Diffusion-weighted magnetic resonance imaging is more sensitive than dimercaptosuccinic acid scintigraphy in detecting parenchymal lesions in children with acute pyelonephritis: A prospective study.

INTRODUCTION: Static renal scintigraphy is the gold standard for detection of inflammatory changes in the renal parenchyma in acute pyelonephritis. Our aim was to determine whether diffusion-weighted magnetic resonance imaging (DW-MRI) was comparable with static renal scintigraphy (DMSA-SRS) to demonstrate acute renal parenchymal lesions. OBJECTIVE: To compare 99mTc-dimercaptosuccinic acid static renal scintigraphy (DMSA-SRS) with diffusion-weighted magnetic resonance imaging (DW-MRI) for detecting acute inflammatory changes in the renal parenchyma in children with febrile urinary tract infection. METHODS: Thirty-one children (30 girls) aged 3-18 years with a first episode of febrile UTI without a previously detected congenital malformation of the urinary tract, were prospectively included. DMSA-SRS and DW-MRI were performed within 5 days of diagnosis to detect renal inflammatory lesions. The DW-MRI examination was performed without contrast agent and without general anesthesia. Late examinations were performed after 6 months using both methods to detect late lesions. RESULTS: DW-MRI confirmed acute inflammatory changes of the renal parenchyma in all 31 patients (100%), mostly unilateral. DMSA-SRS detected inflammatory lesions in 22 children (71%; p = 0.002). The lesions were multiple in 26/31 children (84%) on DW-MRI and in 9/22 (40%) on DMSA-SRS. At the control examination, scarring of the renal parenchyma was found equally by DW-MRI and DMSA-SRS in five patients (16%), three of whom were the same patients. The overall concordance of positive and negative late findings occurred in 87% of patients. There was correspondence in the anatomical location of acute and late lesions. DISCUSSION: The clinical significance of acute and late parenchymal findings on DWI-MR is yet to be determined. A limitation of our study is the age of the patients (older than 3 years) who are less sensitive to scar development; therefore, a smaller number of patients with scars could be analyzed during control examination. Further studies using the DW-MRI should confirm its reliability to detect acute and late lesions in younger children and infants and determine the clinical consequences. CONCLUSION: DW-MRI has higher sensitivity for detecting acute renal inflammatory lesions and multifocal lesions than DMSA-SRS. The incidence of scars was low and corresponded with the anatomical location of acute and late lesions.

Radionuclide cholescintigraphy in genetically confirmed Rotor syndrome.

A 7-year-old girl had been followed up for persistent conjugated hyperbilirubinemia since birth. Alanine aminotransferase, aspartate aminotransferase and γ-glutamyl transpeptidase activity was within the normal range, and liver protein synthesis had always been normal. Infectious etiology of jaundice, autoimmune diseases, drug-induced liver injury, hemolytic anemia, α-1 anti-trypsin deficiency, Wilson disease and Gilbert syndrome were ruled out. At the age of 8 years the patient underwent radionuclide dynamic cholescintigraphy, indicating poor accumulation of the radiotracer in the liver on one hand, and severe retention of the radiopharmaceutical in the blood pool (including the heart) on the other hand. Rotor syndrome was suspected and finally confirmed on molecular analysis. This case represents the first cholescintigraphy report in a pediatric patient with genetically proven Rotor syndrome.

Myocardial perfusion imaging parameters: IQ-SPECT and conventional SPET system comparison.

Technological advancement in hardware and software development in myocardial perfusion imaging (MPI) leads to the shortening of acquisition time and reduction of the radiation burden to patients. We compared semiquantitative perfusion results and functional parameters of the left ventricle between new dedicated cardiac system with astigmatic collimators called IQ-SPECT (Siemens Medical Solutions, USA) and conventional single photon emission tomography (SPET) system equipped with standard low energy high resolution collimators. A group of randomly selected 81 patients underwent consecutively the MPI procedure on IQ-SPECT and on conventional SPET systen, both without attenuation correction. The summed scores and the values of the functional parameters of the left ventricle: ejection fraction (EF), end-systolic and end-diastolic volumes (ESV, EDV) received from the automatic analysis software were compared and statistically analyzed. Our results showed that summed scores values were significantly higher for the IQ-SPECT system in comparison to the conventional one. Calculated EF were significantly lower for IQ-SPECT, whereas evaluated left ventricular volumes (LVV) were significantly higher for this system. In conclusion, we recorded significant differences in automatically calculated semiquantitative perfusion and functional parameters when compared uncorrected studies obtained by the IQ-SPECT with the conventional SPET system.

Safety and efficacy of surgical treatment of carotid stump syndrome: pilot study.

Surgical exclusion of the internal carotid artery (ICA) stump combined with endarterectomy of the external carotid artery is an established treatment approach. The aim of this pilot study was to compare the risk of cerebrovascular events between surgical treatment and best medical treatment in patients with ICA occlusion and carotid stump syndrome. Forty patients (23 males; age: 43-80 years; mean age: 61.1 ± 9.0 years) with carotid occlusion and carotid stump syndrome were enrolled. Ten patients with asymptomatic ICA occlusion and 10 patients with symptomatic ICA occlusion and carotid stump syndrome were enrolled to the best medical therapy group. Patients with chronic ICA occlusion, carotid stump syndrome, and one (15 patients) or recurrent (three patients) episodes of ipsilateral stroke or transient ischemic attack were enrolled to the surgical group. Neurological examination was undertaken on the day of randomization and then every 6 months in all patients for 4 years. All vascular events and death were recorded. Only one vascular event occurred in patients with symptomatic ICA occlusion without recurrent stroke or transient ischemic attack who were treated medically. No other vascular event was noted in the other subgroups. One patient with symptomatic carotid occlusion without recurrent stroke died due to myocardial infarction 6 months after surgery. Surgical treatment of carotid stump syndrome seems to be a safe procedure. Nevertheless, the benefit of a surgical approach in comparison with the best medical treatment is not clear.

I-131 false positive uptake in a huge parapelvic renal cyst.

A male patient had undergone total thyroidectomy for thyroid papillary carcinoma. He was administered thyroablation activity of radioiodine. Whole body imaging after diagnostic activity of 131-I demonstrated intense radioiodine uptake in the right side of the upper abdominal region. The serum thyroglobulin level was low. Ultrasonography demonstrated a large irregular anechoic structure in the centre of the right kidney--a cyst in the parapelvic region. Renal cysts can lead to erroneous interpretation of radioiodine scintigraphy.

Moyamoya disease is associated with endothelial activity detected by anti-nestin antibody.

AIM: To describe the case history and new histopathological findings of a young woman suffering from moyamoya disease. METHODS: The patient underwent brain computed tomography, magnetic resonance imaging and brain angiography. Vessel samples of a. temporalis superficialis were processed by standard histopathological and immunohistochemical methods by analysis of VEGF, VEGFR and nestin expression. RESULTS: Brain angiography revealed both internal carotid artery stenoses and stenoses of the anterior cerebral arteries. Stenotic parts of vessels were accompanied by coiled and elongated vessels with a picture of "smoke puffs carried away by breeze" after contrast medium application. Histological examination showed: obstruction of lumen, fibrocellular intimal thickening, tortuosity and disruption of internal elastic lamina. Imunohistochemistry confirmed a defect of the internal elastic membrane of the muscular arteria and progressive intimal thickening accompanied by abnormal smooth muscle cells and, VEGF/VEGFR expression in intima. Nestin positivity in endothelium of arteria indicated that endothelial cells are activated. CONCLUSION: We found that the endothelium of affected vessels is nestin positive. This, together with the finding of VEGF/VEGFR expression, might suggest an active angiogenetic process We present a new conception of pathogenesis but further studies with higher number of patients are necessary to elucidate the role of these growth factors in the moyamoya disease.

Brain single photon emission tomography and hypercapnia test in testing cerebrovascular reserve capacity, in Moya moya disease.

Moya moya is a progressive cerebral occlusive vasculopathy, rare in European countries. We describe a case of a young woman with right-hand side hemiparesis, mixed expressive aphasia, organic psychosyndrome and cognitive malfunction. Detailed imaging methods displayed bilateral stenosis of the internal carotid artery, bilateral ischemic cerebral changes and bilateral perfusion deficit, which guided us to the final diagnosis. Before the bypass surgery, cerebrovascular reserve capacity (vasoreactivity), by the brain single photon emission tomography and hypercapnia, were assessed and the lower cerebrovascular reserve was demonstrated. Bilateral bypass surgery with extracranial-intracranial anastomosis, improved the neurological deficit. Diagnosis was confirmed by histological examination of the vessel wall specimen.