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Biomedical subjects

S T Treves

Publications and source records attributed to S T Treves.

At least 55 records · Page 3Linked to original sources
PubMed1996

Isolated peripheral pulmonary artery stenoses in the adult.

BACKGROUND: Isolated peripheral pulmonary artery stenosis (PPS) in the adult is rare and frequently unsuspected. We review in this article our experience with 12 adult patients with isolated PPS, half of whom had been previously diagnosed with chronic pulmonary thromboembolic disease. METHODS AND RESULTS: The presentation, evolution, and management of 12 adults with isolated PPS, 17 to 51 years of age (mean, 36.2 +/- 9.7 years), were evaluated. Presenting symptoms were dyspnea and fatigue. Three patients had New York Heart Association (NYHA) functional class III or greater. Lung perfusion scans revealed multiple segmental abnormalities in flow distribution in all patients. Oxygen desaturation at rest was present in 4 patients. At catheterization, right ventricular (RV) pressure was suprasystemic in 2 patients, systemic in 1, and more than half-systemic in 7. All had multiple bilateral non-uniform stenoses in segmental and subsegmental arteries. Balloon pulmonary angioplasty (BPA) to decrease RV hypertension and improve pulmonary flow distribution was performed in 11 patients. After BPA, vessel diameter increased > 50% in 10 patients, distal pulmonary artery pressure increased > or = 30% in 6, and RV pressure decreased > 30% in 5. One patient died shortly after BPA as a result of pulmonary hemorrhage. Immediate procedural success was achieved in 9 of 11 patients. At a mean follow-up period of 52 +/- 32 months, 7 patients had sustained symptomatic improvement (NYHA class I-II). CONCLUSIONS: We describe a severe syndrome of isolated PPS in the adult that mimics chronic pulmonary thromboembolic disease. Pulmonary hemodynamics and angiography are required for definitive diagnosis. BPA may offer these patients successful short-term reduction in RV hypertension and alleviation of symptomatology.

Adolescent↗
PubMed1996

Thallium-201 uptake in Langerhans cell histiocytosis of bone.

A case in which there was thallium-201 (201Tl) uptake in Langerhans cell histiocytosis (LCH) of the left femoral diaphysis is presented. The authors propose that 201Tl scintigraphy is potentially useful in the diagnosis and follow-up of patients with LCH.

Bone Diseases↗
PubMed1996

Osteoid osteoma: comparative utility of high-resolution planar and pinhole magnification scintigraphy.

A characteristic scintigraphic pattern of focally intense skeletal tracer uptake surrounded by less prominently increased uptake has been described for osteoid osteomas. Demonstration of this finding is useful in the evaluation of patients with suspected osteomas. Pinhole magnification scintigraphy was significantly more effective than high-resolution planar scintigraphy at revealing this pattern in 19 osteoid osteomas of the appendicular skeleton. A similar advantage was not observed for vertebral osteoid osteomas. The absence of the characteristic pattern aided in differentiating other pathology from osteoid osteomas in seven patients. The authors recommend that skeletal scintigraphy of patients with suspected osteoid osteomas include pinhole magnification imaging.

Adolescent↗
PubMed1996

Localization of Tc-99m MDP in neuroblastoma metastases to the liver and lung.

Localization of skeletal tracer in a neuroblastoma primary is common but localization in extraskeletal metastatic sites has not received recognition. Tc-99m MDP concentration in hepatic or pulmonary metastases was noted in three of ten patients with such metastases. Lesion size appears to be important for demonstrating these metastases with Tc-99m MDP. This was particularly true for hepatic metastases, which were identified only when they were 5 cm or greater in diameter.

Bone and Bones↗
PubMed1996

Functional bladder capacity measured during radionuclide cystography in children.

PURPOSE: To estimate functional bladder capacity (FBC) during direct radionuclide cystography and to assess the relationship between vesicoureteral reflux and FBC. MATERIALS AND METHODS: By using 5,165 direct radionuclide cystograms in patients aged newborn to 14 years, linear and nonlinear models were fit to estimate FBC from age. Analysis was performed on girls and boys separately. In a subgroup, height and weight were evaluated as predictors of FBC. Linear models were used to assess differences in predicted FBC according to sex and reflux status. RESULTS: The relationship between FBC and age is best described by a nonlinear power function. Percentiles derived from this model are close to the empiric percentiles of FBC. When controlling for age, girls and patients with reflux had larger bladder capacities (P < .01). Height and weight did not improve FBC prediction accuracy. CONCLUSION: FBC follows a curve with increasing age. The nonlinear relationship between FBC and age appears to be consistent with maturation in infants and children.

Adolescent↗
PubMed1996

Registration and alignment of three-dimensional images: an interactive visual approach.

A three-dimensional registration and alignment algorithm was developed to align single photon emission computed tomography examinations and magnetic resonance images. Operators manipulated images interactively with real-time visual feedback, with use of both internal and surface features to achieve accurate alignment. Operators aligned five brain phantom examinations (accuracy, 1.6 pixels; consistency, 0.7 pixels) and eight patient brain examinations (consistency, 0.5 pixels).

Algorithms↗
PubMed1996

Technetium-99m-HMPAO SPECT in Sturge-Weber syndrome.

UNLABELLED: Technetium-99m-HMPAO interictal SPECT was performed on three pediatric patients with Sturge-Weber syndrome (SWS). RESULTS: Brain SPECT of all three patients demonstrated markedly diminished tracer localization in the affected hemisphere. In one patient, the SPECT abnormality was more extensive than the associated abnormalities on CT and MRI. CONCLUSION: Technetium-99m-HMPAO brain SPECT can detect cerebral perfusion abnormalities associated with SWS and deserves consideration in the imaging evaluation of SWS patients.

Brain↗
PubMed1996

Natural history of vesicoureteral reflux in siblings.

PURPOSE: We attempted to assess the natural course of vesicoureteral reflux after it was detected in asymptomatic siblings of children with reflux, and to determine predictors of and time to resolution. MATERIALS AND METHODS: We reviewed the records and radionuclide cystograms of 76 girls and 32 boys 2 weeks to 103 months old (mean age 21 months) with vesicoureteral reflux detected in a sibling screening program. Predictors were determined using logistic regression and survival analysis. RESULTS: Vesicoureteral reflux resolved in 52.8% of cases at a mean followup of 18.5 months. Yearly resolution rates exceeded 28%. Predictors of the likelihood of resolution were not identified. At diagnosis unilateral reflux and mild reflux were independent and univariate predictors, respectively, of more rapid resolution. CONCLUSIONS: By showing that spontaneous resolution is likely for children with vesicoureteral reflux detected in a sibling screening program, this study supports nonsurgical management with annual imaging evaluation.

Child↗
PubMed1996

Ictal and interictal technetium-99m-bicisate brain SPECT in children with refractory epilepsy.

UNLABELLED: Identification of epileptogenic foci in patients with refractory epilepsy remains a significant diagnostic challenge. Magnetic resonance imaging studies frequently fail to reveal an anatomic origin for the seizures, and scalp electroencephalography is often limited to identification of the involved hemisphere. Functional imaging modalities such as PET and SPECT are more promising tools for this application because they reflect the functional pathology associated with the seizure. These changes are more pronounced ictally, but until recently, no radiopharmaceutical was available that could be used routinely for ictal SPECT. The present study was therefore undertaken to determine whether 99mTc-bicisate could be used in ictal SPECT in pediatric patients with refractory epilepsy, to compare the patterns of ictal and interictal blood flow in these patients and to compare the localization information provided by ictal SPECT with that available from other techniques. METHODS: Technetium-99m-bicisate/SPECT was compared prospectively with scalp EEG for its ability to identify a possible seizure focus in pediatric patients with refractory epilepsy. Ictal and interictal SPECT studies were performed in 10 patients (3-19 yr old, mean age 10.9 +/- 4.3 yr; 7 female, 3 male) in whom MRI scans revealed no lesions that might be responsible for the seizures. RESULTS: Ictal SPECT was performed in all patients, and all ictal studies revealed focal perfusion abnormalities. By comparison, four of the interictal SPECT studies showed regional hypoperfusion that corresponded to the regions of hyperperfusion in the ictal studies, and three showed regional hyperperfusion corresponding to the hyperperfused regions in the ictal studies. Three interictal studies revealed no abnormal perfusion. Scalp EEG provided localization information in five patients. CONCLUSION: These initial results suggest that ictal SPECT with 99mTc-bicisate is a more promising tool for the identification of epileptogenic foci than interictal SPECT or scalp EEG in patients without focal abnormalities on MRI.

Brain↗
PubMed1996

Radionuclide cystography: a review of its use in adults.

OBJECTIVE: Although a common procedure in pediatric nuclear medicine, direct radionuclide cystography is infrequently performed in adults in whom there are few reports on its use. We describe the use of direct radionuclide cystography in adults. EXPERIMENTAL DESIGN: The medical records and direct radionuclide cystograms of 56 adults who underwent 75 studies at this institution over a 5 year period were reviewed. SETTING: The study was performed at a major university teaching hospital. PATIENTS: The major indications were for assessment of recurrent urinary tract infection and follow-up of known vesicoureteric reflux. RESULTS: Overall, reflux was demonstrated in 36% patients. It was most frequently mild or moderate in severity and detected during both the filling and voiding phases of the study. Patients with neurogenic bladder dysfunction had a higher incidence of vesicoureteric reflux and significantly smaller functional bladder capacity than other referred patients. All studies were well tolerated, easily performed and without complication. CONCLUSIONS: Given the lower radiation exposure and higher sensitivity than voiding cystourethrography, we believe that radionuclide cystography can be recommended in the evaluation of vesicoureteric reflux in adults as well as children. In the group of adults whose genitourinary anatomy is already known from other investigations, radionuclide cystography may be particularly suited.

Adolescent↗
PubMed1995

Renal dysplasia in infants: appearance on 99mTc DMSA scintigraphy.

Infantile renal dysplasias, including multicystic dysplastic kidneys (MCDK), are reported rarely to accumulate radiopharmaceuticals on renal scintigraphy. 99mTc DMSA is a highly sensitive tracer for detecting functioning renal cortical tissue and may be more suited to studying renal dysplasia than 99mTc DTPA. We reviewed the ultrasound studies and 99mTc DMSA scintigrams of 42 infants (age range 1-12 months) with known or suspected MCDK. Overall, uptake on 99mTc DMSA scintigraphy was evident in 6/41 (15%) dysplastic kidneys. Of the 18 patients who underwent nephrectomy, histopathological examination revealed that uptake correlated closely with the presence of mature renal cortical tissue in the affected kidney. Our study shows that a small, but significant number of MCDK will show low-grade uptake on DMSA scintigraphy. This finding may be relevant given the reliance placed on renal scintigraphy in planning treatment for infants with suspected MCDK, particularly with the increasing trend for the non-operative management of this condition.

Female↗
PubMed1995

An improved 191Os/191mIr generator using a hybrid anion exchanger.

Iridium-191m is an attractive radionuclide for first-pass radionuclide angiography, but development of an 191Os/191mIr generator with high 191mIr yield has proven difficult. The use of trans-dioxobisoxalatoosmate(VI) as a parent species results in a higher initial yield (20 to 25%/mL), but the yield decreases over time. Using an anion-exchange column of tridodecylmethylammonium chloride-treated silica gel and AG MP-1 resin, we have developed an improved 191Os/191mIr generator with higher initial yield (25 to 30%/mL) and a slower rate of decrease than the previous design.

Ion Exchange Resins↗