Continued studies in cognitive function in problem solving of graded difficulty (1) has now proceeded through several thousand tests of high school students in a six weeks period last summer. The optical imager uses 9 sources and 23 detectors operated in time multiplex to give an image of the prefrontal region in several seconds. Thus, the image can be acquired in the state prior to activation, during and following activation. The images are acquired at two wavelengths, 750 and 850 nm, from which the changes of blood concentration (blood pooling) and relative oxygenation/deoxygenation state (metabolic activity) can be obtained and with suitable calibrations converted into micromolar changes of total Hb concentration and fractional changes of oxygenation, respectively. The imager has a flexible, wearable pad applied to the forehead and the electronics presents the running average of the two quantities mentioned above in the 16 voxels which cover the prefrontal region. The protocol involves a scanning through multi-letter anagrams of graded difficulty which include problems ellicitating maximal activation (>3 solutions in the 30 sec test interval) or are to easy, or too difficulty. Anagrams are presented in a sequence of three, four, five letter anagrams of to the maximal level of difficulty and back to the starting point. Each anagram is displayed for approximately one minute. Computer scanning of the results gives histograms of the several hundred tests per individual in the "training" interval (for three weeks) and in the post training interval (3 weeks). Usually two or three complete trials per day were achieved with the result that the group of 7 students produced over 2600 test results. The histogram displays were studied to determine a) the most fruitful voxels, b) the approximate of the total tests that appeared in those voxels and c) the maximum signal level observed in the histogram display in units of micromolar hemoglobin. The product these two was taken as the Figure of Merit and their displays of the 16 voxels gave patterns for trained and untrained responses. The preliminary conclusions of this study were: a) that the training effect was very large, pre-training exhibited a chaotic voxel distribution for all difficulty levels while trained students gave a higher output and activated only one or two of the 16 voxels. If the tests was too easy, too hard, i.e., an ability/difficulty mismatch, frustration or disattention gave similar chaotic patterns; b) a match between difficulty and ability activated only one or two voxels in similar locations for the group. Since attention and success measure appear to be of interest in school room studies, a wearable imager with local LCD display is being supplied to the Senior class of the local high school for those individuals who have already had last Summer's training in anagrams. It is concluded that wearable NIR measurements of metabolic activation and blood flow may be a useful educational aid.

Study designA prospective clinical study assessing new vertebral compression fracture after previous treatment.ObjectiveThe purpose of this study was to investigate the incidence and associated risk factors of new symptomatic osteoporotic vertebral compression fractures (OVCFs) in patients treated by percutaneous vertebroplasty (PVP) and kyphoplasty (PKP) versus conservative treatment, and to elucidate our findings.Summary of background dataThere are a lot of reports concerning the feasibility and efficacy of this minimally invasive procedure compared with conservative treatment, especially in pain soothing. However, it is still unclear whether the risk of subsequent fracture has increased among operative treatment patients in the long term.MethodsFrom November 2005 to July 2009, 290 consecutive patients with 363 OVCFs were randomly selected for PVP/PKP or conservative treatment and evaluated with a mean follow-up of 49.4 months (36–80 months). Some parameters were characterized and statistically compared in this study. Telephone questionnaires, clinical reexamine, and plain radiographs were performed in the follow-up.ResultsThirty-one of 290 (10.7 %) patients had experienced 42 newly developed symptomatic secondary OVCFs. Among 169 operation (53.3 % vertebroplasty, 46.7 % kyphoplasty) and 121 comparison patients, there is no significant statistical difference of new OVCFs incidence between the two groups calculated by patient proportion. However, in separate, the rate of secondary adjacent fractures calculated by vertebral refracture number is significantly higher than non-adjacent levels in PVP/PKP group but no significant statistical difference was observed in conservative group. The time interval of recompression after operative procedure was much shorter than that for comparison group (9.7 ± 17.8 versus 22.4 ± 7.99 months, p = 0.017). In addition, older age, gender, fracture times, location of original fracture segment, the amount of cement, cement leakage, operation modality (PVP or PKP),and initial number of OVCFs were documented, but these were not the influencing factors in this study (p > 0.05).Conclusions Patients who had experienced PVP/PKP were not associated with an increased risk of recompression in new levels. However, recompression in new levels of PVP/PKP group occurred much sooner than that of conservative group in the follow-up period. The incidence of new vertebral fractures observed at adjacent levels was substantially higher but no sooner than at distant levels in PVP/PKP group. No major risk factors involving new OVCFs have been found in this study and  augmentation for sandwich situation is not necessary.

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During exercise, the metabolic need for oxygen in muscles increases many times above the resting level. To meet this oxygen demand, oxygen supply to the contracting muscle must increase; this is accomplished by an increased cardiac output and a redistribution of the blood supply. During exercise, heteroJapanese Journal of Physiology Vol. 51, No. 5, 2001 599Japanese Journal of Physiology, 51, 599-606, 2001 Key words: near infrared light, imaging, oxygen saturation, blood volume, heterogeneity.Abstract: Using a near infrared (NIR) imaging device, we tested the hypothesis that regional differences in oxygen status could be detected in the gastrocnemius muscle during exercise and recovery. Six healthy subjects performed the standing plantar flexion exercises for 2 min; the frequency was one contraction per second. The NIR imaging device was placed over the medial head of the right gastrocnemius muscle and the signals from two optical sensors situated on the middle proximal and middle distal portions were used. The NIR-O 2 saturation (difference between deoxygenated and oxygenated Hb signals) and NIR-blood volume (sum of the oxygenated and deoxygenated Hb signals) were calculated in optical density units. Plantar flexion resulted in more deoxygenation during exercise and more reoxygenation during recovery in the distal portion compared with the proximal portion. The changes in NIR-O 2 between rest and a 2 min exercise, and between a 2 min exercise and a 3 min recovery were 0.11 and Ϫ0.23, respectively, in the distal portion, which were significantly larger than proximal values (0.05 and Ϫ0.10, pϽ0.05). Plantar flexion resulted in lower NIR-blood volumes during exercise and greater recovery of blood after exercise in the distal portion compared with the proximal portion. The changes in NIR blood volume between rest and a 2 min exercise and between a 2 min exercise and a 3 min recovery were Ϫ0.19 and 0.31, respectively, in the distal portion, significantly larger than proximal values (Ϫ0.07 and 0.12, pϽ0.05 for all comparisons). These findings indicate that the distal portion of the medial gastrocnemius had larger changes in NIR-O 2 saturation and NIR-blood volume than the proximal portion had. This is consistent with the distal portion having a greater impairment of blood flow possibly because of the higher intramuscular pressure during exercise. In conclusion: (1) regional differences in oxygen status in the gastrocnemius muscle were detected with exercise, with the distal portion having greater NIR-O 2 saturation and NIR-blood volume changes, and (2) the NIR imaging device might be a useful method to detect the regional differences of oxygen status in the muscle.

Children developed retinoblastoma at a young age. Early diagnosis is difficult. Key factors of clinical treatment and long survival rate were diagnosis and treatment at the early stage with multidisciplinary methods.