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AimTo evaluate kidney function before and after surgical correction of vesicoureteral reflux. The long-term effect was measured with quantitative nephro-scintigraphy using 99Tcmlabelled dimercaptosuccinic acid (99Tcm-DMSA).MethodsForty-five children with a history of urinary tract infections due to vesicoureteral reflux (VUR) were studied. VUR grade was determined with contrast voiding cystourethrography. Planar scintigraphy was performed with 99Tcm-DMSA and uptake measured as a percentage of injected dose. Kidney function was evaluated at baseline and 5 years after corrective surgery.ResultsThree months after surgery, persistent mild reflux was found in eight of 76 treated renal units. Kidney uptake at 5-year follow-up was unchanged in the majority of children, indicating preservation of renal function found at baseline. The split renal function showed an excellent correlation (r0.99) between baseline and follow-up studies (regression slope 1.01). Percentage uptake had a regression slope of 0.89 significantly different from unity (P<0.05). Empirical kidney-depth correction techniques were compared. The scintigraphic pattern worsened in six kidneys, indicative of increased scarring in a minority of children.ConclusionPlanar nephro-scintigraphy with 99Tcm-DMSA was well tolerated in our paediatric population, and appeared appropriate to evaluate kidney function in time. After surgical correction of VUR, the baseline function was maintained in 94 of kidneys.

Abstract: Positron emission tomography (PET) with 18F-fluoride was utilized to determine the regional blood flow to the femoral head in early osteonecrosis. Five patients with a history of unilateral hip trauma and a normal contralateral side were selected. Skeletal flow and fluoride uptake in the abnormal and normal hips were compared directly, and the relation between bone blood flow and final outcome, i.e., surgical replacement or conservative treatment, was evaluated. In this pilot study, a flow ratio of at least 2 between the abnormal and normal femoral head was necessary to predict a successful outcome with a conservative regimen. A minimum flow of 0.04 ml/min/ ml was measured in one patient whose affected femoral head healed conservatively. Our preliminary study indicates that this type of highly technical investigation appears feasible in clinical practice and permits prediction of the outcome depending upon regional skeletal flow measurements in vivo.

An increased free thyroxine (T4) index was observed in 73% of 33 consecutive pregnancies complicated by severe hyperemesis gravidarum. The free triiodothyronine (T3) index was increased in only four of 11 hyperthyroxinemic patients. In five hyperthyroxinemic patients tested, no increase in serum thyrotropin was observed after the injection of thyrotropin-releasing hormone (TRH). Goiter, exophthalmos, or previous history of hyperthyroidism was absent in all patients. The thyroxinemia returned to normal in one to several weeks, whether or not it was treated with antithyroid drugs. The thyroid function during the period of hyperemesis had no influence on the subsequent rate of abortion or duration of pregnancy. A lower birth weight, however, was observed in children born to hyperthyroxinemic mothers. Hyperemesis gravidarum should be included in the differential diagnosis of elevations in free T4index during pregnancy and included in the differential diagnosis of hyperthyroidism.

Abstract: By deconvolving the activity/time curves obtained from the blood and kidney, the renal retention function can be calculated, yielding useful clinical data. However, the current deconvolution techniques are not very reliable; they are sensitive to the inaccuracies present in the data. A more reliable, stable and efficient deconvolution technique based on the singular value decomposition, total linear least squares (TLLS), is proposed and its properties are described. The applicability of TLLS as a deconvolution technique in renography is discussed and demonstrated. Results from simulation, as well as from clinical data, are presented to show the advantages of the use of TLLS with respect to noise rejection in the data. They confirm the superiority of TLLS over the current deconvolution techniques. It is concluded that TLLS needs no smoothing and is a powerful, efficient, reliable and stable deconvolution technique.

S-Benzyl-, S-benzamidomethyl- and S-benzoylmercaptoacetyltriglycine were synthesized and compared in exchange labelling experiments for the preparation of 99mTc-MAG3. The rate of exchange from 99mTc-tartrate to 99mTc-MAG3 starting from the respective precursors was determined in different conditions. Labelling proceeded most rapidly starting from the S-benzoyl protected precursor but efficient labelling was also accomplished using the more stable S-benzamidomethyl- and S-benzylmercaptoacetyltriglycine. 99mTc-MAG3 was also prepared by direct labelling of unprotected mercaptoacetyltriglycine at alkaline pH. Radiochemical purity in these conditions is mainly dependent on the pH during labelling.

We analyse the Dyson-Schwinger equations of the photon and electron propagator of massless QED3. Although the perturbation expansion in this theory contains infrared divergences, the Dyson-Schwinger equations admit well-defined solutions. Perturbative infrared divergences are replaced, in the solutions of the Dyson-Schwinger equations, by new parameters, which are matrix elements of field operators. The full electron propagator is shown to depend crucially on the effective photon mass 〈AμAμ〉.We point out the relevance of our approach to the analysis of Dyson-Scwinger equations in other theories.

Patients with T3/T4 rectal cancers were injected i. v. with 400–555 MBq F–18 FDG. Dynamic imaging was immediately started. Maximum tumor glucose utilization was calculated. Cell kinetics were measured by flow cytometry 6–8 hrs after i. v. injection of IUdR.Two groups of patients were studied: 1) surgery only (n=8); and 2) preoperative radiotherapy (30 Gy/10 fractions) followed by surgery (RT, n=6). At baseline, TuGluc for group I was 280±141 (SD) nmo1/min/ml, and for group 2:269±161 (P=NS). After RT, TuGluc decreased to 109±61 (P0.05). T pot was 3.50±1.21 days for group I and 3.23±2.23 days for group 2 before RT (P=NS). A negative correlation was found between TuGluc and Tpot, suggesting increasing glucose utilization for faster dividing cells. After RT, Tpot did not change significantly (4.88±3.80 days), whereas TuGluc fell significantly.

This report describes the diagnostic contribution of gallium-67 scintigraphy in 145 cases of fever of unknown origin (FUO) at University Hospital in Leuven, Belgium, in 1980–1989. A final diagnosis was established in 99 (68%) of the 145 cases. Sixty-three scans (43%) were normal, and 82 (57%) were abnormal; only 42 of the abnormal scans (29% of the total number of scans) were considered helpful in diagnosis. Thus 49% of the abnormal scans were considered noncontributory to the diagnosis. In the same population, 15 (6%) of 266 ultrasonograms and 32 (14%) of 233 computed tomograms were helpful in diagnosis. We conclude that gallium scintigraphy remains a valuable screening tool in the investigation of FUO: it yielded diagnostic information in 29% of cases in which the probability of a definitive diagnosis was only 68%. We suggest the use of gallium scintigraphy as a second-step (as opposed to a last-resort) procedure in the evaluation of FUO.

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