Biphasic bioresorbable scaffold (TruFit®) in knee osteochondral defects: 3-T MRI evaluation of osteointegration in patients with a 5-year minimum follow-up.

PURPOSE: The aim of this study is to follow morphological imaging characteristics and osteointegration of TruFit® bone graft substitute (BGS) plugs in cases of chondral and osteochondral defects of the articular surface of the knee joint, using high-quality cartilage-sensitive 3-T magnetic resonance imaging (MRI), linked to clinical outcomes. METHODS: The MRI was used to assess osteointegration and biological evolution of the TruFit® BGS plugs in cases with minimum 5-year follow-up: The TruFit® plug was used in 46 patients for a total of 47 cases with mean age of 57.89 (range 32-80). In this study, we reviewed only the cases with minimum follow-up of 5 years: 5 patients with mean age 64.4 years (minimum 38, maximum 80). The mean follow-up was 71 months (range 63-77). Patients were evaluated clinically, with Lysholm Knee Scoring Scale and MOCART Scale. RESULTS: 3-T MRI, which is preferable to 1.5 T for the better signal-to-noise ratio, contrast and the ability to acquire morphological images at higher spatial resolution, shows a satisfactory integration of bone scaffolds in studied cases for more than 5 years and a satisfactory restoration of the articular cartilage, with the exception of a case of which we still have to consider the factors age, type of lesion and the relationship between the plugs implanted. CONCLUSION: Clinical and radiological results significantly improve in a longer follow-up time.

Ultrasonographic evaluation of liver volume and the metabolic syndrome in obese women.

Non-alcoholic fatty liver disease is a common finding in obese subjects, and increasing evidence has been provided suggesting that it represents the hepatic component of the metabolic syndrome. The aim of this study was to evaluate whether the extent of liver enlargement is related to the severity of the metabolic syndrome in obese women. The relationship between ultrasound- measured hepatic left lobe volume (HLLV) and various features of the metabolic syndrome was evaluated in 85 obese women. The mean+/-SD value of HLLV in obese women was 431+/-214 ml (range 46-1019 ml) while it was 187+/-31 ml (range 143-258 ml) in lean subjects. In a multiple logistic regression analysis, ultrasound-measured intra-abdominal fat was the only anthropometric measure independently associated with HLLV. A strong positive association was found between HLLV and serum liver enzymes, triglycerides, glucose, insulin, uric acid, C reactive protein, systolic and diastolic blood pressure, while a negative correlation was observed between HLLV and HDL cholesterol. The values of HLLV corresponding to the cut-off values of various risk factors for the diagnosis of the metabolic syndrome were calculated, yielding a mean value of 465 ml. In conclusion, ultrasound measurement of HLLV represents a simple, reliable and low-cost tool for the evaluation of liver involvement in the metabolic syndrome. The strong association between liver enlargement and various cardiovascular risk factors associated with insulin resistance supports the role of liver steatosis as an important link among the many facets of the metabolic syndrome in human obesity.

Magnetic resonance of the temporomandibular joint: experience at an Italian university center.

AIM: The aim of this investigation was to suggest criteria in order to evaluate magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ). Such criteria have been discussed on the basis of our experience at the Section of Prosthetic Dentistry, Department of Neurosciences, University of Pisa. METHODS: The study sample was constituted by 135 patients. All subjects underwent bilateral MRI of the TMJs to evaluate disc structure and position, bony structure abnormalities, joint effusion localization and entity. RESULTS: MRI allowed depiction of the articular disc in 98.9% of the TMJs, showing a normal disc structure in 91.1% of the cases and abnormal in 7.7%. The disc-condyle relationship was normal in 46.6% TMJs, while a disc displacement with reduction was revealed in 35.5% cases, a disc displacement without reduction in 16.7% and a posterior disc displacement in 1.5% joints. In the coronal images, the disc was positioned lateral to the condyle in 8.9% of the TMJs and medial in 6.7%. Osseous abnormalities have been found in 177 joints (65.5%), with cases of bony flattening (condyle and/or tuberculum), erosions, subchondral cysts, osteophytosis and sclerosis. T2 sequences showed effusion in 26.7% of the TMJs. CONCLUSIONS: These findings suggest that standardized methodology application and well-defined criteria can facilitate MR imaging observations and interpretation as well as the diagnosis of intra-articular pathologies.

Ultrasonographic vs magnetic resonance imaging findings of temporomandibular joint effusion.

AIM: The aim of this study was to assess the accuracy of ultrasonography (US) in the evaluation of temporomandibular joint (TMJ) effusion compared with magnetic resonance imaging (MRI) findings, assumed as the gold standard. METHODS: The study group consisted of 44 patients with signs and symptoms of temporomandibular disorders (TMD). Each joint (N=88) was evaluated using US and magnetic resonance (MR) to detect the presence of effusion. The 2 examinations were carried out by 2 blinded operators within no more than 2 weeks from each other. During that period the patients did not receive any kind of treatment. Sensitivity, specificity, positive predictive values (PPV) and negative predective values (NPV) of US were calculated. The agreement between the 2 diagnostic techniques was then evaluated by Cohen's K test. RESULTS: MRI depicted intra-articular effusion in 41 of the 88 TMJs (46.5%) while no effusion was detected in the remaining 47 joints (53.5%). Ultrasonographic imaging revealed effusion in 42/88 joints (47.8%), while the remaining 46 joints (52.2%) showed no effusion. US showed a sensitivity of 75.6% and a specificity of 76.5%. The PPV and NPV were 73.8% and 78.2% respectively. US vs MRI agreement for the diagnosis of TMJ effusion was fairly good (pct. agreement 76.1%; K=0.521). CONCLUSION: US is a low-cost, easy-performing, non-invasive, rapidly-executing imaging technique whose possible employ in the study of the TMJ is very promising.

Contrast-enhanced three-dimensional MR angiography of neck vessels: does dephasing effect alter diagnostic accuracy?

The aim of this study was to evaluate diagnostic accuracy of contrast-enhanced MRA (CEMRA) compared with digital subtraction angiography (DSA) in studying neck vessels of 48 patients. In three groups of patients, we used three MRA protocols differing for voxel size to assess if intravoxel dephasing effects could modify accuracy of CEMRA. Accuracy and correlation with DSA results were calculated in all patients and separately in the three groups. A qualitative analysis of the likeness between morphology of the stenosis in CEMRA and DSA images was also assessed. In all patients accuracy and agreement with DSA were 96% and k=0.85 in subclavian arteries, 96% and k=0.84 in vertebral artery, 97% and k=0.88 in common carotid arteries, and 94% and k=0.86 in internal carotid arteries. In the three groups accuracy and agreement with DSA did not show any significant difference. Qualitative analysis of CEMRA and DSA images revealed a better agreement in depicting the morphology of stenosis using a smaller voxel size. The CEMRA represents a powerful tool for the non-invasive evaluation of neck vessels. Overestimation trend of CEMRA is confirmed and the reduction of voxel size, decreasing the dephasing intravoxel effect, allows to have a better overlapping of stenosis morphology on CEMRA compared with DSA, but it does not yield diagnostic gain in the stenosis grading.

Ultrasound assessment of increased capsular width as a predictor of temporomandibular joint effusion.

OBJECTIVES: The aim of this study was to evaluate whether an increased capsular width evidenced by ultrasound (US) could be an indirect marker of temporomandibular joint (TMJ) effusion. METHODS: 138 TMJs were evaluated by US and magnetic resonance imaging (MRI) by two blinded calibrated investigators. US measures of capsular width (in mm) and MRI diagnosis of TMJ effusion (presence/absence) were used to perform a receiver operating characteristic (ROC) curve analysis in order to assess the most accurate cut-off value of capsular width that was able to discriminate between joints with and without MRI effusion. RESULTS: Diagnostic accuracy of US to detect MRI-depicted TMJ effusion was good (area under the ROC curve=0.817). US sensitivity was high for values below the cut-off value of 1.950 mm (true positive rate (TPR)=83.9%; false positive rate (FPR)=26.3%), while specificity was high for values above the cut-off value of 2.150 mm (TPR=71.0%; FPR=11.8%). CONCLUSIONS: Analysis of ROC curve appears to reveal that the critical area is around the 2 mm value for TMJ capsular width. These findings need to be refined by further studies assessing the smallest detectable difference in capsular width, with attention to reliability of interobserver observations.

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.

Contrast-enhanced three-dimensional MR angiography in the assessment of subclavian artery diseases.

The purpose of this prospective study was to determine the potential diagnostic value of 3D breath-hold contrast-enhanced MRA (CEMRA) in the evaluation of subclavian artery pathology, and to compare CEMRA and digital subtraction angiography (DSA) findings. The study group included 50 patients with suspicion of subclavian artery pathology: 40 suspected steno-occlusive disease and 10 different vascular anomalies. The MRA examinations were performed on a 1.5-T system using fast 3D sequences. A fixed dose of 40 ml Gd-DTPA was administered at 2 ml/s after previous bolus tracking. Images were analyzed to assess: subclavian depiction; luminal changes; collateral branches; and feeders of arterial venous malformations (AVM). A multireader blinded fashion was used. The CEMRA revealed an optimal agreement with DSA findings in the different types of diseases. Sensitivity and specificity were 90 and 95%, respectively, in detecting steno-occlusive disease (including functional and arteritic stenoses), and 100 and 100%, respectively, in cases of vascular anomalies (dilation, kinking, anomalous origin and AVM). Contrast-enhanced MRA can be proposed as a non-invasive, robust technique for imaging subclavian pathologies with high diagnostic performance.

[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.

High-resolution magnetic resonance and volume rendering of the labyrinth.

Our aim was to verify the feasibility of volume rendering (VR) of high-resolution magnetic resonance (HR-MR) data sets of the labyrinth. We retrospectively reviewed the HR-MR data sets of 16 consecutive patients with no MR evidence of labyrinthine pathology. High-resolution MR data sets were obtained by means of a 3D T2-weighted FSE sequence with the use of a 3-in. circular surface coil for signal reception, and processed with a high-end workstation. Two reviewers performed separately VR of the labyrinth by selecting the signal intensity interval for attribution of opacity and transparency. Concerning the time taken for definition of the volume of interest, the two observers needed, respectively, 28.9 and 33.1 min (SD +/- 8.7-9.5 min), whereas the time taken for VR was respectively, 26 and 33.2 min (SD +/- 8.8-8.9 min). Concerning the selection of the signal intensity interval, the two observers had, respectively, 86.4 and 88.7 mean lower threshold (SD +/- 34.5-33.5), 488.9 and 495.4 mean upper threshold (SD +/- 56.3-53.8). In our experience, we have found VR of HR-MR to offer a reliable and reproducible technique for producing 3D representations of the labyrinth. The VR algorithms use all data within the imaging volume and optimize the dynamic range ascribed to the object being visualized.

[Anterolateral fibrous impingement of the ankle. Report of 14 cases]. / Conflitto fibroso antero-laterale della caviglia. Descrizione di 14 casi.

PURPOSE: Anterolateral fibrous impingement of the ankle is one of the causes of post-traumatic pain in the foot. We investigated the comparative accuracy of US and MRI in this condition. MATERIAL AND METHODS: Fourteen patients were submitted to arthroscopy, plain radiography, US and MRI of the foot. The patients, all sportsmen, had a clinical history of sprains; the major symptoms were pain, swelling and clicking on foot dorsiflexion. RESULTS: US showed anterior talofibular ligament changes in all patients and mid-low-echogenicity synovial tissue filling the lateral malleolar gutter. MRI demonstrated a small mass of synovial tissue in the gutter in 8 patients, with mid-low signal intensity before Gd-DTPA and mid-low contrast enhancement after contrast administration and no abnormal findings in 6 patients. Arthroscopy showed a small firm mass of proliferative synovium in the lateral malleolar gutter in all patients. CONCLUSIONS: Fibrous impingement must be suspected in the sportsmen presenting typical symptoms after ankle trauma. US is poorly accurate in diagnosing this condition. MRI shows a small synovial mass in the lateral malleolar gutter in more than half the patients, but aspecific MR findings do not rule impingement our MR images must be acquired along the proper planes and with Gd-DTPA administration.

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.

[Osteochondral lesions of the humeral head: the usefulness of echographic study]. / Lesioni osteocondrali della testa omerale: utilità dello studio ecografico.

PURPOSE: In the cranial humeral end, osteochondral injuries localize in a circular crown including part of the humeral head and part of the major and minor tuberosities. Since this region is easy to depict with US, we investigated the potentials of this technique in detecting osteochondral injuries. MATERIALS AND METHODS: Seventy-five osteochondral injuries found at 492 US examinations performed in 12 months with a 7.5 MHz linear probe were retrospectively reviewed. Clinical history taking was focused on the following: a) previous trauma or b) luxation-instability and c) if the patient was a sportsman devoted to activities requiring forced abduction-external rotation or adduction-internal rotation. Since the site of the head's humeral injury is an important clue for diagnosis, we subdivided the humeral circle into four ideal quadrants by two perpendicular lines with the main line passing through the bicipital groove. Then, each injury was ascribed to a quadrant. All patients were also submitted to radiography (at least two films) and to MRI; CT was performed in 12 patients. Ten patients underwent surgery. RESULTS: We found 34 Hill-Sachs lesions, 15 traumas, 9 arthrotic lesions, 7 cases of anterointernal and 4 of posterosuperior impingement, 4 cases of infraspinatus enthesopathy and 2 erosions due to perihumeral calcifications. In our experience, US was an accurate tool in the identification of humeral head conditions, which were confirmed at CT and/or MRI in all patients (no false positives). As for the injury nature, US diagnosis was confirmed in all Hill-Sachs lesions (34/34 cases), traumas (15/15 cases) and 50% of the cases of posterosuperior impingement (2/4 cases). These conditions made up about 2/3 of the whole cases (51/75 cases). US failed to establish the injury nature in the 9 arthrotic lesions, 7 cases of anterointernal impingement, 4 cases of infraspinatus enthesopathy and 2 erosions due to perihumeral calcifications. CONCLUSIONS: US can be suggested as the method of choice in the study of the osteochondral lining of the humeral head.

[Comparison of computerized tomography and magnetic resonance in the assessment of benign and malignant pleural diseases]. / Confronto fra Tomografia Computerizzata e Risonanza Magnetica nella valutazione delle malattie pleuriche benigne e maligne.

To compare the diagnostic capabilities of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) in differentiating benign from malignant pleural disease, we examined with MRI at 0.5 T forty-five patients with pleural lesions identified on CT scans. For 34 patients, a final diagnosis of malignant (n = 18) or benign (n = 16) disease was made. T1, proton density/T2 and enhanced T1-weighted spin-echo images were acquired. CT and MR images were independently studied by two observers, who were unaware of the final diagnosis. Various morphological features suggesting benign or malignant pleural disease were evaluated. On the basis of the morphological CT features, a final diagnosis of benignity of malignancy was expressed in terms of two different levels of confidence-probable or definitive. The MR signal intensity of pleural lesions was compared with that of intercostal muscles (isohypointense or hyperintense). No significant differences were observed between CT and MR morphological findings. High signal intensity on proton density/T2-weighted images was observed in all malignant lesions and in 2 benign lesions (100% sensitivity, 87% specificity). In the absence of this sign (i.e., isointense or hypointense signal), the lesions were always benign (100% negative predictive value). All the definitive CT diagnoses were correct, while 6 of 17 probable CT diagnoses were incorrect. In the subgroup of lesions misinterpreted with CT, MR signal intensity on long-TR images always allowed the correct differentiation of benign from malignant conditions. To conclude, MR signal intensity is a valuable additional feature to differentiate benign from malignant pleural disease. We suggest the use of MRI in the pleural lesions where the level of confidence of CT diagnosis is low.

MRI of cerebellar white matter damage due to carbon monoxide poisoning: case report.

Extensive bilateral cerebellar white matter signal change, with sparing of the overlying cortex, consistent with demyelination was seen in a 12-year-old boy who had suffered carbon monoxide poisoning 6 years previously. His youth at the time of exposure and the long delay between exposure and examination might account for this unusual finding.

Usefulness of MR signal intensity in distinguishing benign from malignant pleural disease.

OBJECTIVE: The aim of this study was to analyze the potential usefulness of MR signal intensity in differentiating malignant from benign pleural disease. SUBJECTS AND METHODS: Forty-five patients with pleural lesions identified on CT scans were subsequently examined by MR imaging at 0.5 T. T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted spin-echo images were obtained. For 34 patients, a diagnosis of malignant (n = 18) or benign (n = 16) disease was established. The morphologic features of the pleural lesions and MR signal intensity on T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted images were evaluated, and the ratio of lesion to muscle signal intensity was computed. RESULTS: Assessment of morphologic features by MR imaging and CT was not significantly different. High signal intensity on proton density-weighted and T2-weighted images was observed in all malignant lesions and in two benign lesions (sensitivity, 100%; specificity, 87%; negative predictive value, 100%). The ratio of lesion to muscle signal intensity on T1-weighted, proton density-weighted, T2-weighted, and enhanced T1-weighted images discriminated between malignant and benign lesions (p < .0001). For the subgroup of lesions misinterpreted by CT (n = 6), the evaluation of MR signal intensity on long-TR images made it possible to differentiate malignant from benign conditions. CONCLUSION: MR signal intensity is a valuable additional feature for differentiating malignant from benign pleural disease. Signal hypointensity with long-TR sequences is a reliable predictive sign of benign pleural disease.