105Pd NMR and NQR study of the cubic heavy fermion system Ce3Pd20Si6.

We report 105Pd nuclear magnetic resonance (NMR) and nuclear quadrupolar resonance (NQR) measurements on a single crystal of Ce3Pd20Si6, where antiferroquadrupolar and antiferromagnetic orders develop at low temperature. From the analysis of NQR and NMR spectra, we have determined the electric field gradient (EFG) tensors and the anisotropic Knight shift (K) components for both inequivalent Pd sites-Pd(32f) and Pd(48h). The observed EFG values are in excellent agreement with our state-of-the-art density functional theory calculations. The principal values of the quadrupolar coupling are [Formula: see text] MHz and [Formula: see text] MHz, for the Pd(32f) and Pd(48h) sites, respectively, which is large compared to the Larmor frequency defined by the gyromagnetic constant [Formula: see text] MHz/T for 105Pd. Therefore, the complete knowledge of K and the EFG tensors is crucial to establish the correspondence between NMR spectra and crystallographic sites, which is needed for a complete analysis of the magnetic structure, static spin susceptibility, and the spin-lattice relaxation rate data and a better understanding of the groundstate of Ce3Pd20Si6.

[Perioperative complications in carotid endarterectomy with respect to the stage of the cerebrovascular disease]. / Perioperacijske komplikacije karotidnih endarterektomija s obzirom na stadij cerebrovaskularne bolesti.

Records of perioperative complications following 407 consecutive carotid endarterectomies performed in 366 patients in the 18-year period have been presented. The complications are categorized according to the clinical stage of vascular disease, that is, according to the indications for the surgery. Out of the total number, 46 (11.3%) operations were done in the 1st, asymptomatic stage of disease, for the haemodinamically significant stenoses and ulcerated plaques; 173 (42.5%) in the 2nd clinical stage for hemispheral and nonhemispheral transient ishemic attacks (TIA) and reversible neurologic deficits (RIND); 3 (0.7%) in the 3rd stage which is a progressive cerebrovascular stroke and 185 (45.5%) in the 4th clinical stage of the disease, in patients with previous cerebral infarction and a permanent neurologic deficit. The rate of a temporary and permanent neurologic deficit, as well as mortality in the first stage of the disease equals zero. In the second stage of the disease, the rate of a temporary neurologic postoperative morbidity increases to 1.7%, of a permanent neurologic morbidity to 1.2%, while the rate of mortality is 1.2%. In the 3rd and 4th stage, those rates amount to 66.7%, 0% and 33.3%, and 1.1%, 3.8% and 1.6%, respectively. The rates of perioperative morbidity and mortality are in proportion to the scope of preoperative brain dysfunction. Results of this work suggest the necessity of categorization of patients, candidates for carotid endarterectomy, according to the clinical stage of the disease, which will enable a better comparison with other authors' results, give a more reliable view on the efficacy of the surgical treatment and justify the surgeons' attitude towards indications.(ABSTRACT TRUNCATED AT 250 WORDS)

Iohexol versus meglumine-Ca-metrizoate in cerebral angiography. A randomized double-blind cross-over study.

The tolerance and suitability of iohexol in cerebral angiography was compared in a clinical trial with meglumine-Ca-metrizoate in 20 patients. A preference for iohexol after injection into the external carotid artery in a paired comparison was established in 84.2 per cent of the patients. The difference was also statistically significant (p less than 0.01) with regard to the intensity of discomfort estimated according to a four grade scale. The milder sensations occurred more frequently with iohexol (1.21), while moderate as well as severe reactions were caused by metrizoate (2.78). These reactions caused discomfort and occasionally movements, with blurring of the films. Both contrast media provided sufficient information to enable an accurate radiologic diagnosis.

Large and giant intracranial aneurysms. A radiologico-clinical study.

The brain scans and cerebral angiograms of 13 patients with intracranial aneurysms larger than 15 mm. in diameter are analysed. The radiological findings obtained are compared with clinical symptoms and signs. Twelve patients had genuine aneurysms and one patient a posttraumatic false aneurysm. Post-contrast CT in transversal and coronal plane revealed the real size of the aneurysm in 7 cases of intraluminal thrombosis. Cerebral angiography demonstrated the presence of aneurysms, their anatomic relations and haemodynamic changes.