The ability of 67Ga scintigraphy to detect the lesions of Echinococcus multilocularis infection: preliminary results.

AIM: To assess the ability of 67Ga scintigraphy to detect the lesions of Echinococcus multilocularis (EM) infection. MATERIALS AND METHODS: An animal model of EM infection was developed. The infected tissues taken from stock infection were placed into the abdominal cavity of uninfected animals operatively. The success of implantation was controlled 20-25 days after implantation. Five infected and 2 healthy animals were studied. All of the animals were examined by ultrasound before the scintigraphic evaluation. After the injection of 7.4 MBq (200 microCi) 67Ga citrate intravenously, static images from the whole anterior thorax and abdomen were obtained at 24, 48 and 72 hours. Visual and semiquantitative analyses were performed. In semiquantitative analysis, an irregular region of interest was drawn over the thorax as the background, excluding the heart and a second region of interest was drawn over the abdomen, excluding the liver and spleen. Abdomen/ background ratios were calculated using the mean counts. RESULTS: In the visual evaluation, it was noticed that there was considerably increased 67Ga uptake in the abdomens of the infected animals. In infected animals, mean abdomen/background ratios at 48 and 72 hours (3.76 +/- 1.04, 4.13 +/- 0.72, respectively) were increased compared with mean abdomen/background ratios at 24 hours (2.94 +/- 0.77). These increases in abdomen/background ratios were statistically significant at 72 hours (p = 0.04). Between the infected animals and control group, mean abdomen/background ratios were compared, and statistically significant differences were found in the images obtained at 48 and 72 hours. CONCLUSION: Imaging at 72 hours seems to be more suitable imaging time for the diagnosis of alveolar echinococcosis. 67Ga scintigraphy may successfully demonstrate the lesions of EM infection localized intraperitoneally. The method of 67Ga scintigraphy is useful because it is simple, non-invasive and relatively safe.

Effects of normovolaemic haemodilution on middle cerebral artery blood flow velocity and oxygen delivery.

BACKGROUND AND OBJECTIVE: Assessment of the effects of normovolaemic haemodilution on middle cerebral artery blood flow velocity with transcranial Doppler ultrasonography, intracranial pressure, cerebral perfusion pressure, arterial oxygen content and cerebral oxygen delivery. METHODS: Normovolaemic haemodilution was induced in rabbits under general anaesthesia, and the haematocrit was allowed to decrease to 30% in Group 1 (n = 6) and to 20% in Group 2 (n = 6). Peak systolic and diastolic velocities, mean blood flow velocity, and pulsatility and resistance indices of the middle cerebral artery were measured by transcranial Doppler ultrasonography. Changes in intracranial pressure, cerebral perfusion pressure, arterial oxygen content and cerebral oxygen delivery were also assessed. RESULTS: In Group 2, middle cerebral artery blood flow velocity increased from 0.4 +/- 0.01 to 0.51 +/- 0.02 m s(-1) after the induction of normovolaemic haemodilution (P = 0.04), while arterial oxygen content decreased from 16.2 +/- 0.1 to 8.5 +/- 0.1 mLdL(-1) (P = 0.002). The decrease in cerebral oxygen delivery from 6.5 +/- 0.2 to 4.3 +/- 0.2 was also significant (P = 0.02). However, no associated changes in intracranial pressure and cerebral perfusion pressure could be demonstrated. CONCLUSIONS: Normovolaemic haemodilution resulted in an increase in the mean blood flow velocity of the middle cerebral artery. However, this increase did not compensate for the consequences of the altered oxygen delivery to the brain when the haematocrit was reduced to 20%.

Renal histomorphometry and resistance index in children with renal disease.

PURPOSE: The aim of this study was to examine the relationships between the renal resistance index (RI) and histomorphometric variables measured in children with glomerular or nonglomerular renal disease. Patients and Methods The medical records, sonography reports, and biopsy specimens of 30 children with glomerular or nonglomerular renal disease (mean age, 11.0 +/- 4.7 years; range, 2. 5-17 years) who underwent sonographic evaluation and biopsy of the right kidney were retrospectively studied. Biopsy specimens were evaluated for glomerular surface density, number of glomeruli in the stroma, capillary surface density, number of capillaries within the glomeruli, and the diameters of the afferent arterioles. RESULTS: The RI was negatively correlated with age in patients 2.5-4.0 years old (rho = -1.0, p < 0.001). The RI was positively correlated with serum creatinine levels (rho = 0.63, p < 0.001), and the RI differed significantly between patients with abnormally high and age-appropriate serum creatinine levels (0.8 +/- 0.1 and 0.6 +/- 0.1, respectively; p = 0.002). No differences in age, histomorphometric variables, RI, or arteriolar diameter were found between patients who had interstitial fibrosis and those who did not, and the RI was not correlated with histomorphometric variables in either group. However, the mean RI was significantly higher in patients with severe fibrosis than in those with mild fibrosis. In those with severe fibrosis, the RI was negatively correlated with number of glomeruli in the stroma (rho = -0.975, p < 0.01), glomerular surface density (rho = -0.931, p < 0.05), number of capillaries within the glomeruli (rho = -0.989, p < 0.01), and arteriolar diameter (rho = -1.00, p < 0.01). CONCLUSIONS: The RI was correlated with histomorphometric variables in patients with severe interstitial fibrosis and could be useful in the follow-up of these patients.

Diagnostic value of MR arthrography in detection of intrinsic carpal ligament lesions: use of cine-MR arthrography as a new approach.

Twenty-five patients with chronic wrist pain and a preliminary diagnosis of carpal instability were examined with conventional MR imaging and MR arthrography with single compartment intra-articular injection. A new cine-MR arthrography technique, with image acquisition at every 5 s during intra-articular injection, was performed in 17 subjects. The purpose of this study was to determine the diagnostic value of MR arthrography in ligamentous lesions of the wrist and to assess the value of cine-MR arthrography in comparison with arthroscopy and/or surgery. Magnetic resonance arthrography, a semi-invasive technique, increased the diagnostic accuracy of intrinsic carpal ligament injuries. Cine-MR arthrography can be considered as a promising technique especially for the evaluation of lunatotriquetral and scapholunate ligament injuries of the wrist.

Value of intraplacental villous artery Doppler measurements in severe preeclampsia.

Blood flow velocity waveforms were recorded by color Doppler ultrasound from intraplacental villous and umbilical arteries in 20 normal and 23 severe preeclamptic pregnancies. The results of the resistance index measurements in intraplacental villous arteries were 0.51 +/- 0.037 and 0.55 +/- 0.052 in healthy controls and preeclamptics respectively, which was not significantly different. Resistance indices showed a decrease through the umbilical cord from fetus to placenta in both groups. We also noted that Doppler examination of the umbilical cord might be an early indicator of fetal compromise. Detectable intraplacental villous flows were in normal limits even in patients with abnormally high umbilical resistance indices and failure to detect villous artery color Doppler flow signals is probably associated with fetal compromise. We conclude that Doppler measurements from the intraplacental arteries cannot be used in clinical management of patients with severe preeclampsia.