Gastric emptying is accelerated in obese type 2 diabetic patients without autonomic neuropathy.

OBJECTIVE: To clarify the impact of type 2 diabetes mellitus on the gastric emptying rate. MATERIAL AND METHODS: Using a double-isotope scintigraphic technique, we assessed the gastric emptying of a standard liquid-solid meal in 13 obese type 2 diabetic patients without autonomic neuropathy (age: 47.4 +/- 8.6 yr, body mass index: 33.9 +/- 4.8 kg/m(2), glycaemia: 9.1 +/- 2.6 mmol/l) and in 7 controls with similar sex ratio, age, BMI and body fat distribution. RESULTS: The half gastric emptying time for the liquid phase was not significantly different between diabetic patients and controls (respectively: 52.7 +/- 14.5 min and 63.1 +/- 15.2 min). However, the half gastric emptying time for the solid phase was significantly shortened in diabetic patients versus controls (respectively 88.8 +/- 23.2 min in diabetic patients and 113.6 +/- 26.9 min in controls; p<0.04). Furthermore, a negative relationship was highlighted between the half gastric emptying time for the solid phase and basal glycaemia (r=-0.65, p<0.02) in diabetic patients. No significant relationship was found between gastric emptying parameters and cardiac autonomic nerve function, insulin or gastrin levels. CONCLUSION: Solid gastric emptying is accelerated in obese type 2 diabetic patients without patent autonomic neuropathy when compared to obese non diabetic patients.

Detection of subclinical abdominal hernia by peritoneal scintigraphy.

This study investigated the incidence of subclinical abdominal hernia in patients starting peritoneal dialysis (PD). From April 1995 to August 1999, every new patient without clinical evidence of abdominal leakage underwent peritoneal scintigraphy. A total of 59 patients were enrolled in the study. Imaging of the peritoneal cavity was performed by mixing 74 MBq (2 mCi) of 99 m technetium sulfur colloid with 2 L of 1.36% dextrose peritoneal dialysis solution. Sequential gamma camera static images were obtained at 0 minutes, 60 minutes, and after drainage. Ten abdominal hernias (2 diaphragmatic leaks, 8 inguinal hernias) were observed in ten patients (6 males, 4 females; mean age: 65.1 years). One patient with diaphragmatic leak recovered partial renal function and stopped continuous ambulatory peritoneal dialysis (CAPD); the other was switched to automated peritoneal dialysis (APD). Among the eight patients with inguinal hernia, six had no clinical manifestations within eight months of follow-up. Two patients became symptomatic at 15 months and 25 months respectively. They underwent surgical repair. In CAPD patients without obvious abdominal hernias, peritoneal scintigraphy at onset of dialysis discovered 17% positive cases. The technique of scintigraphy is safe, with a low radiation exposure. Surgical repair for maintenance on CAPD is not always necessary, and a change in the PD strategy may be useful.

Thoracic and abdominal SPECT-CT image fusion without external markers in endocrine carcinomas. The Group of Thyroid Tumoral Pathology of Champagne-Ardenne.

UNLABELLED: Superimposition of SPECT and computed tomography (CT) slices from the thoracoabdominal region was achieved without the use of external markers for 14 studies in 13 patients with endocrine carcinoma. Technical feasibility and clinical validation of this retrospective fusion method were assessed. METHODS: Patients had a history of thyroid cancer or of carcinoid tumor. To detect tumor sites, CT scan and dual-isotope tomoscintigraphy were performed, with 99mTc-hydroxymethylene diphosphonate for bone scintigraphy and with 111In-pentetreotide, 131I or 131I-metaiodobenzylguanidine for tumor scintigraphy (TS). A superimposition method previously developed for the pelvic region was adapted to the nonrigid thoraco-abdominal region. CT-bone scintigraphy and CT-TS superimposed images were obtained. Clinical validation of the information obtained from the superimposed images was obtained from surgery or follow-up imaging studies performed after clinical evolution of the disease process. RESULTS: Reliable and reproducible registration was achieved in all patients. CT-TS superimposed images produced accurate localization of abnormal TS foci. Accuracy was limited primarily by variable relative displacements of the thoracoabdominal organs. For 10 sites in 8 patients, localization and/or characterization obtained from CT-TS images was confirmed by a reference technique. Superimposition enabled the localization of tumor sites that otherwise could not have been suspected from CT alone and allowed the characterization of CT suspicious masses and the confirmation of CT positive sites. Nonspecific tumor TS uptake sites were also localized. CONCLUSION: With standard CT and dual-isotope SPECT acquisitions, SPECT-CT fusion is feasible in the thoracoabdominal region without the use of external markers. Fused images were validated in 8 patients for 10 sites. The use of this technique could probably improve the management and care of patients with endocrine carcinoma.

Assessment of radioisotopic micturating cystography for the diagnosis of vesicoureteric reflux in renal transplant recipients with acute pyelonephritis.

BACKGROUND: The gold standard for documenting vesicoureteric reflux is direct (retrograde) micturating cystography (MC). In children, radioisotopic MC has been advocated for increased sensitivity and lesser radiation exposure. In renal transplant recipients, where reflux can induce acute pyelonephritis, this technique has not been evaluated. The aim of this study was to assess the radioisotopic technique in these patients. METHODS: Seventeen renal transplant recipients had developed acute pyelonephritis following the surgical grafting procedure. They were investigated using both MC techniques. Radioisotopic MC was performed using 99mTc-pertechnetate. RESULTS: Reflux was documented in nine patients by radioisotopic MC but in only seven with the conventional technique. All negative patients remained symptom free after the pyelonephritis was cured and it was assumed that they had no reflux. Consequently, using the radioisotopic MC as gold standard, the conventional X-ray technique had a sensitivity of 78% and a specificity of 100%. CONCLUSIONS: Direct radioisotopic MC allowing continuous cystogram recording is more accurate than conventional X-ray MC for the diagnosis of vesicoureteric reflux in transplanted patients with acute pyelonephritis.

Quantitative comparison of prone and supine myocardial SPECT MIBI images.

The myocardial count distribution and the stress/rest ratio distribution were compared between prone and supine Tc-99m MIBI myocardial SPECT acquisitions. Ninety-nine male patients with a low stress supine inferior wall count underwent stress and rest acquisitions in the supine and prone positions successively. For each study, values depicting the inferior, anterior, septal, and lateral wall counts were extracted from a medioventricular normalized circumferential profile and underwent a statistical analysis (Student's paired t-test). On prone imaging, when compared to supine imaging, counts showed a highly significant mean relative increase of 11% +/- 1% in the inferior wall and of 7% +/- 1% in the septum. Conversely, these counts showed a significant mean relative decrease of 4% +/- 1% in the anterior wall and of 3% +/- 1% in the lateral wall. Moreover, the inferior wall stress/rest ratio showed a highly significant mean relative increase (6% +/- 2%). The prone position is probably preferable for interpreting the inferior wall and septum, where relative counts are enhanced, as with TI-201, and because the inferior stress-rest discrepancies are reduced in that position. But the anterior and lateral wall information is impaired in the prone position. The authors suggest, in case of a low stress supine inferior count, the combination of both positions, which is feasible with Tc-99m MIBI, in order to prevent a misleading interpretation.

Low-dissipation tunable rf preamplifier for low temperature NMR applications.

We describe a simple circuit which can be used as an impedance matching device to improve the S/N ratio when lossy cables must be used in low-temperature NMR experiments. The total dissipation is less than 2 mW and the circuit operates satisfactorily down to 1.5 K. The only tuned circuit is the nuclear resonance circuit which incorporates GaAs (P) diodes which can be tuned remotely.