Internal carotid artery stenosis: comparison of duplex scan and magnetic resonance angiography with digital subtraction angiography.

OBJECTIVE: We compare duplex scan (DS) and magnetic resonance angiography (MRA) with digital angiography (DGA) in respect to accuracy in measuring internal carotid artery (IC) stenosis in symptomatic patients. METHOD: Ten symptomatic patients with IC stenosis greater than 70% previously diagnosed by DS were submitted to another DS and to both MRA and DGA. Both ICs from each patient (total 20 ICs) were evaluated by physicians blinded for the results of other tests. DS and MRA were compared with DGA, using the intraclass correlation coefficient (r) and its 95% confidence interval (95% ci). For each diagnostic test, the study group (20 Ics) was also divided in surgical patients (IC stenosis between 70 and 99%) and non surgical patients, using kappa concordance coefficient (k) to compare the results. RESULTS: Main comparisons are: DS and DGA, r = 0.71 (0.4 - 0.87); MRA and DGA, r = 0.61 (0.25 - 0.82). After division into surgical vs. non-surgical groups, k = 0.857 (p < 0.0001) between DS and DGA; and k = 0.545 (p = 0.003) between MRA and DGA. Most DS and MRA errors occurred in IC sub-occlusions. CONCLUSION: The results suggest that when they are used together, DS and non-contrast MRA may substitute DGA in the evaluation of patients for IC stenosis surgery, except when there is discordance between their results or when the methods show sub-occlusive stenosis.

Comparison between the NASCET method and subjective visual impression in the evaluation of internal carotid artery stenosis.

OBJECTIVE: To evaluate the accuracy of subjective visual impression (SVI) of an experienced neuro-radiologist in the measurement of the degree of internal carotid artery (IC) stenosis evaluated by digital angiography (DGA). METHOD: Ten symptomatic patients with internal carotid stenosis greater than 70% in a previous duplex scan were submitted to DGA. The degree of stenosis in both sides (symptomatic and asymptomatic) were evaluated by the same neuro-radiologist who gave his SVI and applied the NASCET method immediately after. Both methods were compared using the intraclass correlation coefficient (r) and its 95% confidence interval (95% ci). For each method, the sample (20 ICs) was also divided in surgical (stenosis between 70 and 99%) and non surgical ICs, using kappa concordance coefficient (k) to compare the results. RESULTS: The results comparing the 20 values obtained by each method are: r = 0.90 (95% ci: 0.77-0.96). Dividing the sample in surgical and non surgical ICs, k = 0.857, p < 0.0001; sensitivity = 100% (39.6%-100%); specificity = 93.8% (67.7%-99.7%); positive predictive value = 80% (29.9%-98.9%); negative predictive value = 100% (74,7%-100%). CONCLUSION: The SVI may be used by at least some experienced neuroradiologists as a preliminary tool to evaluate the degree of IC stenosis with DGA, but a standardised and well established method should be routinely performed.

Inhibitory activity of Paenibacillus polymyxa SCE2 against human pathogenic micro-organisms.

Paenibacillus polymyxa strain SCE2 was shown to inhibit the growth of different potential human pathogenic bacterial strains and fungi in vitro. To determine the genetic characterization of this antimicrobial substance, strain SCE2 was transformed with plasmid pTV32(Ts), a delivery vector for Tn917-lac. After transposition, four mutants were shown to have lost their capability to inhibit Micrococcus sp. and Staphylococcus aureus RN450, but they continued to inhibit the growth of Corynebacterium fimi NCTC7547 and Escherichia coli HB101. Hybridization experiments using the DNA of the four mutants digested with different endonucleases and pTV32(Ts) as a probe showed that the place of insertion of Tn917-lac in the chromosome was the same in mutants 4 and 36 and in mutants 31 and 59, but different between these pairs. It is thought possible that more than one antimicrobial substance is being produced by strain SCE2.

Embolizacao esplenica parcial. / Partial splenic embolization

Neste trabalho apresentamos os resultados da embolizacao esplenica parcial (EEP) em pacientes portadores de hipertensao porta, esplenomegalia e hiperesplenismo . Foram acompanhados 12 pacientes, no periodo comprendido entre marco de 1979 e junho de 1983. Todos eram portadores de esquistossomose mansonica, em sua forma hepatoesplenica. Dois pacientes apresentavam cirrose hepatica associada. O metodo mostrouse seguro e destituido de complicacoes, tendo sido observada reducao gradual do volume do baco e correcao do hiperesplenismo, em todos os casos