Prognostic value of the acute DMSA scan in children with first urinary tract infection.

We attempted to verify in a group of 101 children with first urinary tract infection whether it was possible to identify groups of patients with different risks of developing renal scarring by taking into account both the extent of kidney involvement documented in the acute phase of infection using a dimercaptosuccinic acid (DMSA) scan, and the presence or absence of vesicoureteral reflux (VUR). The frequency of persistent lesions in kidneys with mild-moderate lesions (less than 50% of kidney involvement) in the presence of VUR or in non-refluxing kidneys was similar (P=0.1447), while the frequency of persistent lesions in kidneys with severe lesions in the presence of VUR was significantly higher than the frequency of persistent lesions in non-refluxing kidneys (P=0.0089). The extent of kidney involvement and the presence of VUR make possible the identification of different categories of risk of scarring: in the "low risk group" (normal kidney with/without VUR) the risk of scarring is 0%; in the "intermediate risk group" (mild lesions with/without VUR; extensive lesions without VUR) the risk of scarring is between 14% and 38%, while in the "high risk group" (extensive lesions with VUR) the risk of scarring is 88%. Quantifying the risk of scarring could help in planning the treatment or in modifying the later strategy.

Regional expiratory flow limitation studied with Technegas in asthma.

Regional expiratory flow limitation (EFL) may occur during tidal breathing without being detected by measurements of flow at the mouth. We tested this hypothesis by using Technegas to reveal sites of EFL. A first study (study 1) was undertaken to determine whether deposition of Technegas during tidal breathing reveals the occurrence of regional EFL in induced bronchoconstriction. Time-activity curves of Technegas inhaled during 12 tidal breaths were measured in four asthmatic subjects at control conditions and after exposure to inhaled methacholine at a dose sufficient to abolish expiratory flow reserve near functional residual capacity. A second study (study 2) was conducted in seven asthmatic subjects at control and after three increasing doses of methacholine to compare the pattern of Technegas deposition in the lung with the occurrence of EFL. The latter was assessed at the mouth by comparing tidal with forced expiratory flow or with the flow generated on application of a negative pressure. Study 1 documented enhanced and spotty deposition of Technegas in the central lung regions with increasing radioactivity during tidal expiration. This is consistent with increased impaction of Technegas on the airway wall downstream from the flow-limiting segment. Study 2 showed that both methods based on analysis of flow at the mouth failed to detect EFL at the time spotty deposition of Technegas occurred. We conclude that regional EFL occurs asynchronously across the lung and that methods based on mouth flow measurements are insensitive to it.

Acute renal cortical scintigraphy in children with a first urinary tract infection.

This prospective study, performed in 101 children with a first symptomatic urinary tract infection (UTI), evaluates the diagnostic value of clinical, biological, and ultrasound parameters in detecting children with acute renal infection documented by dimercaptosuccinic acid (DMSA) scintigraphy. In children with a positive DMSA scan, mean C-reactive protein (CRP) was higher than in children with a normal DMSA scan (114+/-64 vs. 67+/-38 mg/dl, mean+/-SD, P=0.0002). The sensitivity and specificity of CRP was 64% and 68%, respectively. In children with severe kidney involvement, mean CRP and white blood count (WBC) were higher than in children with mild/moderate disease (151+/-83 vs. 92+/-55 mg/dl for CRP, P=0.0149; 20,100+/-6,854 vs. 15,023+/-6,145 WBC/ mm3 for WBC, P=0.0131). The sensitivity and specificity was 85% and 20% for CRP, and 77% and 18% for WBC, respectively. One or more areas of abnormal cortical echogenicity were documented in 3% of kidneys with positive DMSA scans. Dilatation of the collecting system was observed in 24% of kidneys. The sensitivity and specificity of ultrasonography was 27% and 89%, respectively. In conclusion, clinical, biological, and ultrasound parameters do not accurately distinguish cystitis from pyelonephritis in children with UTI and do not identify children with severe renal damage. Accordingly, we recommend that DMSA scan should be added to the initial work-up of children with UTI.

Indium-111 labelled white blood cell scintigraphy in cranial and spinal septic lesions.

Cranial and spinal infections are severe events that require timely diagnosis and treatment. Physical and neurological examination, laboratory tests and radiological imaging may be insufficient for assessing cranial and spinal septic lesions. This study aimed to evaluate the accuracy of indium-111 white blood cell (WBC) scan in assessing the presence of leucocytes in intracranial and spinal lesions, and in the diagnosis, management and follow-up of primary, post-traumatic and post-surgical infections. One hundred and twenty-four subjects were included in the study (48 with post-traumatic or post-surgical lesions, 73 with primary cerebral lesions, and 3 with spinal lesions). All patients underwent a diagnostic work-up including planar scans with 111In-labelled WBCs, at 4 and 24 h post tracer injection. All subjects underwent surgical treatment. Patients who did not recover from the infection as suggested by clinical evolution underwent further treatment (up to three times) and further WBC scans (up to four times). WBC scintigraphy correctly identified all the areas of leucocyte accumulation, as confirmed after surgery. WBC scintigraphy also correctly excluded the presence of leucocytes in all other lesions, as demonstrated at surgery. The results of this study confirm the accuracy of WBC scan for the assessment of patients with cranial and spinal lesions, in whom the demonstration of leucocyte accumulation can ease the diagnosis of infection, and indicate that the method is also accurate for the follow-up and management of neurosurgical patients.

Sentinel node mapping for malignant melanoma.

Sixty-seven patients with malignant melanomas were seen in our institute since 1998. We looked for a sentinel node in 26 (38%) patients with lesions thicker than 1 mm, employing a double technique: staining with methylene blue and gamma probe mapping after injection of 99mTc. Forty-six nodes were retrieved, 25% of them containing tumor cells. This approach enabled us to choose between a wait-and-see policy and radical surgery.

Estimation of glomerular filtration rate using chromium-51 ethylene diamine tetra-acetic acid and technetium-99m diethylene triamine penta-acetic acid.

Simultaneous measurements of the clearance rate of chromium-51 ethylene diamine tetra-acetic acid (51Cr-EDTA) and technetium-99m diethylene triamine penta-acetic acid (99mTc-DTPA) were performed in 54 patients with a range of function between 9 and 176 ml/min. Using multiple blood samples the two clearance values correlated well (r = 0.97, SEE 8.6 ml/min) and DTPA clearance was higher by 2.9%. For each radiopharmaceutical the plasma clearance rates obtained using multiple blood samples were compared with those obtained with simplified methods, i.e., the 60-180 min two-sample method of Russell and the mono-exponential method with the Brochner-Mortensen correction. For both radiopharmaceuticals the clearance values correlated well with the Russell method (r = 0.99, SEE = 4.1 ml/min for EDTA; r = 0.99, SEE 4.9 ml/min for DTPA) and the mono-exponential method (r = 0.99, SEE 3.6 ml/min for EDTA; r = 0.99, SEE 3.9 ml/min for DTPA). The mean plasma clearance obtained using multiple blood samples did not differ significantly from that obtained with the Russell method, either in patients with a glomerular filtration rate (GFR) < 30 ml/min or in patients with GFR > or = 30 ml/min. The mean plasma clearance obtained using multiple blood samples differed significantly from that obtained with the mono-exponential method because of the great difference observed in patients with GFR > or = 30 ml/min. It is concluded that the Russell two-sample method after injection of 99mTc-DTPA is accurate enough for routine clinical use.

Cutaneous, musculoskeletal and bone flow scintiscan by intravenous infusion of 99mTc-MDP (Diphosphonate) in the evaluation and control of patients treated with spinal cord stimulation for ischaemic pain.

In patients affected by unbearable pain secondary to peripheral vascular disorders beyond surgical repair such as thromboangitis obliterans, diabetic microangiopathy, arteriosclerosis obliterans, there is a need to establish the degree of micro-circulation functionality before proceeding with invasive pain therapy, such as Spinal Cord Stimulation (SCS). From our series some cases of refractory ischaemic pain subjected to nuclear medicine techniques assessment before and after SCS implant will be presented; these data suggest that the use of radionuclides for quantifying regional perfusion, in view of the information it offers us both in the dynamic angiographic phase and in the later static phase, constitutes a very valid aid in the diagnosis and treatment of chronic pain conditions of ischaemic origin. Cutaneous, musculoskeletal and bone flow scintiscan is a non-invasive procedure which allowed us to make an objective selection of patients who are candidates for prolonged conservative treatment thus limiting the incidence of ineffective permanent SCS implants.

Variations in regional cerebral blood flow investigated by single photon emission computed tomography with technetium-99m-d, l-hexamethylpropyleneamineoxime = l-h during temporary clipping in intracranial aneurysm surgery: preliminary results.

Single photon emission computed tomography with technetium-99m-d, l-hexamethylpropyleneamineoxime was used to assess variations in regional cerebral blood flow during temporary clipping in the course of intracranial aneurysm surgery and during the postoperative period in 20 patients, 14 of whom underwent temporary clipping. Of these 14 patients (Group A), 9 had aneurysms of the anterior communicating artery, 2 had aneurysms of the middle cerebral artery, and 3 had aneurysms of the carotid siphon. Temporary clips were applied, according to the site of the lesion, on A1, on the trunk of the middle cerebral artery, or on the trunk of the internal carotid artery. The occlusion time ranged from 2 to 31 minutes. The six patients who did not undergo temporary clipping served as controls (Group B), as follows: three had aneurysms of the posterior communicating artery, one of the anterior communicating artery, one of the middle cerebral artery, and one of the internal carotid artery. All patients were investigated with cerebral single photon emission computed tomography preoperatively, perioperatively, and postoperatively. In all the patients of Group A, the preliminary results of the study show a sharp fall in the perfusion of the territories of the temporarily clipped parent vessel and practically a complete recovery within 2 to 7 days of surgery, with no significant neurological symptoms. No similar disturbance of perfusion was found in the patients of Group B.

[A study of the variations in myocardial perfusion induced by systemic thrombolysis in acute myocardial infarct using sequential scintigraphy with 201-thallium]. / Studio delle variazioni di perfusione miocardica indotte dalla trombolisi sistemica nell'infarto miocardico acuto mediante scintigrafia sequenziale con tallio 201.

To assess scintigraphic changes induced by intravenous streptokinase therapy, serial rest redistribution thallium-201 perfusion imaging was performed in 62 patients with acute myocardial infarction lasting less than 6 hours. Twenty-seven patients randomized to treatment with intravenous streptokinase (group A) and 35 to conventional therapy (group B) underwent thallium-201 scintigraphy as soon as possible after admission to the coronary care unit (early study). Regional myocardial perfusion was assessed using thallium-201 scintigraphy 7-9 days later in each patient (late study). The size of the perfusion defect was evaluated using a semi-quantitative score. The size of the perfusion defect decreased in serial scans in both group A (preintervention score: 12.1 +/- 6.8; redistribution score: 11.4 +/- 6.8; late study: 8.8 +/- 7.0) and group B (12.8 +/- 6.5; 12.3 +/- 6.7; 10.6 +/- 7.5, respectively). No statistical difference in myocardial perfusion was found between the two groups, on late study. Peak serum creatine kinase MB (CKMB) was earlier in group A than in group B (1030.8 +/- 326.6 vs 1361.0 +/- 271.1: p less than 0.001). The fast CKMB release group (onset of symptoms-peak of CKBM less than or equal to 900 minutes) exhibited higher thallium-201 uptake when compared to the slow CKMB release group, at the time of late study (perfusion defect score: 6.1 +/- 5.7 vs 10.7 +/- 7.3: p = 0.03). Reversibility was observed in 21/62 patients (34%). Reversibility corresponded to unchanged or improved perfusion defect score on late study in 18/21 patients (86%). Nevertheless 20/41 (49%) patients not showing redistribution of thallium-201 within pre-treatment defect had an improvement in regional perfusion on late study. Reversibility was observed in 9/14 (64%) patients with fast CKMB release and in 12/47 (26%) patients with slow CKMB release. We conclude that the early peak of CKMB is associated with a higher uptake of thallium-201 on late study. Furthermore, the reversibility of perfusion defect on redistribution imaging forecasts evolution of scintigraphic perfusion, but, when this is not present, it doesn't rule out late improvement of thallium-201 myocardial uptake. The low sensitivity and specificity of redistribution imaging and the procedure related delay in instituting therapy make thallium-201 scintigraphy unreliable in the evaluation of myocardial reperfusion following thrombolysis.

[Heterotopic autotransplant of the spleen after splenectomy in traumatic rupture. Personal experience and scintigraphic follow-up]. / L'autotrapianto eterotopico di milza dopo splenectomia per rottura traumatica. Esperienza personale e follow-up scintigrafico.

Certain aspects of OPSI (Overwhelming Post-Splenectomy Infection) are examined, mainly its considerable gravity, its relatively high incidence, especially in children; its difficult prophylaxis with a report on personal experience of ectopic autotransplant of spleen tissue in two young patients after splenectomy for traumatic rupture. The technique was found to be simple and quickly performed. Scintigraphic follow-up for over 4 years after the operation showed satisfactory growth in the transplanted spleen tissue.

Single photon emission computed tomography with 99mTc HM-PAO in the study of focal epilepsy.

We used 99mTc HM-PAO SPECT to study 50 patients with partial epilepsy: 47 interictally and 3 during a seizure. All 3 patients studied during a seizure presented an area of increased tracer uptake. Of those in whom recordings were taken during seizure-free intervals 35 (74%) showed perfusion asymmetries: 27 (57%) with decreased and 8 (17%) with increased uptake. We discuss the findings and compare them with those of similar studies using SPECT and positron emission tomography.

Cerebral scintigraphy with 111indium oxine-labelled leukocytes in the differential diagnosis of intracerebral cystic lesions.

CT scanning and scintigraphy with 111Indium-oxide-labelled white blood cells were used to study 32 cases of intracerebral cystic lesions. The results and the criteria of positivity used to lower the false positive rate are discussed. A new criterion, designed to assess the time course of the scintiscan and so reduce still further the frequency of false positives is put forward.

Differential diagnosis of CT-hypodense cranial lesions with indium-111-oxine-labeled leukocytes.

Scintigraphy using indium-111-oxine-labeled white blood cells was used as a complementary diagnostic study in the differential diagnosis of 20 intracerebral cystic lesions for which computerized tomography scanning did not exclude abscess. To lower the rate of false-positive findings with scintiscanning, three criteria of positivity were tested in the 20 lesions. The most stringent criterion yielded 100% sensitivity, 94% specificity, and 96% diagnostic accuracy. The clinical and surgical implications of these results are discussed.