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M Midiri

Publications and source records attributed to M Midiri.

At least 73 records · Page 4Linked to original sources
PubMed1997

[Biomechanics and semiology of transient lateral patellar dislocation: reliability of magnetic resonance diagnosis].

Transient patellar dislocation is a rare finding. It is usually due to direct trauma in mediolateral direction or to indirect trauma related to violent quadriceps muscle contraction. The clinical diagnosis of transient forms is usually rather difficult because the associated signs (hemarthros and pain at the joint and/or at the vastus medialis insertion) are not specific. Conventional radiography and CT are very accurate in bone studies, but exhibit major limitations in the detection of capsular injuries with intramedullary and/or cartilaginous bone involvement. We investigated MR diagnostic reliability in the study of the injuries caused by transient patellar dislocation. 526 MR examinations of the knee were reviewed retrospectively; fifteen of them were positive for transient patellar dislocation. We used a .5 T superconductive MR unit with a circumferential extremity coil. Axial, coronal and sagittal T1-weighted spin echo, T2*-weighted gradient echo and axial STIR images were acquired. The following criteria were considered specific for the diagnosis of former lateral patellar dislocation: retinacular changes; patella site; signal intensity changes in femoral and patellar intramedullary bone; joint effusion; cartilage and subchondral bone changes. All the patients with transient patellar dislocation had hemarthros with inner retinaculum involvement. The femoropatellar joint was incongruous in 115 cases; patellar subluxation was external in 8/11 patients and lateral in the remaining 3 patients. Medullary bruises were found in 8/15 cases and cartilage injuries in 13/15. Finally, other joint components, such as the posterior horn of the medial meniscus or the anterior cruciate ligament were involved in 6/13 cases. Arthroscopy was performed in 6 patients with associated injuries and confirmed all MR findings (100% agreement). To conclude, in our experience MRI was a very reliable tool to study the injuries due to transient patellar dislocation because it showed specific changes and possible associated traumas, which helps choose the most suitable treatment.

Adolescent↗
PubMed1997

[Potential uses of color Doppler in periskeletal soft tissue neoplasms].

Integrated imaging plays a fundamental role in the study of periskeletal soft tissue tumors, for both diagnosis and treatment planning. The steady and progressive technologic progress of color Doppler US equipment now permits the integration of conventional morphostructural parameters with the biofunctional data of lesion flow patterns and relative qualitative features. To assess color Doppler capabilities in differentiating benign from malignant soft tissue tumors, we reviewed the B-mode and color Doppler findings of 43 consecutive patients with a palpable periskeletal soft tissue mass. All patients were examined with a real time unit (Ultramark 9 HDI), with a broadband (5-10 MHz) linear transducer operating at 6.5 MHz for Doppler measurements. The PRF was set at 1500 to 800 Hz with 70% color gain; a 100 Hz wall filter was used. We kept the color box in the area of interest as small as possible to keep the frame rate high; pulsed Doppler studies were performed with a small sample volume and 2000 Hz PRF. The following signs were considered: morphostructural features; the presence/absence of color signals; the (peripheral/internal) site of vascular branches, their caliber and course; the number of afferent vascular poles; resistance index. As a rule, malignant masses tend to differ from benign masses for the presence of multiple vascular afferent branches, especially if they have an irregular pattern and caliber, and for the variability of the resistance index measured in different parts of the same mass. Further examinations, performed with second level imaging (CT and MRI) and microhistologic tests, respectively after biopsy and surgical resection, confirmed the high predictive value of color Doppler US, with only 1 false negative and 2 false positives; color Doppler sensitivity and specificity were 94.7% and 91.6%, respectively, which are higher values than those obtained with US alone (63% and 66.6%). Therefore, we believe that color Doppler US can be systematically applied to the study of periskeletal soft tissue masses, integrating conventional US for the correct selection of the patients to be submitted to second level investigations.

Adolescent↗
PubMed1996

[Stener lesions: ultrasonography assessment in 12 cases].

We investigated the ultrasonographic (US) features of Stener injury and thus the role of US in the diagnosis of this condition. Stener injuries are characterized by the tear of the cubital ligament system of the first metacarpophalangeal joint during hyperabduction. This condition may be associated with the displacement of the ligament proximal stump above the thumb adductor muscle. We examined 12 patients (9 men and 3 women) with a clinical diagnosis of joint instability due to hyperabduction of the first metacarpophalangeal joint. All the US exams were performed with a linear probe (7.5-10 MHz); a 13-MHz probe was also used in 7 patients. All the patients were submitted to radiography in the standard projections, to detect associated bone injuries. US allowed the identification of a round lesion surrounded by a hypoechoic halo, between the distal edge of the dorsal interosseous muscle of the first finger and the first metacarpal bone (the proper Stener injury) in 4/12 patients. In contrast, no typical sign was shown in the other 8 patients. US results were then compared with surgical findings. The diagnosis of proper Stener injury was surgically confirmed in 4 patients. Only 2 patients with clinical signs of thumb instability, who were negative for Stener injuries at US, were submitted to surgery which demonstrated the ligament tear responsible for joint instability, but ruled out the displacement. To conclude, US must be integrated with clinical signs because this imaging method accurately shows complete tears with displaced proximal stump of the cubital ligament.

Adult↗
PubMed1995

[Biomechanics and semeiotics of traumatic lesions of the posterior cruciate ligament using magnetic resonance].

The authors reviewed 458 MR examinations of the knee to assess the potentials of this technique in the study of traumatic injuries of the posterior cruciate ligament (PCL) and to investigate the frequency of their association with injuries of other knee joints. MR images were acquired with an 0.5-T super-conductive unit with an extremity coil. T1-weighted spin-echo (SE) and T2*-weighted gradient-echo (GE) sequences were used on sagittal, coronal and, in some cases, axial planes, with 3-mm slice thickness and 0-1 mm slice gap. The following parameters were studied to diagnose partial or complete PCL tears: PCL thickness and outline, disruption of ligamentous fasci and signal intensity features. The injuries were classified as proximal, intermediate and distal according to their site. Thirteen PCL tears were detected, 5 of them complete and 8 partial. Complete tears were found in 4/5 patients in the middle third and one patient had a distal intersection tear with tibial bone avulsion. Partial tears were found in the distal tract in 5/8 patients, in the proximal tract in one patient and in the middle third in 2 patients. In 12/13 patients capsuloligamentous knee tears were associated. Overall MR rate of PCL tears was 2.8%; of them, 92.3% were associated with other capsuloligamentous injuries. MR diagnosis was confirmed at arthroscopy in 12/13 patients. The sagittal plane was best in optimally demonstrating the whole PCL and its injuries. GE T2* sagittal sequences demonstrated the site of PCL tears better than SE sagittal ones. Relative to other authors, we found MRI an extremely reliable method to distinguish partial from complete PCL tears. This was probably due to the thinner slices (3 mm) we used. MRI can accurately assess the extent of traumatic injuries of the PCL and of other capsuloligamentous parts of the knee, which is relevant from the clinical point of view. Indeed, MRI allows useless diagnostic arthroscopy to be avoided and yields major indications to choose the correct treatment.

Adult↗
PubMed1995

[Aortic isthmic stenosis: clinical study and postoperative follow-up by MRI. Report of a case].

A case report. Nuclear Magnetic Resonance (NMR) is the most recent non-invasive diagnostic technique which can provide high quality anatomic and functional data. The absolute safety of the method make it suitable for follow-up of patients who have undergone aortic surgery. The authors report the case of a 12-year-old girl suffering from isthmic coarctation of the aorta for which both traditional methods (echocardiography and angiography) and NMR were used. Following bypass surgery with a dacron implant in the stenotic tract of the aorta, the patient was followed up using transthoracic echocardiogram and NMR. The latter method was found to be most efficacious in providing anatomic and functional information after surgery, enabling an optimal follow-up of these patients.

Angiography↗
PubMed1994

[Comparison of echography and magnetic resonance in sprains of the external compartment of the ankle].

In most cases ankle sprains involve external compartment ligaments. In particular, the anterior talofibular ligament is involved alone in 70% of cases and together with calcaneofibular and posterior talofibular ligaments in the remaining 30% of cases. To investigate the potentials and the possible limitations of high-frequency US (7.5-13 MHz) for the preliminary assessment of the extent of damage of the capsulo-ligamentous lesions of the external ankle compartment, 25 athletes with clinical diagnosis of sprain trauma were examined with conventional radiology. Morphology and structure were studied from the semiologic point of view. US findings were compared with MR results. In all patients, US showed anterior talofibular ligament lesions alone in 13 patients and associated with calcaneofibular ligament lesions in 12 patients. The posterior talofibular and the interosseous talocalcaneal ligaments were never demonstrated by US. In 4/13 patients diagnosed by US as having isolated anterior talofibular lesions, MRI demonstrated a coexisting calcaneofibular lesion (4/13) and, in one of them, a posterior talofibular and interosseous talocalcaneal ligaments lesion. The comparison of US and MR findings in the patients US had diagnosed as having associated anterior talofibular and calcaneofibular ligaments lesions, showed 100% agreement; MRI allowed the demonstration of the lesions in the posterior talofibular and interosseous talocalcaneal ligaments in 2/12 patients. Considering the statistical prevalence of the anterior peroneal-astragalic lesions caused by ankle sprains, the use of high-frequency US as the first diagnostic approach seems justified. Nevertheless, MRI is a fundamental complement for accurately assessing damage extent.

Adolescent↗
PubMed1994

[Laser-assisted angioplasty in chronic obliterative arteriopathies of the lower limbs. The authors' personal experience].

The laser represents one of the most interesting new methods of vascular surgery. As for laser-assisted angioplasty, the major clinical experience has come with Nd: Yag and Argon lasers. The authors comment on the 1989-1992 series of cases consisting of 51 arteries recanalized with a Nd:Yag laser--the patients were 42 men and 9 women, their mean age being 56.6 years. Four iliac obliterations, 36 femoropopliteal and 11 popliteotibial obliterations were treated surgically, according to the single anatomical radiologic circumstances. The immediate results showed 41 recanalizations (80.4%) 3 perforations (5.9%), 6 dissections (11.8%) and 2 distal emboli (3.9%). The long-term results, with a follow-up period ranging 6 months to 4 years (average: 1.8 years), were investigated with seriated c.w. Doppler, Doppler US and digital venous angiography and showed, in 34 examined patients, 22 patencies (64.7%), 8 stenoses > 50% (23.5%) and 3 occlusions (11.8%). These findings prove the value of laser-assisted--both percutaneous and surgical--angioplasty in the treatment of arterial occlusions both alone and combined with surgery. The results, whose positivity comes also from an eclectic interaction with surgery, and mostly from a systematic enhancement of the laser channel with balloon angioplasty, could be markedly improved upon by means of more selective and effective equipment.

Adult↗
PubMed1993

[The role of needle aspiration biopsy in the diagnosis of parotid masses].

The aim of this work is to assess the list of fine needle aspiration in the diagnosis of lesions of the parotid. Thirty-nine patients suffering from parotid pathology were subjected to cytology examination through fine needle aspiration. Thirty seven patients subjected to surgical operation have a histological comparison. We have proved the validity of the technique considering the sensibility, specificity and the accuracy. We didn't have FN we only had 1 FP that could be a suspect cytology. We had a 100% sensibility, a 75% specificity and 97.29% accuracy.

Adult↗
PubMed1993

[Echo-color Doppler in thyroid disease].

One-hundred and sixty-six patients affected with thyroid diseases were examined, together with 41 healthy volunteers, by means of color-Doppler US. Four main reference patterns were identified: no appreciable glandular flow (I); presence of signal in perinodular location (II); peri- and intranodular flow (III); increased vascularization (IV). In 72 cases, parenchymal and nodular goiters, with no signs of thyroid hyperfunction, were characterized as belonging to pattern III, while pattern II was observed in 57 nodular lesions; only in 7 patients was pattern III detected. Hyperfunctioning autonomous nodules exhibited pattern III in 10/11 cases and the same pattern was followed by the six carcinomas. Pattern IV resulted peculiar to Basedow disease and to glandular hyperplasia related to high values of circulating thyroid hormone (6 cases). When color-Doppler specificity in typifying the major thyreopathies can be confirmed, the possibility is actually in sight of reducing, in the near future, the number of thyroid scintigraphies and of US-guided needle biopsies.

Adolescent↗
PubMedDate not supplied

Vesicoureteral reflux in young patients: comparison of voiding color Doppler US with echo enhancement versus voiding cystourethrography for diagnosis or exclusion.

We assessed the accuracy of voiding color Doppler ultrasonography (US) with echo enhancement for diagnosis or exclusion of vesicoureteral reflux (VUR) versus voiding cystourethrography (VCUG) and evaluated patient tolerance of the echo-enhancing agent. One hundred twenty-two patients (ages range, 1 month to 17 years) with 244 ureterorenal units underwent voiding color Doppler US with echo enhancement, which was followed by VCUG on the same day. After US of the urinary tract, the bladder was filled with saline solution via catheter. Then an echo-enhancing agent was instilled, and color Doppler US was performed. Reflux was diagnosed when microbubbles appeared in the ureter or the pelvicaliceal system. VUR was detected in 98 units. All grades of reflux were identified. In 13 units (13.3%), grade I reflux diagnosed at voiding color Doppler US was not observed at VCUG. No reflux was detected in 146 units by either method. In 231 (94.2%) of the 244 ureterorenal units, there was concordance between the two methods. The echo-enhancing agent was well tolerated by all patients. Voiding color Doppler US with echo enhancement is useful for the diagnosis or exclusion of VUR, being as good as VCUG. Therefore, it may reduce the number of patients exposed to ionizing radiation.

Adolescent↗
PubMedDate not supplied

Perfusion MRI in normal and abnormal pituitary gland. A preliminary study.

Perfusion MRI (magnetic resonance imaging) of the pituitary gland was performed in 20 healthy volunteers and 63 patients with various lesions involving the pituitary gland. All patients underwent sequential contrast-enhanced MRI using spoiled gradient recalled sequences with high temporal resolution (7 seconds). Four pituitary areas (pituitary stalk, posterior lobe, postero-superior, and antero-inferior adenohypophysis) were tested with a selected region of interest. Maximal contrast percentual variation was calculated. The timing of enhancement in normal patients matched perfectly with normal pituitary vascularization. Abnormal timing in pathological condition was investigated.

Adenoma↗
PubMedDate not supplied

[The liver in patients with beta-thalassemia major. Determination of iron levels with magnetic resonance].

INTRODUCTION: We investigated the clinical usefulness of liver MRI in a large multicenter study because the control of iron concentration (LIC) is crucial in thalassemia major (TM) prognosis and conflicting results have been reported in small and heterogeneous groups of patients using Magnetic Resonance Imaging (MRI), the only very common non-invasive procedure. MATERIAL AND METHODS: One hundred and eight consecutive TM patients, selected according to a specific protocol, were included in the study. In 29 of these LIC was measured by atomic absorption spectrophotometry on liver biopsy and expressed as microgram/gr dry weight. MRI was performed with a 0.5 T superconducting unit. The ratio of the average signal intensity (SIR) of the liver to that of paraspinal muscle was calculated and expressed as a percentage. RESULTS: Mean +/- (SD) of SIR was 100 +/- 26% (test for normality: p = 0.02) and of LIC was 3677 +/- 4662 micrograms/g/dry liver (test for normality: p < 0.00001). The logit transformation of LIC (lLIC) achieved both normality of distribution of lLIC and linear regression of lLIC on SIR (t = 7.36; p < 0.00001) according to the equation: Y = -0.0136 + SIR* (0.157) = lLIC log10 (K-LIC/LIC) where K = 79.433. Thus the values of LIC are expressed by the equation LIC K/(1 + 10 y) micrograms/g/dry liver. Moreover, a mild correlation was found between SIR and AST (p = 0.01; r = -0.30), ALT (p = 0.02; r = -0.21), gamma GT (p = < 0.01; r = -0.37; r = -0.25). CONCLUSIONS: This study shows that LIC can be calculated as a function of SIR. A validation study is necessary before introducing this prediction rule in clinical practice.

Adult↗
PubMedDate not supplied

[Potential role of gravity in computerized tomography in neoplasms].

PURPOSE: The possible evolution of the usual CT signs in oncology makes the logical premise of our experience. Our goal was to transform instrumental findings in information richer in clinical yield, in compliance with the guidelines of the National Cancer Institute (Bethesda, Md, USA). MATERIAL AND METHODS: Our study was developed over a 3-year period and involved 432 selected patients with primary neoplasms. The lesions were in pulmonary, gastroenteric and genitourinary sites and stages differed (T2/T3, N0/N3, M0/M1); the Karnofsky score ranged 60-90. We integrated the tumor staging obtained with CT with gravitational tests by means of simple changes in the position of forced decubitus resulting in procubitus and triclinium-like positions (right and left lateral decubitus). We restudied only the cT class of each lesion, looking for a better depiction of the lesion-adjacent, fat, and compared the results the examinations in the standard versus the modified decubitus. Judgements were relative to the technical quality of the modified examination and to the potential impact of these findings on the following pTNM staging. RESULTS: In our 432 patients and only relative to the cT parameter, CT with standard decubitus correctly staged 312 lesions (mean accuracy: 72.2%) versus 352 for CT with modified decubitus (mean accuracy: 81.5%). Improvements were more marked in gastric (22.9% of 48 cases), vesical (23% of 26 cases) and colic (22.3% of 76 cases) lesions, and less marked in pulmonary (10.6% of 132 cases), ovarian (14% of 71 cases) and endometrial (17.1% of 70 cases) lesions. The routine application of pTNM verifications to CT staging helped show the most frequent causes of cTNM mistaging in solid lesions which, in most of the T2/T3 classes, involve the direct spread to an adjacent organ and the depth of invasion of adjacent structures. CONCLUSIONS: The combination and comparison of cTNM with pTNM are useful not only for final tumor staging but also to assess the pretreatment diagnostic accuracy of CT studies. Introducing gravitational tests and reading examinations in pairs improved lesion location, which is the most important technical information for subsequent prognosis and treatment and can help decrease pre-/post-treatment management costs.

Aged↗