No abstract

Objective To systemically explore the range of visual angles that affect visual acuity, and to establish the relationship between the P1 component (peak latency ~100 ms) of the pattern-reversal visual-evoked potential (PRVEP) and the visual acuity at particular visual angles. Methods Two hundred and ten volunteers were divided into seven groups, according to visual acuity as assessed by the standard logarithmic visual acuity chart (SLD-ii). For each group, the PRVEP components were elicited in response to visual angle presentations at 8°, 4°, 2°, 1°/60´, 30´, 15´, and 7.5´, in the whiteblack chess-board reversal mode with a contrast level of 100% at a frequency of 2 Hz. Visual stimuli were presented monocularly, and 200 presentations were averaged for each block of trials. The early and stable component P1 was recorded at the mid-line of the occipital region (oz) and analyzed with SPSS 13.00. Results (1) oz had the maximum P1 amplitude; there was no significant difference between genders or for interocular comparison in normal controls and subjects with optic myopia. (2) The P1 latency decreased slowly below 30´, then increased rapidly. The P1 amplitude initially increased with check size, and was maximal at ~1° and ~30´. (3) The P1 latency in the group with visual acuity ≤0.2 was significantly different at 8°, 15´ and 7.5´, while the amplitude differed at all visual angles, compared with the group with normal vision. Differences in P1 for the groups with 0.5 and 0.6 acuity were only present at visual angles <1°. (4) Regression analysis showed that the P1 latency and amplitude were associated with visual acuity over the full range of visual angles. There was a moderate correlation at visual angles <30´. Regression equations were calculated for the P1 components and visual acuity, based on visual angle. Conclusion (1) Visual angle should be taken into consideration when exploring the function of the visual pathway, especially visual acuity. A visual angle ~60´ might be appropriate when using PRVEP components to evaluate poor vision and to identify malingerers. (2) increased P1 amplitude and decreased P1 latency were associated with increasing visual acuity, and the P1 components displayed a linear correlation with visual acuity, especially in the range of optimal visual angles. Visual acuity can be deduced from P1 based on visual angle.

Post-mortem computed tomography (PMCT) and post-mortem computed tomography angiography (PMCTA) are rapidly becoming effective and practical methods in forensic medicine. In this article, we introduce a PMCTA approach by cardiac puncture and its application in a specific forensic case. A 50-year-old female sanitation worker was found dead on a road. External examination of the body revealed scattered abrasions and contusions over the chest. Autopsy was refused by the family members, and the body was examined with PMCT and PMCTA by cardiac puncture. Sternal fracture and rib fractures were detected by PMCT and aortic rupture by PMCTA. The cause of death was hemorrhagic shock due to traumatic aortic rupture. In certain circumstances, the combination of PMCT and PMCTA is helpful for forensic pathologists to determine the cause of death in cases involving traumatic vascular injury.

Sunulançalışmada, Batı Anadolu'da yer alan Eskişehir ilindeki yıldırım çarpmasına bağlı ölümlerin insidansı ve bu olgulara ait demografik verilerin ve çözüm önerilerinin paylaşılması amaçlanmıştır.

Objective. To explore the potential effects of methanol and its metabolite, formic acid, on rat retina function. Methods. Sprague-Dawley rats were divided into 3- and 7-day groups and a control. Experimental groups were given methanol and the control group were provided saline by gavage. Retinal function of each group was assessed by electroretinogram. Concentrations of methanol and formic acid were detected by GC/HS and HPLC, respectively. Results. The a and b amplitudes of methanol treated groups decreased and latent periods delayed in scotopic and photopic ERG recordings. The summed amplitudes of oscillatory potentials (OPs) of groups B and C decreased and the elapsed time delayed. The amplitudes of OS1, OS3, OS4, and OS5 of group B and OS3, OS4, and OS5 of group C decreased compared with the control group. The IPI1 of group B and IPI1-4 of group C were broader compared with the control group and the IPI1-4 and ET of group B were broader than group C. Conclusions. Both of scotopic and photopic retinal functions were impaired by methanol poisoning, and impairment was more serious in the 7-day than in the 3-day group. OPs, especially later OPs and IPI2, were more sensitive to methanol intoxication than other eletroretinogram subcomponents.