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M Midiri

Publications and source records attributed to M Midiri.

85 records · Page 5Linked to original sources
PubMedDate not supplied

[Os trigonum tarsi syndrome. Role of magnetic resonance].

INTRODUCTION: The os trigonum tarsi is an accessory bone of the foot localized posterolateral to the lateral tubercle of talus. It is usually an asymptomatic condition. However, particular activities such as ballet, soccer, or football may cause repeated stress and chronic microtraumas to the hindfoot, resulting in the os trigonum syndrome. Pain is typically localized anterior to the Achilles tendon; nevertheless, diagnosis may be very difficult because other conditions may show the same symptoms. Radiography can only demonstrate the os trigonum and its morphostructural changes, while MR imaging can also depict associated soft tissue damage. We report on 9 cases of os trigonum tarsi syndrome studied with MR imaging. MATERIAL AND METHODS: Nine patients with the os trigonum tarsi syndrome were submitted to MRI. All the examinations were performed with the patients in supine recumbency with the injured foot in neutral position and then in forced plantar flexion. Axial and sagittal T1 SE, T2* GE and FIR images were acquired. We evaluated os trigonum location and shape, signal intensity of bone, cartilages and adjacent soft tissues, and possible associated tendon injuries. RESULTS: No changes were found in the os trigonum location and shape. Signal intensity changes were seen in 2/9 cases. Particularly, a small area of very high signal intensity, due to necrosis, was depicted on the talar aspect in 1 case; a subchondral spot of slightly increased signal intensity, with a low-signal outline, was seen on the calcanear aspect in another case. Disruption of the cartilaginous synchondrosis between the accessory navicular bone and the posterior tibial aspect was observed in 7/9 patients. Tenosynovitis of the flexor hallucis longus was associated in 6/9 patients. Pseudoarthrosis with irregular bone margins and high-signal spots within the cartilage was found in 3 cases. Finally, fluid effusion surrounding the os trigonum and adjacent soft tissues was always detected. DISCUSSION AND CONCLUSIONS: The os trigonum syndrome may result from chronic microtraumas. Indeed, forced plantar flexion may cause os trigonum compression between the posterior aspect of the tibial malleolus and the calcaneus, with disruption of the synchondrosis with the lateral tubercle of talus. Joint inflammation may be associated with possible development of pseudoarthrosis. Other possible complications are related to vascular changes which may lead to bone necrosis. Furthermore, the particular anatomical site of the os trigonum may sometimes cause compression to the flexor hallucis longus tendon, resulting in severe tenosynovitis. MR imaging allows complete morphostructural assessment because it depicts the margins and the signal intensity of bone and ligaments on the 3 spatial planes. Particularly, sagittal T2 images best demonstrate the cartilage changes indicating synchondrosis disruption. This condition may cause abnormal mobility of the accessory bone with possible impingement with the posterior aspect of the tibia, or hypomobility due to pseudoarthrosis. Forced plantar flexion acquisitions are particularly useful in this condition because they can demonstrate the mechanism of injury.

Adult↗
PubMedDate not supplied

[Sportsman hindfoot pain: role of magnetic resonance imaging].

PURPOSE: To assess the outcome of Magnetic Resonance Imaging (MRI) in the diagnosis of sportsman hindfoot pain. MATERIALS AND METHODS: Fortythree professional athletes (31 men, 12 women, age range: 17-37 years) affected by hindfoot pain underwent MRI. Spin echo (SE) T1W, Gradient echo (GE) T2*W, and fat suppression (Short Time Inversion Recovery: STIR) images were acquired with a 0.5 T superconductive unit (Vectra, GE Medical System, Milwaukee, WI, USA). A dedicated extremities transmitter/receiver coil was used. The lesion site, the presence of anatomic variants (os trigonum, Haglund's deformity), and signal intensity changes were evaluated. RESULTS: In all cases MRI allowed the identification of the cause of the hindfoot pain, in relation to soft tissue (bursae, synovial or nervous structures), bone and articular diseases. Particularly, as regards soft tissue diseases, tendinous abnormalities and inflammatory bursal involvement were frequently found (77% of cases). Bone diseases (22% of cases with posterior talalgia alone), mostly involved the heel (60%), whereas cartilagineous diseases were present in 9% of cases. In 60% of cases an intra-articular osseous or cartilagineous displaced fragment coexisted, determinating joint locking during foot flexo-extension movements. In 38% of cases contemporary involvement of different articular structures was observed. DISCUSSION: Both MRI high contrast resolution and multiplanar capabilities allow the complete evaluation of hindfoot region. In our experience sagittal and axial planes were particularly well suited for the diagnosis and the assessment of disease extension. Furthermore, T2W (GET2*) and fat suppression (STIR) images allow high sensitivity even in early disease detection, when hyperemia or fluid collection occur. CONCLUSIONS: According to our results, it seems possible to state that nowadays MRI is the most reliable technique for identifying the causes of hindfoot pain, in order to provide a correct and effective pre-therapeutic planning.

Adolescent↗
PubMedDate not supplied

Pigmented villonodular synovitis of the foot: MR findings.

PURPOSE: To evaluate the MRI findings in the various forms of pigmented villonodular synovitis (PVNS) of the foot. MATERIALS AND METHODS: Seven hundred and fifty-three MR studies of the foot performed at our institute between June 1994 and April 2000 were retrospectively reviewed for the presence of PVNS. Spin echo (SE) T1W, Gradient echo (GE) T2*W, and fat suppression (Short Time Inversion Recovery: STIR) images were acquired with a 0.5 T superconductive unit (Vectra, GE Medical System, Milwaukee, WI, USA) provided with a dedicated transmitter/receiver coil. The site and type of lesions, the signal intensity patterns, and the presence of associated changes were evaluated. RESULTS: On the basis of the MR images and the above parameters, six patients (3 men, 3 women, age range: 35-48 years) with PVNS were selected. Three out of six PVNS were nodular, whereas the remaining three were diffuse. Of the three nodular forms, one was found in the sub-talar joint and the remaining two antero-medially to the talus. Instead, all of the diffuse lesions were located on the metatarsus. Perilesional oedema was seen in all cases, although more obvious in the nodular forms, whereas bone involvement (osteochondral erosion) was observed only in the diffuse metatarsal PVNS. Intra-articular bloody effusion was never observed. The MRI findings were confirmed by surgery in all cases. DISCUSSION: The high contrast resolution and multiplanar capabilities of MRI allow the complete evaluation of the structures of the foot affected by PVNS, and of the extent of soft tissue (bursae, synovial or nervous structures), bone and articular involvement. Although not specific, the presence of haemosiderin results in characteristic MR findings, due to the shortening of both T1 and T2 relaxation times. GET2* images are particularly well suited to this PURPOSE: Furthermore, in our experience, FIR images added better depiction of associated swelling. CONCLUSIONS: According to our results, MRI is now the most reliable technique for identifying and classifying PVNS, and allows correct treatment planning and effective monitoring.

Adult↗
PubMedDate not supplied

[Magnetic resonance in the study of tubercular coxitis].

The hip joint is the most common skeletal site for tuberculous disease, aside from vertebrae. Eight patients underwent MR investigations. In four cases (group A) there was suspicion of hip tuberculosis on the basis of clinical and laboratory findings, whereas the other 4 patients (group B) were known to suffer from hip tuberculosis. In group A, MRI always demonstrated inflammatory joint effusions, capsular distension, and subchondral bone conditions. No changes in the synovial membrane were found at onset, while the correct evaluation of the articular cartilage was not possible, due to the presence of concomitant effusion. In group B, MRI yielded no additional diagnostic information with respect to plain film, whereas it was undoubtedly the best diagnostic technique to detect joint effusions and to exclude other concomitant pathologic conditions such as neuroalgodystrophy and osteonecrosis. In conclusion, MRI does not yield specific or peculiar semeiological elements for the diagnosis of hip tuberculosis. On the other hand, MRI, together with clinics and with laboratory findings, allows the early and aspecific diagnosis of hip pain to be confirmed and specified, for the technique is a sensitive indicator of the presence of early lesions.

Adult↗
PubMedDate not supplied

Diagnostic accuracy of 16-row multislice CT angiography in the evaluation of coronary segments.

PURPOSE: To evaluate the diagnostic accuracy of 16-row multislice spiral computed tomography coronary angiography (16-MSCT-CA) for the non-invasive assessment of significant coronary artery stenosis. MATERIALS AND METHODS: We enrolled 40 patients (36 male, aged 59+/-11 yrs) with suspected obstructive coronary artery disease and a heart rate <65 bpm during the scan. The 16-MSCT-CA (Sensation 16, Siemens, Forchheim, Germany) was performed with electrocardiographically-gated technique after the intravenous administration of 100 ml of iodinated contrast material followed by a saline bolus chaser. The scan parameters were: collimation 16 x 0.75 mm, rotation time 0.42 s, feed/rot. 3 mm (pitch 0.25), 120 kVp, 500 mAs. All coronary segments = or >2 mm in diameter were evaluated by two independent observers for the presence of significant coronary artery stenosis (= or >50%). Consensus reading was compared to quantitative coronary angiography. RESULTS: The average heart rate was 55+/-6 bpm. Of the 428 segments of = or >2.0 mm diameter 92 were significantly diseased. Without exclusion of any branches (428), the sensitivity, specificity, positive, and negative predictive values to identify = or >50% obstructed segments were 95.7% (88/92), 95.8% (322/336), 86.3% (88/102), and 98.8% (322/326), respectively. No occluded left main, left anterior descending, circumflex or right coronary artery segments remained undetected. CONCLUSIONS: 16-MSCT-CA in a selected low-heart-rate patient population provides high diagnostic accuracy in the evaluation of significant coronary artery stenosis.

Contrast Media↗
PubMedDate not supplied

Non-invasive assessment of coronary artery stent patency with multislice CT: preliminary experience.

PURPOSE: To evaluate the diagnostic accuracy of multislice computed tomography coronary angiography (MSCT-CA) in the detection of in-stent restenosis. MATERIALS AND METHODS: Forty-two patients (33 male, 9 female, mean age 58+/-8 years) previously subjected to percutaneous implantation of coronary stent with suspected in-stent restenosis, underwent a 16-row MSCT (Sensation 16, Siemens) examination. The average time between stent implantation and MSCT-CA was 7.4+/-5.3 months. The following scan parameters were used: collimation 16x0.75 mm, rotation time 0.42 s, feed 3.0 mm/rot., kV 120, mAs 500. After administration of iodinated contrast material (Iomeprol 400 mgI/ml, 100 ml at 4 ml/s) and bolus chaser (40 ml of saline at 4 ml/s) the scan was completed in <20 s. All segments with a stent were assessed by two observers in consensus and were graded according to the following scheme: patent stent, in-stent intimal hyperplasia (IIH) (lumen reduction <50%), in-stent restenosis (ISR) (=/>50%), in-stent occlusion (ISO) (100%). Consensus reading was compared with coronary angiography. RESULTS: Forty-seven stents were assessed (16 in the right coronary artery; 4 in the left main; 22 in the left anterior descending; 5 in the circumflex). In 7 (17%) stents there was ISR (3) or ISO (4), and in 4 (10%) stents there was IIH. The sensitivity and negative predictive values for the detection of ISO were 80% and 98%, respectively, while for the detection of ISR+ISO they were 50% and 89%, respectively. CONCLUSIONS: Although the results are encouraging, the follow-up of stent patency with MSCT-CA does not show a diagnostic accuracy suitable for clinical implementation.

Journal Article↗
PubMedDate not supplied

The Color Doppler with contrast agent US in the study of post Cholecistectomy Syndrome.

PURPOSE: The aim of this study was to evaluate the study of intra- and extra-biliary ducts by contrast-enhanced colour-Doppler in patients who have undergone laparoscopic cholecystectomy. MATERIALS AND METHODS: Contrast-enhanced colour-Doppler US was performed in 15 patients who had undegone laparoscopic cholecystectomy. The US contrast agent was introducted into the Kehr or Pedinelli tube to allow visualisation of the bile ducts and duodenum. RESULTS: The colour-Doppler study enabled visualisation of the contrat agent in the intra- and extra-hepatic bile ducts and in the duodenum in all patients, thereby permitting the accurate study of the post-operative course. The data obtained were confirmed by conventional radiology. CONCLUSIONS: The advantages of this US ultrasound technique are the complete absence of ionising radiation and no intolerance to the US contrast agent. This technique could therefore be used in selected patients as an alternative to trans-Kehr and trans-Pedinelli cholangyography.

Journal Article↗
PubMedDate not supplied

MR findings in lipoma arborescens of the knee: our experience.

PURPOSE: This paper describes the role of MR imaging in the identification of the different macroscopic patterns of lipoma arborescens. MATERIALS AND METHODS: Between June 1995 and January 2004, a total of 6387 MR examinations of the knee were retrospectively assessed for the presence of lipoma arborescens. The MR examinations were performed using a superconductive 0.5 T MR unit with a transmitting/ receiving coil dedicated for the extremities. The MR images were acquired with SE T1-weighted, GE T2-weighted and STIR sequences in sagittal, coronal and axial planes with 3-mm thickness and 1-mm gap. RESULTS: Lipoma arborescens was identified in 9 patients (mean age: 36 years). In 2/9 cases a localized lipoma arborescens was detected as a well-marginated single nodule on the suprapatellar bursa without irregularity or synovial hyperplasia. In the remaining 7 cases diffuse lipoma arborescens was identified on the wall of the suprapatellar bursa. In one case of diffuse lipoma arborescens there was involvement of both knees. In all cases the MR findings were verified at surgery and the final diagnosis was made by histological examination. CONCLUSIONS: MR imaging shows a high accuracy in the identification and characterization of lipoma arborescens, due to its multiplanar capabilities and high contrast resolution. MRI allows correct evaluation of size and grade, accurate treatment planning and effective follow-up, avoiding the need for synovial biopsy.

Journal Article↗
PubMedDate not supplied

[Ultrasound-guided percutaneous injection of ethanol in Plummer's adenoma. Our experience with 8 patients].

The authors report their experience in the study of 8 patients showing symptoms of thyroid hyperfunction (Plummer's adenoma) and treated with US-guided percutaneous ethanol injection. The treatment consisted in injecting sterile ethanol in varying amounts (2 to 5 ml) according to nodule size, using a fine needle under US guidance. The patients underwent 3 to 6 injections, according to biochemical (T3-T4-TSH) and scintigraphic findings. Follow-up at 12 months showed regression of clinical symptoms, a trend of hormone levels toward normalization and recovery of previously suppressed parenchymal function. No significant complications were observed, except for a transient thyrotoxic crisis in the patient bearing the largest nodule. The treatment of Plummer's adenoma by means of percutaneous ethanol injection under US guidance appears to provide specific clinical and technical advantages over other conventional treatments.

Adenoma↗
PubMedDate not supplied

[Achilles tendon disease in athletes. An ultrasonographic study with a 13-MHz probe].

The authors investigated the diagnostic potentials of 13-MHz small parts probes in identifying inflammatory and degenerative disorders of the Achilles tendon in 63 athletes (middle-distance runners) of both sexes, aged 16 to 32 years. The patients were divided into four groups and examined with 13-MHz sectorial probes to assess the comparative reliability of the former probe versus a 7.5-MHz linear probe. US examinations with the 13-MHz probe allowed early structure changes which had been missed with the 7.5 MHz probe to be demonstrated in 10 of 17 subjects in the control group. Patients in groups 2 and 3, with severe changes in tendon structure, had the same findings with the two probes relative to identification and framing of degenerative conditions. In 3 patients submitted to surgical follow-up (group 4), the 13-MHz probe allowed good demonstration of the repairing processes, consisting of gross hyperechoic areas and hypoechoic masses with blurred edges. In conclusion, the use of a 13-MHz probe may not be considered an alternative to that of a 7.5-MHz probe. Nevertheless, higher-frequency probes provide useful information in the early phase of structural injury, when no clinical correlations are found and US with conventional probes fails to provide adequate information.

Achilles Tendon↗
PubMedDate not supplied

[Chronic osteomyelitis of the long bones: magnetic resonance imaging].

To investigate MR capabilities in assessing the extent of disease in chronic osteomyelitis of long bones, we examined 6 consecutive patients, 4 men and 2 women (age range: 27-67 years; mean: 42 years), with posttraumatic chronic osteomyelitis diagnosed at clinics, US, CT and radiography. The diagnosis had surgical or bioptical confirmation. MR studies were performed with an 0.5 T superconducting magnet, a surface coil and T1-weighted SE sequences-before and after Gd-DTPA administration-STIR and T2-weighted SE sequences, on the axial and coronal or sagittal planes. The signal intensity of the inflammation area was hypointense on short TR and TE images and hyperintense on long TR and TE images. After Gd-DTPA administration, granulation tissue surrounding the infection was enhanced in all cases and also the areas of vascularized inflammation within bone marrow were enhanced in two cases. MRI provided accurate and detailed information as to soft tissue and medullary canal involvement depicted sinus tracts in 5 cases and confirmed the presence of sequestrum in 5 cases, in agreement with previous CT findings. In our experience, MRI proved to be a reliable tool to assess the intramedullary and extracompartmental extent of osteomyelitis and also to plan surgery. MR specificity, which is often affected by post-traumatic or postoperative changes, improves markedly if some morphological features typical of the condition are also considered, such as sequestrum and sinus tracts.

Adult↗
PubMedDate not supplied

MR imaging technique for the diagnosis of pituitary iron overload in patients with transfusion-dependent beta-thalassemia major.

To identify the optimal MR imaging technique for diagnosing pituitary iron overload, we compared spin-echo and gradient-echo MR imaging with measurements of pituitary T2 relaxation times in 30 patients with secondary hemochromatosis due to transfusion-dependent beta-thalassemia major and in 10 healthy volunteers. We found that the optimal MR imaging technique to evaluate pituitary iron overload is the gradient-echo T2*-weighted technique, as it best demonstrated signal reduction in the anterior lobe of the pituitary gland.

Adolescent↗