Biomedical subjects
Publications and source records attributed to F Kainberger.
The need of clinical sciences to measure therapy effects on chronic illness led to development, evaluation, and publication of several radiological methods to monitor disease progression of rheumatic diseases. This review article explains the basics and background of scoring and measurement. The radiologist thus learns to report more compactly and to communicate the results more specifically.
Computer assisted diagnosis (CAD) schemes are currently used in the field of musculoskeletal diseases to quantitatively assess vertebral fractures, joint space narrowing, andr erosion. Most systems work semi-automatically, i.e. they are operator dependent in the selection of anatomical landmarks. Fully automatic programs are currently under development. Some CAD products have already been successfully used in clinical trials.
PURPOSE: The purpose of this study was to define objective and reproducible standards for the quality of CT images as a function of radiation doses and therapeutic validity. MATERIALS AND METHODS: CT images of the paranasal sinuses of 145 patients (77 female, 68 male; 5-83 years old; mean age, 39.9 years) were classified both subjectively (with a view toward their validity for the planning of functional endoscopic sinus surgery, FESS) and objectively by defining the pixel noise (the standard deviation, STD, of the CT number) in a homogeneous region of interest (ROI), centered on the M. masseter and on the frontal lobe. These measurements were then compared to measurements obtained from scan images of a water-filled Perspex phantom. RESULTS: The pixel noise measured in the phantom images was nearly identical to the respective values on the M. masseter on the patient images. The use of an edge-enhancing reconstruction algorithm and low-dose protocols, with a pixel noise amounting to 70-90 Hounsfield Units (HU), are indicated for children, chronic sinusitis, and septum deviation, while standard protocols, with a pixel noise of 50-70 HU, are recommended for the preoperative planning and postoperative control of FESS. The pixel noise for high-dose protocols is less than 50 HU; nonetheless, such protocols should generally be avoided. CONCLUSION: The pixel noise measured in a water-filled Perspex phantom is indicative of the clinical potential and image quality of paranasal sinus CT scans. Alternatively, the M. masseter can be chosen as an ROI to measure the pixel noise in order to obtain a rough estimate of the image quality or radiation dose class.
PURPOSE: To evaluate the role of projectional radiography in the detection of primary and potentially malignant bone neoplasms. MATERIALS AND METHODS: We retrospectively reviewed the images and medical records of 80 patients (42 male, 38 female; range: 6 to 73 years; mean: 33 years) with pathologically proven primary or indeterminate bone tumors. RESULTS: The most common symptom was local pain (84 %). In 69 of 80 patients (86 %), projectional radiography was the first imaging modality, which correctly identified the malignant character of the bone lesion in 60 of these 69 patients (87 %). In 2 patients, bone neoplasms were overlooked due to diagnostically inadequte image quality. The false-diagnosis rate was not significantly different between board-certified radiologists working in hospitals and radiologists in outpatient facilities (p > 0.05). Bone tumors predominantly affecting adults, such as chondrosarcomas, needed a longer time for the diagnosis than bone tumors mainly found in childhood, such as osteosarcomas. The median age of patients with delayed imaging work-up because of attempted conservative therapy (45 years +/- 20 years) was significant higher than the median age of patients with immediate radiographic work-up (27 years +/- 16 years). CONCLUSION: Projectional radiography is the most common initial imaging method for bone pain and continues to play an important role to reduce the time gap between first onset of symptoms and definitive treatment. In unremitting focal bone pain, bone neoplasms should be taken into consideration not only in children but also in patients beyond adolescence.
BACKGROUND: Low dose radiotherapy is commonly used for painful rheumatic conditions in clinical practice. Teleradiotherapy may be a cheap, painless procedure which is applicable to many joints at a time. OBJECTIVE: To determine if the local application of x rays to inflamed joints in rheumatoid arthritis (RA) affects the signs and symptoms of inflammation. METHODS: In a randomised, controlled, double blind study, roentgen irradiation was administered in a total dose of 20 Gy during 2 weeks to single joints in six patients with RA who were receiving constant and stable pharmacological treatment with DMARDs and NSAIDs. Single inflamed joints on the contralateral side of the body were used as controls and received sham irradiation. Swelling and tenderness was assessed by blinded investigators before and until 3 months after the irradiation; general disease activity and pain scales were included in the assessment. RESULTS: No change in the scores for tenderness, swelling, pain, or disease activity was seen. The trial was stopped for ethical reasons. CONCLUSION: Local roentgen treatment of RA at a substantial dose of 20 Gy was ineffective in this pilot trial.
OBJECTIVE: To determine the prevalence and clinical impact of rotator cuff tears in asymptomatic volunteers. MATERIALS AND METHODS: Sonographic examinations of the shoulder of 212 asymptomatic individuals between 18 and 85 years old were performed by a single experienced operator. The prevalence and location of complete rotator cuff tears were evaluated. The clinical assessment was based on the Constant Score. Magnetic resonance imaging (MRI) of the shoulder was obtained in those patients where US showed rotator cuff pathology. RESULTS: Ultrasound showed a complete rupture of the supraspinatus tendon in 6% of 212 patients from 56 to 83 years of age (mean: 67 years). MRI confirmed a complete rupture of the supraspinatus tendon in 90%. All patients reported no functional deficits, although strength was significantly lower in the patient group with complete supraspinatus tendon tear (P < 0.01). CONCLUSION: There is a higher prevalence in older individuals of rotator cuff tendon tears that cause no pain or decrease in activities of daily living.
AIM: The clinical value of combined XCT/SPECT technology in a single device in patients undergoing (123)I-MIBG scintigraphy was analyzed. METHODS: 31 patients (19 men, 12 women; mean age 55 years, range: 31-79 years) demonstrating focal accumulation in planar (123)I-MIBG scan were further investigated with a double headed gamma camera with an X-ray tomograph mounted on the same gantry (GE Medical Systems, Millennium VG with Hawkeye, Milwaukee, USA) for anatomical definition of the focal (123)I-MIBG uptake. The patients were referred to (123)I-MIBG scintigraphy because of biochemically (81%) and/or clinically (19%) suspected pheochromocytoma. RESULTS: In 23 out of 31 patients (74%) the fused images demonstrated physiological accumulation (i. e. intestinal, renal) of (123)I-MIBG. In two patients (6%) suspected adrenal MIBG-accumulation was caused by inhomogeneous liver uptake. In two patients (6%) focal abdominal accumulation was correctly localised in the adrenal glands. Furthermore, the differentiation of bone metastasis from a local recurrence for phaeochromocytoma was accurately possible for two patients (6%). Adrenal lesions mimicking liver foci were correctly localised in the remaining two patients (6%). CONCLUSION: Our study demonstrates the clinical value of XCT/SPECT in a single device in patients demonstrating focal (123)I-MIBG uptake in planar scintigraphy. The combined XCT/SPECT technology provides a higher diagnostic accuracy.
OBJECTIVE: The efficacy of DMARD therapy in rheumatoid arthritis (RA) can be judged by radiological analysis. This study aimed to determine the time-dependent progression of joint damage, acute-phase response, and rates of radiologic progression in early DMARD-treated RA patients over 10 years. PATIENTS AND METHODS: We evaluated outpatient records, and radiographs of hands and feet of 54 early RA patients on DMARDs for 10 years. Radiographs were quantified by the Larsen method using recently developed quantification software. RESULTS: Radiological damage attenuated, with disease progression from baseline to Year 10 [correlation coefficient (r)=0.95, probability (p)<0.001]. Radiographic scores progressed more rapidly during the first 5 years than thereafter. Cumulative erythrocyte sedimentation rate (ESR) was strongly correlated with radiological progression (p<0.001, r=0.88). CONCLUSION: Our findings reveal a higher amount of radiographic RA progression during the first years of DMARD treatment. Thus, our data provide strong evidence for the importance of both early DMARD therapy and continuous radiographic assessments in RA.
We investigated prospectively the bone mineral density (BMD) of the proximal femur after implantation of a tapered rectangular cementless stem in 100 patients with a mean age of 60 years (16 to 87). It was determined using dual energy x-ray absorptiometry, performed one week after surgery and then every six months until the end-point of five years. The BMD increased significantly in Gruen zones 2, 4 and 5 by 11%, 3% and 11% respectively, and decreased significantly in Gruen zones 1, 6 and 7 by 3%, 6% and 14% respectively, over the five-year period. The net mean BMD did not change over this time period. The changes in the BMD were not confined to the first 12 months after surgery. This investigation revealed no change in the overall periprosthetic BMD, but demonstrated a regional redistribution of bone mass from the proximal to distal zones.
Carcinoid tumors are relatively rare neuroendocrine malignancies with an indolent clinical behavior. The majority of cases arise within the gastrointestinal tract, but they may also be encountered in other organs such as the bronchial system. While occurrence of carcinoid tumors has been reported in association with the multiple endocrine neoplasia (MEN) type I syndrome, no clear-cut risk factors have been established for the development of these malignancies. We report the case of a 50-year-old woman who was diagnosed with a pulmonary carcinoid in 2001 after having undergone allogeneic stem cell transplantation for chronic myeloid leukemia (CML) in 1997. This is the first case report of a carcinoid tumor following allogeneic bone marrow transplantation. At the moment, however, an association with CML as well as a causative role of transplantation and intake of immunosuppressants remains speculative. Apart from highlighting the occurrence of a carcinoid in this setting, our case again underscores the importance of nuclear medicine methods, i.e., somatostatin receptor scintigraphy, in staging and follow-up of patients with carcinoid tumors.
OBJECTIVE: High-resolution sonography enables a detailed assessment of intraarticular and extraarticular soft tissue abnormalities of joints affected by rheumatoid arthritis (RA). This study was undertaken to evaluate the diagnostic value of B-mode sonography and power Doppler compared with that of clinical examinations and conventional radiography. METHODS: The study group comprised 47 patients (14 men, 33 women) with different grades of RA; 31 patients were rheumatoid factor (RF) positive, and 16 were RF negative. The wrists, first through fifth metacarpophalangeal joints, and second through fifth proximal interphalangeal joints of these patients were scored with ultrasound in B-mode and power Doppler application, using a standardized technique. Involvement and severity of inflammation, as well as vascularization, were scored according to a new 3-point scale. The results were correlated with benchmarks of the clinical and radiologic investigations. Clinical status and conventional radiologic status were determined according to the Disease Activity Score and the Larsen score. RESULTS: After preliminary studies in 15 patients, 39% of 704 joints were found to be abnormal by clinical investigation. Erosions were detected by radiography and sonography in 23% and 43% of joints, respectively. Hypervascularization was observed in 34% of 704 joints by power Doppler application. There was a significant correlation (P < 0.001) between the different methods for the detection of the severity of lesions. Use of a modern, state-of-the-art power Doppler program was necessary for semiquantification, and a standardized investigation technique and scoring system provided sufficient quality measures. CONCLUSION: Sonography detects 20% more abnormalities than does radiography, and sonography has the potential to provide simple grading of disease activity. The rate of detection of abnormalities was slightly higher with clinical examination compared with sonography.
In the past years, multislice CT (MS-CT) has become an important diagnostic modality for the radiological evaluation of the thorax in children and adolescents. However, the higher stochastic radiation risks in pediatric patients, as compared to adults, necessitate a prudent use of MS-CT. This article presents an overview of the benefits of multislice CT and a variety of possibilities for radiation reduction in pediatric patients of different ages.
Recent studies in the USA and Europe state that computed tomography (CT) scans compromise only 3-5% of all radiological exams, but they contribute 35-45% of total radiation dose to the patient population. These studies lead to concern by several public authorities. Basis of CT-dose measurements is the computed tomography dose index (CTDI), which was established 1981. Nowadays there are several modifications of the CTDI values, which may lead to confusion. It is suggested to use the standardized CTDI-100 w. value together with the dose length product in all CT-examinations. These values should be printed on all CT-images and allows an evaluation of the individualized patient dose. Nowadays, radiologist's aim must be to work at the lowest maximal diagnostic acceptable signal to noise ratio. To decrease radiation dose radiologist should use low kV and mA, but high pitches. Newly developed CT-dose-reduction soft-wares and filters should be installed in all CT-machines. We should critically compare the average dose used for a specific examination with the reference dose used in this country and/or Europe. Greater differences should caution the radiologist. Finally, we as radiologists must check very carefully all indications and recommend alternative imaging methods. But we have also to teach our customers-patients and medical doctors who are non-radiologists-that a 'good' image is not that which show all possible information, but that which visualize 'only' the diagnostic necessary information.
BACKGROUND: Precise diagnosis and follow up treatment of rheumatoid arthritis (RA) requires objective quantification, which is still lacking. For this purpose, radiological analyses are considered to be the most appropriate method. OBJECTIVE: To develop computer assisted quantification software that is particularly applicable to joint scoring in rheumatic disorders. METHODS: 3914 radiographs from hands and feet of 190 patients with RA were collected, expertly examined, analysed, and statistically evaluated. Radiographs were quantified using the conventional Larsen score and the "X-Ray RheumaCoach" (XRRC) software. The XRRC is a Java stand alone application which can support and accelerate, but not fully automate, the scoring procedure in RA. The scorer can apply both the Larsen and the Ratingen-Rau scores. RESULTS: Compared with conventional scoring procedures, the XRRC software accelerated quantification time by approximately 25%. The program, which is now available on the internet free of charge, ran stably and proved to be a consistently valuable tool. CONCLUSIONS: Compared with conventional scoring methods, the XRRC software offers several advantages: (a) structured data analysis and input that minimises variance by standardisation; (b) faster and more precise calculation of sum scores and indices; (c) permanent data storing and fast access to the software's database; (d) the possibility of cross calculation to other scores; (e) "user friendly" technology and a dedicated help program; (f) fast access and data transfer through the internet if desired; and (g) reliable documentation of results in a specially designed printout.
Variable pathologies are subsumed under the term "synovial disease", including common pathologies such as rheumatoid arthritis. While formerly radiologists had to rely on conventional radiographs and bone scintigraphy with their inherent problems in visualizing soft tissue, noninvasive imaging of the synovium has recently improved substantially with the technical development of MRI and (Doppler) ultrasound. These imaging modalities allow differentiation of characteristic pathologic features based on a profound knowledge of normal anatomy and pathophysiology.
Implementation of radiological information systems (RIS) and picture archiving and communicating systems (PACS) results in significant changes of workflow in a radiological department. Additional connection with flat-panel detectors leads to a shortening of the work process. RIS and PACS implementation alone reduces the complete workflow by 21-80%. With flatpanel technology the image production process is further shortened by 25-30%. The workflow-steps are changed from original 17-12 with the implementation of RIS and PACS and to 5 with the integrated use of flatpanels. This clearly recognizable advantages in the workflow need an according financial investment. Several studies could show that the capitalisation-factor calculated over eight years is positive, with a gain range between 5-25%. Whether the additional implementation of flatpanel detectors results also in a positive capitalisation over the years, cannot be estimated exactly, at the moment, because the experiences are too short. Particularly critical are the interfaces, which needs a constant quality control. Our flatpanel detector-system is fixed, special images--as we have them in about 3-5% of all cases--need still conventional filmscreen or phosphorplate-systems. Full-spine and long-leg examinations cannot be performed with sufficient exactness. Without any questions implementation of integrated RIS, PACS and flatpanel detector-system needs excellent training of the employees, because of the changes in workflow etc. The main profits of such an integrated implementation are an increase in quality in image and report datas, easier handling--there are almost no more cassettes necessary--and excessive shortening of workflow.
Osteoarthritis of the hip joint is a very common disease. There is a minor prevalence of males. By etiology one can distinguish primary (idiopathic) from secondary osteoarthritis. Secondary are due to well-known etiologies as overweight, repetitive traumata, malposture, muscle- and tendon-imbalance etc. Osteoarthritis includes not only cartilage abnormalities, but also such of the subchondral-region, synovialis, synovial fluid and periarticular muscles. The cartilage shows in osteoarthritis typically edema and swelling, defects with tears, fibrillation, and "baldness" and (or) cartilagenous repair-islands and joint space narrowing as well, while subchondrally micro-edema, necrosis, ev. microfractures, "cysts", demineralisation followed by sclerosis, osteophyte-formation and deformity is seen. With conventional radiographs and CT joint space narrowing, subchondral cysts, sclerosis and osteophytes and deformities are well delineated, MRI however allows visualization of subtle bone marrow and cartilage abnormalities. Clinically, the diagnosis of pre-osteoarthritis becomes more and more important. This includes e.g. deformities and malpostures, labrum-pathologies and structural imbalances. There are three prognostic different types of hip-osteoarthritis depending on the migration of the head of the hip joint: the most common are the latero-cranial and the medio-caudal ones, while the central one is found very rarely. Basic imaging method are conventional radiographs, and CT, followed by MRI. The diagnosis of an "activated osteoarthritis" is made by bone-scintigraphy or MRI with i.v. application of contrast-media. The labrum- and cartilage diagnosis should be done with MRI or MR-arthrography. Functional computer-animated analysis will be of great diagnostic value in the near future. MRI indications are differences between clinical results and imaging, missing clinical improvement of an "activated" osteoarthritis under standard therapy, unclear joint-pain and before any arthroscopy.
Because of the rising popularity of recreational sports activities achillodynia is an often associated symptom with running, soccer and athletics. Therefore radiologist are frequently asked to image this tendon. The origin of the damage of the Achilles tendon is explained by numerous hypothesis, mainly a decreased perfusion and a mechanical irritation that lead to degeneration of the tendon. High-resolution technics such as sonography and magnetic resonance imaging show alterations in the structure of the tendon which can be graduated and classified. Manifestations like tendinosis, achillobursitis, rupture and Haglunds disease can summarized as the tendon overuse syndrome. A rupture of a tendon is mostly the result of a degeneration of the collagen fibers. The task of the radiologist is to acquire the intrinsic factors for a potential rupture.