Tailoring of interventional procedures for HCC patients-review article

One of the most frequent primary malignant tumors in the world is hepatocellular carcinoma [HCC]. Currently, the optimal treatment methods for HCC are hepatic resection and liver transplantation. Unfortunately, surgical therapies are suitable for 20% of patients and those who are not eligible for surgery should undergo interventional therapies. In the past decade, a variety of interventional procedures have been employed for local control of hepatocellular carcinoma [HCC] including transcatheter arterial chemoembolization [TACE] and many tumor ablation techniques, such as percutaneous ethanol injection [PEI], radio-frequency ablation [RFA], percutaneous microwave coagulation therapy [PMC], laser-induced interstitial thermotherapy [LITT], cryoablation, and acetic acid injection. By development of new technologies in imaging and drug delivery, it is likely that in the future patients with HCC will be treated by combination therapies to improve patient survival. Computed tomography [CT] and magnetic resonance imaging [MRI] have a crucial role in diagnosis and also follow-up of HCC patients treated by interventional procedures, by which the treatment efficacy, recurrence of disease and certain complications are evaluated. In this review article, we discuss the imaging modalities and also tailoring of interventional procedures for HCC patients

Carotid doppler ultrasonography in preoperative assessment of coronary artery bypass graft surgery in an Iranian population: association between atherosclerosis risk factors and carotid stenosis

The aim of this study was to assess the frequency of significant carotid artery stenosis and its association with the cardiovascular risk factors in a group of Iranian candidates for CABG. Three hundred and one patients with critical coronary artery disease, who were candidates for coronary artery bypass graft [CABG] were evaluated by internal carotid Doppler study. The relations between age, gender, hypertension, diabetes mellitus, smoking, lipid profile, left main coronary stenosis greater than 50% by diameter and coronary artery disease with carotid stenosis were assessed. Significant carotid stenosis greater than 70% was detected in 13 patients [4.3%]. According to the meaningful relationship between significant carotid stenosis and low HDL serum level [lower than 45 in women and lower than 35 in men, p=0.028], hypertension [p=0.021], history of smoking [p=0.026] and left main coronary artery stenosis greater than 50% [p=0.035], they were identified as risk factors valuable enough to guide for selective screening. Among all cardiovascular risk factors. It seems that serum HDL, smoking, left main coronary stenosis and hypertension could be associated with significant carotid artery stenosis in CABG candidates

effect of aging on resting- state brain function: an fMRI study

Healthy aging may be accompanied by some types of cognitive impairment; moreover, normal aging may cause natural atrophy in the healthy human brain. The hypothesis of the healthy aging brain is the structural changes together with the functional impairment happening. The brain struggles to over-compensate for those functional age-related impairments to continue as a healthy brain in its functions. Our goal in this study was to evaluate the effects of aging on the resting-state activation network of the brain using the multi-session probabilistic independent component analysis algorithm [PICA]. We compared the resting-state brain activities between two groups of healthy aged and young subjects, so we examined 30 right-handed subjects and finally 12 healthy aging and 11 controls were enrolled in the study. Our results showed that during the resting-state, older brains benefit from larger areas of activation. While in young competent brains, higher activation occurs in terms of greater intensity. These results were obtained in prefrontal areas as regions with regard to memory function as well as the posterior cingulated cortex [PCC] as parts of the default mode network. Meanwhile, we reached the same results after normalization of activation size with total brain volume. The difference in activation patterns between the two groups shows the brain's endeavor to compensate the functional impairement

Fluoroscopic versus conventional computed tomography-guided biopsy

To determine the success rate of computed tomographic [CT] fluoroscopic CT [FCT] and conventional CT [CCT] for needle navigation in biopsies from mediastinum, bone, abdomen, liver and pelvis. Data from 122 consecutive percutaneous interventional biopsies performed with use of FCT guidance [mean age of 50.5; range: 1-79 years] and 84 consecutive biopsies with CCT guidance [mean age: 50.7; range, 12-83 years] were gathered from the interventional radiologist and general practitioner. The success rate of procedure was increased in the FCT group as compared with that of CCT group in some organs such as bone, abdomen, liver and pelvis. A statistically significant difference was noted when we compared FCT group with CCT in liver biopsies [P=0.019]. The mean procedure time was lower in FCT group. The overall mean [ +/- SD] FCT time was 200 +/- 90 [range: 20-400] sec; in CCT group, it was 420 +/- 260 [range: 605-800] second. FCT facilitates CT-guided biopsy procedures and reduces the procedure time by allowing visualization of the needle tip from skin entrance to the target point

Spatial frequency dependence of the human visual cortex response on temporal frequency modulation studied by fMRI

The brain response to temporal frequencies [TF] has been already reported. However, there is no study on different TF with respect to various spatial frequencies [SF]. Functional magnetic resonance imaging [fMRI] was done by a 1.5 T General Electric system for 14 volunteers [9 males and 5 females, aged 19'26 years] during square-wave reversal checkerboard visual stimulation with different temporal frequencies of 4, 6, 8 and 10 Hz in 2 states of low SF of 0.4 and high SF of 8 cycles/degree [cpd]. All subjects had normal visual acuity of 20/20 based on Snellen's fraction in each eye with good binocular vision and normal visual field based on confrontation test. The mean luminance of the entire checkerboard was 161.4 cd/m2 and the black and white check contrast was 96%. The activation map was created using the data obtained from the block designed fMRI study. Pixels with a Z score above a threshold of 2.3, at a statistical significance level of 0.05, were considered activated. The average percentage blood oxygenation level dependent [BOLD] signal change for all activated pixels within the occipital lobe, multiplied by the total number of activated pixels within the occipital lobe, was used as an index for the magnitude of the fMRI signal at each state of TF and SF. The magnitude of the fMRI signal in response to different TF's was maximum at 6 Hz for a high SF value of 8 cpd; it was however, maximum at a TF of 8 Hz for a low SF of 0.4 cpd. The results of this study agree with those of animal invasive neurophysiologic studies showing SF and TF selectivity of neurons in visual cortex. These results can be useful for vision therapy and selecting visual tasks in fMRI studies