Myxoid intraneural cysts of external popliteal ischiadic nerve. Report of 2 cases studied with ultrasound, computed tomography and magnetic resonance imaging.

Peripheral neuropathy of the external popliteal ischiadic nerve caused by intraneural cysts is a very rare and peculiar pathological phenomenon compared with diseases associated with extraneural cysts or colliquative phenomena of solid nervous lesions. Two cases of peripheral neuropathy of the external popliteal ischiadic nerve caused by intraneural cysts and evaluated with ultrasound, computed tomography and magnetic resonance are described. The diagnostic efficacy of these imaging modalities is also evaluated with particular reference to MR capability to define the morphology of such lesions and their relationships to the surrounding structures. It is not yet possible to obtain a correct diagnosis about histopathologic features by means of the imaging techniques currently available. Nevertheless, they do provide information about the involvement of the neighboring areas, which are useful indications for possible surgical treatment of the disease.

[The usefulness of echographic monitoring during the removal of at risk IUDs]. / Utilita del monitoraggio ecografico nella rimozione degli IUD a rischio.

PIP: Among the undesirable events which can take place during IUD use is the occasional disappearance of the "retrieval" string. When this happens, however, with the advent of echographic monitoring, a simple procedure can be used to determine the position and the condition of the IUD. When the time comes to remove the IUD for any reason, a technical problem is posed. Up to now, in most cases, cautious instrumental maneuvers in searching for the string in the cervical canal were required. However, this difficult procedure can be simplified with the help of echographic monitoring, according to an Italian study. The technique consists of several phases. In the 1st phase, the echographic exam allows for evaluation of the morphology and dimensions of the uterus, and also for establishment of whether the disappearance of the string is just due to bad positioning or whether the string has actually disappeared. Then, in the 2nd phase, the cavity is penetrated with a Novak cannula and, under echographic guidance, it is hooked onto 1 of the branches of the device and pulling action is applied. This is the greatest advantage of using echographic monitoring because often it is not even necessary to push the Novak excessively toward the base of the uterus, since in most cases the hookup becomes evident and then the success of the maneuver is confirmed by visualization of the IUD's movement toward the external uterine orifice. If the patient then chooses to continue use of the contraceptive, a new IUD can be inserted under the control of echographic monitoring. The overall finding of this study was that IUD removal was not difficult and was fairly well tolerated in all of the cases. This did not depend upon parity, the type of device, or proper or improper positioning. No hemorrhage, inflammation, or other type of complication was found. For these reasons, echographic monitoring should be used not only to diagnose improper IUD positioning or other related complications, but also to help in those cases where the retrieval string has disappeared.^ieng

[Magnetic resonance in the diagnosis of thyroid diseases]. / La Risonanza Magnetica nella diagnostica delle malattie della tiroide.

Previous clinical experience in the study of the soft tissues of the neck region has pointed out the accuracy of MRI in terms of high definition and contrast resolution. Seventy-seven patients with thyroid diseases were examined to define the possible role of MRI in the diagnosis of these conditions. In the patients affected with thyroiditis, MR findings were not specific, showing increased glandular volume and signal inhomogeneity. MR examinations of struma allowed an accurate evaluation of glandular size; furthermore, more information was obtained than with other imaging modalities in the cases with mediastinal involvement. On T2-weighted images, adenomas were always hyperintense, whereas variable signal intensity was seen on T1-weighted scans, with the exception of Hürthle cell adenomas, which were hyperintense on both T1- and T2-weighted sequences. MRI proved to be reliable in the depiction of tumor spread at both glandular and extraglandular levels. The distinction between scar fibrosis and relapse was also possible, in the cases undergoing postoperative follow-up. In conclusion, MRI emerges as a diagnostic tool complementary to other imaging techniques. However, in selected conditions--e.g., mediastinal struma and tumors--and in the postoperative follow-up, MRI can be considered the method of choice.

[Magnetic resonance in the study of inflammatory diseases of the pancreas]. / La Risonanza Magnetica nello studio delle malattie infiammatorie del pancreas.

The role of diagnostic imaging modalities in pancreatic inflammatory diseases is to assess gland damage and peripancreatic tissue involvement. The artifacts related to breathing and to peristaltic movements can be partially resolved with the optimization of acquisition parameters, which allows MRI to be suggested for the assessment of pancreatic inflammatory conditions. Sixty-nine patients with pancreatic inflammatory diseases (20 acute and 49 chronic pancreatitis cases) were examined. MRI was performed with a 0.5-T superconductive magnet and T1- and T2-weighted spin-echo (SE) sequences. In 4 of 20 acute pancreatitis patients image quality was poor. MRI in acute pancreatitis demonstrated glandular edema, intraparenchymal necrosis and the extent of peripancreatic fluid collections; in chronic pancreatitis MRI depicted glandular atrophy and Wirsung duct dilatation and detected the presence of pseudocysts. Even though its spatial resolution is lower than that of CT, MRI can provide useful pieces of information in inflammatory diseases of the pancreas, much more so after the introduction of Fast SE sequences and of fat-saturation techniques which are likely to make MR examinations of the pancreas more widely used.

[Magnetic resonance imaging of the esophagus with lumen opacification using a specific contrast agent]. / Studio dell'esofago con risonanza magnetica con opacizzazione del lume mediante impiego di un mezzo di contrasto specifico.

A new contrast agent has been developed for the opacification of the esophageal lumen in Magnetic Resonance (MR) Imaging. The contrast agent consists of an emulsion of low-density and high-viscosity barium paste employed for the CT study of the esophagus (E.Z.E.M., Westbury, USA) and a small amount of Gadolinium-DTPA (Magnevist, Schering, Germany), diluted in 3 ml of saline solution. In vitro evaluation of the contrast solution showed high-signal intensity on T1-weighted SE sequences. The study was subsequently performed on 5 healthy volunteers and 30 subjects with clinical indication for MR Imaging of the chest. The complete opacification of the esophagus was obtained in 12 of the 16 patients (75%) who presented no pathological involvement of the esophagus. The esophageal lumen was completely opacified in 8 patients with esophageal carcinoma and in 1 case of esophageal leiomyoma. In the cases with esophageal carcinoma, lumen opacification allowed the evaluation of tumor growth (concentric or eccentric), a more detailed definition of tumor extent, with assessment of neoplastic wall thickening, and the evaluation of the possible infiltration of adjacent organs. Lumen opacification was obtained in 8 of 10 patients (80%) affected with other chest conditions secondarily involving the esophagus. In these cases, lumen opacification helped to localize the esophagus and to evaluate its involvement by adjacent tumors.

[Pathologic conditions in pregnancy. Preliminary evaluation of the effectiveness of magnetic resonance]. / Condizioni patologiche nella gravidanza. Valutazioni preliminari sull'efficacia della Risonanza Magnetica.

Some authors suggested that MR imaging could represent an effective diagnostic alternative in the study of pathologic conditions of mother and fetus during pregnancy. To verify the actual role of MR imaging, we examined 20 patients in the 2nd and 3rd trimester of gestation, after a preliminary US examination. Fifteen patients presented fetal or placental pathologies; in 4 patients the onset of the pathologic condition occurred during pregnancy; in 1 case of US diagnosis of fetal ascites, MR findings were normal and the newborn was healthy. As for placental pathologies, our series included a case of placental cyst, two hematomas between placenta and uterine wall, and two cases of partial placenta previa. As for fetal malformations, we evaluated a case of omphalocele, one of Prune-Belly syndrome, a case of femoral asymmetry, one of thanatophoric dwarfism, a case of thoracopagus twins with cardiovascular abnormalities, two fetal hydrocephali, and three cases of pyelo-ureteral stenosis. As for maternal pathologies during pregnancy, we observed a case of subserous uterine fibromyoma, one of right hydronephrosis, one of protrusion of lumbar intervertebral disk, and a large ovarian cyst. In our experience, MR imaging exhibited high sensitivity and a large field of view, which were both useful in the investigation of the different conditions occurring during pregnancy. In the evaluation of fetal and placental abnormalities, especially during the 3rd trimester, the diagnostic yield of MR imaging suggested it as a complementary technique to US for the evaluation of fetal malformations and of intrauterine growth retardation.