H Baris Diren

Publications (2)5.33 Total impact

• Article: Antidepressant-like effects of echo-planar magnetic resonance imaging in mice determined using the forced swimming test.

  Elif Aksoz, Tolga Aksoz, S Sirri Bilge, Fatih Ilkaya, Suleyman Celik, H Baris Diren
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  ABSTRACT: Echo-planar magnetic resonance imaging (EP-MRI), which is novel variant of MRI, is thought to have antidepressant properties in humans and animal models. Using the forced swimming test (FST), we investigated which monoaminergic system in mice is affected by EP-MRI. The short- and long-term effects of EP-MRI on immobility time in the FST and motor activity within a locomotor activity cage were examined. Two groups of mice underwent 20 min of EP-MRI in an MR scanner (Siemens, 1.5 T Symphony) either 23.5 or 1 h before the start of the second session of the FST. In both groups, the immobility duration in the FST was reduced, similar to effective antidepressant drug treatments. Climbing behavior in the 1-h group and swimming behavior in the 23.5-h group increased significantly, similar to that seen after the administration of desipramine (a noradrenaline reuptake inhibitor) and sertraline (a selective serotonin reuptake inhibitor), respectively. The findings support the hypothesis that EP-MRI has an antidepressant-like effect. We suggest that the antidepressant-like effect begins in the early period with noradrenaline systems and is maintained in the late period with serotonin systems.
  Brain Research 09/2008; 1236:194-9. · 2.73 Impact Factor
• Article: Focal liver lesions: whether a standard dose (0.05 mmol/kg) gadobenate dimeglumine can provide the same diagnostic data as the 0.1 mmol/kg dose.

  Mehmet Selim Nural, Erkan Gokce, Murat Danaci, Ilkay Koray Bayrak, H Baris Diren
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  ABSTRACT: Gadobenate dimeglumine (Gd-BOPTA) is a liver-specific contrast agent also showing a distribution in the extracellular compartment which is recommended to be used at standard dose (0.05 mmol/kg) in magnetic resonance imaging (MRI) of liver lesions. However, its use at 0. 1mmol/kg is gradually increasing in recent clinical practice. Which dose should we use in routine MRI of liver lesions from now on? This study investigated the efficacy of Gd-BOPTA at a standard dose versus 0.1 mmol/kg dose in demonstrating diagnostic data in MRI of focal liver lesions. The study included 47 patients with focal liver lesions. Twenty-two patients received standard dose and 25 patients received 0.1 mmol/kg dose Gd-BOPTA intravenously. MRI of both groups was carried out with T1-A FLASH-2D and T2-A TURBO spin echo before contrast injection and T1-A FLASH-2D sequences in dynamic and late phase (90th minute) after the contrast injection. The lesion conspicuity for each image was evaluated qualitatively. Liver signal to noise ratio (SNR), absolute lesion-liver contrast to noise ratio (CNR), mean lesion-liver CNR and contrast enhancement rate of the liver obtained from both groups were compared quantitatively. While liver contrast enhancement rate in the group receiving standard dose Gd-BOPTA were 41%+/-42 in the arterial phase, 66%+/-58 in the portal phase, 45%+/-45 in the venous phase and 42%+/-88 in the late phase, these values were 43%+/-59, 86%+/-73, 63%+/-75 and 61%+/-105, respectively, in the group receiving the dose of 0.1 mmol/kg. There were no statistically significant differences between the means of both groups. While the absolute lesion-liver CNR values were 18+/-15 precontrast, 22+/-18 in the arterial phase, 19+/-17 in the portal phase, 15+/-10 in the venous phase and 24+/-26 in the late phase in the group receiving the standard dose Gd-BOPTA, these values were 13+/-11, 18+/-15, 15+/-15, 13+/-13 and 19+/-21, respectively, in the group receiving the 0.1 mmol/kg dose. There were no statistically significant differences between the means of both groups (p>0.05). However, when the mean lesion-liver CNR values were compared, there was statistically significant difference between each arterial and portal phases of metastases in both groups (p<0.05). There was no statistical difference found in other lesions. When lesion conspicuity scores were compared, there were no significant differences between the two groups. In liver lesions, similar diagnostic data are obtained in dynamic and late phase MRI with either standard dose Gd-BOPTA or with a dose of 0.1 mmol/kg. Because there was a difference in only metastases in both groups, in oncological patients who are being investigated for liver metastasis, it is expedient to use a dose of 0.1 mmol/kg.
  European Journal of Radiology 04/2008; 66(1):65-74. · 2.61 Impact Factor