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Background Lymphedema is due to dysfunction of the lymphatic system. It can be primary or secondary. Pediatric lymphedema is more often primary and is a chronic disease with a heavy burden on quality of life. Methods Medical records of patients under 18 years of age referred between 1996 and 2021 to the specialized lymphedema clinic at the Sainte-Justine University Hospital Center were reviewed. Demographic data, sex, age at presentation, location of the lymphedema, clinical features, genetic testing, symptoms, complications, investigations, and treatment were collected. Results Of 180 referred patients, lymphedema was confirmed in 151, and 137 were primary lymphedema. Median age of apparition of primary lymphedema was 7.00 years and was significantly lower in boys than in girls. Primary congenital lymphedema was more frequent in boys (51.0%, 27.3% in girls, P = .007), and onset of primary lymphedema during adolescence was more frequent in girls (53.4%, 25.0% in boys, P = .001). Lower limbs were the most impacted (88.3%). Sixty patients had genetic testing, and 38 (63.3%) of them were discovered to have a pertinent genetic mutation. The most common mutated gene was the FLT4 gene (in 9 patients). Seven patients (5.1%) had associated extensive/central lymphatic malformation and 24 (17.6%) had a polymalformative syndrome/syndromic lymphedema. Conclusions Pediatric lymphedema is more frequent in girls, usually involves lower limb, and is most often sporadic, but often associated with a genetic mutation, and genetic testing should be performed.

Gray zone lymphoma is an aggressive disease for which appropriate management is still debated. We report a 15-year-old girl with a cervical mass, an enlarged ipsilateral tonsil, and anemia. Both sites showed hypermetabolism on F18-FG positron emission tomography/CT. Surgical resection was diagnostic of Epstein-Barr virus-negative gray zone lymphoma cervical and tonsillar involvement. No abnormality was found in cytogenetic analysis on tumor cells. However, exome sequencing in peripheral blood DNA revealed a germline mutation in TP53. Complete response was achieved after surgery and 6 cycles of rituximab with dose-adjusted etoposide, prednisone, vincristine, cyclophosphamide, and doxorubicin regimen.

OBJECTIVE In an attempt to improve postsurgical seizure outcomes for poorly defined cases (PDCs) of pediatric focal epilepsy (i.e., those that are not visible or well defined on 3T MRI), the authors modified their presurgical evaluation strategy. Instead of relying on concordance between video-electroencephalography and 3T MRI and using functional imaging and intracranial recording in select cases, the authors systematically used a multimodal, 3-tiered investigation protocol that also involved new collaborations between their hospital, the Montreal Children’s Hospital, and the Montreal Neurological Institute. In this study, the authors examined how their new strategy has impacted postsurgical outcomes. They hypothesized that it would improve postsurgical seizure outcomes, with the added benefit of identifying a subset of tests contributing the most. METHODS Chart review was performed for children with PDCs who underwent resection following the new strategy (i.e., new protocol [NP]), and for the same number who underwent treatment previously (i.e., preprotocol [PP]); ≥ 1-year follow-up was required for inclusion. Well-defined, multifocal, and diffuse hemispheric cases were excluded. Preoperative demographics and clinical characteristics, resection volumes, and pathology, as well as seizure outcomes (Engel class Ia vs > Ia) at 1 year postsurgery and last follow-up were reviewed. RESULTS Twenty-two consecutive NP patients were compared with 22 PP patients. There was no difference between the two groups for resection volumes, pathology, or preoperative characteristics, except that the NP group underwent more presurgical evaluation tests (p < 0.001). At 1 year postsurgery, 20 of 22 NP patients and 10 of 22 PP patients were seizure free (OR 11.81, 95% CI 2.00–69.68; p = 0.006). Magnetoencephalography and PET/MRI were associated with improved postsurgical seizure outcomes, but both were highly correlated with the protocol group (i.e., independent test effects could not be demonstrated). CONCLUSIONS A new presurgical evaluation strategy for children with PDCs of focal epilepsy led to improved postsurgical seizure freedom. No individual presurgical evaluation test was independently associated with improved outcome, suggesting that it may be the combined systematic protocol and new interinstitutional collaborations that makes the difference rather than any individual test.

Pancreatic neoplasm is very rare in the pediatric population. Malignant tumors represent less than 0.2% of pediatric cancer-related mortality. Pancreas lesions can be from exocrine or endocrine origin or present themselves as cystic masses. Clinical, biological, and radiological findings usually are sufficient to establish diagnosis, but in some cases, they may be misleading. We present the case of a young patient presenting a pancreatic mass where anatomical and metabolic characteristics of the lesion were discordant to the final diagnosis.

Summary Introduction and objective The value of diuretic renography drainage times in congenital hydronephrosis (AHN) decision making is controversial. Recently, a group suggested a modification to the classically described diuretic drainage time cut-off values. They found that a drainage half-time (T1/2) Methods We retrospectively reviewed 113 patients, including consecutive pyeloplasties for AHN from 2004 to 2018. Patients who underwent pyeloplasty due to low differential renal function (DRF) Results The pyeloplasty group consisted of 62 patients and the control group consisted of 51 patients. Two patients (3%) in the pyeloplasty group had a T1/2 75 min (p 75 min (P 75 min demonstrated 100% specificity and 34% sensitivity. Analysis of the GWO using a ROC curve revealed that a cut-off of 50% GWO has 100% specificity and 52% sensitivity for pyeloplasty. Overall, a T1/2 > 75 min or GWO Discussion The limitations of the present study include its retrospective nature. Secondly, the lack of a gold standard diagnostic test for uretero-pelvic junction obstruction hampers objective quantification of diagnostic test utility performance. Conclusions We confirm the utility of the modified diuretic half-time criteria and delayed gravity assisted imaging. A T1/2 > 75 min or GWO 90% is reassuring. Gravity assisted delayed imaging can be especially helpful in cases with indeterminate T 1/2 times and should be included in the standard assessment of hydronephrotic kidneys. These parameters can be used to tailor the frequency and invasiveness of imaging within observation protocols. Download : Download high-res image (173KB) Download : Download full-size image Summary Figure A . Ability of the modified drainage criteria to predict pyeloplasty.

Tuberculosis (TB) remains a major health problem, affecting approximately one-third of the world׳s population. The tubercle bacillus can affect virtually any organ of the human body and if left untreated can lead to severe morbidity and death. Diagnosis of active TB is challenging, especially in children. As a "great imitator," the disease can mimic numerous other pathologies, both clinically and at imaging. Although recognition of active TB is crucial to initiate adequate treatment in a timely fashion, thereby preventing transmission of disease, differentiation of active and quiescent disease is not always straightforward. Since the first reports more than 20 years ago, FDG-PET/CT imaging has been shown to detect active disease with accuracy equal or superior to other conventional imaging modalities. The role of FDG-PET in evaluating patients with TB is rapidly expanding. FDG-PET/CT can effectively identify foci of intrathoracic and extrathoracic TB, assess disease activity, differentiate between active and latent disease, monitor response to therapy, identify potential biopsy targets, and serve as a surrogate end point for new drug trials. Efficacy of FDG-PET/CT in the especially challenging pediatric population will be the focus of this review.

Hemangioendotheliomas are a heterogeneous group of vascular neoplasm that may affect the liver, bone, and soft tissues. Among its variants, pseudomyogenic hemangioendothelioma is rarely encountered. Pseudomyogenic hemangioendothelioma is usually characterized by multiple soft tissue lesions, with occasional bone lesions. Fewer than 20 cases with exclusive involvement of bone structures have been reported. We describe a case of pseudomyogenic hemangioendothelioma involving multiple bony structures but without soft tissue involvement in a 7-year-old girl, imaged with F-FDG PET/CT at diagnosis and during treatment with mammalian target of rapamycin inhibitors.

Introduction: To consider alternative mechanisms that give rise to a refluxing uretero-vesical junction (UVJ), we hypothesized that children with a common heritable urinary tract defect, vesico-ureteric reflux (VUR), may have a defect in the extracellular matrix composition of the UVJ and other tissues that would be revealed by assessment of the peripheral joints. Hypermobile joints can arise from defects in the extracellular matrix within the joint capsule that affect proteins, including Tenascin XB. Methods: We performed an observational study of children with familial and non-familial VUR to determine the prevalence of joint hypermobility, renal scarring, and DNA sequence variants in Tenascin XB. Results: The majority of children, 27/44, exhibited joint hypermobility using the Beighton scoring system. This included 15/26 girls (57.6%) and 12/18 boys (66.6%), which is a significantly higher prevalence for both sexes when compared to population controls (p

FDG PET/CT is emerging as a new tool for the evaluation of acute encephalitis (AE). However, to date, there are no exclusively pediatric studies on the use of FDG PET for suspected AE. The objective of this study was to compare qualitative and quantitative brain PET to conventional brain imaging in a cohort of children, and to identify patterns of metabolic abnormalities characteristic of AE. This retrospective study included 34 children imaged with PET/CT, CT and magnetic resonance imaging (MRI). The positivity rate of all three imaging modalities was measured. Besides visual assessment, quantification of relative regional brain metabolism (RRBM) was performed and compared to a database of normal pediatric brains. Fourteen subjects had a clinical diagnosis of autoimmune encephalitis (AIE) or encephalitis of unknown origin (EX), six of anti-N-methyl-D-aspartate receptor (anti-NMDAr) encephalitis, three of Hashimoto’s encephalopathy, three of neurolupus and eight had other subtypes of encephalitis. Quantitative PET was abnormal in 100% of cases, visually assessed PET in 94.1% of subjects, MRI in 41.2% and CT in 6.9%. RRBM quantification demonstrated multiple hyper and hypo metabolic cortical regions in 82.3% of subjects, exclusively hypermetabolic abnormalities in 3%, and exclusively hypometabolic abnormalities in 14.7%. The basal ganglia were hypermetabolic in 26.5% of cases on visual assessment and in 58.8% of subjects using quantification. In our pediatric population FDG PET was more sensitive than conventional imaging for the detection of AE, and basal ganglia hypermetabolism was frequently encountered.

Background: Little objective pediatric data exist to guide the optimal time needed to achieve thyroid-stimulating hormone (TSH) levels ≥30 μIU/mL prior to performing 131I or 123I whole-body scan (WBS) imaging in children with thyroid cancer in the post-thyroidectomy period or after hormone discontinuation. Methods: Retrospective study of patients aged 5-19 years who underwent WBS. Patient data collection included type and duration of withdrawal (liothyronine [L-T3], levothyroxine [L-T4], or post-thyroidectomy status without hormonal replacement) and TSH measured prior to WBS (level and timing). Results: A total of 175 TSH level measurements were performed in 68 patients. Thirty-five TSH values were obtained 2-7 weeks postoperatively and 101 values were obtained 2-8 weeks post L-T4 withdrawal. One patient in each group had a TSH level p = 0.14) or post L-T4 cessation (p = 0.21). Thirty-nine TSH measurements were obtained 1-28 days post L-T3 withdrawal. Three patients had to be rescheduled due to inadequate TSH levels, including one after 14 days L-T3 withdrawal. Conclusion: TSH levels ≥30 μIU/mL were achieved at 3 weeks post thyroidectomy or after L-T4 withdrawal and after at least 2 weeks following L-T3 cessation.

We present a case of a 15-year-old male with primary bone lymphoma who was initially referred for suspicion of chronic osteomyelitis of the mandible. A bone scan and gallium scan demonstrated congruent uptake in the mandible, suggestive of chronic osteomyelitis. A biopsy subsequently showed B-cell lymphoma of the bone with low Ki-67. A fluorodeoxyglucose positron emission tomography (FDG-PET) scan performed before therapy for staging revealed no increased uptake in the mandible. This case shows an atypical presentation of a rare disorder and is presented to emphasize the importance of baseline FDG-PET.

Acquired demyelinating syndromes include acute disseminated encephalomyelitis, transverse myelitis and may progress to multiple sclerosis (MS). Acute disseminated encephalomyelitis is characterized by impairment of level of consciousness and multifocal neurological deficits and transverse myelitis by back pain, weakness and sphincter dysfunction. Only a few cases of acquired demyelinating syndrome have been imaged with F-FDG PET/CT. We present two such cases.

In the pediatric setting, lymphoscintigraphy is used mostly for the evaluation of lymphedema. Only a few cases of chylous anomalies and lymphatic malformations imaged with lymphoscintigraphy have been reported in the literature. The aim of this study was to review the use of lymphoscintigraphy in those pathologies. Methods: All lymphoscintigraphy studies performed for chylous anomalies between 2001 and 2017 in our hospital were retrospectively reviewed. The results were correlated to clinical and radiologic findings. Lymphoscintigraphy consisted of sequential imaging after injection of 3.7-9.25 MBq (100-250 μCi) of 99mTc-filtered sulfur colloid at the level of the feet or hands. Results: Twenty-five studies were performed on 21 patients. Fourteen studies were obtained for the evaluation of chylothorax. Eleven were performed for chyloperitoneum, chyluria, chylopericardium, exudative enteropathy, or lymphangiomatosis. Ten studies were positive for lymphatic leakage, and 1 had uncertain results. After correlation with radiologic findings and follow-up, there were 7 true-negative and 5 false-negative results (previous 67Ga-interfering activity in 1, injection in only the hands in 3, and a low-fat diet in 1). One study became positive after injection in the feet, and another became positive after a switch to a high-fat diet. Conclusion: Lymphoscintigraphy is a useful tool for imaging lymphatic anomalies in children. Suggestions to optimize results include placing the patient on a high-fat diet, withholding octreotide, injecting the 4 extremities, and imaging with SPECT/CT.

Reference databases of pediatric brain metabolism are uncommon, because local brain metabolism evolves significantly with age throughout childhood, limiting their clinical applicability. The aim of this study was to develop mathematic models of regional relative brain metabolism using pediatric

Aims: Increased 18F-fluorodeoxyglucose uptake within active brown adipose tissue (BAT) on an 18F-fluorodeoxyglucose PET/CT study is a known pitfall that has been well described in the literature. We have noted a similar phenomenon occurring in gallium-67 studies performed on neonates, which introduces an undesirable element of complexity when evaluating for the presence of infection or malignancy. Since the incidence of gallium-67 uptake in BAT in neonates has not been previously described in the literature, the goal of this study was to evaluate the pattern of uptake and its incidence in our neonatal patient population. Materials & methods: A complete review was performed of the Hospital Ste-Justine's (QC, Canada) database of nuclear medicine studies carried out from June 2001 to May 2011, revealing 64 total body gallium-67 scans of neonates (carried out within the first 28 days after birth). These studies were reviewed for BAT gallium-67 uptake. Results: Ten of out 64 patients had gallium-67 uptake in a...

Little objective pediatric data exist to guide the optimal time needed to achieve thyroid-stimulating hormone (TSH) levels ≥30 μIU/mL prior to performing 131I or 123I whole-body scan (WBS) imaging in children with thyroid cancer in the post-thyroidectomy period or after hormone discontinuation.Retrospective study of patients aged 5-19 years who underwent WBS. Patient data collection included type and duration of withdrawal (liothyronine [L-T3], levothyroxine [L-T4], or post-thyroidectomy status without hormonal replacement) and TSH measured prior to WBS (level and timing).A total of 175 TSH level measurements were performed in 68 patients. Thirty-five TSH values were obtained 2-7 weeks postoperatively and 101 values were obtained 2-8 weeks post L-T4 withdrawal. One patient in each group had a TSH level30 μIU/mL. There was no difference in TSH levels between 3 weeks and 4 weeks postoperatively (p = 0.14) or post L-T4 cessation (p = 0.21). Thirty-nine TSH measurements were obtained 1-28 days post L-T3 withdrawal. Three patients had to be rescheduled due to inadequate TSH levels, including one after 14 days L-T3 withdrawal.TSH levels ≥30 μIU/mL were achieved at 3 weeks post thyroidectomy or after L-T4 withdrawal and after at least 2 weeks following L-T3 cessation.

H syndrome (OMIM 612391) is an extremely rare autosomal recessive genodermatosis, characterized by extensive skin infiltration. We report a case imaged with F-FDG PET/CT.

Stress myocardial perfusion scintigraphy imaging (SMPSI) has important applications for evaluating coronary disease and ventricular function. Studies consistently focus on the left ventricle (LV), with no normal right ventricle (RV) data available. This study sought to evaluate the feasibility of RV perfusion with technetium (Tc-99m) sestamibi using a low radiotracer dose for children free of coronary artery (CA) anomalies and to determine its normal pattern. Patients with a history of Kawasaki disease who showed no coronary complications on selective angiography or no LV perfusion defects on SMPSI were studied at rest and during an exercise challenge. The RV uptake counts were compared with those for different segments of the LV, and multiple ratios of the uptakes between RV and LV segments were calculated. The study subjects were 23 children (age, 11.1 ± 3.3 years) imaged with 0.12 ± 0.03 mCi/kg at rest and 0.31 ± 0.06 mCi/kg during stress. The RV to LV uptake proportion was approximately 6%. Exercise-related uptake increased threefold in both the RV and the LV. The findings showed RV myocardial scintigraphy to be feasible with reproducible ratios. Potential clinical applications include acquired and congenital CA anomalies such as Kawasaki disease, right CA ostium stenosis after a switch operation, and anomalous origin of the right CA.

La case du tout-petit, un nouveau modele de prise en charge de la petite enfance au Senegal, cotoie depuis 2002 les diverses structures de l’education prescolaire formelle, non formelle et informelle. L’article s’attache a porter un regard particulier sur cette structure dans le cadre de la nouvelle politique dite integree de la petite enfance. L’auteure analyse les conditions d’emergence ainsi que le mode d’organisation et de fonctionnement de cette structure devenue modele de reference pour les autorites publiques senegalaises.

Blastic plasmacytoid dendritic cell neoplasm is a rare malignancy characterized by cutaneous involvement and hematological dissemination. Most affected patients are older, usually in the sixth or seventh decade of life, and this condition has rarely been described in the pediatric population. This report presents the case of a 9-year-old boy with blastic plasmacytoid dendritic cell neoplasm and demonstrates the utility of FDG PET/CT for staging and treatment follow-up.

Background. Cyclosporine A (CyA) and tacrolimus are the principal immunosuppressive agents used for OLT in children. However, progressive deterioration of renal function from calcineurin inhibitor toxicity after OLT has been widely reported. The aim of this study was to assess long-term renal function in children after OLT Methods. We reviewed all OLT patients surviving >1 year at Sainte Justine Hospital from 1987 to 2003. The GFR (ml/min/1.73m 2 ) was measured yearly by the Tc-99m DTPA single injection technique Results. In all, 101 OLT patients (27 tyrosinemia, 33 biliary atresia, 5 fulminant hepatic failure, 36 miscellaneous) were studied. Median age at OLT was 35 months (range 6-178 months) in tyrosinemia group and 58 months (range 1-226 months) in the "Others" (P = NS), median pediatric end-stage liver disease score was respectively 3 (range - 9 to 21) and 15 (-9 to 35), (P= 0.001), and median follow-up was 6 (range 1-14) and 6 (range 1-17) (P = NS) years, respectively. Median annual GFR values in tyrosinemia fluctuated between 61 and 104 ml/min/1.73m 2 , with an improving tendency, and 94-121 ml/min/1.73m 2 in the Others. GFR did not differ on CyA vs. tacrolimus treatment. The median duration of therapy with calcium-channel blocker in the tyrosinemia group was 5 (1-13) vs. 2 (1-13) years in the Others. Conclusions. Median GFR remained normal in most nontyrosinemia patients (Others). Tyrosinemia patients remained stable at a lower GFR. CyA administration in three daily doses and prolonged calcium-channel blocker therapy may have contributed to this stability. Impairment of kidney function was associated with congenital kidney disease, toxic kidney injury, and portal hypertension.

The goal of our study was to compare Doppler sonography and renal scintigraphy as tools for predicting the therapeutic response in patients after undergoing renal angioplasty. SUBJECTS AND METHODS. Seventy-four hypertensive patients underwent clinical examination, Doppler sonography, and renal scintigraphy before and after receiving captopril in preparation for renal revascularization. The patients were evaluated for the status of hypertension 3 months after the procedure. The predictive values of the findings of clinical examination, Doppler sonography, renal scintigraphy, and angiography were assessed.For prediction of a favorable therapeutic outcome, abnormal results from renal scintigraphy before and after captopril administration had a sensitivity of 58% and specificity of 57%. Findings of Doppler sonography had a sensitivity of 68% and specificity of 50% before captopril administration and a sensitivity of 81% and specificity of 32% after captopril administration. Significant predictors of a cure or reduction of hypertension after revascularization were low unilateral (p = 0.014) and bilateral resistive (p = 0.016) indexes on Doppler sonography before (p = 0.009) and after (p = 0.028) captopril administration. On multivariate analysis, the best predictors were a unilateral resistive index of less than 0.65 (odds ratio [OR] = 3.7) after captopril administration and a kidney longer than 93 mm (OR = 7.8). The two best combined criteria to predict the favorable therapeutic outcome were a bilateral resistive index of less than 0.75 before captopril administration combined with a unilateral resistive index of less than 0.70 after captopril administration (sensitivity, 76%; specificity, 58%) or a bilateral resistive index of less than 0.75 before captopril administration and a kidney measuring longer than 90 mm (sensitivity, 81%; specificity, 50%).Measurements of kidney length and unilateral and bilateral resistive indexes before and after captopril administration were useful in predicting the outcome after renal angioplasty. Renal scintigraphy had no significant predictive value.

Endocrinology Service and Research Center (S.S.-V., J.D.), Otorhinolaryngology Department (A.L.), and Nuclear Medicine Service (S.T.), Centre Hospitalier Universitaire Sainte-Justine, Department of Pediatrics, University of Montreal, Montreal, Canada H3T 1C5; and Institut de Recherche Interdisciplinaire en Biologie Humaine et Moleculaire and Genetics Service (C.R., G.V.), Erasme Hospital, Free University of Brussels, B-1070 Brussels, Belgium

Reduced left lung perfusion has been described following percutaneous occlusion of the patent ductus arteriosus (PDA). We aimed to identify the incidence of lung perfusion abnormalities and the associated risk factors in our consecutive series. Between November 1994 and December 2003, 150 procedures were performed on 145 patients, age 4.6 ± 4 years. Gianturco coil was used in 88.2%, Amplatzer duct occluder in 6.7%, and Rashkind Umbrella in 5.5%. Lung perfusion scan was scheduled within 48 h (LPS-1), at 6–12 months (LPS-2) and later (LPS-3) in the case of persistent abnormalities. Left lung perfusion

Clinical findings are still the mainstay for suspecting the diagnosis of musculoskeletal infections, especially osteomyelitis. No single complementary imaging technique has 100% specificity and sensitivity for every case of musculoskeletal infection. Depending on the age of the patient, presence of orthopedic hardware, location of infection, underlying bone, and systemic conditions, the choice of imaging modalities must be tailored to the patient's condition. Plain radiographs are performed first and may be sufficient. In children, bone scan is highly accurate to diagnose osteomyelitis. Labeled leukocytes with complementary bone or bone marrow studies are recommended for orthopedic hardware or diabetic foot. Finally, gallium scanning is useful for the diagnosis of vertebral osteomyelitis. Current radiopharmaceuticals used for diagnosing infection also label inflammation. Newer products, as Infecton, should in the future allow better differentiation between infection and sterile inflammation.

Ga-67 citrate scintigraphy has be used extensively to locate infectious foci. Infections of a synthetic vascular graft is a rare but catastrophic complication of aortobifemoral bypasses. They can be identified on Ga-67 or labeled leukocytes scans. Usually, they are seen as focal, sometimes ill-defined, uptake on Ga-67 scintigraphy. The authors report a case of an extensive aortobifemoral graft infection giving a lambda image in the abdomen

Both dipyridamole and adenosine are widely used as pharmacologic stressors with 201Tl imaging for detection of coronary artery disease. The purpose of this study was to compare dipyridamole and adenosine 201Tl imaging directly in patients with angiographically proved coronary artery disease.Fifty-four patients were submitted to two planar 201Tl studies: one with dipyridamole and the other with adenosine. The interval between the two studies varied from 2 to 7 days and the order was assigned randomly. Three standard planar views were obtained 10 minutes and 4 hours after the injection of 3.0 mCi 201Tl. Administration of dipyridamole was as follows: 0.142 mg/kg/min during 4 minutes, followed by a slight exercise and 201Tl injection. The infusion of adenosine was as follows: 0.140 mg/kg/min during 6 minutes with injection of 201Tl after the third minute of infusion. Patients were asked to give their preference considering the number, type, severity, and duration of side effects on a scale from 0 (worst) to 5 (best). Reading was done by two experienced observers. The heart was divided into three segments per view. The change in systolic blood pressure was -12 +/- 11 mm Hg for adenosine and -5 +/- 10 mm Hg for dipyridamole (p0.001), and the change in heart rate was 18 +/- 10 beats/min for adenosine and 8 +/- 7 beats/min for dipyridamole (p0.001). With regions of interest, ischemic/normal wall ratios were determined: 0.78 +/- 0.06 for adenosine and 0.83 +/- 0.08 for dipyridamole (p0.001). Adenosine detected 295 normal, 170 ischemic, and 21 scar segments, whereas dipyridamole detected 326, 135, and 25 segments, respectively. Patients preferred adenosine (4.3 +/- 1.0 for adenosine vs 3.8 +/- 1.5 for dipyridamole; p0.04) mainly because of the short duration of side effects.This study shows that the use of adenosine with 201Tl imaging may have some advantages over dipyridamole.

The rim sign Is usually associated with a missed testicular torsion. Here, a rim sign was demonstrated during peritoneoscintigraphy, in a case of an indirect Ingulnal hernia. Activity was found not only along the inguinal canal, but also around the testicle due to a large patent processus vaginalis. An intravenous injection of Tc-99m pertechnetate helped evaluate the respective size of the right and left sides of the scrotum.

The aim of this study was to define the use of the triple radiopharmaceutical renal study (TRRS) for renal scintigraphy as a physiological tool for renal evaluation, and to determine if the sensitivity and/or specificity of a renal study for the diagnosis of renovascular hypertension (RVH) could be improved by the combination of three radiopharmaceuticals (i.e., I-131 OIH, Tc-99m DTPA, and Tc-99m glucoheptonate). One hundred ninety-five patients with suspected RVH underwent TRRS, standard Tc-99m DTPA renal studies, and renal angiography. One hundred eighty-nine patients were hypertensive and ischemic nephropathy was suspected in six. Ninety-one, including three patients with ischemic nephropathy, had a renal artery stenosis of 70% or more (66 unilateral, 25 bilateral). Effective renal plasma flow (ERPF), glomerular filtration rate (GFR) (from plasma clearance of I-131 OIH and Tc-99m DTPA), and geometric renal masses (from Tc-99m glucoheptonate study) were compared to normal values corrected for body surface, to determine the severity of renal dysfunction. For the TRSS, RVH criteria included: 1) differential Tc-99m DTPA function minus differential Tc-99m glucoheptonate function of affected kidney ( 5%); and 2) functional parameters: ERPF = 1.6-2.0 ml/g/minute, GFR = 0.25-0.4 ml/g/ minute, and filtration fraction (i.e., GFR/ERPF = 0.15-0.20) on the affected side. For the standard Tc-99m DTPA renogram, two of the following criteria were used for diagnosis of RVH: time to peak (>5 minutes or a difference of more than 1 minute between kidneys), differential uptake ( 25 minutes or a difference of more than 5 minutes). The sensitivities of TRRS and standard Tc-99m DTPA were 77% and 68%, respectively, and the specificities were 83.5% and 68%. Sensitivity was only slightly improved (chi-square test, P < 0.2). However, specificity was significantly higher with TRRS than with standard Tc-99m DTPA (chi-square test, P < 0.01). The combination of the renographic curves and the functional parameters, as done in TRRS, improves sensitivity and mostly specificity, for the detection of renovascular disease. Higher specificity is particularly important in a population with a low prevalence of the disease. As exemplified by this study, TRRS can be a noninvasive test to assess renal physiological parameters, for clinical and research purposes

A 65-year-old woman was evaluated for recurrent right flank pain. She had one episode each decade for 40 years. The findings of repeated excretory urograms were normal. Tc-99m DTPA renograms with furosemide did not reveal obstruction. The renogram was repeated during an acute right flank pain episode and showed right kidney obstruction. A retrograde ureterogram was performed the next day, after the pain had resolved, and was normal. At surgery, an aberrant vessel crossing the ureteropelvic (UP) junction was found. The patient underwent an Anderson-Hynes dismembered pyeloplasty and has been symptom free since.

A 63-year-old woman was admitted for bone pain in her spine and right shoulder. She had been treated previously for medullary carcinoma of the thyroid, associated with MEN2A. Radiographs of her spine and shoulders were normal. Tc-99m MDP bone scan demonstrated diffuse increased uptake in the skeleton, consistent with bone marrow invasion. Neoplastic infiltration by medullary carcinoma of the thyroid was confirmed by bone marrow biopsy. To the authors' knowledge, this is the first case of Tc-99m MDP 'superscan' in medullary carcinoma of the thyroid.

The objective of our study was to compare the value of captopril-enhanced Doppler sonography, captopril-enhanced renal scintigraphy, and gadolinium-enhanced MR angiography for detecting renal artery stenosis.Forty-one patients with suspected renovascular hypertension were prospectively examined with captopril-enhanced Doppler sonography, captopril-enhanced renal scintigraphy, gadolinium-enhanced MR angiography, and catheter angiography. The sensitivity and specificity of each technique for detecting renal artery stenosis measuring 50% or greater and 70% or greater were compared using the McNemar test. Positive and negative predictive values were estimated for populations with 5% and 30% prevalence of renal artery stenosis. Kappa values for interobserver agreement were assessed for both gadolinium-enhanced MR angiography and catheter angiography.For detecting renal artery stenosis measuring 50% or greater, the sensitivity of gadolinium-enhanced MR angiography (96.6%) was greater than that of captopril-enhanced Doppler sonography (69%, p = 0.005) and captopril-enhanced renal scintigraphy (41.4%, p = 0.001). No significant difference in specificity was observed among modalities. For renal artery stenosis measuring 50% or greater, positive and negative predictive values were respectively 62% and 86% for captopril-enhanced Doppler sonography, 49% and 76% for captopril-enhanced renal scintigraphy, and 53% and 98% for gadolinium-enhanced MR angiography. Interobserver agreement was high for both gadolinium-enhanced MR angiography (kappa = 0.829) and catheter angiography (kappa = 0.729).Gadolinium-enhanced MR angiography is the most accurate noninvasive modality for detecting renal artery stenosis greater than or equal to 50%. The use of captopril-enhanced Doppler sonography in combination with gadolinium-enhanced MR angiography for identifying renal artery stenosis needs to be evaluated with a cost-effectiveness analysis.

Renovascular hypertension affects 15%-30% of patients who have clinical criteria suggestive of renovascular disease. Noninvasive screening is crucial for patient selection prior to conventional angiography and renal revascularization. Renal scintigraphy has been reported to be sensitive for detection of renovascular hypertension, but some of its limitations (eg, in the setting of bilateral renal artery stenosis and renal failure) should be considered. Doppler ultrasonography (US) allows direct evaluation of the renal arteries as well as transrenal Doppler waveform analysis, but it remains operator dependent. Gadolinium-enhanced magnetic resonance (MR) angiography is becoming an excellent alternative to conventional angiography. The main limiting factors of this technique are inadequate visualization of segmental and accessory renal arteries as well as a tendency toward overestimation of stenoses. Given the high cost and low availability of MR angiography, scintigraphy and Doppler US should be considered the primary studies in screening for renovascular hypertension. MR angiography could be reserved for patients with inconclusive scintigraphic and Doppler US results, patients with high clinical suspicion of renovascular hypertension, and patients with a contraindication to conventional angiography.