Sophie Turpin - Academia.edu (original) (raw)

Papers by Sophie Turpin

Research paper thumbnail of Comparison of Early and Delayed Scintigraphy with 99mTcApcitideand Correlationwith Contrast-EnhancedVenographyin Detection of Acute Deep Vein Thrombosis

Research paper thumbnail of Imaging of renovascular hypertension: Respective values of renal scintigraphy, renal Doppler US, and MR angiography

Radiographics

Renovascular hypertension affects 15%-30% of patients who have clinical criteria suggestive of re... more 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.

Research paper thumbnail of Metastatic axillary lymph node technetium-99m-MIBI imaging in primary breast cancer

Journal of Nuclear Medicine

Technetium-99m-MIBI scintimammography has been shown to be useful in the detection of primary bre... more Technetium-99m-MIBI scintimammography has been shown to be useful in the detection of primary breast cancer. The purpose of this study was to evaluate the potential role of scintimammography in detecting axillary lymph node involvement in patients undergoing scintimammography to detect primary breast cancer. A group of 100 women with breast cancer who were scheduled for a Level I-II axillary dissection were prospectively studied. Scintimammography was performed in all patients before histopathologic confirmation of breast cancer. Two lateral (prone imaging) views and one anterior (supine) planar thoracic view were obtained 10-15 min after the injection of 25-30 mCi 99mTc-MIBI (10 min/view) by using a special breast positioning device (foam cushion) placed over the imaging table. Both of the axilla were included in the field-of-view. Two experienced blinded observers reviewed all cases both from films and from the computer screen with contrast adjustment when needed. The site of intr...

Research paper thumbnail of Detection of renal artery stenosis: prospective comparison of captopril-enhanced Doppler sonography, captopril-enhanced scintigraphy, and MR angiography

AJR. American journal of roentgenology, 2001

The objective of our study was to compare the value of captopril-enhanced Doppler sonography, cap... more 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 th...

Research paper thumbnail of Technetium-99m-sestamibi prone scintimammography to detect primary breast cancer and axillary lymph node involvement

Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1995

The purpose of this study was to evaluate prospectively the sensitivity and specificity of scinti... more The purpose of this study was to evaluate prospectively the sensitivity and specificity of scintimammography in the detection of both primary breast cancer and axillary lymph node involvement. Sixty-five consecutive women referred for a suspicious breast lesion on clinical examination and/or with abnormal mammographies suggestive of malignancies were studied with scintimammography using planar prone imaging (with a chest positioning device with semicircular lateral aperture on the imaging table) performed 15 min postinjection of 25-30 mCi 99mTc-sestamibi. Three planar views, right and left lateral prone and anterior supine thoracic views, were obtained (8-10 min/view). The entire breast and ipsilateral axillary region were included in the field of view. Excisional breast biopsy and/or fine needle aspiration cytology were performed in all patients within 4 wk after scintimammography. Axillary node dissection was also performed. The largest primary tumor measured 2 x 3 cm. There were ...

Research paper thumbnail of Normal glomerular filtration rate in long-term follow-up of children after orthotopic liver transplantation

Transplantation, Jan 15, 2006

Cyclosporine A (CyA) and tacrolimus are the principal immunosuppressive agents used for OLT in ch... more 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. We reviewed all OLT patients surviving >1 year at Sainte Justine Hospital from 1987 to 2003. The GFR (ml/min/1.73 m) was measured yearly by the Tc-99m DTPA single injection technique 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...

Research paper thumbnail of Evaluation de la perfusion pulmonaire differentielle: comparaison entre l’IRM et la scintigraphie

Research paper thumbnail of Radionuclide Captopril Renography in Postpartum Renal Artery Aneurysms

We report the case of a young woman with three left renal artery aneurysms, diagnosed immediately... more We report the case of a young woman with three left renal artery aneurysms, diagnosed immediately postpartum, associated with a de novo high blood pressure. To assess anatomical and functional characteristics of renal artery aneurysms, renal angiogram, MRI, intravenous pyelography, ultrasonography and radionuclide renography were performed. Two patent saccular renal artery aneurysms were demonstrated in the left kidney by renal angiogram. A larger, thrombosed aneurysm was also depicted on the left side on ultrasonography, MRI and renal angiogram. The larger aneurysm was responsible for renovascular disease of the middle third of the kidney, as demonstrated by captopril and baseline radionuclide renographic studies. It also impeded drainage of the lower pyelocalyceal group, without obstructing it, as shown by concomitant furosemide (Lasix) evaluations.

Research paper thumbnail of Incidence of gallium-67 citrate uptake in brown adipose tissue in neonates

Imaging in Medicine, 2013

Research paper thumbnail of Role of Scintigraphy in Musculoskeletal and Spinal Infections

Radiologic Clinics of North America, 2001

Research paper thumbnail of Imaging of Renovascular Hypertension: Respective Values of Renal Scintigraphy, Renal Doppler US, and MR Angiography1

RadioGraphics, 2000

Renovascular hypertension affects 15%-30% of patients who have clinical criteria suggestive of re... more 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.

Research paper thumbnail of Right Ventricle Myocardial Perfusion Scintigraphy: Feasibility and Expected Values in Children

Pediatric Cardiology, 2012

Stress myocardial perfusion scintigraphy imaging (SMPSI) has important applications for evaluatin... more 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.

Research paper thumbnail of Differential Pulmonary Perfusion Scan After Percutaneous Occlusion of the Patent Ductus Arteriosus: One-Decade Consecutive Longitudinal Study from a Single Institution

Pediatric Cardiology, 2008

Reduced left lung perfusion has been described following percutaneous occlusion of the patent duc... more 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 \40% was considered abnormal. LPS-1 was obtained in 95.8% and was abnormal in 31%. LPS-2, available in 48.2%, returned to normal in 65.7% (p \ 0.001). LPS-3, required in 6.2%, was normal in 55.6% (p = 0.07). Identifiable risk factors were low age and height (p \ 0.01), higher Q p /Q s ratio (p \ 0.05), and larger PDA size indexed for height (p \ 0.001) or body surface area (p \ 0.01). The number of coils or loops deployed in the pulmonary end of the PDA did not influence lung perfusion. In conclusion, we describe a high incidence of left lung perfusion reduction following percutaneous PDA occlusion, more likely in the young with large PDA. However, spontaneous recovery usually occurs within a few months.

Research paper thumbnail of Cumulative doses of adjunct 131I treatment depend on location of residual thyroid tissue after total thyroidectomy in differentiated thyroid cancer

Journal of Pediatric Surgery, 2007

Purpose: The aim of this study was to review the outcome after adjunct postoperative 131 I therap... more Purpose: The aim of this study was to review the outcome after adjunct postoperative 131 I therapy in patients with differentiated thyroid carcinoma (DTC) treated with total thyroidectomy (excluding medullary thyroid carcinoma). Methods: Retrospective chart review: Management protocol is total thyroidectomy with cervical node sampling, 131 I whole-body scan 3 weeks postoperatively to document residual thyroid tissue or metastasic lesions. Adjunct treatment consists of one or more 131 I (100-200 mci/1.73 m 2 ). Patients are considered disease free if 2 consecutive 131 I whole-body scan are negative with undetectable thyroglobulin level. Results: Twenty-one patients, 14 females and 7 males, with a mean age of 13.6 years were treated. Whole-body scan postoperatively revealed uptake in the thyroid bed (TB) in 10 patients, in cervical lymph nodes (CLN) in 9 patients, and in CLN and lungs in 2 patients. Patients with residual uptake in TB received a significantly lesser dose of 131 I (mean, 122 F 53 mci) than those with metastasic CLN (357 F 182 mci) ( P b .004) (t test) or lung mets (523.5 mci). With a mean follow-up of 7.8 years (range, 1-16 years), overall survival is 100% but disease-free survival is 100%, 66%, and 0% respectively for patients with residual disease in TB, CLN, and lungs. Conclusion: Patient with residual thyroid tissue in the TB required a significantly lesser number of treatments and doses of 131 I compared to patients with cervical node metastases with a 100% diseasefree survival. The best management of immediate postoperative residual cervical nodes (surgical excision vs 131 I) remains to be defined. The efficacy of 131 I therapy in patients with lung metastases remains controversial with complete remission unlikely. D

Research paper thumbnail of O0053 Normal Glomerular Filtration Rate (GFR) in Long-Term Follow-Up of Children After Orthotopic Liver Transplantation (Olt)

Journal of Pediatric Gastroenterology and Nutrition, 2004

Research paper thumbnail of Thallium-201 imaging with pharmacologic vasodilation: Comparison between dipyridamole and adenosine in detection of coronary artery disease

Journal of Nuclear Cardiology, 1995

Research paper thumbnail of Infected pacemaker causing septic lung emboli detected on FDG PET/CT

Journal of Nuclear Cardiology, 2010

Case report. An 8-year old girl was admitted to the hospital after presenting to the emergency ro... more Case report. An 8-year old girl was admitted to the hospital after presenting to the emergency room with fever. Blood cultures came back positive for Staphylococcus aureus. The patient had an endovascular pacemaker insertion for congenital atrioventricular (AV) block after progressing to complete heart block almost one year prior to hospitalization with fever. History, physical, laboratory examination, abdominal ultrasound, and a transthoracic echocardiogram did not identify an infectious source. The patient underwent an 18F-fluorodeoxyglucose (FDG) positron emission tomographycomputed tomography (PET-CT) scan for the evaluation of fever of unknown origin. The PET scan was done 71 min post-administration of 5.44 mCi (201.28 MBq) of F-18 FDG after fasting.

Research paper thumbnail of Comparison between dipyridamole and adenosine as pharmacologic coronary vasodilators in detection of coronary artery disease with thallium 201 imaging

Journal of Nuclear Cardiology, 1996

Both dipyridamole and adenosine are widely used as pharmacologic stressors with 201Tl imaging for... more 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 (p < 0.001), and the change in heart rate was 18 +/- 10 beats/min for adenosine and 8 +/- 7 beats/min for dipyridamole (p < 0.001). With regions of interest, ischemic/normal wall ratios were determined: 0.78 +/- 0.06 for adenosine and 0.83 +/- 0.08 for dipyridamole (p < 0.001). 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; p < 0.04) 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.

Research paper thumbnail of A High Prevalence of Dual Thyroid Ectopy in Congenital Hypothyroidism: Evidence for Insufficient Signaling Gradients during Embryonic Thyroid Migration or for the Polyclonal Nature of the Thyroid Gland?

The Journal of Clinical Endocrinology & Metabolism, 2012

Background: Thyroid ectopy results from the failure of the thyroid precursor cells to migrate fro... more Background: Thyroid ectopy results from the failure of the thyroid precursor cells to migrate from the primordial pharynx to the anterior part of the neck. Most ectopic thyroids are revealed by congenital hypothyroidism and present as a single round mass at the base of the tongue, with no other thyroid tissue. However, some cases have dual ectopy, with part of the tissue having partially migrated. We hypothesized that this occurs more frequently than previously reported.

Research paper thumbnail of Assessment of Differential Pulmonary Blood Flow Using Perfusion Magnetic Resonance Imaging

Investigative Radiology, 2006

We sought to assess the agreement between lung perfusion ratios calculated from pulmonary perfusi... more We sought to assess the agreement between lung perfusion ratios calculated from pulmonary perfusion magnetic resonance imaging (MRI) and those calculated from radionuclide (RN) perfusion scintigraphy. A retrospective analysis of MR and RN perfusion scans was conducted in 23 patients (mean age, 60 +/- 14 years) with different lung diseases (lung cancer = 15, chronic obstructive pulmonary disease = 4, cystic fibrosis = 2, and mesothelioma = 2). Pulmonary perfusion was assessed by a time-resolved contrast-enhanced 3D gradient-echo pulse sequence using parallel imaging and view sharing (TR = 1.9 milliseconds; TE = 0.8 milliseconds; parallel imaging acceleration factor = 2; partition thickness = 4 mm; matrix = 256 x 96; in-plane spatial resolution = 1.87 x 3.75 mm; scan time for each 3D dataset = 1.5 seconds), using gadolinium-based contrast agents (injection flow rate = 5 mL/s, dose = 0.1 mmol/kg of body weight). The peak concentration (PC) of the contrast agent bolus, the pulmonary blood flow (PBF), and blood volume (PBV) were computed from the signal-time curves of the lung. Left-to-right ratios of pulmonary perfusion were calculated from the MR parameters and RN counts. The agreement between these ratios was assessed for side prevalence (sign test) and quantitatively (Deming-regression). MR and RN ratios agreed on side prevalence in 21 patients (91%) with PC, in 20 (87%) with PBF, and in 17 (74%) with PBV. The MR estimations of left-to-right perfusion ratios correlated significantly with those of RN perfusion scans (P < 0.01). The correlation was higher using PC (r = 0.67) and PBF (r = 0.66) than using PBV (r = 0.50). The MR ratios computed from PBF showed the highest accuracy, followed by those from PC and PBV. Independently from the MR parameter used, in some patients the quantitative difference between the MR and RN ratios was not negligible. Pulmonary perfusion MRI can be used to assess the differential blood flow of the lung. Further studies in a larger group of patients are required to fully confirm the clinical suitability of this imaging method.

Research paper thumbnail of Comparison of Early and Delayed Scintigraphy with 99mTcApcitideand Correlationwith Contrast-EnhancedVenographyin Detection of Acute Deep Vein Thrombosis

Research paper thumbnail of Imaging of renovascular hypertension: Respective values of renal scintigraphy, renal Doppler US, and MR angiography

Radiographics

Renovascular hypertension affects 15%-30% of patients who have clinical criteria suggestive of re... more 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.

Research paper thumbnail of Metastatic axillary lymph node technetium-99m-MIBI imaging in primary breast cancer

Journal of Nuclear Medicine

Technetium-99m-MIBI scintimammography has been shown to be useful in the detection of primary bre... more Technetium-99m-MIBI scintimammography has been shown to be useful in the detection of primary breast cancer. The purpose of this study was to evaluate the potential role of scintimammography in detecting axillary lymph node involvement in patients undergoing scintimammography to detect primary breast cancer. A group of 100 women with breast cancer who were scheduled for a Level I-II axillary dissection were prospectively studied. Scintimammography was performed in all patients before histopathologic confirmation of breast cancer. Two lateral (prone imaging) views and one anterior (supine) planar thoracic view were obtained 10-15 min after the injection of 25-30 mCi 99mTc-MIBI (10 min/view) by using a special breast positioning device (foam cushion) placed over the imaging table. Both of the axilla were included in the field-of-view. Two experienced blinded observers reviewed all cases both from films and from the computer screen with contrast adjustment when needed. The site of intr...

Research paper thumbnail of Detection of renal artery stenosis: prospective comparison of captopril-enhanced Doppler sonography, captopril-enhanced scintigraphy, and MR angiography

AJR. American journal of roentgenology, 2001

The objective of our study was to compare the value of captopril-enhanced Doppler sonography, cap... more 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 th...

Research paper thumbnail of Technetium-99m-sestamibi prone scintimammography to detect primary breast cancer and axillary lymph node involvement

Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1995

The purpose of this study was to evaluate prospectively the sensitivity and specificity of scinti... more The purpose of this study was to evaluate prospectively the sensitivity and specificity of scintimammography in the detection of both primary breast cancer and axillary lymph node involvement. Sixty-five consecutive women referred for a suspicious breast lesion on clinical examination and/or with abnormal mammographies suggestive of malignancies were studied with scintimammography using planar prone imaging (with a chest positioning device with semicircular lateral aperture on the imaging table) performed 15 min postinjection of 25-30 mCi 99mTc-sestamibi. Three planar views, right and left lateral prone and anterior supine thoracic views, were obtained (8-10 min/view). The entire breast and ipsilateral axillary region were included in the field of view. Excisional breast biopsy and/or fine needle aspiration cytology were performed in all patients within 4 wk after scintimammography. Axillary node dissection was also performed. The largest primary tumor measured 2 x 3 cm. There were ...

Research paper thumbnail of Normal glomerular filtration rate in long-term follow-up of children after orthotopic liver transplantation

Transplantation, Jan 15, 2006

Cyclosporine A (CyA) and tacrolimus are the principal immunosuppressive agents used for OLT in ch... more 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. We reviewed all OLT patients surviving >1 year at Sainte Justine Hospital from 1987 to 2003. The GFR (ml/min/1.73 m) was measured yearly by the Tc-99m DTPA single injection technique 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...

Research paper thumbnail of Evaluation de la perfusion pulmonaire differentielle: comparaison entre l’IRM et la scintigraphie

Research paper thumbnail of Radionuclide Captopril Renography in Postpartum Renal Artery Aneurysms

We report the case of a young woman with three left renal artery aneurysms, diagnosed immediately... more We report the case of a young woman with three left renal artery aneurysms, diagnosed immediately postpartum, associated with a de novo high blood pressure. To assess anatomical and functional characteristics of renal artery aneurysms, renal angiogram, MRI, intravenous pyelography, ultrasonography and radionuclide renography were performed. Two patent saccular renal artery aneurysms were demonstrated in the left kidney by renal angiogram. A larger, thrombosed aneurysm was also depicted on the left side on ultrasonography, MRI and renal angiogram. The larger aneurysm was responsible for renovascular disease of the middle third of the kidney, as demonstrated by captopril and baseline radionuclide renographic studies. It also impeded drainage of the lower pyelocalyceal group, without obstructing it, as shown by concomitant furosemide (Lasix) evaluations.

Research paper thumbnail of Incidence of gallium-67 citrate uptake in brown adipose tissue in neonates

Imaging in Medicine, 2013

Research paper thumbnail of Role of Scintigraphy in Musculoskeletal and Spinal Infections

Radiologic Clinics of North America, 2001

Research paper thumbnail of Imaging of Renovascular Hypertension: Respective Values of Renal Scintigraphy, Renal Doppler US, and MR Angiography1

RadioGraphics, 2000

Renovascular hypertension affects 15%-30% of patients who have clinical criteria suggestive of re... more 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.

Research paper thumbnail of Right Ventricle Myocardial Perfusion Scintigraphy: Feasibility and Expected Values in Children

Pediatric Cardiology, 2012

Stress myocardial perfusion scintigraphy imaging (SMPSI) has important applications for evaluatin... more 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.

Research paper thumbnail of Differential Pulmonary Perfusion Scan After Percutaneous Occlusion of the Patent Ductus Arteriosus: One-Decade Consecutive Longitudinal Study from a Single Institution

Pediatric Cardiology, 2008

Reduced left lung perfusion has been described following percutaneous occlusion of the patent duc... more 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 \40% was considered abnormal. LPS-1 was obtained in 95.8% and was abnormal in 31%. LPS-2, available in 48.2%, returned to normal in 65.7% (p \ 0.001). LPS-3, required in 6.2%, was normal in 55.6% (p = 0.07). Identifiable risk factors were low age and height (p \ 0.01), higher Q p /Q s ratio (p \ 0.05), and larger PDA size indexed for height (p \ 0.001) or body surface area (p \ 0.01). The number of coils or loops deployed in the pulmonary end of the PDA did not influence lung perfusion. In conclusion, we describe a high incidence of left lung perfusion reduction following percutaneous PDA occlusion, more likely in the young with large PDA. However, spontaneous recovery usually occurs within a few months.

Research paper thumbnail of Cumulative doses of adjunct 131I treatment depend on location of residual thyroid tissue after total thyroidectomy in differentiated thyroid cancer

Journal of Pediatric Surgery, 2007

Purpose: The aim of this study was to review the outcome after adjunct postoperative 131 I therap... more Purpose: The aim of this study was to review the outcome after adjunct postoperative 131 I therapy in patients with differentiated thyroid carcinoma (DTC) treated with total thyroidectomy (excluding medullary thyroid carcinoma). Methods: Retrospective chart review: Management protocol is total thyroidectomy with cervical node sampling, 131 I whole-body scan 3 weeks postoperatively to document residual thyroid tissue or metastasic lesions. Adjunct treatment consists of one or more 131 I (100-200 mci/1.73 m 2 ). Patients are considered disease free if 2 consecutive 131 I whole-body scan are negative with undetectable thyroglobulin level. Results: Twenty-one patients, 14 females and 7 males, with a mean age of 13.6 years were treated. Whole-body scan postoperatively revealed uptake in the thyroid bed (TB) in 10 patients, in cervical lymph nodes (CLN) in 9 patients, and in CLN and lungs in 2 patients. Patients with residual uptake in TB received a significantly lesser dose of 131 I (mean, 122 F 53 mci) than those with metastasic CLN (357 F 182 mci) ( P b .004) (t test) or lung mets (523.5 mci). With a mean follow-up of 7.8 years (range, 1-16 years), overall survival is 100% but disease-free survival is 100%, 66%, and 0% respectively for patients with residual disease in TB, CLN, and lungs. Conclusion: Patient with residual thyroid tissue in the TB required a significantly lesser number of treatments and doses of 131 I compared to patients with cervical node metastases with a 100% diseasefree survival. The best management of immediate postoperative residual cervical nodes (surgical excision vs 131 I) remains to be defined. The efficacy of 131 I therapy in patients with lung metastases remains controversial with complete remission unlikely. D

Research paper thumbnail of O0053 Normal Glomerular Filtration Rate (GFR) in Long-Term Follow-Up of Children After Orthotopic Liver Transplantation (Olt)

Journal of Pediatric Gastroenterology and Nutrition, 2004

Research paper thumbnail of Thallium-201 imaging with pharmacologic vasodilation: Comparison between dipyridamole and adenosine in detection of coronary artery disease

Journal of Nuclear Cardiology, 1995

Research paper thumbnail of Infected pacemaker causing septic lung emboli detected on FDG PET/CT

Journal of Nuclear Cardiology, 2010

Case report. An 8-year old girl was admitted to the hospital after presenting to the emergency ro... more Case report. An 8-year old girl was admitted to the hospital after presenting to the emergency room with fever. Blood cultures came back positive for Staphylococcus aureus. The patient had an endovascular pacemaker insertion for congenital atrioventricular (AV) block after progressing to complete heart block almost one year prior to hospitalization with fever. History, physical, laboratory examination, abdominal ultrasound, and a transthoracic echocardiogram did not identify an infectious source. The patient underwent an 18F-fluorodeoxyglucose (FDG) positron emission tomographycomputed tomography (PET-CT) scan for the evaluation of fever of unknown origin. The PET scan was done 71 min post-administration of 5.44 mCi (201.28 MBq) of F-18 FDG after fasting.

Research paper thumbnail of Comparison between dipyridamole and adenosine as pharmacologic coronary vasodilators in detection of coronary artery disease with thallium 201 imaging

Journal of Nuclear Cardiology, 1996

Both dipyridamole and adenosine are widely used as pharmacologic stressors with 201Tl imaging for... more 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 (p < 0.001), and the change in heart rate was 18 +/- 10 beats/min for adenosine and 8 +/- 7 beats/min for dipyridamole (p < 0.001). With regions of interest, ischemic/normal wall ratios were determined: 0.78 +/- 0.06 for adenosine and 0.83 +/- 0.08 for dipyridamole (p < 0.001). 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; p < 0.04) 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.

Research paper thumbnail of A High Prevalence of Dual Thyroid Ectopy in Congenital Hypothyroidism: Evidence for Insufficient Signaling Gradients during Embryonic Thyroid Migration or for the Polyclonal Nature of the Thyroid Gland?

The Journal of Clinical Endocrinology & Metabolism, 2012

Background: Thyroid ectopy results from the failure of the thyroid precursor cells to migrate fro... more Background: Thyroid ectopy results from the failure of the thyroid precursor cells to migrate from the primordial pharynx to the anterior part of the neck. Most ectopic thyroids are revealed by congenital hypothyroidism and present as a single round mass at the base of the tongue, with no other thyroid tissue. However, some cases have dual ectopy, with part of the tissue having partially migrated. We hypothesized that this occurs more frequently than previously reported.

Research paper thumbnail of Assessment of Differential Pulmonary Blood Flow Using Perfusion Magnetic Resonance Imaging

Investigative Radiology, 2006

We sought to assess the agreement between lung perfusion ratios calculated from pulmonary perfusi... more We sought to assess the agreement between lung perfusion ratios calculated from pulmonary perfusion magnetic resonance imaging (MRI) and those calculated from radionuclide (RN) perfusion scintigraphy. A retrospective analysis of MR and RN perfusion scans was conducted in 23 patients (mean age, 60 +/- 14 years) with different lung diseases (lung cancer = 15, chronic obstructive pulmonary disease = 4, cystic fibrosis = 2, and mesothelioma = 2). Pulmonary perfusion was assessed by a time-resolved contrast-enhanced 3D gradient-echo pulse sequence using parallel imaging and view sharing (TR = 1.9 milliseconds; TE = 0.8 milliseconds; parallel imaging acceleration factor = 2; partition thickness = 4 mm; matrix = 256 x 96; in-plane spatial resolution = 1.87 x 3.75 mm; scan time for each 3D dataset = 1.5 seconds), using gadolinium-based contrast agents (injection flow rate = 5 mL/s, dose = 0.1 mmol/kg of body weight). The peak concentration (PC) of the contrast agent bolus, the pulmonary blood flow (PBF), and blood volume (PBV) were computed from the signal-time curves of the lung. Left-to-right ratios of pulmonary perfusion were calculated from the MR parameters and RN counts. The agreement between these ratios was assessed for side prevalence (sign test) and quantitatively (Deming-regression). MR and RN ratios agreed on side prevalence in 21 patients (91%) with PC, in 20 (87%) with PBF, and in 17 (74%) with PBV. The MR estimations of left-to-right perfusion ratios correlated significantly with those of RN perfusion scans (P < 0.01). The correlation was higher using PC (r = 0.67) and PBF (r = 0.66) than using PBV (r = 0.50). The MR ratios computed from PBF showed the highest accuracy, followed by those from PC and PBV. Independently from the MR parameter used, in some patients the quantitative difference between the MR and RN ratios was not negligible. Pulmonary perfusion MRI can be used to assess the differential blood flow of the lung. Further studies in a larger group of patients are required to fully confirm the clinical suitability of this imaging method.