Location of functioning metastases from differentiated thyroid carcinoma by simultaneous double isotope acquisition of I-131 whole body scan and bone scan.

In a young patient with differentiated thyroid carcinoma (DTC), previously submitted to total thyroidectomy and I-131 therapy for ablation of thyroid remnant, a follow-up 1-131 diagnostic whole body scan (WBS) demonstrated four small abnormal I-131 uptake areas. Two of these were projected over the thoracic region and corresponded to lung nodules, as later demonstrated by lung computerized tomography (CT)-scan. The remaining two areas were found in the lumbar-pelvic region, but their precise location could not be determined. Standard bone Rx examination and bone scan were negative. After I-131 therapy, we simultaneously acquired a I-131 WBS and a Tc-99m oxidronate bone scan by setting a dual window on the gamma camera. Comparing the I-131 and bone images we were able to identify the 4th lumbar vertebra and right ilium as the bone segments to be studied by a radiological approach. Eventually, the thin slice CT-scan demonstrated the presence of two small osteolytic lesions in these areas. In conclusion, the simultaneous acquisition of images both from I-131 and a bone-seeking agent may be useful to locate functioning bone metastases from DTC.

Biochemical and ultrasound tests for early diagnosis of active neuro-osteoarthropathy (NOA) of the diabetic foot.

OBJECTIVES: To test the effectiveness of a combined approach to an early diagnosis of neuro-osteoarthropathy (NOA) of the diabetic foot, we studied a group of outpatients with active NOA, presenting for the first time to our Diabetic Foot Clinic in 1998, by means of an integrated approach designed to assess bone turnover. PATIENTS AND METHODS: Fifteen consecutive diabetic patients (five Type 1 and ten Type 2 diabetic individuals, age 61.9+/-12.2 years, diabetes duration 18.7+/-8.9 years, HbA(1c) 8.4+/-1.5%) with active NOA (Group 1) were compared to nine diabetic patients with chronic stable NOA (Group 2), 14 neuropathic diabetic patients without NOA (Group 3), 13 non-neuropathic diabetic patients (Group 4) and 15 healthy controls (Group 5). Determination of serum carboxy-terminal collagen telopeptide (ICTP), bone alkaline phosphatase isoenzyme (B-ALP), osteocalcin (BGP) concentrations, as well as urinary excretion of deoxypyridinoline (DPD) were obtained in all individuals for assessment of bone reabsorption and new bone formation. Moreover in all individuals quantitative ultrasound (QUS) of the calcaneal bone was performed and mass density of lumbar spine and femur bone was determined by dual-energy X-ray absorptiometry (DEXA). RESULTS: QUS was significantly lower in the active NOA patients as compared with other groups (P<0.01), while ICTP was higher in both NOA groups (P<0.01). Urinary DPD was higher in the neuropathic non-NOA group (P<0.01) than the other groups, and osteocalcin was higher in healthy controls compared to diabetic patients without NOA. QUS and ICTP were inversely correlated (r=0.44, P=0.000). QUS in the active NOA group was significantly (P<0.01) lower in the affected compared to the unaffected foot. CONCLUSION: Our results indicate a possible role for an integrated approach to the diagnosis and monitoring of NOA involving the diabetic foot. DPD may identify patients at-risk for NOA, ICTP could be tested as a marker for NOA in asymptomatic cases. Finally, QUS of the calcaneal bone may be useful in discriminating active versus quiescent phases.

[Usefulness of opposed-phase gradient-echo technique in the diagnosis of occult lesions of the knee and comparison with traditional T1-weight sequences (in-phase)]. / Utilità della tecnica Gradient-Echo in opposizione di fase nel rilievo delle lesioni occulte del ginocchio e confronto con le sequenze T1-pesate tradizionali (in fase).

PURPOSE: To investigate the usefulness of opposed-phase gradient-echo (GRE) technique in detecting occult posttraumatic bone injuries in the knee. Occult injuries account for pain and, if not properly treated, may progress to severe chondral and bone damage. An early diagnosis provided by MRI can help avoid interventional procedures. MATERIAL AND METHODS: We submitted to MRI of the knee 51 patients (32 men and 19 women) with negative plain radiographic findings and at least one traumatic bone injury at MRI. MR examinations were performed with a 0.5 T unit and included a conventional SE or GRE T1-weighted sequence and an opposed phase GRE sequence on the coronal or sagittal plane (2-3 minutes acquisition). To assess the lesion number and conspicuity, images were retrospectively reviewed by two readers. Injury conspicuity was graded as: 0 (poorly visible), 1 (visible), and 2 (well visible). Marrow-to-injury signal intensity ratio was calculated in 30 patients: a ROI was positioned in the site of highest signal intensity and adjacent bone marrow and the ratio analyzed with Student's "t"-test. RESULTS: In-phase and out-of-phase images showed 71 injuries in 51 patients. Conventional (in-phase) imaging missed 6/71 lesions. Injury conspicuity on out-of-phase images was of grade 2 in 58 cases (81.6%) and of grade 1 in 13 cases (18.3%), versus 23 (32.3%) and 42 (59.1%), respectively, on conventional images. Injury conspicuity was graded as 0 in 6 cases (8.4%) on conventional images. Quantitative analysis of marrow-to-injury signal intensity ratio showed higher values for out-of-phase GRE than conventional images. CONCLUSION: Opposed-phase GRE are quick sequences available on all MR systems which appear superior to conventional T1-weighted images in detecting occult injuries in the knee. Injuries are more conspicuous because their signal intensity is lower due to the simultaneous presence of fat and water protons, which is typical of bone trauma, GRE sequences make a useful and rapid complement to T1-/T2-weighted fat saturation acquisitions in the study of the post-traumatic knee.

Reflex sympathetic dystrophy syndrome with microtrabecular fracture in a patient with osteogenesis imperfecta.

A case of reflex sympathetic dystrophy syndrome (RSDS) in a patient with osteogenesis imperfecta (OI) is reported. We discuss the association of OI, manifested by microfractures of the trabecular bone due to marked bone fragility, and the appearance of RSDS. Magnetic resonance imaging (MRI) was helpful in assessing the presence and extent of the trabecular fractures.

[Study of bullous fibrosis of the upper lobes in ankylosing spondylitis with high-resolution computerized tomography]. / Studio della fibrosi bollosa degli apici polmonari nella spondilite anchilopoietica mediante Tomografia Computerizzata con alta risoluzione.

The fibrobullous disease of the upper lobes is an uncommon extraspinal complication of ankylosing spondylitis. We report the conventional radiographic and High Resolution Computed Tomographic (HRCT) findings in the fibrobullous disease of the upper lobes in ankylosing spondylitis. From 1988 to 1994, four patients affected with ankylosing spondylitis, with radiographic involvement of the upper lobes, came to our observation. All patients underwent a chest X-ray exam and the previous chest X-rays carried out 2-25 years earlier were reviewed. Within 15 days, HRCT was performed, during inspiratory apnea. In all cases, repeated bronchoscopies were available, showing bronchial inflammation, together with cytologic tests and bronchial fluid cultures, which revealed no development of mycobacterium tuberculosis. The most frequent CT findings were pleural thickening, fibrotic consolidation and thickening of interlobular septa. Bullae, nodules and ground-glass areas were less frequent findings. The standard chest X-ray exam demonstrated, with the same sensitivity as HRCT, pleural thickening, bullae, nodules and volume loss in the involved lung. However, interlobular septa thickening was depicted only in one case, while bronchiectases and ground-glass areas were not recognized at all. Three temporally distinct patterns of apical involvement (infiltrative, interstitial and fibrobullous) were identified. In conclusion, HRCT was more sensitive and more specific than chest X-rays in the study of the fibrobullous disease of the upper lobes in ankylosing spondylitis.

Multiple and reversible osteolytic lesions: an unusual manifestation of behcet's disease.

We describe a patient with Behcet's disease (BD) who developed multiple and reversible osteolytic lesions during the course of disease. The possible relationships between BD and this very unusual manifestation are discussed.

[The compression of numerical radiological images]. / La compressione delle immagini radiologiche numeriche.

A digital radiological image is made by a number of pixels, each of them characterized by a definite numerical value obtained by quantization which represents the luminance in that specific image unit. Spatial resolution and dynamic range are the main factors in determining the quality of a digital radiological image. The product of the two above factors defines the global dimensions of the image and is expressed in bits. In conventional radiographic images the global dimension of the image is expressed in MBytes, because of its high spatial and contrast resolution. To reduce the visualization and storage requirements as well as the transmission time of large image data sets, compression algorithms have been recently introduced. These algorithms are based on the fact that often in a digital image parts of the binary data are "redundant", that is they are not necessary for correct image representation. Therefore, compression methods are aimed at reducing both statistical and perceptive redundancy. Statistical redundancy is reduced by means of lossless coding which does not allow to compress images with a ratio higher than 4-5:1 and that--by definition--allows to recover the original image quality. On the other hand "lossy" compression algorithms, which eliminate the perceptive redundancy, are based on the reduction of spatial resolution and dynamic range and on transform-based methods. In particular, the latter have usually been more successful in terms of efficient compression, even when applied to conventional radiographic images. The basic transform procedure can be modified at various levels. JPEG is one of these methods, originally developed for photographic images, which can be usefully applied to radiological images as well. Lossy procedures allow to reach higher compression ratios than lossless methods, but the decrease in information content must be prevented from reducing diagnostic accuracy. In order to assess the diagnostic efficiency of the images compressed with lossy methods, semi-objective analyses are usually performed and ROC curves are produced and evaluated. A model ROC analysis is presented.

Ossification of the posterior longitudinal ligament in one of a pair of identical twins concordant for ankylosing spondylitis.

A pair of identical twins suffering from ankylosing spondylitis is reported. One brother developed an earlier-onset disease and showed ossification of the posterior longitudinal ligament and the flavum ligament in his cervical spine.

A computer-assisted method for the study of the trabecular bone of the distal radius on conventional radiographs.

The procedure described is based on the acquisition and processing of x-rays of the distal radius obtained under standard conditions. An x-ray was obtained of the forearm together with an aluminum step wedge to automatically normalize the photometric values of the bone with respect to the photometric values of the reference aluminum wedge. Densitometric values for thickness (T) and a coarseness parameter (C) that depends on the trabecular bone pattern are measured on interactively selected rows and regions of interest (ROIs) of the digital image. Twenty-five women were examined and two different measurements were performed. The first measurement considers C in three sites of the radial epiphisis. The trabecular bone coarseness appears to increase from the distal to the very-very distal site and the value of C in the very distal site, which is located 1 cm distally to the distal one tenth of the radius, seems to be related to the pathological variations more than the value of C in the other sites. The second measurement is the C/T ratio of eight ROIs of 15 patients: five healthy and 10 osteoporotic women. This ratio is significantly different for the two groups in all the eight ROIs and the variations are particularly significant at 6 to 12 mm from the subchondral line.

[Impact of high resolution computerized tomography on the clinical assessment of pulmonary interstitial diseases]. / Impatto della tomografia computerizzata ad alta risoluzione sull'inquadramento clinico delle interstiziopatie polmonari.

Our purpose is to define the morphological patterns of interstitial lung disease on CT and to evaluate the diagnostic impact of high-resolution technique (HRCT). Sixty-six consecutive patients with proven interstitial lung disease were considered in our study. The basic morphological patterns include: a) large reticular pattern (10-25 mm); b) small reticular pattern (2-3 mm); c) intermediate reticular pattern (5-10 mm) with cystic dilatation of distal airspaces; d) nodular pattern; e) high-density parenchymal areas. Topography of the involved areas (peripheral, middle and axial compartments), and lesion distribution with reference to the secondary pulmonary lobule (centrilobular, perilobular, panlobular, bronchovasal) are additional diagnostic criteria. The identification and correlation of these three parameters proved very useful in limiting the range of diagnostic possibilities to interstitial disease, obviously considering clinical data. In our series a correct CT diagnosis was obtained in 57 of 66 cases (86.36%). In 24 of them (36.34%) diagnosis corrected a previous erroneous or generic clinical suspicion. Our data suggest that HRCT is indicated in interstitial lund disease when neither clinical nor radiographic findings allow a specific diagnosis to be made.

[Loco-regional transcatheter thrombolysis]. / Trombolisi loco-regionale transcatetere.

Eight cases of recent arterial thrombosis (average time of symptoms: 11 days) are considered: 2 popliteal and 6 prosthetic thromboses (2 aorto-bifemoral and 4 femoropopliteal by-passes). After percutaneous catheterization, with catheter tip either in contact with or inside the thrombus, urokinase was locally injected (200,000 UI bolus, and 75,000 UI with slow infusion for 24 +/- 72 hours); general heparin treatment was also administered. PTA was employed in 2 cases (1 surgical anastomosis and 1 popliteal thrombosis). Arterial recanalization was always obtained within 72 hours in 2 aorto-bifemoral and in 1/4 femoropopliteal by-passes. Patency was also obtained in the 2 popliteal thrombosis.