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F X Sundram

Publications and source records attributed to F X Sundram.

At least 19 recordsLinked to original sources

188rhenium-TDD-lipiodol in treatment of inoperable primary hepatocellular carcinoma--a case report.

INTRODUCTION: The aim of this study was to investigate the potential of using 188Re Lipiodol for selective internal radiation therapy of inoperable hepatocellular carcinoma (HCC). CLINICAL PICTURE: A 33-year-old female with poorly-differentiated multicentric HCC, elevated alpha-fetoprotein (AFP) and increased serum alkaline phosphatase. TREATMENT: Over a 2-month interval, the patient was treated twice with 4GBq of 188Re-TDD-Lipiodol. OUTCOMES: There was good localisation of 188Re Lipiodol in the tumours, but also in thyroid (first treatment) and gastrointestinal tract (both treatments). So far (5 months post-treatment), the patient remains well with stable disease. CONCLUSIONS: 188Re Lipiodol can be an effective radiopharmaceutical for the treatment of HCC; however, more work must be done to minimise the uptake in bowel.

Adult↗

Two cases of medullary thyroid carcinoma.

INTRODUCTION: Medullary thyroid carcinoma (MTC) is a rare thyroid malignancy but accounts for a significant mortality. We present 2 cases of MTC and review the literature regarding its management and genetic screening. CLINICAL PICTURE: Patient 1 presented after a routine health screening and subsequently was found to have a germline mutation for MEN 2A. Patient 2 presented with sweating irritability and a thyroid mass which illustrates the progressive relentless nature of the disease and highlights current imaging practice. TREATMENT: Both patients underwent extensive surgery and received postoperatively ablative dose of radioactive iodine. Patient 2 also had a large dose I-131 MIBG therapy and further surgery. OUTCOME: In Patient 1, postoperative calcitonins remained elevated indicating residual disease. Patient 2 underwent further radioguided surgery; however, his postoperative calcitonins remained elevated. CONCLUSION: MTC can be relentless. Routine genetic screening of all patients with MTC, Tc-99m pentavalent (V) DMSA imaging, near total thyroidectomy with routine central neck dissections and removal of all lymph nodes in the central neck compartment should be performed.

Adult↗

Intermediate probability lung scans (IPLS): retrospective review of 82 cases.

OBJECTIVE: In the light of a reported 30-40% prevalence of pulmonary embolism (PE) in intermediate probability lung scans (IPLS) based on results of the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study, we examined the frequency of documented PE in 82 patients with IPLS, the management strategy employed in these patients with regards to additional imaging (e.g. further evaluation with venous sonography or spiral computed tomographic angiography (CTA)), anticoagulation therapy, and subsequent follow-up outcomes. METHOD: Retrospective review of the medical records of 82 patients with intermediate probability ventilation-perfusion (V/Q) lung scans from January 1998 to July 1999. RESULTS: 14.1% of V/Q scans were reported as having an intermediate probability of PE. 72% of IPLS were subject to further evaluation with venous Doppler ultrasound and/or CTA, and 39% of these patients had evidence of thrombo-embolic disease. All patients with imaging evidence of thromboembolic disease were started on anticoagulation therapy. In addition, 19 patients were treated based on clinical judgement. Amongst the 35 patients who were not treated, 17 (49%) were based on clinical findings without further imaging. There was no mortality on follow-up of 28 cases of untreated IPLS. CONCLUSION: The majority of IPLS will have further imaging, out of which over one-third will have thrombo-embolic disease. Approximately half of IPLS cases will receive anticoagulation therapy. No mortality or PE was found on follow-up of patients who were not treated.

Adolescent↗

A non-invasive isotope dilution technique for quantifying hepatic blood flow using radiolabelled red blood cells.

Clinically significant changes in hepatic haemodynamics accompany the development of portal hypertension, hepatocellular carcinoma, liver metastases and liver cirrhoses, and after major liver resection. Hepatic blood flow parameters, such as hepatic arterial flow (HAF), hepatic portal flow (HPF), total hepatic blood flow (THBF) and hepatic perfusion index (HPI), are useful adjuncts to the diagnosis of liver pathology, the evaluation of disease progress and prognostication. Here, we describe a non-invasive method that combines the measurement of these parameters in a single study in real time. Red blood cells from eight pigs were labelled with 99Tc(m) using an in-vitro method and re-injected into the pigs. Data acquisition over the heart, lungs, liver and kidneys was started immediately and a blood sample was obtained 15 min post-injection. Hepatic arterial flow was determined from the ratio of the maximum gradients between the integrated time-activity curve of the left ventricle and the first-pass time-activity curve of the liver before the peak of the kidneys time-activity curve. The hepatic perfusion index was determined by comparing the slope of the liver time-activity curve before and after the kidney peak. Hepatic portal flow was determined from the hepatic arterial flow and the hepatic perfusion index, and total hepatic blood flow was determined as the sum of arterial and portal flow. The results were compared against those obtained from a clearance method using 99Tc(m)-DISIDA. The average hepatic perfusion index was 0.38, and the average hepatic arterial flow and hepatic portal flow were 168.3 +/- 52.9 and 274.6 +/- 60.1 ml x min(-1) respectively. The average total hepatic blood flow was 442.8 +/- 53.5 ml x min(-1), while the total hepatic flow determined by 99Tc(m)-DISIDA clearance was 419.7 +/- 62.6 ml x min(-1). No significant difference in total hepatic blood flow was found between the two methods. The results of this study show that it is possible to obtain all hepatic haemodynamics data in a single study using a non-invasive method.

Animals↗

99mTc-sestamibi and 131I whole-body scintigraphy and initial serum thyroglobulin in the management of differentiated thyroid carcinoma.

UNLABELLED: 99mTc-sestamibi whole-body scanning has been used in the postoperative assessment of differentiated thyroid carcinoma together with 131I whole-body scanning and serum thyroglobulin (Tg) estimation. This study compared 99mTc-sestamibi whole-body scanning with 131I whole-body scanning in the context of initial serum Tg levels of patients after total or near-total thyroidectomy who were taken off thyroxine suppression therapy and who had no 131I ablation before surgery. METHODS: A prospective study of 360 patients was undertaken. 99mTc-sestamibi whole-body scintigraphy was performed at least 5 wk after thyroidectomy and was followed by 131I whole-body scanning. The patients had no thyroxine suppression for 5 wk, and Tg was measured thereafter. Radiologic studies (chest radiography, CT, MRI, sonography, and bone scanning) and histopathologic examinations were performed to clarify the presence of metastases with positive uptake on either 99mTc-sestamibi scans or 131I whole-body scans. Positive scans were defined as those with the presence of thyroid remnants, lymph node disease, or metastases. RESULTS: Two hundred fifty-nine (71.9%) of the 360 patients had initial serum Tg levels < 30 ng/mL (group 1), whereas 101 (28.1%) had initial serum Tg levels > or = 30 ng/mL (group 2). Of the 259 group 1 patients, 82 had positive 99mTc-sestamibi scans and 113 had positive 131I scans; 71.7% of patients with positive 1311 scans also had positive 99mTc-sestamibi scans, and 98.8% of patients with positive 99mTc-sestamibi scans also had positive 131I scans. Of the 101 group 2 patients, 81 had positive 99mTc-sestamibi scans and 97 had positive 131I scans; 83.5% of patients with positive 131I scans also had positive 99mTc-sestamibi scans, and all patients with positive 99mTc-sestamibi scans also had positive 131I scans. Of those with initial serum Tg levels > or = 30 ng/mL (group 2), 27.2% had thyroid remnants and 68.8% had lymph node disease or metastases. 131I scanning detects more thyroid remnants and lung metastases than does 99mTc-sestamibi scanning. CONCLUSION: Our findings suggest that, compared with 131I scanning, 99mTc-sestamibi scanning is less sensitive in detecting thyroid remnants and lung metastases but appears to be more useful in the detection of lymph node disease before initial 131I treatment.

Diagnostic Imaging↗

Technetium-99m sestamibi for the assessment of myocardial salvage following reperfusion therapy in acute myocardial infarction.

INTRODUCTION: Reperfusion therapy with either thrombolysis or angioplasty has been shown to be beneficial in acute myocardial infarction. Tc-99m sestamibi is a myocardial tracer that can be used to assess myocardial salvage because of its property of very limited redistribution. MATERIALS AND METHODS: To assess the feasibility of this technique locally, Tc-99m sestamibi was injected before and after reperfusion therapy with angioplasty (n = 11) or streptokinase (n = 18) in 29 patients with acute myocardial infarction (anterior = 25, inferior = 4). Single-photon emission computed tomography (SPECT) was performed within 4 hours of reperfusion and repeated 5 to 7 days later. RESULTS: Initial perfusion defect size ranged from 6% to 78% (mean 36.3 +/- 18.7%), and final defect size from 0% to 50% of the left ventricle (mean 23.7 +/- 14.8%, P < 0.001). Patients with proximal left anterior descending artery (LAD) lesions had larger defects compared to those with mid LAD lesions (mean defect size 52% for pLAD versus 28% for mLAD, P < 0.013). However, there were wide variations in initial defect size (myocardium at risk) for a given infarct-related artery location. The mean decrease in defect size was 12% in the 28 patients with patent arteries compared to only 2% in the patient with an occluded artery (47% to 45%). There was no significant difference in amount of salvage between patients who had thrombolysis (mean 13%, P = 0.0003) and patients who had percutaneous transluminal coronary angioplasty (PTCA) (mean 12%, P = 0.005). CONCLUSIONS: Assessment of myocardial salvage is feasible using Tc-99m sestamibi SPECT imaging. It allows for quantitation of myocardium at risk and the amount of myocardial salvage, which is not possible by angiography alone.

Adult↗

Evaluation of technetium-99m ciprofloxacin (Infecton) in the imaging of infection.

INTRODUCTION: The aim of this study was to evaluate the usefulness of technetium-99m (Tc-99m) ciprofloxacin in imaging inflammation/infection. The ciprofloxacin for labelling, as a kit, was obtained from St Bartholomew's Hospital in London. MATERIALS AND METHODS: Patients were injected intravenously with Tc-99m ciprofloxacin and imaging was done at 10 minutes, 4 hours and 24 hours if necessary. Tomographic images (SPECT) were obtained in a few patients. Ninety-six patients were studied using Tc-99m ciprofloxacin. Forty-eight patients had bone scans and 22 had Tc-99m IgG scans. Eight patients were imaged using Tc-99m HMPAO labelled white blood cell, and bacteriological culture results were available in 24 patients. Organisms cultured included Acinetobacter baumanii, Streptococcus, Staphylococcus aureus, Pseudomonas, Klebsiella, Blastococidia, Methicillin-resistant S. aureus, Salmonella and Candida. RESULTS: Findings were evaluated against microbiology, alternative imaging modalities and clinical outcome. There were 47 true positives, 33 true negatives, 5 false positives and 11 false negatives, giving a sensitivity of 81% and specificity of 87%. The positive and negative predictive values were 90% and 75%, respectively. There were no side effects and the scan was particularly useful in the evaluation of painful joint prosthesis to exclude infection. Repeat studies on 8 patients given antibiotics over a long period were very useful in deciding on termination of the antibiotic treatment.

Abscess↗

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Abstracting and Indexing↗

Bone mineral density--correlation between quantitative ultrasound characteristics and dual energy X-ray absorptiometry.

The speed of sound (SOS) and the broadband ultrasound attenuation (BUA), as determined by quantitative ultrasound at the calcaneum, were correlated with the bone mineral density (BMD) measurements using dual-energy X-ray absorptiometry at the femoral neck and the lumbar spine in 110 females. There were moderate correlations of 0.629, 0.623 and 0.594 between the BMD at the anterior-posterior lumbar spine, lateral lumbar spine and femoral neck with the SOS at the calcaneum (all P < 0.001). The corresponding correlations with BUA were 0.646, 0.643 and 0.628 respectively (all P < 0.001). This suggests that quantitative ultrasound may be reasonably accurate and useful for the assessment of osteoporosis.

Absorptiometry, Photon↗

Radioiodine (I-131) therapy and the incidence of hypothyroidism.

Radioiodine (I-131) is one of the accepted forms of treatment for thyrotoxicosis. The major drawback of this treatment is the definite incidence of hypothyroidism, which is either early or late, and is cumulative. We set out to analyse the local incidence of this outcome. Patients with hyperthyroidism, treated with radioiodine from 1984 to end of 1989, and still on follow-up with the Department of Nuclear Medicine, Singapore General Hospital were analysed for the incidence of hypothyroidism. Three hundred and eighty-two patients were analysed (305 females, 77 males). Their ages ranged from 14 to 85 years (mean 48.2, SD 11.1 years). The doses of radioiodine ranged from 4 to 18 mCi (mean 7.6 mCi, SD 1.8 mCi). Two hundred and sixty-two patients who received I-131 only required a single dose, while 87 needed one repeated dose of I-131, and 33 needed more than 2 doses. Of the 382 patients, 271(70.9%) became clinically hypothyroid, 6 (1.6%) were subclinically hypothyroid, 100 (26.7%) were euthyroid and 3 (0.8%) remained hyperthyroid. One hundred and eighty-one patients (47.4%) were clinically hypothyroid at the end of 1 year, and an average rise of 4.8% per year was observed from the second to the fifth year. From the sixth year onwards, the average incidence of hypothyroidism was 1% per year. I-131 is indeed an effective means of controlling thyrotoxicosis (99.2% were no longer hyperthyroid). The main problem with this treatment is hypothyroidism, and this is easily managed with L-thyroxine.

Adolescent↗

Radionuclide imaging in primary hyperparathyroidism using 99mTc sestamibi--four case reports.

Radionuclide imaging using the 99mTc sestamibi either singly or as a subtraction technique with pertechnetate is a recent and reliable method in localising parathyroid adenomas prior to surgery. This is of use in pre-operative planning, as well as in failed first neck exploration. Four local patients with primary hyperparathyroidism whose parathyroid adenomas were localised by this scintigraphy are presented. The value and limitations of this imaging modality are discussed.

Adult↗

Clinical studies of alveolar-capillary permeability using technetium-99m DTPA aerosol.

Soluble radioaerosols such as technetium-99m diethylene triamine pentacetate (DTPA) permit simple quantitative studies of alveolar-capillary permeability to be performed, since the submicronic aerosols are deposited mainly at the lung periphery and are cleared across the alveolar-capillary membrane. Regional alterations in permeability can also be noted using this radionuclide technique. We have measured the pulmonary epithelial permeability in normal subjects and the alteration in smokers, in glue-sniffers, in patients with inhalation burns, in chronic obstructive pulmonary disease (COPD) and in patients with lung metastases from thyroid cancer treated with radioiodine 131I. In the normal volunteers, the time taken for 50% of inhaled 99mTcDTPA to be cleared form the lungs (T1/2) was 66 minutes +/- 1sd of 12 mins. The smokers had a mean T1/2 of 20 mins +/- 1sd 4 min. In the hard-core glue-sniffing group, the majority were smokers who had stopped smoking and glue-sniffing for periods varying from 1 day to 42 days, and it was possible to note the changes in clearance times against period of abstinence. In the patients with inhalations burns, there was change in lung clearance arising from pulmonary epithelial damage; these patients showed increased rate of clearance (short T1/2) with mean T1/2 of 36 min +/- 1sd of 11 mins, while the retention images revealed regional lung damage in moderately severe inhalation burns. Twenty-four patients with COPD had inhalation scans done with Tc-99m tin colloid radioaerosol, and these images were compared with the perfusion lung scans done with 99mTc macroaggregated albumin (MAA); in general the perfusion images matched the defects noted in the inhalation scans. The 99mTc DTPA clearance rate in these patients was normal i.e. T 1/2 = 78 +/- 14 mins. In the thyroid cancer patients with lung metastases, who had high doses of radioiodine treatment, the T 1/2 values were normal or prolonged slightly, mean T1/2 = 76 min +/- 23.

Adolescent↗

Thyrotropin with decreased biological activity, a delayed consequence of cranial irradiation for nasopharyngeal carcinoma.

Patients with TSH of decreased bioactivity have had previous surgery or no known cause (idiopathic). We describe eight patients with nasopharyngeal carcinoma treated with irradiation alone more than 5 yr ago. All had hypothalamic hypothyroidism with low FT4 and normal TSH. Iv TRH gave an exaggerated TSH response, with 60 min greater than 20 min values, without any FT4 or TT3 response at 24 h to the hypersecreted TSH. Radioiodine uptake in 2 patients before and after 3 days of bovine TSH increased from 13 to 31%, and 11 to 28%, respectively. Oral TRH given for 20 days to 5 patients showed a distinctive pattern in serum TSH, FT4 and TT3. Serum TSH rose markedly in the initial few days, dropped to moderate levels for a few days and finally dropped further towards normal values. In contrast, the FT4 and TT3 remained unchanged at hypothyroid levels in the first few days, despite the very elevated TSH; but increased to euthyroid levels and remained higher even while the serum TSH declined further. Direct measurement of TSH bioactivity in FRTL-5 cells in 3 patients showed low values of bioactivity to immunoactivity ratios: 0.4, < 0.2, and 0.35 (NR 0.6-2.1) which increased in 2 patients to 0.9 and 0.8 after 20 days TRH. Serum free alpha-subunit levels were low and unchanged (0.3 to 1.1 micrograms/L) with prolonged TRH. These observations suggest that cranial irradiation may cause hypothalamic hypothyroidism with TSH with decreased bioactivity, and that prolonged TRH administration may restore normal bioactivity.

Adult↗

Evaluation of thyroid nodules for malignancy using 99Tcm-sestamibi.

99Tcm-sestamibi (99Tcm-MIBI) is used for myocardial perfusion imaging but has also been reported to localize in tumours. The usual thyroid scanning radionuclide is 99Tcm-pertechnetate. Altogether, 161 patients with clinically solitary thyroid nodules had both 99Tcm-MIBI and 99Tcm-pertechnetate thyroid scans, with the nodules being reported as cold, warm or hot. Fine-needle aspiration cytology (FNAC) and surgery were performed in those patients who consented to these procedures. Of 131 patients who had FNAC, only 58 proceeded to surgery. In the surgically treated group, 14 of 58 (24%) were confirmed to have thyroid cancer, whereas 44 of 58 (76%) had benign lesions. The 14 cancerous nodules were cold on the 99Tcm-pertechnetate scan, whereas with 99Tcm-MIBI 11 were warm and 3 were either cold or hot nodules. Of the 44 benign lesions, 18 were cold, 9 were warm and 17 were hot nodules. In those 131 patients who had FNAC, the cytology was reported as benign in 120 of the nodules and malignant in 11. The three false-negative cytologies were reported as follicular adenomas. The benign lesions noted on FNAC and surgery were thyroiditis, adenomas and haemorrhagic or colloid cysts. The results from the 58 surgically treated patients suggest that the warm nodules would need surgery, whereas the cold and hot nodules are unlikely to be malignant. The overall sensitivity of the 99Tcm-MIBI scan was 79% and the specificity 80%, with the warm nodule on 99Tcm-MIBI scan having a positive predictive value of 55% and a negative predictive value of 92%.

Adenocarcinoma, Follicular↗

Myocardial perfusion imaging with technetium-99m sestamibi SPECT in the evaluation of coronary artery disease.

Technetium-99m hexakis-2-methoxy-isobutyl-isonitrile (99mTc sestamibi) has been used for myocardial perfusion imaging in the evaluation of coronary artery disease (CAD) since 1990. The experience of its use in an Asian population with and without previous myocardial infarction (MI), diabetes mellitus (DM), hypertension (HPT) and collateral circulation (COL) is reported. One hundred and thirty-nine patients who underwent treadmill exercise testing with 99mTc sestamibi single photon emission computed tomography (SPECT) and coronary angiogram were studied. The overall sensitivity for the detection of CAD was 91.0% and specificity was 64.7%. For patient without previous myocardial infarction, the sensitivity was 83.8% and specificity was 83.3%. Patients with COL had a higher sensitivity while those with HPT had a lower specificity. Sensitivity was higher in patients with multi-vessel disease (MVD) than single vessel disease (SVD). The overall detection for individual artery stenosis was 74.1% with a specificity of 73.1%. Amongst the three major coronary arteries, sensitivity was highest for the right coronary artery and specificity was highest for the left circumflex artery. Specificity was higher in patients without MI or COL. We found that the agreement between 99mTc sestamibi SPECT and coronary angiogram for the extent of CAD was only 52.5%. The concordance rate was higher for patients with MVD than SVD. It is concluded that 99mTc sestamibi SPECT is a sensitive and specific test for the detection of CAD and localization of disease to individual coronary arteries in our patients with some differences in the subgroups. Agreement between coronary angiogram and 99mTc sestamibi for the extent of coronary artery disease was also satisfactory.

Adult↗

Effect of lithium and oral thyrotrophin-releasing hormone (TRH) on serum thyrotrophin (TSH) and radioiodine uptake in patients with well differentiated thyroid carcinoma.

Oral thyrotrophin-releasing hormone (TRH) and lithium were given to patients on follow-up for well-differentiated thyroid carcinoma to see their effect on serum thyrotrophin level (TSH) and radioiodine (I-131) uptake (RAIU). The study was randomised and doubled-blinded and consisted of a total of 19 patients in 3 groups. Group 1 received placebo and TRH, group 2 received lithium and placebo, and group 3 received lithium and TRH. Serum TSH and RAIU at 24 hours were measured before, and after treatment, with TRH, lithium, and/or placebo. In group 1, mean (+/-SEM) TSH increased from 48.9 (+/-15.2) mU/l to 148.2 (+/-48.0) mU/l (p < 0.05); in group 2, the change of 24.9 (+/- 15.9) mU/l to 31.7 (+/-14.1) mU/l in TSH was not statistically significant; and in group 3, TSH increased from 108.1 (+/-13.8) mU/l to 187.0 (+/-39.1) mU/l (p < 0.05). However, despite the significant change in TSH, there was no significant increase in I-131 uptake in any group: 7.70% to 10.43%, 7.15% to 7.43% and 2.49% to 2.61%, in groups 1, 2 and 3 respectively (p > 0.05). We conclude that while oral TRH will increase endogenous serum TSH significantly, there is no significant increase in I-131 uptake. Lithium was not an useful adjunct in increasing serum TSH or I-131 uptake in these patients.

Adenocarcinoma, Follicular↗

Technetium-99m (Tc-99m) diphosphono-propanedicarboxylic acid bone tracer uptake and Tc-99m sestamibi distribution in cardiac amyloidosis--a case report.

It has long been recognised that significant bone tracer localisation in the myocardium is a good indicator for amyloid involvement of the heart in the clinical context of systemic amyloidosis. In this case report, although myocardial tissue diagnosis of amyloidosis was not made, the massive myocardial uptake of bone tracer strongly suggested the presence of amyloid infiltration in the heart, and this finding eventually led to the histological diagnosis of familial amyloid polyneuropathy by skin and sural nerve biopsy. Interesting findings were noted in the single photon emission computerised tomography (SPECT) studies of the myocardium with Technetium-99m diphosphono-propanedicarboxylic acid bone agent and Technetium-99m sestamibi myocardial perfusion agent. Such findings suggest that there is a lack of correlation between the intensity of myocardial uptake of bone tracer and viability of the myocardium, and that amyloid will not deposit in infarcted myocardial tissue.

Amyloid Neuropathies↗