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Rationale and Objectives: There is a continuing need for a greater sensitivity of magnetic resonance imaging (MRI) in the diagnosis of avascular necrosis (AVN). Previously, it was demonstrated that a dynamic MRI method, with gadolinium-DTPA (Gd-DTPA) enhancement, can detect acute changes not seen on spin-echo images after arterial occlusion in a dog model. Because venous congestion appears to be a more directly relevant hemodynamic abnormality in a majority of clinical AVN cases, the authors extended the dynamic MRI technique to study changes in venous occlusion., Methods: Dynamic MRI of the proximal femur was performed in five adult dogs before and after unilateral ligation of common iliac and lateral circumflex veins. Sixteen sequential gradient-recalled pulse sequence (GRASS) images (time resolution = 45 mseconds, echo time = 9 mseconds, flip angle = 65 degrees) were obtained immediately after a bolus intravenous injection of 0.2 mmol/kg of Gd-DTPA. Simultaneous measurements of regional blood flow were made using the radioactive microsphere method., Results: After venous ligation, there was a 25% to 45% decrease in the degree of enhancement compared with preligation values on the ligated side. The decrease in cumulative enhancement (integrated over the entire time course) was statistically significant. The occlusion technique was verified by confirming a statistically significant decrease in blood flow determined by the microsphere method., Conclusions: Dynamic Gd-DTPA-enhanced fast MRI technique can detect acute changes in bone marrow perfusion due to venous occlusion. This technique may have applications in the early detection of nontraumatic AVN.

The goal of this paper is to provide information about pregnancy in adolescents and to influence those people who have to do with the situation of pregnant adolescents and the family and social consequences. The research was carried out at the Dr. Carlos Diez del Ciervo Hospital from 1989 to 1990. It included 1,500 cases and the variables considered were mothers' age, marital status, number of gestations, number of childbirth, residence and initiation of sexual life. The main findings are stated in detail.

To determine the contribution of Gd-DTPA to the evaluation of vertebral infections 16 MR examinations with i.v. Gd-DTPA injection were performed on 12 patients with diagnosis of spondylodiscitis. All patients were examined with both SE T1- and SE T2-weighted sequences. The SE T1-weighted sequence was repeated following i.v. Gd-DTPA injection (0.1 nmol/kg). Signal intensities and visibility of the lesions were evaluated with MR. For each lesion the grade of visibility on SE T1-weighted sequence was compared with the grade of visibility on SE T2-weighted sequence. Moreover, for each study the information obtained by the combined evaluation of SE T1-weighted sequence without and with Gd-DTPA was compared with the information obtained by combined SE T1- and SE T2-weighted sequences. Gd-DTPA was useful in the evaluation of lesions of the discal space, showing in all cases an area of low signal intensity with peripheral enhancement; this finding allowed, in some cases, to differentiate mild spondylodiscitis from degenerative features. Gd-DTPA was also very useful in determining the extent of the disease: in comparison with MR study without contrast media, the combined evaluation of SE T1-weighted sequence without and with Gd-DTPA better showed the extent of the disease in 7/8 cases (88%).

Magnetic resonance imaging has opened new possibilities to current diagnostic radiology in the evaluation of bone marrow. In the past, bone marrow imaging was based on conventional radiology, nuclear medicine and computed tomography; they all exhibited some capabilities but also some limitations. Bone image on MR scans is due to bone marrow, with its different components of red and yellow marrow. Since red marrow is mostly liquid and yellow marrow contains large amounts of fat, the signal will vary, on T1-weighted images, according to their different proportions. There is a gradual change from red marrow to yellow marrow from birth to adulthood: this change determines the MR appearance of bone marrow, the different features of which should be known for a correct evaluation of pathologic findings. MRI is extremely effective in the evaluation of infiltrative disorders of bone marrow, such as leukemia, lymphoma, myeloma, primary and metastatic skeletal tumors, and infections. MRI allows depletive disorders of bone marrow and ischemic processes to be studied. Finally, MRI allows the non-invasive follow up of bone marrow pathologic conditions, thus representing a valid alternative to biopsy.

Skeletal infections represent a variety of clinical and pathological conditions in which both an early diagnosis and the precise evaluation of disease extent are very important in planning proper therapy. To determine MRI capabilities and limitations in the evaluation of skeletal infections 21 patients--12 with a clinical diagnosis of osteomyelitis of the lower limbs and 9 with a clinical diagnosis of spondyloscitis--were studied with this technique. All patients were examined with conventional X-rays; conventional tomography was performed in 3 cases, and CT in 6. Signal intensities and morphological aspects were then evaluated with MRI. MRI diagnoses were compared with surgical findings or clinical follow-up, after antibiotic therapy: 19 true-positives were observed, together with 1 true-negative, 1 false-positive, and no false-negatives. MRI findings were correlated with those of conventional radiology: MRI identified the lesions and their nature in 100% of cases, whereas conventional radiology did the same in 85% of cases; in 50% of cases only the latter was able to define the nature of the process. Four patients underwent MRI follow-up. MRI was highly sensitive in determining the presence of lesions in an early stage and in demonstrating lesion regression. Moreover, MRI was able to identify the complications occurring in some cases of osteomyelitis and spondyloscitis. In all cases MRI allowed the extent of the disease to be accurately determined and, in osteomyelitis of the lower limbs, it was extremely useful to differentiate soft-tissue infections from bone marrow involvement.

The general requirements are analyzed of a system designed to acquire and manage radiological data of scientific interest. These requirements consist in: easy implementation, to develop the system in the same environment where it is going to be used; easy use, to avoid excessive needs and resources for the system to be managed in practice; reduced implementation cost, in terms of resources required for its implementation; user-oriented approach, in the sense of meeting the radiologists' requirements, and flexibility, for the system to be an effective tool for the widest range of possible applications. Two actual applications of this general approach are then discussed, one relative to breast investigations data, and the other to digital procedures (US, CT, DSA, MR) data. For each application the software tools employed are analyzed, together with the archive structures and the used codes, the collecting data procedures and the programs. For the breast investigations archive the possibility of obtaining standard periodic reports is pointed out. These reports summarize the global department activity in this area during selected periods (six months-one year). They allow interesting clinical conclusions to be drawn. As for the digital procedures archive, the possibility is stressed of searching different combinations of scientific data out of tens of thousands of cases in just a few minutes.

"Analysis of 29 cases evaluated at SMG, Rochester, N.Y." This study analyzed 29 patients with the diagnosis of medulloblastoma evaluated at Strong Memorial Hospital, Rochester, New York. Twenty-three patients received combined (surgery and radiotherapy) treatment. Six had surgery alone. Chemotherapy was never employed as a primary treatment, however, two cases were treated with drugs at the time of relapse. The patients having craniospinal irradiation had a better survival rate when compared with the group receiving cranial irradiation or surgery alone. The five year survival rate for the first group was 50% versus 20% for the second group and 0% for the third group. The main cause of failure was recurrence in the posterior fossa. Fifteen patients failed in this area representing 88% of the total failures. Seeding to the spinal cord was determined in 5 patients, four of whom did not have spinal cord irradiation. One patient failed outside the field of treatment in the conus medullaris six months after radiation.

Six patients with diskitis following lumbar disk surgery were investigated by Computed Tomography (CT). Four patients underwent CT in a rather early phase of the disease (5-37 days after the onset of the symptoms): a posterior paravertebral fluid collection was always recognized, while the plain film was normal. Later on (2-4 months), the classical signs of diskitis were evident, with both CT and the plain film. The collection was always present at CT. A reintervention, performed on 3 patients, revealed the purulent content of the collections. It seems reasonable to suggest a relationship between the collection and the subsequent diskitis; the collection is probably an early sign of the disease. Its detection is of great value, because it could allow an immediate and adequate therapy. The authors stress the usefulness of performing CT in an early phase on this kind of symptomatic patients.

Sera obtained from 212 patients with rhinopathy and/or asthma of allergic origin (pollens and/or mites) and from 87 apparently healthy controls were studied for the presence of organ and non organ specific autoantibodies. These were determined by indirect immunofluorescence techniques (5) using test tissue from monkeys (thyroid) and rats (stomach, liver and kidney). Two groups were matched for age and sex and the tests were performed using the double-blind method. The incidence observed was not dissimilar to that detected in healthy subjects, with the exclusion of smooth-muscle antibodies. These were present to a lesser extent in patients with respiratory allergies (0.94%) in contrast with the incidence of 5.73% in normal subjects (P less than 0.01). On the basis of our findings, it seems possible to hypothesize that allergic patients have a lesser tendency to autoimmune diseases because the immune system is committed to the IgE-mediated immunoreactions. In conclusion, autoantibodies do not seem to play a role in the pathogenesis of respiratory allergies to inhaled allergens.

The Radiology Information System (RIS) for the management of the Radiology Department at the Trieste University Hospital is here presented. It consists of 3 subsystems: the first one is devoted to the management of the patients archive and to the examination scheduling function, the second deals with the statistical and administrative reporting task, and the third manages the archives of scientific data. Each subsystem is analysed in details, in terms of functions, hardware, software, archives, and personnel. The actual implementations of such systems are considered, with respect to the main functions of the Radiology Department, on the basis of the authors' actual experience. An attempt is made to set aside features related to the local situation, thus providing useful data for different realities. Specific quantitative measures are presented, whenever appropriate, to provide a solid ground to explain and motivate the most relevant aspects relative to the management of the Radiology Department in general and of the RIS in particular. Workloads and/or execution times of the main functions were collected and the RIS has turned out to yield significant benefits (e.g., easier and more confident access to the information). On the other hand, the costs are not negligible and must be carefully planned during the projecting phase. Some expected future developments of the RIS are outlined: in the short run the network conversion is devised, and a functional integration among the subsystems; in the medium run an autonomous system is planned, and in the long run a connection is considered with a Picture Archiving and Communication System (PACS) and with the Hospital Information System (HIS).

The study of soft tissues has greatly improved since the introduction of ultrasonography (US) and computed tomography (CT). In order to define the role of instrumental investigations, 51 patients affected by non glandular superficial soft tissue masses underwent US and 9 were also examined with CT. US proved to be accurate to define the size, the structure of the mass (93%), the benign or malignant nature (91%). US was also useful for percutaneous biopsy. However, US cannot be considered the only investigation because it does not give enough data about bony and articular structures: a conventional X-ray film must be performed in order to define the relation of the mass with the adjacent bone and to clarify the possible presence of fatty tissue in a solid mass shown at US. CT has a role in case of large masses, surrounding a bone diaphysis, when the malignant nature is suspected and to define the relationship with vessels and muscles.

Computed tomography (CT) without contrast medium is largely applied to the study of intervertebral disk pathology in the lumbar spine, but has not been widely accepted in the cervical spine, due to technical and anatomical limitations. For these reasons many neuroradiologists still prefer myelography or myelo-CT. CT may yield better results if combined with iv contrast medium injection, which allows a better visualization of disk herniation. This technique is aimed at enhancing the density of the venous plexus which is located close to the intervertebral disk, the vertebral bodies and the neural foramina. A better contrast enhancement is thus obtained between the disk and the spinal cord. The authors' experience is based on 61 patients who underwent contrast enhanced CT; in 22 cases myelography and myelo-CT were also performed. The authors describe their technique and the most frequent CT findings of disk herniation: the typical finding includes a focal hypodensity surrounded by a linear blush, due to a posteriorly dislocated epidural vein. The posterior linear blush alone may be present in few cases. Contrast-enhanced CT is very useful in the study of disk pathology of the cervical spine, even when compared with myelography and myelo-CT, due the increase in the density of epidural plexus it allows. However, the technique must be very accurate if the same results as those of myelo-CT are to be obtained.

The authors have evaluated bone mineral content in the vertebral spongiosa by means of Computed Tomography. The method proposed by Genant and Cann has been applied to examine 164 healthy volunteers and 108 patients. Both healthy males and females showed a progressive bone mineral loss increasing with age; the bone mineral loss was most severe in females during the 4th and 5th decade of life. Pathology included patients with osteoporotic fractures (vertebral and femoral neck), patients with partial gastrectomy, renal failure, primary hyperparathyroidism, Cushing syndrome, corticosteroid therapy. Bone mineral values were significantly lower in most pathologic groups. Computed Tomography proves thus to be a valuable method to assess bone mineral content and to identify patients at risk for fractures.