Biomedical subjects

Mohsen Saghari

Publications and source records attributed to Mohsen Saghari.

10 recordsLinked to original sources

PubMed2007

A correlative study comparing current different methods of calculating left ventricular ejection fraction.

BACKGROUND: Left ventricular ejection fraction (EF) is a major determinant of survival in patients with coronary artery disease (CAD). Comparative accuracy of numerous modalities in calculating EF is not well investigated. METHOD: We compared EF as calculated by rest and post-stress Cedars automated quantitative gated SPECT (AQGS), rest and post-stress semi-automatically processed gated SPECT (MQGS), echocardiography and contrast ventriculography (LVG) to those determined by rest and post-stress cavity-to-myocardium ratio (CMR) in 109 patients. Gated SPECT was performed based on a 2-day protocol using Tc-MIBI. RESULTS: Mean EF in LVG, echo, post-stress CMR, rest CMR, post-stress AQGS, rest AQGS, post-stress MQGS and rest MQGS were 41.8%+/-12.1, 44.8%+/-11.8, 38.1%+/-10.7, 35.7%+/-12.1, 44.5%+/-15.1, 46.9%+/-14.7, 40.1%+/-14.3 and 43.5%+/-14.3 respectively. Although significant differences were observed between some of these methods, good and excellent linear correlations were present among values (all Pearson correlations >0.63). Considering LVG as the 'gold standard', we defined two groups: EF <35% (class 1) and >35% (class 2). Discriminant analysis showed that SPECT has the ability to predict patients' classes. In 4/18 of patients with normal SPECT (on both visual and quantitative analyses, SSS <4), EF on QGS showed a significant decrease on post-stress compared with rest. CONCLUSION: There is a good correlation in calculating EF by LVG, QGS and echocardiography, regardless of EF value. Whenever QGS is impossible, CMR is a reliable indirect indicator of EF. Gating of both phases (and when impossible, CMR of both phases) has an additional value in diagnosis of CAD.

Adult↗

PubMed2006

Myocardial perfusion abnormalities in chemical warfare patients intoxicated with mustard gas.

BACKGROUND: Mustard agents are of the major chemical agents used during Iran-Iraq war. There are no reports concerning long-term cardiac effects. The aim was to assess the scintigraphic pattern of myocardial perfusion in patients intoxicated with blistering gases. METHOD: We analyzed myocardial perfusion scans of 22 consecutive intoxicated patients (21 male and 1 female, all < 44 years) and compared results with 14 controls. Only those patients and controls were entered whose 10-year risk of coronary artery disease (Framingham criteria) was <5%. Also only those patients were experimented upon that had currently other confirmed complications of intoxication (respiratory, cutaneous and ocular complications). All patients underwent a 1-day stress and rest protocol using (99m)Tc-MIBI. Images were assessed visually and quantitatively using Cedars Sinai program. RESULTS: The prevalence of nonhomogeneity of uptake and left and right ventricular enlargement in both visual and quantitative analyses were higher in the mustard exposed patients than unexposed controls. The prevalence of ischemia was higher in the exposed patients (P < 0.05). Cavity to myocardium ratio, as an established and validated measure of ejection fraction, was also significantly lower in the warfare patients than the controls. CONCLUSION: In so far it lies in our knowledge, this is the first report concerning the scintigraphic pattern of myocardial perfusion in mustard intoxicated patients. Based on the results, the pattern of myocardial perfusion in these patients is significantly different from normal controls, which could resemble either coronary artery disease or mild cardiomyopathic changes.

Adult↗

PubMed2006

Frequency and severity of myocardial perfusion abnormalities using Tc-99m MIBI SPECT in cardiac syndrome X.

BACKGROUND: Cardiac syndrome X is defined by a typical angina pectoris with normal or near normal (stenosis <40%) coronary angiogram with or without electrocardiogram (ECG) change or atypical angina pectoris with normal or near normal coronary angiogram plus a positive none-invasive test (exercise tolerance test or myocardial perfusion scan) with or without ECG change. Studies with myocardial perfusion imaging on this syndrome have indicated some abnormal perfusion scan. We evaluated the role of myocardial perfusion imaging (MPI) and also the severity and extent of perfusion abnormality using Tc-99m MIBI Single Photon Emission Computed Tomography (SPECT) in these patients. METHODS: The study group consisted of 36 patients with cardiac syndrome X. The semiquantitative perfusion analysis was performed using exercise Tc-99m MIBI SPECT. The MPI results were analyzed by the number, location and severity of perfusion defects. RESULTS: Abnormal perfusion defects were detected in 13 (36.10%) cases, while the remaining 23 (63.90%) had normal cardiac imaging. Five of 13 (38.4%) abnormal studies showed multiple perfusion defects. The defects were localized in the apex in 3, apical segments in 4, midventricular segments in 12 and basal segments in 6 cases. Fourteen (56%) of all abnormal segments revealed mild, 7(28%) moderate and 4 (16%) severe reduction of tracer uptake. No fixed defects were identified. The vessel territories were approximately the same in all subjects. The Exercise treadmill test (ETT) was positive in 25(69%) and negative in 11(30%) patients. There was no consistent pattern as related to the extent of MPI defects or exercise test results. CONCLUSION: Our study suggests that multiple perfusion abnormalities with different levels of severity are common in cardiac syndrome X, with more than 30 % of these patients having at least one abnormal perfusion segment. Our findings suggest that in these patients microvascular angina is probably more common than is generally believed.

Journal Article↗

PubMed2006

Efficacy of radioiodine therapy in the treatment of elevated serum thyroglobulin in patients with differentiated thyroid carcinoma and negative whole-body iodine scan.

INTRODUCTION: In the management of patients with differentiated thyroid carcinoma, serum thyroglobulin levels are often well correlated with whole-body radioiodine scanning (WBS) results. However, occasionally, a mismatched result - increased thyroglobulin with negative WBS - is observed. Radioiodine therapy has been suggested as a therapeutic choice with controversial results. METHOD: We studied 32 differentiated thyroid carcinoma patients with elevated thyroglobulin level and negative WBS who had been treated with high-dose radioiodine. With a mean follow-up of 25.6 months (all follow-ups >11 months), thyroglobulin and thyroid-stimulating hormone levels, WBS, clinical, radiographic and pathological findings following treatment were recorded. RESULTS: The mean pre-therapy off-treatment thyroglobulin was 152 +/- 119.0 ng.ml(-1). Although there was a mild trend towards an increase in thyroglobulin in the first post-treatment year, the difference was not significant. At the end of the follow-ups, 22 patients (68.7%) were categorized as non-responders to radioiodine therapy (any change or elevation of thyroglobulin or radiological and pathological evidences of progression), four patients (12.5%) as partial responders (transient reduction but not a normalization of thyroglobulin) and six patients (18.7%) as responders (normalization of thyroglobulin with no evidence of remnant disease). In nine of 10 partial and complete responders, reduction or normalization of thyroglobulin had occurred in the first post-treatment year. CONCLUSION: We recommend that in differentiated thyroid carcinoma patients with elevated thyroglobulin and negative WBS, at least one course of radioiodine therapy should be undertaken and if reduction or normalization of serum thyroglobulin is not achieved, repeated courses of radioiodine therapy are not logical and other therapeutic methods should be applied.

Adolescent↗

PubMed2005

A preliminary study of neuroSPECT evaluation of patients with post-traumatic smell impairment.

BACKGROUND: Most olfactory testings are subjective and since they depend upon the patients' response, they are prone to false positive results. The aim of this study was to use quantitative brain perfusion SPECT in order to detect possible areas of brain activation in response to odorant stimulation in patients with post-traumatic impaired smell in comparison to a group of normal subjects. METHODS: Fourteen patients with post-traumatic impaired smell and ten healthy controls were entered in this prospective study. All subjects underwent brain SPECT after intravenous injection of 740-MBq 99mTc-ECD and 48 hours later, the same procedure was repeated following olfactory stimulus (vanilla powder). RESULTS: In most of seven regions of interest (Orbital Frontal Cortex, Inferior Frontal Pole, Superior Frontal Pole, Posterior Superior Frontal Lobe, Parasagittal Area, Occipital Pole, and Cerebellar area) the post-stimulation quantitative values show increased cortical perfusion being more pronounced in normal volunteers than the anosmic patients (except cerebellar areas and the right occipital pole). Maximal activation was observed in orbitofrontal regions (right+ 25.45% and left +25.47%). CONCLUSION: Brain SPECT is a valuable imaging technique in the assessment of post-traumatic anosmia and could be competitive as an alternative to other imaging techniques, especially when functional MRI is unavailable or unsuitable. However, this procedure may benefit from complementary MRI or CT anatomical imaging.

Journal Article↗

PubMed2005

Comparison of SPECT bone scintigraphy with MRI for diagnosis of meniscal tears.

BACKGROUND: Scintigraphy has been considered as competitive to MRI, but limited data are available on the accuracy of single photon emission tomography (SPECT) compared with MRI for the assessment of meniscal tears. Our objective was to assess the value of SPECT in comparison to MRI. METHODS: Between January 2003 and March 2004, sixteen patients were studied with both modalities and the accuracy rates of SPECT scan results, and MRI findings in the diagnosis of meniscal tears were compared. Arthroscopy was the gold standard. RESULTS: The respective sensitivity rate, specificity rate, and positive and negative predictive accuracies of MRI were 89%, 94%, 93%, and 79% and for SPECT those were 78%, 94%, 94%, and 88%. There was good agreement on the presence or absence of tears between two modalities (κ statistic = 0.699). CONCLUSION: SPECT and MRI are both valuable imaging techniques. SPECT is a useful alternative when MRI is unavailable or unsuitable and it is beneficial when more possible accuracy is desired (such as when MRI results are either inconclusive or conflict with other clinical data).

Journal Article↗

PubMedDate not supplied

Brain perfusion single photon emission computed tomography findings in patients with posttraumatic anosmia and comparison with radiological imaging.

BACKGROUND: Different techniques in neuroimaging have been proposed for assessment of olfactory dysfunction but they are not without limitations. Recently, some studies showed the usefulness of single photon emission-computed tomography (SPECT) in evaluation of patients with posttraumatic anosmia. This study was designed to assess the possible diagnostic value of SPECT findings in patients with posttraumatic anosmia in comparison with magnetic resonance imaging (MRI)/CT imaging. METHODS: Sixteen patients who had head trauma and consequently anosmia, which was defined according to Cain's identification test, were included in this study. Two nonanosmic groups, traumatic patients and nontraumatic healthy individuals, were selected as control groups for this study. Qualitative and semiquantitative brain perfusion SPECT was performed by measuring the uptake ratio of the orbital frontal cortex to occipital pole in the sagittal projections (uptake index). All 16 target patients had a previous CT scan and/or MRI. Semiquantitative and qualitative brain perfusion SPECT were compared with radiological imaging. RESULTS: Semiquantitative assessment of brain perfusion SPECT revealed remarkable orbital frontal hypoperfusion as compared with two control groups. 87.5% of anosmic patients showed orbital frontal hypoperfusion (-2 SD below the lowest level in healthy controls). In addition, the semiquantitative SPECT method detected more orbitofrontal abnormality than the qualitative method or radiological imaging (MRI and/or CT). CONCLUSION: Findings suggest that by using SPECT, posttraumatic anosmia corresponds to the hypoperfusion in the orbital frontal cortex in a great number of patients. Because of its availability, rather low cost, technical ease, and possibility to obtain objective quantitative information, brain perfusion SPECT can be complementary to other diagnostic techniques in the evaluation of olfactory function, although additional neurophysiological and imaging studies are needed.

Adult↗

PubMedDate not supplied

Comparative evaluation of two fixed doses of 185 and 370 MBq 131I, for the treatment of Graves' disease resistant to antithyroid drugs.

Radioiodine (131I) treatment is often applied for the treatment of Graves' disease (GD). The optimal dose of 131I for Graves' hyperthyroidism is debated. Various techniques suggest either fixed doses or varying doses based on elaborate calculations of the gland size, 131I uptake, and 131I turnover. Fixed dose regimens avoid dose calculations but there is no consensus on the actual dose to be administered. We compared two routinely recommended fixed 131I doses of 185 and 370 MBq for this purpose. Fifty nine patients with GD who had not been previously treated with 131I were randomized in two groups. Group A consisted of 33 patients who were treated with 185 MBq of 131I. Group B consisted of 26 patients who were treated with 370 MBq of 131I. Group A patients were 21% male and 78% female, mean age 38.1+/-14.4, range 15 to 77 y. Group B patients were 27% male and 73% female, mean age 40.7+/-11.7, range 27 to 72 y. All patients were reexamined every six months for two years. The following clinical outcomes were noticed: a) Persistent hyperthyroidism, which was considered as failure to treatment, requiring further 131I treatment. b) Hypothyroidism; requiring life-long replacement treatment. c) Euthyroid state. Euthyroid and hypothyroid states were considered as a response to treatment of hyperthyroidism. In Group A, 10 patients (30.3%) became euthyroid and 6 (18.2%) hypothyroid (an overall response of 48.5%), while 17 (51.5%) remained hyperthyroid by the end of the follow-up period. In Group B, 10 patients (38%) became euthyroid and 13 (50%) hypothyroid, an overall response of 88.5%. Non responders were 3 patients (11.5%). No correlation was noted between the outcome of treatment and age, sex, size of the thyroid gland or thyroid uptake in each Group of patients, while a significant correlation was noted between the disease outcome and the amount of administered 131I (P<0.003). The incidence of hypothyroidism by the end of two years of follow up was less in Group A than in Group B and the incidence of non responders to treatment was lower in Group A. In view of the higher cost of treatment, the longer time elapsing to treatment, the number of office visits by the patients and the higher number of patients with persistent hyperthyroidism in Group A, we conclude that a fixed dose of 131I of 370 MBq is more useful and effective for the treatment of GD as compared to 185 MBq of 131I.

Adult↗

PubMedDate not supplied

The value of 99mTc-MIBI whole body scintigraphy in active and in remission multiple myeloma.

Technetium-99m methoxy-isobutyl-isonitrile (99mTc-MIBI) has been proposed as an in-vivo marker of various active malignant diseases. The goal of this study was to evaluate the 99mTc-MIBI whole body scintiscan for the early detection of multiple myeloma (MM), active or in remission. We have studied 43 patients with MM, 32 men and 11 women aged 52+/-10 years. Group A patients had active MM disease (29 cases) and Group B patients had MM disease in remission (14 patients). Plasma proteins, serum immuno-electrophoresis, bone marrow biopsy, whole body 99mTc-MIBI scan and serum bio-chemical tests (ESR, and serum alkaline phosphatase) were carried out in each patient for the diagnosis of active or relapsed disease, or remission. Clinical and laboratory evaluation was made by two oncologists. Scintigraphic images were interpreted by three nuclear physicians who were blinded to the patients' clinical condition. The extension scale of the lesions on scintigraphy (E-score) was categorized into E0-E3. The intensity of radiotracer uptake throughout the skeleton (I-score) was also classified from I0-I3 as compared to the intensity of myocardial uptake. All patients were followed for at least one year and reassessed by the end of the year for confirming active-relapsed disease or remission. One-way analysis of variances and Spearman correlation coefficient were used for statistical data analysis. The sensitivity, specificity, positive and negative predictive values and accuracy of the 99mTc-MIBI scan for determining active or relapsed cases were: 69%, 100%, 100%, 61% and 79%, respectively. There were significant differences in scan pattern, intensity, and extension of the lesions in patients with active-relapsed disease versus those in remission (P<0.001). It is concluded that the pattern of extension and intensity of 99mTc-MIBI uptake in MM patients is associated with disease activity. Hence, in addition to the hematological and pathological findings, the 99mTc-MIBI scan may be considered as a relatively accurate non-invasive technique for the differential diagnosis of active-relapsed from in remission MM.

Female↗

PubMedDate not supplied

Gonadal function in patients with differentiated thyroid cancer treated with (131)I.

The aim of this study was to evaluate the effect of treatment with radioactive iodine ((131)I) on gonadal function in males and females with follicular or papillary thyroid carcinoma. Consenting patients at reproductive age were grouped according to the cumulative dose of (131)I received and followed-up for at least 12 months. Overall, 246 patients (159 females, 87 males) were studied. In all males, serum levels of follicle-stimulating hormone (FSH), luteinising hormone (LH), and testosterone were measured before radioiodine treatment and 2, 6 and 12 months afterwards; fifty-three of all patients underwent semen analysis also. On females, tests for serum levels of LH, FSH, estrogen, and progesterone were performed. In 87.4% of males, there was an increase in serum FSH level after (131)I treatment and in 20.7% of them this level remained high during the follow-up period. The average serum level of FSH 2-6 months after each course of treatment was significantly higher than before treatment (p<0.01), and there was a significant correlation with the cumulative dose of (131)I received (p<0.001). Reduced sperm count was found in 35.8% of the male patients, among whom 73.7% also showed reduced motility. In 36.8% of the patients with reduced sperm count (13.2% of the total), this finding was persistent during the follow-up period. Increased level of FSH was correlated with reduced sperm count in all doses (p<0.005). There was no significant correlation between serum levels of LH and testosterone with (131)I treatment in males. In females, no significant correlation between gonadal-hypophyseal hormones and treatment with (131)I was found, and there were no signs and symptoms of sexual dysfunction. Infertility was not noticed in any patient neither was there any case of abortion. Although female gonads are resistant to radioiodine treatment for thyroid cancer, in males this treatment may result in impairment of the gonadal function, which is transient most of the times. Spermatogenesis is especially sensitive to the radiation effect of (131)I treatment, and this effect is related to the cumulative radioiodine dose. To reduce gonadal complications, especially in males, treatment with (131)I should use the lowest possible doses. Also all necessary measures should be taken to reduce radiation dose to gonads.

Journal Article↗