The cardiac diagnostic unit. A new approach to patient care

The Cardiac Diagnostic Unit at Duke University Hospital brings together multiple diagnostic services for evaluation of patients with cardiovascular disease. This Unit is a combined effort of the departments of Medicine, Radiology, Surgery, Bioengineering, and Computer Sciences. The reasons for the establishment of the Unit are discussed, along with some illustrative case studies.     

Splenic abscess. A new diagnostic and therapeutic approach. Apropos of 7 cases

Anomalies in seven patients with splenic abscess were invariably observed on ultrasound imaging despite absent or misleading clinical symptomatology splenomegaly was detected in only 3 cases. The abscess was multiple in 6 cases with perisplenic extension in 2 patients. Splenectomy was performed in only 2 cases. In one patient, diagnostic and therapeutic fine needle puncture of spleen was performed. Comparison with CT scan imaging is presented with respect to 3 patients. Ultrasound imaging can suggest a diagnosis of intrasplenic abscess and fine needle puncture is not contraindicated.     

FDG-PET: a new diagnostic approach in hip prosthetic replacement

Infection following hip arthroplasties can present a diagnostic challenge. No test is 100 % sensitive and 100 % specific; this prospective study was undertaken to evaluate the utility of FDG-PET imaging for diagnosing infected joint replacements. 24 hip joint replacements were studied prospectively and we have complete diagnoses with clinical signs and symptoms, laboratory test, radiography, joint aspiration, radionuclide imaging including FDG-PET, and histopathologic examination. 11 of 24 prostheses were infected. The sensitivity and specificity of PET for detecting infection associated with prostheses were 64,3 % and 64,7 % respectively, in our hands. FDG imaging is not useful in patients with suspected prosthetic infection like a screening test.     

Tibial hyperostosis: A diagnostic approach

Tibial hyperostosis may be encountered in musculoskeletal imaging, incidentally or during the investigation of a leg pain. Hyperostosis involves the exuberant production of osseous tissue and results in cortical, periosteal and/or endosteal thickening of the bone. As a long bone with thick cortices, the tibia has a significant probability of being affected by ubiquitous bone diseases. As a tubular long bone, the tibia is likely to be involved in extensive infectious conditions such as osteomyelitis. As a bone of the lower limb, the tibia undergoes high stresses and may be affected by decrease in bone strength or repetitive submaximal stress. The tibia is also particularly involved in some bone sclerosing dysplasias and Paget's disease. In this work, we aim at highlighting the main conditions leading to tibial hyperostosis and try to provide key elements to narrow down the several diagnostic possibilities. Osteoid osteomas, fatigue or insufficiency fractures, infectious conditions, vascular lesions, sclerosing bone dysplasias and Paget's disease represent the main challenging diagnoses to discuss.     

A new diagnostic method of spondylodiscitis. Magnetic resonance imaging

Twenty four patients who were hospitalized for a suspicion of spondylodiscitis were prospectively evaluated with magnetic resonance imaging (MRI), radiology and radionuclide studies. Fifteen patients had an infectious spondylodiscitis, four had a vertebral degenerative disease, four had a rheumaticus spondylodiscitis, one had a chemical spondylodiscitis. The microbiological examinations and the clinical development bore the diagnosis out. Seven patients underwent Indium 111 scanning. The results of this scanning were correlated with MRI results. The MRI was performed with a 0.35 T whole body superconducting unit using spin echo technique. All patients were studied in the sagittal plane with two pulse sequences and more often with a surface-coil: TR 500 msec./TE 28 msec. and TR 2,000 msec./TE 60 msec. In all cases of true infectious spondylodiscitis the MRI results finding were characteristics. On the image obtained with the TR 500 msec./TE 28 msec., there was a confluent decreased signal intensity from the vertebral bodies and the intervertebral disk space. On the image obtained with TR 2,000 msec./TE 60 msec. there was an increased signal intensity from the vertebral bodies and the intervertebral disk space. The other spondylodiscitis have given a different MRI imaging, it was a confluent decreased signal intensity from the vertebral bodies and the intervertebral disk space on the twice pulse sequences. different images were obtained during the evolution of the infectious: first we observed a modification of the vertebral signal then the typical image that we described then a normal signal of the vertebral bodies with a pathological signal from the intervertebral disk space at last a degenerative intervertebral disk.(ABSTRACT TRUNCATED AT 250 WORDS)     

A new approach to split resonator design.

Using a novel application of the method of images we show how a plane array of resonant elements can be substituted for the conducting plane in a semicylindrical or split resonator. In an experimental low-pass split resonator-plane array system used as a magnetic resonance imaging receive coil at 0.5 T sensitivity values are shown to be uniform (approximately +/- 3%) across the field of view.     

Sonography of pancreatic carcinoma. Sonomorphology, diagnostic accuracy and tumor staging

Ultrasonography was performed in 125 consecutive patients with clinically suspected carcinoma of the pancreas. The most important diagnostic criteria were reflectivity and echo amplitude, which were locally decreased in 71% (50/70) and increased in 27% (19/70) of the cancers. The echogenicity and reflectivity did not differ in four endocrine active tumors and adenocarcinomas. The diagnostic accuracy was 83% (101/122); in 3 patients ultrasonography failed to provide adequate information. Dilation of the biliary tree was found in 68% (43/50) of the carcinomas and dilation of the Wirsungian duct in 52% (32/58). There was some difficulty in differentiating between pancreatic carcinoma and chronic pancreatitis because the echogenicity is similar for both and inflammatory and neoplastic pancreatic processes are also present in both diseases. Although only 2-3 cm in diameter, 87% (7/8) of the carcinomas were already in the T3 stage. Angiography to evaluate resectability is unnecessary only when vascular encasement, extensive infiltration of peripancreatic fat, or tumor thrombus has been demonstrated sonographically.     

A new approach to RIS/DR interconnection.

The article focuses on a new, standards-based approach for linking modalities to a radiology information system (RIS) in the radiology department. Computers have been used in radiology for quite some time-for the complex processing of algorithms used by CT and MR, for example. The advent of computed radiography (CR) and direct radiography (DR) has helped bring x-ray film into the world of computers. DR uses a technology similar to that in digital cameras to convert the intensity and location of the diagnostic image into digital form. Many radiology departments now store images on disks and read from computer monitors in a reading room. With its high-volume radiology department, the Cleveland Clinic Foundation (CCF) has been a long-time user of one particular RIS system. As the department moved to DR implementation, it required a means to automatically include patient demographic information with the image at the time of study acquisition, so this information would be associated with the image throughout its history. Using an approach developed by several companies in connection with CCF, technologists now use only two interfaces on one computer screen. Further, a technologist can close the study from the DR unit, allowing more time for patient care. The collaborative effort between CCF and the companies involved has resulted in an exciting standards-based approach to linking its RIS and DR systems.     

MR imaging of cervical carcinoma: a practical staging approach.

Cervical carcinoma is the third most common gynecologic malignancy and is typically seen in younger women, often with serious consequences. The International Federation of Gynecology and Obstetrics (FIGO) staging system provides worldwide epidemiologic and treatment response statistics. However, there are significant inaccuracies in the FIGO staging system, and magnetic resonance (MR) imaging, although not included in that system, is now widely accepted as optimal for evaluation of important prognostic factors such as lesion volume and metastatic lymph node involvement that will help determine the treatment strategy. MR imaging examination obviates the use of invasive procedures such as cystoscopy and proctoscopy, especially when there is no evidence of local extension. Brachytherapy and external beam therapy are optimized with MR imaging evaluation of the shape and direction of lesion growth. In general, T2-weighted MR imaging more clearly delineates cervical carcinoma and is preferred for evaluation of the lymph nodes. Dynamic gadolinium-enhanced T1-weighted imaging may help identify smaller tumors, detect or confirm invasion of adjacent organs, and identify fistulous tracts. MR imaging staging, when available, is invaluable for identifying important prognostic factors and optimizing treatment strategies.     

A new diagnostic approach using regional analysis of anterior knee laxity in patients with anterior cruciate ligament deficiency

Purpose  

The first purpose of this study was to analyze the characteristics of the anterior knee laxity in the three regions of different stiffness in the force–displacement curve, which was obtained from a frequently used arthrometer for quantifying knee joint stability in the patients with anterior cruciate ligament (ACL) rupture and the healthy controls. The second purpose was to compare the characteristics from the regional analysis of the anterior knee laxity between the two subject groups in order to explore proper diagnosis criteria.     

Improved diagnostic accuracy in the TNM staging of laryngeal cancer using a new definition of regions based on computed tomography

Neither laryngoscopy nor laryngography can match the accuracy with which computed tomography (CT) can display the full tumor extent or the presence of cartilage invasion. Data obtained from a CT-histologic correlative study have suggested a new definition of regions of the larynx for use with the TNM staging of laryngeal cancer. The arytenoid cartilage, readily identifiable by CT, is used for reference. The regions are as follows: (a) supra-arytenoid, (b) midarytenoid, (c) vocal process, and (d) infra-arytenoid. Tumors with a strong propensity for cartilage invasion can be distinguished from those without this tendency. In addition, tumors with different pathways of lymphatic drainage can be identified.     

Determining diagnostic radiographer staffing requirements: A workload-based approach

IntroductionThe topic of healthcare human resource planning for diagnostic radiographers has received limited research attention to date. This research is concerned with developing a framework that can be used to determine diagnostic radiographer staffing requirements at a unit- or department level (i.e. at the micro-level).MethodsAn inductive approach is applied to formulate requirement specifications that inform the development of the framework. A number of verification and validation activities are performed, including theoretical verification and a case study application.ResultsThe diagnostic radiographer staffing framework consists of seven steps that comprise a workload-based approach to determining the number of full time equivalent diagnostic radiographers that are required for each modality, or group of modalities. Both clinical and non-clinical activities are considered, and guidance is provided on calculating staffing requirements to cover leave allowances. A number of potential approaches to determining activity times are also discussed.ConclusionThe framework represents a holistic approach to determining the required number of diagnostic radiographers at a practice-level, that is designed to remain relevant as technological advances are made in the field of diagnostic radiography.Implications for practiceBy providing a practical guideline, with accompanying examples, the framework is expected to hold value for individuals involved in the management of diagnostic radiography practices. The framework proposes an approach to a topic that affects every radiography practice in operation yet has received limited attention in literature to date.     

A diagnostic approach to lytic lesions of the mandible

Fifty seven patients with histologically proven cyst-like lesions of the mandible are reviewed. The importance of combining radiographic with scintigraphic imaging is stressed. These two imaging modalities are complementary in demonstrating both the biological activity and the extent of the lesion. In osteomyelitis the bone scan, which is more sensitive than the radiograph, is also the method of choice in assessing the result of treatment.     

A multimodal diagnostic approach to inverted papilloma: Proposal of a novel diagnostic flow-chart

PurposeInverted papilloma (IP) is a tumor usually arising from sinonasal cavities, with tendency for recurrence and possible malignant transformation. Along with endoscopy, computed tomography (CT) and magnetic resonance imaging (MRI) play a crucial role in defining preoperative staging, tumor origin, and possible differential diagnosis, with significant repercussions on therapeutic planning. However, at present no consensus has been reached concerning IP diagnostic workup. Aim of this study is to assess CT and MRI sensitivity and specificity in identifying IP imaging hallmarks, evaluating their global diagnostic accuracy in order to define a novel diagnostic flowchart.MethodsWe retrospectively analyzed multimodal imaging of patients with histologically confirmed IP and mimics. Two neuroradiologists in consensus retrospectively rated the presence of typical imaging features of IP, both on CT and MRI scans. Sensitivity, specificity and diagnostic accuracy were assessed for both the techniques. Final results were expressed as ROC curves and relative areas under the curve (AUC).ResultsThe AUC considering CT parameters were 0.42, whereas the AUC considering MRI parameters were 0.54. Combining the 2 techniques and limiting the evaluation to the most distinctive features such as focal hyperostosis and CCP, the AUC was 0.79.ConclusionMRI can provide better tissue characterization and higher diagnostic accuracy in case of suspected IP, whereas CT is more useful in determining bony involvement. Here we propose a possible diagnostic flowchart for IP, based on the assumption that the combination of the imaging techniques allows to optimize the clinical assessment and the subsequent therapeutic planning.     

Role and limits of diagnostic imaging in the staging of lung cancer

A total of 474 histologically proved Lung Cancers (LC) were evaluated by Conventional Radiology (CR) and Computed Tomography (CT) in order to assess the role of these two diagnostic modalities in the staging of LC. In 196/474 LC it was possible also to refer, for the evaluation of the diagnostic reliability, to the surgical control. The CR features of LC both at stage III (13% of the global series) and at stage I-peripheral T1 (16% of the global series) presented very high positive and negative predictive values (90% and 95%, retrospectively); in these cases it was considered useless to perform CT. The CT grading showed a high negative predictive value in excluding stage III caused respectively by grade T3 (91.5%) and grade N2 (93.5%). As to the staging, the CT assessment of the stage I and II showed a high predictive value (91.5%). On the other hand, the CT assessment of stage III presented an unsatisfactory predictive value (71%), due to the low predictive value in grade T3 (71.5%), poor in grade N2 (57.5%). The increase of the value threshold mediastinal adenopathies from 1 to 2 cm, leads to a great improvement of this predictive value (92%). The CT reliability was matched with the two different surgical "philosophies" (non aggressive or aggressive); surgery was excluded or performed according to the presence of omo-lateral mediastinal adenopathy. A correct advice to perform surgery was achieved in 33.5% (non aggressive "philosophy") and 43.8% (aggressive "philosophy") of cases; surgery was correctly excluded respectively in 49.6% and 45.9%. The resort to mediastinoscopy was advised in 7.8% and 1.3% of the cases respectively. In both "philosophies" the error of under-staging was lower (2.5%), than that of over-staging (6.6%).