مجله دانشکده پزشکی اصفهان
پیاپی 391 (هفته سوم شهریور 1395)

Human visual perception in detection of an object from background is based on edge emission and contrast. The optical aberration is the main factor to degrade quality of image in the eye. People with this complication perceive images with low levels of contrast and distorted edges. Since the conventional methods are cumbersome, the new complementary method such as Pre-compensation is offered for display devices. In this research we investigate quantitative effect of the contrast between the object and the background to reduce the effect of low order optical aberration by increasing regional contrast. We tried to find out which contrast level could improve visual acuity in Weber-contrast.
In this Research, 12 optical charts with different levels of contrast were designed based on the log MAR standard. Then obtained patterns were tested on 20 patients with low order optical aberrations. The results of each chart were analyzed using SPSS software.
Findings: There was a significant difference in visual acuity of persons at different contrast levels. But, when the Weber contrast percent was low, the difference was not remarkable.
Based on the obtained results, a background with lower contrast improves visual acuity approximately up to 11% in the log MAR scale. Therefore, to improve visual acuity in display devices, foreground is more appropriate that be in higher state of brightness than background.

Most radioactive materials used in nuclear medicine are gamma emitter. Gamma range is relatively high, so the nuclear medicine technologists are exposed to external exposure by gamma. This study aimed to estimate nuclear medicine technologist dose at the time of injection of radiotracer 99mTC-MIBI and time of patients heart scan.
This survey was done on nuclear medicine technologist in Chamran Hospital, Isfahan, Iran. Received dose was measured with digital pocket dosimeter that was calibrated by Iranian Atomic Energy Agency. Dosimeter measured the dose while it was on collective dose with microsievert unit. Data were analysed with SPSS and Excel software.
Findings: The technologist received more dose during injection of 99mTC-MIBI and myocardial perfusion imaging (MPI), 0.36 ± 0.073, 0.24 ± 0.07 microsievert per patient scan, respectively.
The results of this study were in good agreement with other studies. According to this result, technologist who is responsible for injection received 30% more than who is responsible for imaging; so rotation shift for technologists is essential.

This study aimed to compare the results of lower extremity electrodiagnostic findings before and after lumbar disc herniation surgery.
In a clinical trial study during 2015-2016, 30 patients with single disk herniation and lumbar disc surgery were selected and electromyogram (EMG) and nerve conduction velocity (NCV) test were done for them before and 4 weeks after the surgery; findings of before and after operation were compared.
Findings: Latency parameter on both, the left and right lower limbs decreased significantly. In contrast, amplitude and velocity parameters increased in both right and left lower limbs. The velocity amplitude significantly increased in both right and left lower limbs. Four parameters, positive sharp wave, and amplitude, duration and potential of polyphasic wave in gluteus maximus and antetibialis muscles significantly decreased after the surgery; but, the percent of recruitment reduction in these muscles was not significant. All these five parameters in the gastrocnemius and vastus medialis muscles and also limb progressive supranuclear palsy (PSP) significantly decreased.
Electerodiagnostic and electromyography findings can show nerve roots engagement in pre- and post-operation periods; and therefore, discectomy in patients with postoperative pain or discomfort caused by the presence or recurrence of neurologic involvement complain, to determine the involvement and pressure on the spinal nerve roots, can be used this method to determine the source of pain in these patients.

This study aimed to the relationship of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) with an uncertain prognosis for the patients admitted to the intensive care unit (ICU) in Alzahra Hospital, Isfahan, Iran, during 2014-2015.
In a cross-sectional study, 100 patients admitted in intensive care units of Alzahra hospital were selected and within five days, C-reactive protein level and erythrocyte sedimentation rate were measured. In addition, all the patients were studied for incidence of delirium.
Findings: During 5 days of hospitalization, 46 patients were suffering from delirium. The mean erythrocyte sedimentation rate in the two groups with and without delirium was 9.11 ± 2.00 and 8.73 ± 2.02 millimeter per hour, respectively, and there was no significant difference between the two groups (P = 0.340). Mean serum C-reactive protein level in two groups with and without delirium was 12.20 ± 6.06 and 9.55 ± 4.27, respectively (P = 0.012).
Changes in the level of inflammatory markers such as C-reactive protein in patients during hospitalization in intensive care units, especially in the first days of hospitalization and in the elderly, can be a good indicator for predicting the incidence of delirium. But, considering the differences in various studies, we recommend that more studies with larger sample sizes should be conducted.

This study aimed to investigate the properties of adding fentanyl or sufentanil to intrathecal Marcaine on sensory and motor block, intraoperative hemodynamic status and reducing of pain in patients after lumbar disc surgery and compare it with the control group.
In a clinical-trial study, 96 patients undergoing lumbar disc surgery with spinal anesthesia were distributed in three groups of 32 people. Fentanyl and sufentanile were added to Marcaine in the first and second group, respectively, and in the third group, only Marcaine was injected. The severity of postoperative pain, the analgesic requirement and time of first receiving the drug and drug intake in the three groups were determined and compared during 24 hours after the surgery.
Findings: During the stay of fentanyl, sufentanil and control groups in recovery, 40.6, 6.3 and 59.4 percent of the patients had pain in the groups, respectively, and there were significant differences among the three groups (P The results of this study showed that using fentanyl or sufentanil with Marcaine led to reduced incidence and severity of postoperative pain after lumbar disc surgery and thus reduction in opioid usage.