appendages is particularly difficult. Ischemic infarction shows a characteristic pattern at gray-scale and color-Doppler imaging, whereas hemorrhagic ischemia may require MRI. Inflammatory diseases of the scrotum can be easily investigated by echo color Doppler and conventional radiography, and CT can be particularly useful in the detection of gas bubbles. In scrotal trauma, scrotal hematoma, hematocele, intratesticular hematoma, and testicular rupture can be identified using gray-scale US with very good reliability. Magnetic resonance imaging is indicated when a small tear of tunica albuginea is suspected but not visualized on US. Received: 3 May 2000/Accepted: 8 June 2000     

Role of MR imaging in chronic wrist pain

Magnetic resonance (MR) imaging for chronic wrist pain is challenging. Correct assessment of the triangular fibrocartilage, hyaline cartilage, ligaments, and tendons has become mandatory for comprehensive decision making in wrist surgery. The MR technique, potential and limits of MR imaging in patients with chronic wrist pain will be discussed. MR arthrography with injection of gadolinium-containing contrast material into the distal radioulnar joint is suggested for evaluation of the triangular fibrocartilage. The clinically meaningful ulnar-sided peripheral tears are otherwise hard to diagnose. The diagnostic performance of MR imaging for interosseous ligament tears varies considerably. The sensitivity for scapholunate ligament tears is consistently better than for lunotriquetral ligament tears. Gadolinium-enhanced MR imaging is considered to be the best technique for detecting established avascularity of bone, but the assessment of the MR results remains challenging. Most cases of ulnar impaction syndrome have characteristic focal signal intensity changes in the ulnar aspect of the lunate. Avascular necrosis of the lunate (Kienböck’s disease) is characterized by signal changes starting in the proximal radial aspect of the lunate. MR imaging is extremely sensitive for occult fractures. Questions arise if occult posttraumatic bone lesions seen on MR images only necessarily require the same treatment as fractures evident on plain films or computed tomography (CT) images. MR imaging and ultrasound are equally effective for detecting occult carpal ganglia. Carpe bossu (carpal boss) is a bony protuberance of a carpometacarpal joint II and III which may be associated with pain.     

Multimodal study of pelvic splenosis: a rare cause of abdominal pain

We present a rare case of pelvic splenosis, in a 46-year-old man, with a previous history of partial splenectomy, complaining of nonspecific pain in the lower abdominal quadrants. Splenosis is a benign acquired condition, defined as a heterotopic autotransplantation of splenic tissue in other compartments of the body, caused by rupture of the splenic capsule following trauma or splenectomy. Splenosis is often asymptomatic and incidentally found and does not require treatment. Surgery is indicated only in patients presenting with symptoms or complications. In our case, the multimodal imaging study (ultrasound, MRI, CT, and scintigraphy) allowed a correct differential diagnosis without resorting to invasive procedures, susceptible to complications     

Imaging Appropriateness for Neck Pain

Imaging of neck pain contributes to a significant proportion of health care costs and is expected to increase with current practices that heavily use radiologic studies as a diagnostic tool. Though consensus guidelines are available to assist physicians in selection of appropriate imaging examinations for neck pain, it is unclear if current ordering practices reflect their use and understanding. To investigate this, we analyzed the number and types of imaging examinations performed for neck pain at a university medical center over the past year. Current trends at our institution suggest that clinicians use consensus imaging guidelines, but there is still controversy in the cervical spine for when not to image. To promote appropriate imaging utilization, we developed an algorithm to guide imaging of neck pain, based upon clinical presentation, referral patterns for neck pain, and a review of the literature.     

核素骨显像在儿科中的应用

放射性核素骨显像是诊断骨和软组织感染的选择性检查方法,不但有助于隐匿性骨折(X射线诊断阴性)的诊断,在评定小儿可疑非意外损伤方面起重要的补充作用,还可为无法解释的小儿骨痛或跛行提供诸如外伤、肿瘤、或炎症性病变的诊断依据。小儿核素骨显像要求精确的操作才能获得较清晰的诊断图像,常规全身骨显像、缩放比例、附加视图及单光子发射型计算机体层摄影术的使用等都是小儿检查的常规内容,联合CT的融合图像更进一步提高诊断的灵敏度、可信度和精确度。新的放射性药物如Na18F可能在不断更新变化的儿科骨显像技术中起重要作用。     

ACR Appropriateness Criteria Low Back Pain

Most patients presenting with uncomplicated acute low back pain (LBP) and/or radiculopathy do not require imaging. 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 serious underlying conditions, such as cauda equina syndrome, malignancy, fracture, and infection. Many imaging modalities are available to clinicians and radiologists for evaluating LBP. Application of these modalities depends largely on the working diagnosis, the urgency of the clinical problem, and comorbidities of the patient. When there is concern for fracture of the lumbar spine, multidetector CT is recommended. Those deemed to be interventional candidates, with LBP lasting for > 6 weeks having completed conservative management with persistent radiculopathic symptoms, may seek MRI. Patients with severe or progressive neurologic deficit on presentation and red flags should be evaluated with MRI.The ACR 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 (the RAND/UCLA Appropriateness Method and the Grading of Recommendations Assessment, Development, and Evaluation) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.     

Return to play after lumbar spine conditions and surgeries

Low back pain in athletes can result from a wide variety of conditions. A detailed history and physical examination supplemented by appropriate imaging studies can lead to an accurate diagnosis. The majority of cases will be self-limiting and resolve within 6 weeks regardless of treatment, but it is important to be able to identify conditions that require specific treatment. The decision of when an athlete can return to active competition is determined by the specific condition, associated symptoms, and treatment provided. Most athletes can return to full unrestricted play after sufficient resolution of pain and restoration of range of motion. Athletes undergoing spinal fusion are typically restricted from full-contact sports.     

Radionuclide imaging in the assessment of lung injury

Nuclear medicine imaging techniques are being more widely applied to study a variety of lung injuries. Ventilation and perfusion imaging is often superior to other roentgenographic techniques for establishing the diagnosis and demonstrating the extent of such injuries. At several large burn centers, the Xe-133 washout technique has become the cornerstone for diagnosing early inhalation injury. The overall accuracy of this procedure is 92%. Regional decreases in ventilation and perfusion can reliably localize aspirated radiolucent foreign bodies. Disproportionate perfusion changes are often the earliest indicator of radiation pneumonitis and other forms of vascular injury. Other types of injury, such as gastropulmonary aspiration, blunt trauma, and near-drowning, require further evaluation before the ultimate role of nuclear imaging is defined. An imaging technique to assess capillary permeability in the adult respiratory distress syndrome would be of great clinical benefits.     

Patellar tendons with normal imaging and pain: change in imaging and pain status over a volleyball season.

OBJECTIVE: Patellar tendon injury commonly presents as abnormal imaging with pain or abnormal imaging without pain. Normal imaging with pain has also been reported clinically, but little is known about the behavior of these tendons over time. This study investigated the behavior of tendons with normal imaging and pain over a volleyball season. DESIGN: Prospective study. SETTING: Institutional. PARTICIPANTS: One hundred and one male and female volleyball players. MAIN OUTCOME MEASUREMENTS: At the beginning and end of the season ultrasound determined imaging status and the single leg decline squat test determined pain. The imaging and pain status at follow-up of tendons with normal imaging and pain at baseline was reported and contrasted to the imaging and pain status of the other patellar tendon injuries. RESULTS: Tendons with normal imaging and pain [relative risk (RR) 15.1], abnormal imaging without pain (RR 14.6), and abnormal imaging with pain (RR 51.5) had a greater risk of having abnormal imaging with pain at the end of the season when compared with normal tendons (P < 0.01). Among tendons with normal imaging and pain at baseline, 27% had abnormal imaging without pain and 21% contained abnormal imaging with pain at the end of the season. CONCLUSIONS: Patellar tendons with normal imaging and pain at the beginning of a volleyball season are equally as likely to have abnormal imaging and pain at the end of the season as tendons with abnormal imaging without pain. Normal imaging with pain may represent a clinically relevant patellar tendon injury.     

Lumbar degenerative disk disease

The sequelae of disk degeneration are among the leading causes of functional incapacity in both sexes and are a common source of chronic disability in the working years. Disk degeneration involves structural disruption and cell-mediated changes in composition. Mechanical, traumatic, nutritional, and genetic factors all may play a role in the cascade of disk degeneration, albeit to variable degree in different individuals. The presence of degenerative change is by no means an indicator of symptoms, and there is a very high prevalence in asymptomatic individuals. The etiology of pain as the symptom of degenerative disease is complex and appears to be a combination of mechanical deformation and the presence of inflammatory mediators. The role of imaging is to provide accurate morphologic information and influence therapeutic decision making. A necessary component, which connects these two purposes, is accurate natural history data. Understanding the relationship of etiologic factors, the morphologic alterations, which can be characterized with imaging, and the mechanisms of pain production and their interactions in the production of symptoms will require more accurate and reproducible stratification of patient cohorts.     

Imaging of posterior element axial pain generators: facet joints, pedicles, spinous processes, sacroiliac joints, and transitional segments

The role of the posterior elements in generating axial back and neck pain is well established; the imaging detection of posterior element pain generators remains problematic. Morphologic imaging findings have proved to be nonspecific and are frequently present in asymptomatic patients. Edema, inflammation, and hypervascularity are more specific for sites of pain generation, but are often overlooked by imagers if physiologic imaging techniques such as fat-suppressed T2 or contrast-enhanced T1-weighted magnetic resonance imaging, radionuclide bone scanning with single-photon emission computed tomography (CT), or (18)F-fluorodeoxyglucose positron emission tomography combined with CT are not used.     

Reimbursement for chest-pain CT: estimates based on current imaging strategies

The purpose of this study was to estimate reimbursement for chest pain CT, assuming no cost increase for current emergent chest pain imaging. Using reported imaging test characteristics, prevalence and risk of coronary heart disease, and Medicare reimbursement schedules, 10,000 simulated patients were evaluated with three chest pain imaging algorithms. The main difference among the algorithms was the initial imaging tool: stress echocardiography, single photon emission computed tomography (SPECT) and chest pain CT. Outcome analysis included deaths, intra- and extra-hospital myocardial infraction, number of tests performed, time utilization, and the cost per patient. The chest pain CT algorithm was assessed with its reimbursement as an unknown to determine a maximum reimbursement that would not increase overall healthcare costs. Stress echocardiography costs $856.5 per patient with 8.4 observation hours and 646 (27%) negative catheterizations. When SPECT replaces stress echocardiography, the cost increases to $1,413.7 with average observation of 9.05 hours and 1,060 (36%) negative catheterizations. Chest pain CT minimizes observation (by 8.4 and 9.1 compared to echocardiography and SPECT, respectively); negative catheterizations drop to 266 (12%). Solving for chest pain CT reimbursement as an unkown yields $433.1 and $990.3 when compared to echocardiography and SPECT, respectively. Under the assumption that new technology should not increase overall imaging costs, reimbursement for chest pain CT is compatible with current reimbursement for pulmonary embolism and aortic dissection CTA. Reimbursements must be weighed against the complexity and patient benefits of the examination.     

Myocardial perfusion imaging versus biochemical markers in acute coronary syndromes

The assessment and appropriate clinical management of patients with acute chest pain and non-diagnostic electrocardiograms remain a continuing clinical problem. Accordingly, there is considerable interest in evaluating new strategies to improve early diagnostic accuracy in patients with possible acute myocardial ischaemia. Cardiac troponins (T and I) and acute rest myocardial perfusion imaging have similar sensitivities for detecting acute myocardial infarction. Whereas cardiac markers require 6-12 h to become positive, acute rest myocardial perfusion imaging immediately reflects the status of regional myocardial blood flow at the time of radiopharmaceutical injection. The measurement of cardiac troponins is particularly useful in the diagnosis and estimation of the degree of myocardial injury in those patients with a high likelihood of coronary artery disease and myocardial necrosis and for prognostication of adverse cardiac events in those patients with unstable angina. In contrast, the most appropriate use of acute rest myocardial perfusion imaging is in the setting of patients with acute ischaemic symptoms, non-diagnostic electrocardiogram and a low likelihood of myocardial necrosis, in which early imaging will assist in effective triage decisions.     

Clinical MR imaging of degenerative spinal disease: pulse sequences, gradient-echo techniques, and contrast agents.

DEGENERATION OF THE INTERVERTEBRAL disk is a ubiquitous process, seen at autopsy in 97% of adults by age 49 years (1). Low back pain is the most expensive health care problem in patients 20–50 years old, with $14 billion spent yearly on treatment and compensation (2). The greatest costs connected with low back pain occur in patients who have pain longer than 3 months and in those with recurrent pain episodes (3). Approximately 5.2 million people are disabled by back pain (3–5). These statistics indicate that the accurate diagnosis of back pain disease is obviously of great importance. In the diagnosis of disk degeneration and its sequelae, magnetic resonance (MR) imaging has become a key ingredient. The utility of conventional two-dimensional spin-echo MR imaging of the spine has been firmly established for extradural disease (6–8). Gradient-echo techniques have more recently been used to enhance the cerebrospinal fluid (CSF)-extradural interface in the evaluation of degenerative disease (9–13). Some of the new imaging findings and concepts regarding the use of contrast material and three-dimensional techniques in the evaluation of degenerative disease of the spine are reviewed.