Hatice Durak

Water-pipe smoking effects on pulmonary permeability using technetium-99m DTPA inhalation scintigraphy

ObjectiveAlthough extensive work has been done on cigarette smoking and its effects on pulmonary function, there are limited number of studies on water-pipe smoking. The effects of water-pipe smoking on health are not widely investigated. The aim of this study was to determine the effects of water-pipe smoking on pulmonary permeability.MethodsTechnetium-99m DTPA inhalation scintigraphy was performed on 14 water-pipe smoker volunteers (all men, mean age 53.7 ± 9.8) and 11 passive smoker volunteers (1 woman, 10 men, mean age 43.8 ± 12). Clearance half-time (T 1/2) was calculated by placing a monoexponential fit on the time activity curves. Penetration index (PI) of the radioaerosol was also calculated.ResultsPI was 0.58 ±0.14 and 0.50 ± 0.12 for water-pipe smokers (WPS) and passive smokers (PS) respectively. T1/2 of peripheral lung was 57.3 ± 12.7 and 64.6 ± 13.2 min, central airways was 55.8 ± 23.5 and 80.1 ± 35.2 min for WPS and PS, respectively (p ≤ 0.05). FEV1/FVC% was 82.1 ± 8.5 (%) and 87.7 ± 6.5 (%) for WPS and PS, respectively (0.025 < p ≤ 0.05).ConclusionsWe suggest that water-pipe smoking effects pulmonary epithelial permeability more than passive smoking. Increased central mucociliary clearance in water-pipe smoking may be due to preserved humidity of the airway tracts.

Technetium-99m HMPAO brain SPECT in children with attention deficit hyperactivity disorder

Attention deficit hyperactivity disorder (ADHD) is a developmental, neurobehavioral syndrome with an onset in childhood. The aim of this study was to investigate the existence of regional perfusion changes in ADHD by means of Tc-99m HMPAO brain SPECT. Thirteen children with a diagnosis of ADHD and 7 healthy, age-matched controls were included in this study. Hypoperfusion was observed on the right temporal cortex in 9, and on the left temporal cortex in 3 children. The distribution of the lesions showed right lateral temporal cortex involvement in 3, right medial temporal cortex in 9 and left medial temporal cortex in 8 children. The distribution of the lesions showed right lateral temporal cortex involvement in 3, right medial temporal cortex in 9 and left medial temporal cortex in 8 children. Asymmetric perfusion was seen on the caudate nucleus in 4, on the thalamus in 3 and on the frontal cortex in 6 children. There was a significant difference between children with ADHD and controls in right medial temporal cortex: cerebellum and righ lateral temporal cortex: cerebellum ratios. Hypoperfusion in the right medial temporal cortex was significantly and inversely correlated with Du Paul teachers’ questionnaire rating scale (r=−0.71, p=0.0006). It has been postulated that difficulty in self regulating response to stimuli in ADHD is mediated by underfunctioning of the orbital frontal cortex and subsequent connection to the limbic system. Decreased temporal cortex perfusion may dysfunction of the limbic system or the orbito-frontal-limbic axis.

99mTc-MIBI scintigraphy in metastatic renal cell carcinoma: clinical validation of the relationship between99mTc-MIBI uptake and P-alvcoprotein expression in tumour tissue

Technetium-99m hexakis-2-methoxyisobutyl-isonitrile (MIBI) and thallium-201 imaging was performed in a patient with metastatic renal cell carcinoma (RCC), which is a well-known tumour type demonstrating P1-glycoprotein (PGP) overexpression. Two scintigraphic patterns - TI(+)/MIBI(−) in primary tumour and TI(+)/MIBI(+) in metastatic tumour — were observed, suggesting high- and low-level PGP expression, respectively. Immunochemical study for PGP revealed strong staining of the primary tumour cells. This case clinically validates the previously suggested relationship between99mTc-MIBI uptake and PGP expression.

Technetium-99m HMPAO brain SPECT in autistic children and their families

The purpose of the study was to investigate perfusion patterns in autistic children (AC) and their families. Ten AC (9 boys, 1 girl; mean age: 6.9+/-1.7 years) with autistic disorder defined by DSM-III-R criteria, five age-matched children (3 boys, 2 girls) as a control group, and the immediate family members of eight AC (8 mothers, 8 fathers, 7 siblings; mean ages: 39+/-4 years, 36+/-5 years and 13+/-5 years, respectively) were included in the study. Age- and sex-matched control groups for both the parents and the siblings were also included in the study. Brain perfusion images were obtained 1 h after the intravenous injection of an adjusted dose of Tc-99m HMPAO to children and the adults. Visual and semiquantitative evaluations were performed. Hypoperfusion was seen in the right posterior parietal cortex in three AC, in bilateral parietal cortex in one AC, bilateral frontal cortex in two AC, left parietal and temporal cortex in one AC, and right parietal and temporal cortex in one AC. Asymmetric perfusion was observed in the caudate nucleus in four AC. In semiquantitative analyses, statistically significant hypoperfusion was found in the right inferior and superior frontal, left superior frontal, right parietal, right mesial temporal and right caudate nucleus. In parents of AC, significant hypoperfusion was noted in the right parietal and bilateral inferior frontal cortex. In siblings of AC, perfusion in the right frontal cortex, right nucleus caudate and left parietal cortex was significantly decreased. This preliminary study suggests the existence of regional brain perfusion alterations in frontal, temporal, and parietal cortex and in caudate nucleus in AC and in their first-degree family members.

Early and delayed thallium-201 scintigraphy in thyroid nodules: the relationship between early thallium-201 uptake and perfusion.

Seventy-six patients with thyroid nodules were studied. Initially, 74 MBq of thallium-201 was injected. The thyroid gland was imaged 15 min (early) and 3 h (delayed) after the injection. Thereafter, 185 MBq technetium-99m pertechnetate was injected. Immediately after the injection, a 1-min perfusion image was acquired, followed by an image at 20 min. Increased early and delayed201Tl uptake compared with the contralateral thyroid tissue was adopted as the criterion for malignancy. Sensitivity, specificity and negative predictive values were found to be 85%, 64% and 78%, respectively, in operated patients, but these values were 86%, 87% and 95%, respectively, in the whole group, including patients followed with fine-needle aspiration biopsy. With the purpose of investigating the relationship between perfusion and early201Tl uptake, both perfusion and early images were graded comparing nodular activity with contralateral thyroid activity. There was a poor correlation between perfusion and201Tl uptake. The correlation was even worse in hyperactive nodules. It is concluded that early and delayed201Tl imaging should not be used in the differential diagnosis of cold nodules and that early201Tl uptake seems to be more closely related to factors other than perfusion.

Results of the gastroesophageal reflux assessment in wheezy children

Gastroesophageal reflux (GER) is implicated in the pathogenesis of respiratory symptoms in childhood. It should be taken into account especially in the differential diagnosis of children presenting with wheezing.Although, oesophageal pH monitorisation has been reported to be the best technique in the evaluation of GER, radionuclide studies have also been shown to be very sensitive recently. In this study, 82 children presenting with recurrent wheezing (n=74) and/or vomiting (n=28) (mean age 17.4 months; range 3–48 months) were evaluated. GER scintigraphy was performed to determine the frequency of GER. GER was determined in 18 of the 82 cases (21.9%). The GER was found in 21.1% of children with recurrent wheezing and in 16.6% of children suffering from recurrent vomiting.GER scintigraphy should be kept in mind in the evaluation of children with the complaint of recurrent wheezing since it is a noninvasive and easily applicable method.

New radiolabeled CCK-8 analogues [Tc-99m-GH-CCK-8 and Tc-99m-DTPA-CCK-8]: preparation and biodistribution studies in rats and rabbits

The aim of this study is to label CCK-8 with Tc-99m and to investigate its radiopharmaceutical potential. CCK-8 was labeled with Tc-99m using GH and DTPA as bifunctional chelating agents. Labeling efficiency was higher than 99%. Complex was stable more than 5 hours at room temperature. 37 MBq Tc-99m-GH-CCK-8 or Tc-99m-DTPA-CCK-8 was administered intravenously to rabbits for biodistribution experiments. Dynamic and static images were obtained from anterior projection using a Camstar XC/T gamma camera. For quantitative evaluation, regions of interest were drawn on organs and time-activity curves were generated. The highest accumulation occurred in brain within 10 and 30 minutes after injection. Renal and hepatobiliary excretion were observed. Brain distribution studies in rats showed the highest activity was in hypothalamus. Results demonstrated that Tc-99m-GH-CCK-8 and Tc-99m-DTPA-CCK-8 analogs may be a useful new class of receptor-binding peptides for diagnosis and therapy of brain diseases related with CCK-B receptor-expressing tumors.

Tc-99m-HMPAO uptake by bronchoalveolar cells.

Lung uptake of intravenously injected Tc-99m-HMPAO is observed in smokers and in lung toxicity due to various agents. We investigated the Tc-99m-HMPAO uptake of bronchoalveolar lavage (BAL) cells in the lungs after incubation inin vitro conditions (6 patients), intravenous injection (IV) (7 patients) and inhalation (INH) (6 patients) of Tc-99m-HMPAO in order to show whether BAL cells are also responsible for Tc-99m-HMPAO uptake in the lungs. Cell/supernatant (C/S) count ratio was 7.0±3.5, 29.3±40.8 and 8.4±4.5 forin vitro, IV and INH groups, respectively. C/Sin vitro showed a positive correlation with % alveolar macrophages (r=0.943, p=0.0048) and a negative correlation with % neutrophils (r=−0.945, p=0.0045). Cells/whole BAL fluid ratio correlated with the amount of daily cigarette consumption in INH group (r=0.95, p=0.0037). Tc-99m-HMPAO showed adherence to mucus after inhalation. Tc-99m-HMPAO diffuses into alveolar spaces after, injection and is present in BAL fluid and BAL cells both after injection and inhalation. Glutathione concentration and oxido-reductive state of the epithelial lining fluid and BAL cells may influence the lung uptake of Tc-99m-HMPAO.

The role of Tc-99m RBC scintigraphy in the differential diagnosis of orbital cavernous hemangioma

The cavernous hemangioma is the most common benign orbital tumor in adults. Its presentation is during the forth to fifth decades with a slowly progressive unilateral proptosis. Intraconal cavernous hemangiomas may be difficult to differentiate from other intraconal lesions such as schwannomas, meningiomas and hemangiopericytomas. We report a case of orbital cavernous hemangioma diagnosed by Tc-99m RBC scintigraphy. Tc-99m RBC scintigraphy revealed a typical scintigraphic pattern in which there is intense focally increased uptake on the delayed image. We conclude that Tc-99m RBC scintigraphy can be a useful method in the differential diagnosis of orbital cavernous hemangioma as in hepatic hemangioma.

Landau-Kleffner syndrome : Relation of clinical, EEG and Tc-99m-HMPAO brain SPECT findings and improvement in EEG after treatment

Landau-Kleffner syndrome (LKS) is a rare childhood disorder characterized by acquired aphasia with seizures and electroencephalogram (EEG) abnormalities. Tc-99m-HMPAO SPECT was performed in three right handed children with LKS. A relative decrease in perfusion was found in the left temporal cortex of all three patients and also in the left frontoparietal cortex of one patient with hyperkinetic behavior. Degree of regional cerebral perfusion impairment did not correlate with the severity of clinical and EEG abnormalities. Asymmetrical temporoparietal perfusion appears characteristic of LKS. SPECT findings in LKS were evaluated as useful in elucidating the pathogenic features of the disorder in the brain.