Biomedical subjects

M Pedrazzini

Publications and source records attributed to M Pedrazzini.

13 recordsLinked to original sources

PubMed2000

[Tridimensional (3D) reconstruction in the osteoarticular area].

Three-dimensional reconstruction techniques have been used since the development of computed tomography. In skeletal radiology they have been used to better visualize fractures and spatial relationships between fragments in maxillo-facial surgery. Aim of this paper is to illustrate the most important reconstruction techniques and their application in skeletal radiology. Images can be obtained by means of a Spiral CT scanner with the following parameters: collimation/pitch/reconstruction interval 2/1/1. Acquired images are sent to a workstation with a software running on a Window NT platform Vitrea 2.01 (Vital Images, USA) equipped with Volume Rendering algorithm. SSD as well as MPR and curved reformatted reconstruction algorithms is available at the CT console. Three-dimensional reconstruction have been shown to be useful for the diagnosis and for a preoperative planning. Other applications of three-dimensional reconstruction techniques are prosthesis engineering and biomechanic research. 3D images help the communication between radiologist and surgeons. Technical advances in acquisition methods and in reconstruction algorithms are needed to improve image quality and use in skeletal radiology.

Arthrography↗

PubMed2000

[Rotator cuff rupture. Diagnostic imaging].

Conventional radiography, ultrasound, Magnetic Resonance (MR), Arthrography Computed Tomography (Arthro-CT) and Arthrography Magnetic Resonance (Arthro-MR) are available for diagnosis of rotator cuff tears. Our purpose is to assess the specificity and sensitivity of these examinations and if they could give to the surgeon all the informations to select the more accurate treatment. We have evaluated retrospectively the images of 68 patients, 43 male and 25 female (average age 51 years), which then have been surgically treated for rotator cuff pathology. On the basis of our findings, we think that conventional radiography and ultrasound are excellent in a first evaluation. MR images, particularly in the coronal and sagittal oblique planes, are able to demonstrate partial or complete rotator cuff tears. The use of intra-articular contrast medium (arthro-CT, arthro-MR) should be reserved for partial lesions on specific cases.

Adult↗

PubMed2000

[Shoulder instability: diagnostic imaging].

Shoulder instability is often diagnosed among athletes; two clinical forms are distinguished: anatomical instability, with recurrent luxation of the shoulder, and functional instability, with pain, articular "click" and sensation of instability. Lesions of periarticular soft tissues (capsula, fibrocartilaginous labrum, gleno-humeral ligaments and rotator cuff) are common in both forms, while lesions of bone structures (humeral head and glenoid of scapula) are typical of shoulder with previous dislocation. Purpose of our retrospective study was to verify the value of magnetic resonance (MRI) and computed arthrography (arthro-CT) in diagnosing these lesions in 57 patients suffering from shoulder instability. On the basis of our results and experience we think that in a preoperative evaluation of an unstable shoulder, arthro-CT and arthro-MRI are more accurate because the intra-articular injection of a contrast medium better identifies lesions of capsula, gleno-humeral ligaments and fibrocartilaginous labrum. In other circumstances, such as the study of the shoulder for legal purposes, MRI is preferable because it offers an accurate and global evaluation of periarticular structures.

Adolescent↗

PubMed2000

[Shoulder diseases in throwing athletes: radiologic assessment and surgical correlation].

Lesions of the shoulder, especially rotator cuff tears and glenoid labrum (SLAP) lesions, are commonly caused by traumatic episodes in athletes such as repeated trauma from throwing. The available radiological methods are MRI, CT and MR arthrography. Twelve athletes suffering from shoulder pain or instability have been studied and then underwent successful treatment in arthroscopy. On the basis of our results and experience, we think that MR, especially with intra-articular injection of contrast medium, is the best examination because it offers an accurate evaluation of both rotator cuff and glenoid labrum. Nevertheless difficulties are often encountered and definitive diagnosis sometime rests on arthroscopic exploration.

Adolescent↗

PubMed2000

[Wrist trauma: diagnostic imaging].

Wrist injury is common throughout life and, although history and physical examination provide important information regarding the type of lesion, a radiological study is essential to determine a specific diagnosis. Conventional radiography plays a central role in the wrist injuries but the diffusion of more sensitive methodics offers new possibilities. Our purpose is to evaluate the role of computed tomography (CT), magnetic resonance (MR) and arthrography in wrist trauma. We retrospectively examined the images of 45 patients with wrist injuries: in every patients a radiological examination in 4 standard projections was executed while in 25, 9 and 11 patients CT,MR and arthrography were performed. On the basis of our findings we think that conventional radiography is often sufficient for diagnosis of bone lesions even if CT sometimes is required to detect subtle fractures. MR has an high sensitivity not only for abnormalities of soft tissues, including interosseous ligaments and triangular fibrocartilage, but also bony abnormalities such as occult fractures and early osteonecrosis. Arthrography still remains the best procedure for evaluating lesions of triangular fibrocartilage and intercarpal ligaments especially in a preoperative phase.

Adolescent↗

PubMed2000

[Injuries of the cruciate ligament of the knee: diagnostic contribution of MR and spiral CT].

Lesions of cruciate ligament are common after knee trauma of different degree of gravity. Lesions evaluation is possible thanks to CT and MRI. Our purpose is to verify their value in diagnosis of cruciate ligaments lesions. We retrospectively evaluated 160 patients (80 CT and 80 MRI) with subsequent diagnosis of cruciate ligaments injury. CT and MRI were performed in the acute phase and in the subacute phase within 2-3 weeks from trauma. On the basis of our results CT and MRI shown a reduced sensitivity in acute phase owing to the intraarticular haemorrhage; in this phase MRI gives more information about fibres interruption. In subacute or chronic phase, both methods are correct in recognising the lesions but MRI is more sensitive and accurate. It is a real wish that, with more MRI machines diffusion, this method will be preferred in the study of cruciate ligaments both in acute phase and subacute-chronic phase.

Adolescent↗

PubMed2000

[Meniscal injuries of the knee. Diagnostic imaging].

Nowadays, treatment of meniscal tears is conservative with removal only of the broken part of meniscus. For this reason, before arthroscopy, the orthopaedic surgeon needs for an accurate preoperative diagnosis that could be obtained with computed tomography (CT) and magnetic resonance (MR). Our purpose is to value the actual role of CT and MR in diagnosis of meniscal tears. We retrospectively evaluated CT and MR images of 128 patients (average age 32 years) who then underwent arthroscopy. On the basis of our findings CT and MR have been shown to be very accurate to detect meniscal tears, even if with both methodics false positives and false negatives are possible. Nevertheless, MR is able to give high resolution multiplanar images without using ionising radiations and is preferable because of its high accuracy in recognising associated lesions of ligaments or articular cartilage.

Adolescent↗

PubMed2000

[Femoro-patellar instability: radiologic assessment].

To propose a simple and reproducible radiological evaluation of the patellofemoral instability that enables the orthopaedic in choosing the best therapy. The radiographs and CT examinations of 55 patients, 38 female and 17 male (range 18-32 years) have been evaluated retrospectively. Twenty-height of them underwent surgical treatment for patellar instability. A radiological protocol which includes conventional radiographs in two projections and a CT examination both in extension, with and without quadriceps contraction, and in flexion at 20 degrees allows to give all the informations one's need for evaluating patellar height and mobility, trochlear dysplasia, valgism of the knee and the degree of excessive lateral position of the anterior tibial tuberosity. It's a simple, quick, accurate and reproducible protocol to do, even with different radiological systems.

Adolescent↗

PubMed2000

[Spiral CT and MR in injuries of the ankle and the foot].

Conventional radiography is the first radiological examination in injuries of ankle and foot, but often it has normal findings or it is difficult to execute for critical conditions of patients. Our purpose was to assess the value of CT and MRI in injuries of ankle and foot; we retrospectively reviewed the MR and CT images from 48 patients (age range 18-55 years), whose 16 had a major trauma with other skeletal segment lesions and the remaining a minor trauma limited to ankle and foot. On the basis of our results and experience, we think that in major trauma CT and MRI have similar findings about preoperative evaluation of fractures even if MR better identifies ischemia of fragments, subcortical contusions and lesions of ligaments, capsula or tendons. In minor trauma, MR is superior to CT because it can diagnose lesions of bone and periarticular structures that are difficult or impossible to identify with other instrumental examinations.

Adolescent↗

PubMed2000

[Spiral CT in maxillo-facial trauma].

Fractures of facial skeleton are common in a busy emergency department in often requires careful radiological study before surgical treatment. Radiographic evaluation of facial injuries is especially challenging because the complex facial structure results in a confusing overlapping of densities on the radiograph. Instead Spiral-CT enables obtaining images on different planes so that even subtle or complex fractures may be evaluated in the best way. Moreover, associated lesions of important organs can be diagnosed. Our purpose is to verify the value of Spiral-CT in traumatology of facial skeleton. We have evaluated retrospectively the images of 82 patients admitted for facial trauma. On the basis of our findings we think that conventional radiography should be reserved only for light traumas of superficial structures (nose, zygomatic arch, body of jaw); in the remaining cases Spiral-CT should be the first radiological examination.

Adolescent↗

PubMed2000

[Cervical spine injuries: diagnostic imaging].

In past few years, traumas of cervical spine have increased, chiefly owing to rise of road accidents. Nevertheless, only in a small percentage of cases lesions of cervical spine occur and, in order to reduce many negative radiographs, a careful clinical examination is required. Our purpose is to verify the value of radiology in evaluation of acute trauma of cervical spine and to propose an adequate radiological protocol. In the course of two years (1998-99), 376 patients were admitted in consequence of cervical trauma of different degree of gravity. In all patients, conventional radiographs were obtained, in 93 a computed tomography (CT) examination was executed and only in 18 patients with neurological symptoms a magnetic resonance (MR) was required. Fractures of cervical spine wee identified in 91 cases and in patients in which MR images were obtained, neurological lesions of various severity were diagnosed. On the basis of our results, we think that, in a clinical suspicion of cervical spine lesions, a conventional radiographic study has first to be performed even if often good radiographs aren't obtained for technical difficulties. If doubts persist on conventional radiographs or a fractures has already been diagnosed on radiographs but we want to verify its stability, a CT needs to be performed. MR is required if neurological symptoms are present in order to diagnose lesions of spinal marrow, nerve roots or ligaments.

Adolescent↗

PubMedDate not supplied

Duodenal hemangiopericytoma: CT and MRI findings.

Hemangiopericytoma (HPC) is a rare mesenchymal tumor generally occurring in adults and originating from the pericytes. The tumor more commonly affects the soft tissues of the extremities, the pelvis, and the retroperitoneum. We describe the computed tomographic and magnetic resonance appearance of a patient affected by HPC of the duodenum.

Aged↗

PubMedDate not supplied

[Radiologic assessment of femoro-patellar instability. Personal experience and review of the literature].

PURPOSE: To propose a simple and reproducible radiological evaluation of patellofemoral instability to enable the orthopaedic surgeon to choose the best therapy. MATERIAL AND METHODS: We have evaluated retrospectively the radiographs and CT examinations of 25 patients, 15 female and 10 male, aged between 18 and 32 years. They underwent surgical treatment for patellar instability in the past 4 years. Lateral retinacular release has been performed in every patient, medial transposition of the anterior tibial tuberosity has been performed in 23 patients and in 5 of them also its distal replacement, proximal Insall's realignement was performed in 20 cases and only 1 patient underwent trochleoplasy. Preoperative conventional radiographs included antero-posterior view, true lateral view (exact superimposition of the posterior trochlear edges) and axial views at 30 degrees of knee flexion. On lateral view, the patellar height was evaluated based on Caton-Deshamps index and trochlear dysplasia assessed using the methods suggested by Dejour. A CT examination of both knees was performed: the images were taken first with knees in extension, with and without quadriceps contraction, then in flexion at 20 degrees. Patellar "bascùle" angles were measured both with quadriceps relaxed and contracted as an index of quadriceps dysplasia; the TAGT in extension was evaluated as an index of the degree of lateral position of the anterior tibial tuberosity. Preoperative conventional and CT findings were compared with those obtained postoperatively at 30.4 months from the surgical intervention. RESULTS: All patients were free from complaints after surgery. In 5 patients a high patella was corrected by distal realignement of anterior tibial tuberosity. A trochlear dysplasia with different degrees of severity was present in all cases and it was not modified by surgical treatment, with the exception of the patient who underwent trochleoplasty. In the 20 patients who underwent proximal Insall's realignment, patellar "bascùle" angles--pathological before surgery--were restored to normal values with the exception of 3 cases. In 23 patients who underwent medial transposition of anterior tibial tuberosity, the values of the TAGT were all normalized: nevertheless, in three patients low values of the TAGT were found after surgery and this condition may predispose to the development of medial patellofemoral by iperpression syndrome. CONCLUSIONS: In patients suffering from patellofemoral instability, a radiological protocol which includes conventional radiographs in two projections and a CT examination both in extension, with and without quadriceps contraction, and in flexion at 20 degrees supplies all the information needed for evaluating patellar height and mobility, trochlear dysplasia, valgism of the knee and the degree of excessive lateral position of the anterior tibial tuberosity. Careful evaluation of such abnormalities is important for selecting the best surgical treatment for each patient. It's a simple, quick, and accurate protocol that may be reproduced, even using different radiographic equipment. The collaboration between the radiologist and the orthopaedic surgeon is crucial for the correct interpretation of radiological findings, which must be evaluated together with clinical findings so that an adequate therapeutical plan could be proposed.

Adolescent↗