Evaluation of Incidental Findings on Abdominopelvic CT: Potential Benefit of Photon-counting Detector CT Over Conventional Single-energy CT.

PURPOSE: To assese of potential benefint of photon-counting detector CT (PCD-CT) over conventional single-energy CT (CSE-CT) on accurate diagnosis of incidental findings with high clinical significance (IFHCS). MATERIALS AND METHODS: This retrospective study included 365 patients who initially underwent abdominopelvic contrast-enhanced CT (AP-CECT) without non-enhancement (PCD-CT: 187 and CSE-CT: 178). We selected IFHCS and evaluated their diagnosability using CE-CT alone. IFHCSs that could not be diagnosed with only CE-CT were evaluated using additional PCD-CT postprocessing techniques, including virtual non-contrast image, low keV image, and iodine map. A PCD-CT scanner (NAEOTOM Alpha, Siemens Healthineer, Erlangen, Germany) was used. RESULTS: Thirty-nine IFHCSs (PCD-CT: 22 and CSE-CT: 17) were determined in this study. Seven IFHCSs in each group were able to diagnose with only CE-CT. Fifteen IFHCSs were able to diagnose using the additional PCD-CT postprocessing technique, which was useful for detecting and accurately diagnosing 68.2% (15/22) of lesions and 65% (13/20) of patients. All IFHCSs were accurately diagonosed with PCD-CT. CONCLUSION: PCD-CT was useful for characterizing IFHCSs that are indeterminate at CSE-CT. PCD-CT offered potential benefit of PCD-CT over conventional single-energy CT on evaluation of IFHCS on only abdominopelvic CT.

Reducing contrast dose using virtual monoenergetic imaging for aortic CTA.

Three-dimensional computed tomographic angiography (3D-CTA) is widely used to evaluate the inner diameters of vessels and the anatomical vascular structure prior to endoscopic aortic surgery or transcatheter valve implantation. Virtual monoenergetic imaging (VMI) is a new application in dual-energy CT (DECT). We evaluated the potential for contrast dose reduction in preoperative aortic CTA using VMI. To evaluate performance in terms of image quality and vessel shape, we quantified the contrast-to-noise ratio (CNR) and the vessel diameter using a cylinder phantom we developed, and used volume rendering to assess visual quality. All VMI had improved CNR values compared with conventional 120 kVp images at an iodine content of 15 mgI/mL. In each image, a virtual mono-energy of 40 keV yielded the highest CNR value, and an iodine content of 9 mgI/mL was comparable to that of conventional images with an iodine content of 15 mgI/mL. The circularity indices (CI) of the vascular model at 15, 12, and 9 mgI/mL were similar to those of the reference condition using conventional voltages; however, CI was degraded at iodine contents of 6 and 3 mgI/mL with VMI. In the case of iodine content of 15 mgI/mL, VMI was superior, with conventional image by visual evaluation. In the cases of iodine contents of 12 and 9 mgI/mL, image quality was judged to be almost the same level when comparing 12 and 9 mgI/mL to conventional images. In the case of 6 and 3 mgI/mL, reference image using conventional technique was superior to that of VMI. We demonstrated in that decreasing contrast iodine content is possible using VMI with an energy of 40 keV for preoperative aortic 3D-CTA.

The Effects of Inboard Shoulder Belt and Lap Belt Loadings on Chest Deflection.

Chest injuries occur frequently in frontal collisions. During impact, tension in the lap belt is transferred to the inboard shoulder belt, which compresses the lower ribs of the occupant. In this research, inboard shoulder belt and lap belt geometries and forces were investigated to reduce chest deflection. First, the inboard shoulder belt geometry was changed by the lap/shoulder belt (L/S) junction for the rear seat occupant in sled tests using Hybrid III finite element simulation, sled tests and THOR simulation. As the L/S junction was closer to the ASIS (anterior superior iliac spine), chest deflection of the Hybrid III was smaller. The L/S junction around the ilium has the potential to reduce chest deflection without significant increase of head excursion. For THOR, although the chest deflection reduction effect due to closer L/S junction to the ASIS was observed, chest deflection was still substantially large since the lap belt overrode the ASIS. Second, measures to hook the ASIS of the THOR by the lap belt were examined. Sled tests at 30 and 50 km/h were conducted with THOR in the rear seat, and it was demonstrated that the outboard lap belt and buckle pretensioners improved the lap belt and ASIS interaction, and were also useful in reducing the deflection at the inboard-side of the lower chest. Finally, the lap belt overlap with the ASIS was compared among 10 volunteers, Hybrid III, and THOR. Some volunteers had the ASIS located at the torso-thigh junction, and the lap belt did not overlap the ASIS sufficiently. However, although the ASIS location of THOR is also at the torso-thigh junction, the lap belt overlapped the ASIS because of the abdomen's and femur's shape. In the future, it will be necessary to consider that the outboard lap belt and buckle pretensioners are also effective for the ASIS restraint of all human car occupants.

Effectiveness of the Japanese DOLOPLUS-2: a pain assessment scale for patients with moderate-to-severe dementia.

BACKGROUND: This study aimed to assess whether the Japanese DOLOPLUS-2 scale could effectively identify pain in elderly individuals with moderate-to-severe dementia. METHODS: This study used a pre-test/post-test design with purposive sampling to select an experimental group and a historical control group. The inclusion criteria were a Functional Assessment Staging score of 5 or 6, a diagnosis of an orthopaedic disease that typically involves pain, the ability to say 'I am currently in pain' (to prevent medication errors), and a total DOLOPLUS-2 scale score ≥5 at the first pain assessment. In the experimental group (n = 19), each patient was assessed by the DOLOPLUS-2 scale at 2PM and 9PM each day for 5 days. If a patient's total score was ≥5, analgesics were prescribed and the patient was re-assessed approximately 3 hours later. In the control group (n = 20), data were collected from medical records over a 1-year period, and we matched the characteristics of the control group to that of the experimental group. We also reviewed nursing records to determine the number of times analgesics had been administered over the 5 days after the nurses had first recorded that the patient had experienced pain. RESULTS: Among the 19 patients in the experimental group, 15 received pain medication because of a total pain score ≥5. Before treatment, their mean DOLOPLUS-2 scale score was 7.5 ± 3.2, and their score significantly decreased to 2.9 ± 2.1 (P < 0.001) after treatment. The experimental group also received significantly more treatments with analgesic medication than the control group (χ(2) = 16.033, P < 0.001, φ = 0.641). CONCLUSION: This study's findings suggested that the Japanese DOLOPLUS-2 scale could adequately identify pain in elderly individuals with moderate-to-severe dementia.

Adult headform impact tests of three Japanese child bicycle helmets into a vehicle.

The head is the body region that most frequently incurs fatal and serious injuries of cyclists in collisions against vehicles. Many research studies investigated helmet effectiveness in preventing head injuries using accident data. In this study, the impact attenuation characteristics of three Japanese child bicycle helmets were examined experimentally in impact tests into a concrete surface and a vehicle. A pedestrian adult headform with and without a Japanese child bicycle helmet was dropped onto a concrete surface and then propelled into a vehicle at 35 km/h in various locations such as the bonnet, roof header, windshield and A-pillar. Accelerations were measured and head injury criterion (HIC) calculated. In the drop tests using the adult headform onto a concrete surface from the height of 1.5m, the HIC for a headform without a child helmet was 6325, and was reduced by around 80% when a child helmet was fitted to the headform. In the impact tests, where the headform was fired into the vehicle at 35 km/h at various locations on a car, the computed acceleration based HIC varied depending on the vehicle impact locations. The HIC was reduced by 10-38% for impacts headforms with a child helmet when the impact was onto a bonnet-top and roof header although the HIC was already less than 1000 in impacts with the headform without a child helmet. Similarly, for impacts into the windshield (where a cyclist's head is most frequently impacted), the HIC using the adult headform without a child helmet was 122; whereas when the adult headform was used with a child helmet, a higher HIC value of more than 850 was recorded. But again, the HIC values are below 1000. In impacts into the A-pillar, the HIC was 4816 for a headform without a child helmet and was reduced by 18-38% for a headform with a child helmet depending on the type of Japanese child helmet used. The tests demonstrated that Japanese child helmets are effective in reducing accelerations and HIC in a drop test using an adult headform onto a relatively rigid hard surface, i.e., simulating a road surface or concrete path. However, when the impact tests are into softer surfaces, the child helmet's capacity to decrease accelerations is accordingly reduced. Impacts into the windshield, while below the critical HIC value of 1000, indicated higher HIC values for a headform with a child helmet compared to an adult headform without a child helmet. The unpredictable nature of the results indicates further research work is required to assess how representative the stiffness of an adult headform is when compared to an actual head.

Head impact mechanisms of a child occupant seated in a child restraint system as determined by impact testing.

In side collision accidents, the head is the most frequently injured body region for child occupants seated in a child restraint system (CRS). Accident analyses show that a child's head can move out of the CRS shell, make hard contact with the vehicle interior, and thus sustain serious injuries. In order to improve child head protection in side collisions, it is necessary to understand the injury mechanism of a child in the CRS whose head makes contact with the vehicle interior. In this research, an SUV-to-car oblique side crash test was conducted to reconstruct such head contacts. A Q3s child dummy was seated in a CRS in the rear seat of the target car. The Q3s child dummy's head moved out beyond the CRS side wing, moved laterally, and made contact with the side window glass and the doorsill. It was demonstrated that the hard head contact, which produced a high HIC value, could occur in side collisions. A series of sled tests was carried out to reproduce the dummy kinematic behavior observed in the SUV-to-car crash test, and the sled test conditions such as sled angle, ECE seat slant angle and velocity-time history that duplicated the kinematic behavior were determined. A parametric study also was conducted with the sled tests; and it was found that the impact angle, harness slack, chest clip, and the CRS side wing shape affected the torso motion and head contact with the vehicle interior.

Progressive supranuclear palsy combined with Alzheimer's disease: a clinicopathological study of two autopsy cases.

We present here the clinicopathological characteristics of two autopsy-confirmed cases comorbid of progressive supranuclear palsy (PSP) and Alzheimer's disease (AD). Histopathologically, the amount and distribution of neurofibrillary tangles (NFTs) in the basal ganglia and brainstem fulfilled the pathological criteria of PSP proposed by the National Institute of Neurological Disorders and Stroke--The Society for PSP (NINDS-SPSP). The Braak stages of senile plaques and NFTs were stage C and stage V in Case 1, and stage C and stage IV in Case 2. These neuropathological findings confirmed that the two patients had combined PSP with AD. Our patients presented clinically with executive dysfunction prior to memory disturbance as an early symptom. Not only neurological symptoms such as gait disturbance, supranuclear ophthalmoplegia and pseudobulbar palsy, but emotional and personality changes and delirium were prominent. Therefore, symptoms of subcortical dementia of PSP were more predominant than AD-related symptoms in the present two patients. Comorbid PSP and AD further complicates the clinical picture and makes clinical diagnosis even more difficult.

Effects of hypoxia and hypoxic training on 8-hydroxydeoxyguanosine and glutathione levels in the liver.

The effects of hypoxia and hypoxic training on 8-hydroxydeoxyguanosine (8-OHdG), reduced glutathione (GSH), and oxidized glutathione (GSSG) levels and on glutathione reductase (GR) activity in the liver of rats were evaluated. Rats were divided into 3 groups: a hypoxia and exercise (HE) group, a hypoxia and sedentary (HS) group, and a normoxia and sedentary (NS) group. The liver 8-OHdG levels were lower in the HE and HS groups compared with the NS group (P <.05). No significant difference between in the liver 8-OHdG levels in the HE and HS groups were found. However, the liver GSH level in the HS group was lower than that in the NS group (P <.05), and the HE group had significantly higher levels of liver GSH than the HS group (P <.01). The activity of liver GR in the HS group was lower than that of the NS group (P <.05). Moreover, the liver GR activity of the HE group was significantly higher than that of the HS group (P <.01). No significant difference in liver GR activity between the HE and NS groups was noted. In conclusion, the present study confirmed that moderate hypoxia and hypoxic training attenuated liver DNA damage and decreased liver GSH levels and GR activity. These results indicate that moderate hypoxia and hypoxic training result in decreased oxidative stress.