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M De Maria

Publications and source records attributed to M De Maria.

67 records · Page 4Linked 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

Intra-articular osteoid osteoma: diagnostic imaging in three cases.

PURPOSE: To report our experience pertaining to three cases of intra-articular osteoid osteoma assessed by means of integrated imaging and review of literature. MATERIALS AND METHODS: Medical records, radiologic and nuclear medicine findings pertaining to three cases of intra-articular osteoid osteoma were retrospectively evaluated and compared with those of surgery. All the patients (2 males, one female; age range 8-38 ys) affected by intra-articular osteoid osteoma respectively of the elbow, tibio-talar joint and hip were evaluated by means of radiographic examination and Magnetic Resonance Imaging (MRI). SE T1-w and T2-w, GRE T2*-w, GRE 3D T1-w and STIR pulse sequences were used and axial, coronal and sagittal images were acquired. Two patients underwent CT scan. One patient underwent skeletal scintigraphy. All the patients underwent surgery. RESULTS: In 2 out of 3 cases plain radiography allowed the radiologist to suspect the presence of the lesion. In the remaining one, plain radiography failed to detect both the nidus and the perilesional osteosclerosis; nevertheless, a small osteochondral erosion of the humeral condyle suggested the presence of joint inflammation, thus leading to further investigation. CT scan well depicted the presence of the nidus and, in one case, the presence of joint effusion. MRI was always able to detect the nidus, which presented as lesion of low to intermediate signal in T1-w images, low signal in the T2-w images in one patient and high signal in the remaining two; in these latter STIR images showed high intensity nidus and edema of neighbouring cancellous bone. Furthermore, in all patients MRI clearly depicted joint effusion. Skeletal scintigraphy demonstrated both the lesion and the inflammatory involvement of neighbouring soft tissue. In all patients histologic specimen confirmed the diagnosis of osteoid osteoma with joint inflammation and synovitis. CONCLUSIONS: According to our results and literature data the pre-surgical diagnosis of osteoid osteoma is very difficult to achieve. Indeed, only the combination of clinical information and radiologic and nuclear medicine findings enables the radiologist to make the right diagnosis.

Adolescent↗
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

[Experimental studies on possible biological effects of ultrasonic diagnosis: ultrastructural analysis of rat embryo].

Within the limits of a systematic research on the biological effects of the ultrasounds, the authors refer on their personal experience on rat's embrions treated, for 120 seconds, with a ultrasonic beam having the common characteristics used in diagnostic investigations. The ultra-structural studies on the hepatic parenchyma substantially confirm the previous results obtained in the adult cavy, exposed for the same period of time, i.e. a diffuse cytoplasmic vacuolization and an unstable mitochondrial damage. Various suggestions are advanced on the particular sensibility that the mitocondria show because of the ultrasonic action. The authors explain the limits of their experimentation in this specific sector of the scientific research.

Animals↗
PubMedDate not supplied

[Echography, magnetic resonance and double-contrast arthrography of the rotator cuff. A prospective study in 30 patients].

Shoulder pain is a common clinical problem with different etiologies. Without a specific diagnosis, treatment could be ineffective, causing functional limitation, chronic pain and atrophy. US and MRI allow in many cases to correctly define the different etiologies causing shoulder pain, often due to rotator cuff conditions. From June to September 1992, thirty patients with clinically suspected acute or chronic rotator cuff lesion were studied with US, MRI and double contrast arthrography. US and MRI findings were evaluated and compared using arthrography and surgery as the gold standard. The overall accuracy of MRI was 93%: the method yielded accurate information about size and number of rotator cuff tears, and about bursal, bone and muscle involvement. US accuracy was 83% in the diagnosis of large tears, 63% in the diagnosis of small and partial tears and only 11% in the diagnosis of tendinitis. Both MRI and arthrography exhibited high accuracy (respectively 91 and 100%) in the detection of rotator cuff tears when their results were compared with surgical findings. A flow chart to be used in the patients with acute or chronic shoulder pain was drawn from the critical analysis of the above results.

Arthrography↗
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

[Value of magnetic resonance in the diagnostic definition of neurotoxoplasmosis and in the assessment of the response to pharmacological treatment].

PURPOSE: We investigated the role of Magnetic Resonance Imaging (MRI) in the diagnosis of neurotoxoplasmosis and in the evaluation of drug treatment response. MATERIAL AND METHODS: Twenty-six AIDS patients (22 men and 4 women, mean age 26.7 years) with clinical suspicion of neurotoxoplasmosis were examined. A patient was considered to have neurotoxoplasmosis if there were signs of focal neurologic impairment and a positive/questionable response to the serum test for Toxoplasma gondii. MR images were acquired with T1-weighted spin-echo (SE) and inversion recovery (IR) sequences and with T2-weighted SE sequences. Gd-DTPA was administered in all cases. After the beginning of therapy with sulfadiazine and pyrimethamine all patients were submitted to clinical and neuroradiologic follow-up for 60 days. RESULTS: MR examinations on admission demonstrated at least one brain lesion in all patients and multifocal involvement in 70% of cases. Enhancing lesions were found in 90% of patients (83% ring enhancement, 4% focal enhancement, 3% mixed patterns). The most frequent lesion sites were the basal ganglia and thalami (70%). The brain lesions were subdivided into 4 groups by their morphology and signal patterns. DISCUSSION: The time course of clinical and neuroradiologic responses demonstrates a rapid improvement after the first week of therapy, which stabilized after the second week. Pearson correlation between clinical and neuroradiologic treatment responses showed a nearly linear correlation (r = .97; p < .001). The diagnosis was then confirmed in all patients based on the positive response to the serum test for Toxoplasma gondii (IgG > 12 UI/mL) and/or clinical and neuroradiologic improvement after therapy. DISCUSSION AND CONCLUSIONS: This study demonstrates the accuracy of MRI in the detection of toxoplasmosis brain lesions and in the evaluation of treatment response.

AIDS-Related Opportunistic Infections↗