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A Naoun

Publications and source records attributed to A Naoun.

At least 19 recordsLinked to original sources

[Evaluation of ultrasonography in the diagnosis of thyroid nodules].

Purpose of the paper: Specify the merits of ultrasonography in thyroid pathology. Outline ultrasonographic orienting criteria to identify the nature of thyroid nodules. Analysis of the paper: Thyroid ultrasonography allows detecting nodules that cannot be detected clinically or with radionuclide scanning. 20% of sonographic nodules cannot be palpated; 33% of sonographic nodules are not visible on radionuclide scans. Ultrasonography often shows multiple nodules where palpation and/or radionuclide scanning detect only one. When there are clinical signs of hyperthyroidism and uncertain biological findings, ultrasonography can relate a low-uptake nodule with an adenoma becoming autonomous, if the nodule appears to be hypodense. It allows monitoring the volume of nodules under freination therapy. Benign nodules may be liquid (15.7% of all cases); solid and isoechogenic (27.6%); solid and hyperechogenic (10.1%); solid and hypoechogenic (18.1%, including 88.5% toxic adenomas) or compound (26.4%). Comparison of the 2 series of nodules reveals the predominance of liquid and iso/hyperechogenic solid appearances for benign nodules (63.8%, excluding toxic adenomas). For cancers, the frequency of hypodense solid or compound nodules is 92.2%. Combining radionuclide scanning and ultrasonography allows further restricting the group of suspicious nodules, which have a low uptake and are hypodense or compound.

France↗

[Bone scintigraphy: diagnostic value and indications (author's transl)].

Bone scintigraphy is of considerable help in the diagnosis and follow-up of osteo-articular diseases. It also makes it possible to globally assess skeletal damage in cases with multiple bone lesions and to detect bone complications of diseases and therapies. To these advantages must now be added its contribution to the aetiological diagnosis of some arthropathies with subradiological lesions.

Bone Diseases↗

[Importance of bone scanning with Tc 99m in the supervision of hemodialysis patients with chronic renal failure (author's transl)].

Bone uptake of 99 m Tc diphosphonate may allow early diagnosis of renal osteodystrophy. Our study deals with 53 patients treated by repeated hemodialysis and reveals scanning abnormalities in 75% of them. Bone scanning provides information which are not visualized radiologically, especially scattered or located pulmonary calcifications (15% in our series). It is valuable in the follow-up of bone changes and is part of the necessary investigations before carrying out parathyroidectomy.

Adult↗

Radionuclide imaging in hip abnormalities.

The uptake of Tc-99m-diphosphonate was studied topographically and quantitatively on 258 diseased hips. For many diseased hips, bone scintigraphy provides items of information that complement the clinical, radiological, and biological data, with which it should always be compared. The localization, extent, and intensity of the uptake differ greatly according to the hip disorder studied, and depend not only on the cause of the lesion but also on its stage of evolution. Bone scintigraphy can shed light on the etiologic diagnosis of a painful hip at the beginning of its evolution, before definite roentgenographic signs appear, thanks to some very precise characteristics of the uptake, this is the case for transient osteoporosis of the hip, aseptic osteonecrosis, Legg-Perthes disease, early arthritis of the hip joint, and stress fractures of the femoral neck or of the pubic rami.

Adult↗

[Scintigraphic characteristics of coxopathies: etiologic importance].

Morphological and quantitative studies of the uptake of diphosphonates labelled with technetium 99m were done on 179 pathological hips : 106 aseptic osteonecroses of the femoral head, including 20 at an early stage, 11 algodystrophias (transitory osteoporoses of the hip), 20 coxarthrosis, 16 cases of Paget's disease, 12 isolated malignant lesions of the femoral neck. The location, extent and intensity of the uptake are very variable and depend not only on the etiology of the lesions but also on their stage of evolution. Bone scintigraphy provides, for numerous pathological hips, pieces of information which complete the results of the clinical, radiological and biological study, with which it should always be compared. It can shed light on the etiologic diagnosis of a painful hip at the beginning of its evolution, before the appearance of rare x-ray signs, thanks to certain very precise characteristics of the labelling. This is the case for algdystrophias, osteonecroses, coxitis and strain fractures of the femoral neck.

Femur Head Necrosis↗

[Interpretation of and indications for bone scintiscans].

The interpretatiton of a bone radioisotope scan requires perfect knowledge of normal skeletal appearances, shadows outside the bones and the various methods of expression of bony lesions: generally hyperfixations but sometimes isofixations or even hypofixations. A bone scan permits one to make an overall assessment of multiple bony lesions, determine the extent of a lesion, detect bony complications of a disease or treatment and seek the bony origin of a pain.

Bone Diseases↗

[Ochronotic hip disease. Radiological and scintigraphic study (author's transl)].

A radiological and scintigraphic study of hte femoral head removed from a patient at the time of insertion of a total prosthesis of the hip in a patient with ochronotic rheumatic disease. The images obtained differ from those seen in aseptic osteonecrosis and confirm the hypotheses of Lagier, who has described several forms of arthrotic remodelling in ochronotic hip disease.

Female↗

[Diagnostic value of localized hypofixations in the radioisotope scanning of bones].

The scintigraphic appearances of all localized, evolutive bone lesions, whatever their nature, is usually a "hot spot", that is a zone of hyperfixation of the radioactive material. False negatively scintigraphs are, however, noted: the scintigraphic image appears normal, without a zone of hyperfixation, although radiographs of the skeleton are pathological. The 8 cases presented in this article demonstrate that certain bone lesions (aseptic osteonecrosis and malignant destruction of bone) may sometimes be represented as real zones of hypofixation, as veritable "cold spots". These areas of hypofixation result from either a local interruption in the vascularization, which prevents the isotope from reaching the bony structures, or from a quantitative insufficiency of the bony tissue, this being replaced by neoplastic tissue which, in the cases studied, fixed labelled Bleomycin or iodine-131. These areas of hypofixation and any absences of fixation really are the scintigraphic images of areas of osteolysis or of aseptic osteonecrosis but they are generally masked by hyperfixation around the lesion that results in reactional osteogenesis and hypervascularization.

Aged↗

The diagnostic value of 99m Tc-diphosphonate bone imaging in transient osteoporosis of the hip.

We present topographic and quantitative studies of 99m Tc-diphosphonate bone scans from 46 patients and 25 control subjects in which we found transient osteoporosis of the hip (TOH) (12 cases--2 bilateral), early aseptic osteonecrosis of the femoral head (19 cases--2 bilateral), early coxitis (11 cases), and stress fracture of the femoral neck (4 cases). Active TOH was characterized by intense, homogeneous increased uptake of the entire femoral head, extending to the acetabulum and the neck, and sometimes to the shaft. The scintigram of TOH differed greatly from that in the other hip disorders studied. Bone scintigraphy can help to diagnose the cause of pain in a hip before definite roentgenographic signs appear.

Adult↗