Value of 100 kVp scan with sinogram-affirmed iterative reconstruction algorithm on a single-source CT system during whole-body CT for radiation and contrast medium dose reduction: an intra-individual feasibility study.

AIM: To perform an intra-individual investigation of the usefulness of a contrast medium (CM) and radiation dose-reduction protocol using single-source computed tomography (CT) combined with 100 kVp and sinogram-affirmed iterative reconstruction (SAFIRE) for whole-body CT (WBCT; chest-abdomen-pelvis CT) in oncology patients. MATERIALS AND METHODS: Forty-three oncology patients who had undergone WBCT under both 120 and 100 kVp protocols at different time points (mean interscan intervals: 98 days) were included retrospectively. The CM doses for the 120 and 100 kVp protocols were 600 and 480 mg iodine/kg, respectively; 120 kVp images were reconstructed with filtered back-projection (FBP), whereas 100 kVp images were reconstructed with FBP (100 kVp-F) and the SAFIRE (100 kVp-S). The size-specific dose estimate (SSDE), iodine load and image quality of each protocol were compared. RESULTS: The SSDE and iodine load of 100 kVp protocol were 34% and 21%, respectively, lower than of 120 kVp protocol (SSDE: 10.6±1.1 versus 16.1±1.8 mGy; iodine load: 24.8±4versus 31.5±5.5 g iodine, p<0.01). Contrast enhancement, objective image noise, contrast-to-noise-ratio, and visual score of 100 kVp-S were similar to or better than of 120 kVp protocol. CONCLUSION: Compared with the 120 kVp protocol, the combined use of 100 kVp and SAFIRE in WBCT for oncology assessment with an SSCT facilitated substantial reduction in the CM and radiation dose while maintaining image quality.

California Dentists' Engagement in Media Advocacy for Sugar Restriction Policies.

OBJECTIVES: Increasing dentists' visibility in the media to make the case for sugary beverage taxes can help advance public policy that improves oral health outcomes. We assessed California dentists' media engagement behaviors related to sugar restriction policies for dental caries prevention and correlates of engaging in such behavior. METHODS: Survey items related to sugar policies and media engagement were embedded in an electronically distributed statewide survey of dentists' tobacco cessation counseling behaviors. Descriptive statistics were calculated for respondent characteristics, perceived professional responsibility to discuss selected topics with patients, and attitudes and behaviors related to sugar restriction policy and media communication. Multivariable models identified independent correlates of media engagement. RESULTS: Of 624 respondents, most had never talked to traditional media (78%) or posted to social media (64%) about sugar or sugar policies for dental caries prevention. Respondents with the highest level of media engagement were more likely to agree that sugary beverage taxes are effective at reducing dental caries, that they had support from dental professional organizations to talk to the media, that it is realistic for patients to reduce their sugar consumption, and that sugar and sugary drinks are extremely harmful to health. CONCLUSIONS: Efforts to increase dentists' media engagement related to sugar restriction policies for dental caries prevention should address dentists' negative attitudes toward the effectiveness of sugar restriction policies and may require increased support from dental professional societies. KNOWLEDGE TRANSFER STATEMENT: Study findings identify dentists' low engagement in media advocacy to support sugar restriction policy adoption. The results identify correlates of media engagement and of dentists' willingness and confidence to act, which could serve to inform interventions to support and enhance engagement.

Dental Professionals' Engagement in Tobacco, Electronic Cigarette, and Cannabis Patient Counseling.

OBJECTIVES: California features low smoking prevalence, cautionary electronic cigarette (e-cigarette) public messaging, and legal recreational cannabis: a unique landscape for dental professionals to navigate tobacco cessation promotion. This cross-sectional study assessed California dental professionals' self-reported tobacco patient counseling behaviors and the correlates of providing such assistance. METHODS: Statewide surveys of dental hygienists (n = 701) and dentists (n = 725) were distributed electronically. The dentist survey was weighted for sampling and nonresponse. Prevalence of asking patients about use was compared for cigarette and noncigarette products (e.g., e-cigarettes, cannabis). Multivariable models identified independent correlates of providing cessation assistance to tobacco-using patients. RESULTS: Respondents reported frequently (often/always) documenting patient tobacco use (hygienists: 80%; dentists: 73%) but less commonly provided forms of assistance (hygienists: 27%-49%; dentists: 10%-31%). Most respondents asked patients about cigarette smoking, but noncigarette product use (cigar, hookah, pipe, e-cigarette, or cannabis) was not commonly assessed. Greater confidence and willingness to assist were positively associated with providing assistance in multivariable models, but perceived barriers (e.g., lack of time and remuneration) were not. Results were robust to model specifications. CONCLUSIONS: California dental professionals often ask about smoking but lag in providing cessation assistance and inquiring about noncigarette products. Successful efforts to encourage dental professionals' engagement in tobacco prevention and cessation must enhance providers' self-efficacy and motivation and likely will require system and organizational change. KNOWLEDGE TRANSFER STATEMENT: Study findings identify substantial gaps in dental professionals' engagement in patient tobacco cessation. The results identify correlates of providing assistance and of dental professionals' willingness and confidence to do so, which could serve to inform interventions to support and enhance engagement.

Significance of Tei-index alterations induced by acute preload reduction with hemodialysis.

AIM: The load dependence of Tei-index, an index to estimate combined systolic and diastolic ventricular functions, remains controversial. Moreover, its significance in the setting of acute preload reduction including hemodialysis (HD) remains unknown. Therefore, we examined the significance of the Tei-index in HD patients. PATIENTS AND METHODS: Doppler echocardiographic parameters of 42 patients with normal left ventricular ejection fraction (LVEF) were evaluated before and after HD. Based on the index of body water excess calculated using a Crit-Line monitor, the patients were assigned to Group A (normal hydration approximately overhydration) and Group B (risk of pulmonary congestion). RESULTS: Group A was younger and had a shorter isovolumic relaxation time (IRT) than Group B before HD. Hemodialysis significantly increased the Tei-index of Group A, which was derived from prolonging IRT and isovolumic contraction time and shortening the ejection time without changing LVEF. Changes in the Tei-index (DeltaTei-index) significantly correlated with the rate at which blood volume decreased. They were derived from graphs generated using the Crit-Line monitor. Furthermore, the DeltaTei-index inversely correlated with the Tei-index before HD. CONCLUSION: These findings suggest that the Tei-index is preload-dependent, which is related to changes in volume and speed. Thus, the Tei-index should be cautiously interpreted according to various hemodynamic situations. However, the correlation between the DeltaTei-index and the Tei-index before HD implies that the latter could be a good indicator of effective fluid removal by HD.

Creutzfeldt-Jakob disease associated with cadaveric dura mater grafts in Japan.

A nationwide survey and recent information documented 57 patients with Creutzfeldt-Jakob disease (CJD) who had received dura mater grafts during the period between January 1979 and September 1999. At least 54 of these 57 patients received the same brand of dura mater graft from the same processor. Mean age at disease onset in the 57 patients with dural grafts was younger (51.9 years) than that in patients with sporadic CJD (63 years) (p < 0. 0001). Initial symptoms were cerebellar ataxia, disorientation, and visual or oculomotor disturbance.

Incidence rate of Creutzfeldt-Jakob disease in Japan.

BACKGROUND: The objective of this study is to clarify the incidence rate of Creutzfeldt-Jakob disease (CJD) during the last decade in Japan. METHODS: A nationwide mail survey was conducted in all hospitals with a minimum bed capacity of 100 and having at least one of three departments: neurology, psychiatry, and neuropathology. The survey required the patient's sex, date of birth, date of diagnosis, diagnostic criteria, medical history and CJD incidence in the family. RESULTS: From 493 hospitals throughout the country, 821 patients with CJD were reported from January 1985 through March 1996. The annual incidence rate was 0.49 per million population for males and 0.68 for females. The age-specific incidence rate was highest among those 70-79 years of age, followed by the 60-69, and 50-59 age groups. The incidence and mortality increased during the observed period; however, the incidence rate among younger generations did not rise. CONCLUSION: A nationwide incidence survey of CJD in Japan revealed the incidence and distribution of the disease over the recent decade. It was found that the incidence and mortality rates had increased during the observed period.

Effects of a small dose of triazolam on P300 and resting EEG.

The aim of the present study was to clarify whether cognitive impairments caused by benzodiazepines (BDZs) are a consequence of their specific direct effects on cognitive function or whether they are explained as secondary effects of increased sleepiness. Ten healthy men (mean age, 33.9 years) participated in two experimental sessions in a randomized cross-over, double-blind study: in one session subjects were given a placebo and in the other they were given 0.125 mg triazolam (TRZ). Each experimental session was conducted on 1 day. After a pre-drug EEG recording and an event-related potential (ERP) recording, under an oddball paradigm, subjects took the TRZ or placebo orally at 1000 hours. Thereafter, EEG and ERP recording sessions, following the same procedure as the pre-drug sessions, were conducted at 1, 2, 4, 6 and 8 h after drug administration. The EEG and ERP recordings from Cz and Pz referred to the bilaterally linked ear electrodes were used. We found that P300 latency was significantly prolonged in TRZ condition at 2 h (Pz) and 4 h (Cz and Pz) after TRZ, and that the P300 amplitude was significantly reduced at 2 h (Cz and Pz) and 4 h (Pz) after TRZ, compared to the same times after placebo. The absolute power values for the theta (4-7 Hz), alpha 1 (8-9 Hz), and alpha 2 (10-12 Hz) bands did not differ at any measurement time between the treatments. Only the beta band (13-19 Hz) power value was significantly elevated after the TRZ administration (versus placebo). No significant sedative effects were detected in subjective measurements. These results indicate that a single oral dose of 0.125 mg TRZ caused cortical changes without distinct general sedation or subjective sleepiness.

Altered phase relation between sleep timing and core body temperature rhythm in delayed sleep phase syndrome and non-24-hour sleep-wake syndrome in humans.

Changes in the phase relation between sleep timing and the circadian pacemaker are suspected to have an etiological significance in circadian rhythm sleep disorders. Simultaneous recordings of rest-activity and rectal temperature in seven sighted delayed sleep phase syndrome (DSPS) patients, seven sighted non-24-h sleep-wake syndrome (non-24) patients, and 14 healthy controls were made for 10-14 days continuously in the subjects' homes. We found that sleep length and the interval from the body temperature (BT) trough to sleep offset were significantly longer in both non-24 and DSPS patients than in the controls, and that the interval between sleep onset and the BT trough was significantly less in the non-24 patients than in the DSPS patients and the controls. We postulate these alterations in phase relation to be associated with phase changes of the circadian pacemaker via different illumination timings.

Transjugular intrahepatic portosystemic shunt: initial clinical experience and three-year follow-up.

To define the role of transjugular intrahepatic portosystemic shunt (TIPS), we prospectively studied 12 patients undergoing this procedure for variceal bleeding, refractory ascites, and hemorrhagic gastropathy due to portal hypertension. The TIPS creation was successful in 11 patients, and portal pressure immediately decreased an average of 8.3 cm H2O. Esophageal varices improved in six of seven patients, but gastric varices with spleno- or gastro-renal shunt did not change in three of four patients. A hemorrhage from portal hypertensive gastropathy was controlled immediately. Ascites improved in all six patients. Hepatic encephalopathy newly developed in four patients, but was controllable with medical treatment. During the follow-up period (mean, 25 months), shunt dysfunction was evident in eight of 10 patients. Stenosis and occlusion of the shunt were successfully treated by redilatation and/or placement of an additional stent. The cumulative survival rate was 73% at one year and 64% at two years. These results suggest that TIPS is a safe and effective treatment for uncontrollable complications due to portal hypertension, but is not effective for gastric varices with spleno- or gastro-renal shunt. Careful follow-up and shunt revision are necessary for the maintenance of shunt patency.

Metastatic liver tumor from cystic ovarian carcinomas: CT and MRI appearance.

OBJECTIVE: The initial and follow-up CT and MRI images of ten patients with hepatic metastases from ovarian tumors were retrospectively analyzed to establish their features and sequential changes in appearance. MATERIALS AND METHODS: Ten patients with hepatic metastasis from ovarian tumors received initial and follow-up CT and MRI examinations. Six patients were followed up every two to three weeks before surgical tumor resection. Both CT and MR images were analyzed by two radiologists. RESULTS: A total of fourteen lesions were detected by CT and MRI in 10 patients. All 14 lesions were demonstrated as areas of marked hyperintensity on T2-weighted MRI. Eleven cyst-like tumors were demonstrated as round or oval low density lesions on CT and as areas of hypointensity on T1-weighted imaging. Three lesions were shown as solid masses with slightly low attenuation at the initial CT examination and slightly low or iso-intensity areas on T1-weighted imaging, and these lesions showed early peripheral globular enhancement and delayed enhancement on contrast-enhanced CT and MR imaging. Cystic formation was observed two to three weeks later after initial study in all the 3 solid lesions. Rapid subcapsular effusion, which showed obvious enhancement on delayed Gd-DTPA enhanced MR imaging, was observed in two patients. CONCLUSION: The hepatic metastatic tumor from cystic ovarian carcinoma may manifest as a well-defined cystic lesion or as a solid mass, and the solid mass shows delayed enhancement on contrast-enhanced CT and MR imaging. Furthermore, rapid cystic formation and rapid subcapsular extension is frequently seen.

Small cell carcinoma of the stomach: a case report.

A case of a gastric small cell carcinoma discovered incidentally by screening ultrasonography is presented. Ultrasonography demonstrated a subcardial metastatic lymph node and multiple hepatic metastatic lesions. Upper GI series and gastroendoscopy revealed a large ulcerated tumor in the cardia of the stomach, and a Borrmann type II tumor, 4 x 2.5 cm, was found in the resected stomach. We describe the radiological findings of the upper GI series, ultrasonography, CT, and gastroendoscopy, and review the literature.

Familial multiple trichoepithelioma associated with subclavian-pulmonary collateral vessels and cerebral aneurysm--case report.

A 63-year-old woman presented with cerebellar infarction caused by occlusion of the right posterior inferior cerebellar artery. She had papules on her face that were identified histologically as multiple trichoepithelioma. Angiography revealed right subclavian-pulmonary collateral vessels and a cerebral aneurysm arising from the bifurcation of the right middle cerebral artery. Her grandmother, mother, and uncle had had similar papules, and the deaths of her mother and uncle were due to subarachnoid hemorrhage.

[Reduction of the influence of the liver uptake to the myocardial uptake on technetium-99m myocardial SPECT; usefulness and problems of a mask processing method].

The aim of this study is to evaluate the usefulness of a mask processing method for obtaining the true myocardial tracer distribution by eliminating the influence of the liver uptake to the myocardial uptake on myocardial SPECT images by using technetium-99m (99mTc) blood flow agents. A SPECT imaging was performed with a two-head SPECT system (GCA-7200A/DI) in both phantom and clinical studies. The mask processing method was applied to the reconstructed and projection images. The phantom consisted of heart, lung, liver and spine. A defect was located in the inferior wall of the left ventricle and other parts of the heart and liver were filled with 99mTc solution. For clinical study 10 patients with difficulty in the interpretation of the inferior wall were selected for the evaluation of usefulness of the mask method. In the phantom study, the mask processing method applied to the reconstructed images was able to remove the overlapped liver from the heart, but was not able to remove the influence of the liver uptake to the myocardial uptake. Nevertheless, the mask processing method applied to the projection images successfully eliminated not only the overlapped liver but also the influence of the liver uptake to the myocardial uptake. In the clinical study, the liver uptake could be removed from the uptake in the inferior wall in 8 of 10 patients with the mask processing methods. In 2 patients, the overlapped liver uptake could not be eliminated from the uptake in the inferior wall because the distance between the liver and heart was too short. The mask processing method applied to the projection images was thought to be superior to that applied to the reconstruction images in both phantom and clinical studies. The mask processing method, especially applied to the projection images, seems to be useful for the elimination of the liver uptake from the inferior wall of the myocardium on myocardial SPECT images using 99mTc blood flow agents.

[Technical investigation of cerebral blood flow measurements using the Patlak Plot method--a contrivance for positioning of the gamma camera at data collection in radionuclide angiography].

The time-activity curve for the aortic arch obtained from radionuclide angiography (RNA) is handled as an input function parameter according to the method of Matsuda et al., which determines regional cerebral blood flow non-invasively. The data are collected from a frontal view of the thorax captured by RNA by their method, however we encountered a case in which it was difficult to identify aortic arch in the data collection from the frontal view. The precise identification of the aortic arch was implemented when the RNA data were collected from the left anterior oblique view of the thorax. No significant difference was noted in the measured values between the data collection from the frontal view and from the left anterior oblique view. Our method seems to be useful modification of the Patlak plot method.

[Evaluation of time dependency of the acetazolamide effect on cerebral hemodynamics as measured by 99mTc-ECD single-photon emission computed tomography].

PURPOSE: Kuwabara et al. have examined the cerebral artery dilation with acetazolamide (ACZ) challenge test using PET. And, they reported that ACZ reaction came out time dependently. We have developed a unique SPECT's method using Technetium-99m ethyl cysteinate dimer (99mTc-ECD) to verify the results obtained by Kuwabara et al. METHOD: 1000 MBq of 99mTc-ECD was exactly divided into three syringes. Each of which was intravenous infused (i.v.) at rest, 7.5, and 20 minutes after ACZ administration. Data collection was started using dynamic SPECT immediately after 99mTc-ECD i.v. at rest. Using necessary data only, SPECT images representing each of the three 99mTc-ECD i.v. was reconstructed. SPECT counts were obtained by the ROI method from each images to calculate relative CBF from rest to 7.5 and 20 minutes after ACZ administration. RESULT: The 18 hemispheres of nine patients in the negative control group in whom ACZ was not loaded. CBF was stable during the three evaluation. The measurement error our method was estimated as small. The 18 hemispheres of nine patients in the positive control group who has normal vasodilatory reserve, CBF was increased by 26.2 +/- 8.1% at 7.5 minutes and 29.3 +/- 13.1% at 20 minutes after ACZ administration. Seven patients with and chronic stage unilateral internal carotid artery severe stenosis and/or occlusion were evaluated as the test group. Case of unaffected side, CBF was increased by 17.6 +/- 6.9% at 7.5 minutes and 24.8 +/- 11.3% 20 minutes after ACZ administration. And, increase rate of CBF in the affected side was 2.8 +/- 1.6% at 7.5 minutes and 17.3 +/- 5.0% at 20 minutes after ACZ administration. In the affected side, timing of the maximum CBF increase caused by ACZ was remarkably delayed. CONCLUSION: Our method based on 99mTc-ECD SPECT also revealed delayed cerebral artery dilation in the affected side. It was suggested that ACZ reaction came out time dependently, as reported by Kuwabara et al.

[Interpeak components of event-related potentials--comparison between normal and schizophrenic groups].

Event-related potentials (ERPs) during a two-tone discrimination task were recorded in 85 normal subjects and 110 schizophrenic subjects. We divided ERPs into 4 interpeak components. We named them A, A', B and B'. A is the component from the stimulus point to n100 peak. A' is the one from n100 peak to p200 peak. B is the one from p200 peak to n200 peak. B' is the one from n200 peak to p300 peak. Their latency was named Al, A'l, Bl, and B'l respectively. Their amplitude was also named Aa, A'a, Ba and B'a respectively. Bl and A'l of the schizophrenic group were both significantly longer than those of the normal group. B'a of the schizophrenic group was significantly smaller than that of the normal group. Interrelations between interpeak components of the normal group were examined statistically. Regarding latency, a significant negative correlation was seen between Al and A'l, and also between Bl and B'l. Regarding amplitude, a significant positive one was seen between Aa and A'a, and also between Ba and B'a. Interrelations between Al and A'l, Bl and B'l, Aa and A'a, and Ba and B'a of the schizophrenic group were the same as those of the normal group. These negative correlations in latency suggest that n100 peaks and n200 peaks have 'jitter'. A combination of interpeak components is supposed to reflect a higher function of the brain. There was a significant negative correlation between (A + A')l and (B + B')l in the normal group, but there was not a significant one between them in the schizophrenic group. The schizophrenic group is supposed to have a certain abnormality in a higher function of the brain. Our result suggests that we may possibly be able to associate an abnormal focus around p200 peak with some symptoms and signs of schizophrenia.

[Mechanism of attention in sleep--the changes of waveforms of event-related potentials in sleep].

Since attention has such a close correlation with arousal level, the influence of sleep on the waveforms of event related potential (= ERP) must be studied in advance for evaluating attentiveness of human mental activity. ERP, which odd-ball paradigm was used to elicit, was examined in 9 adult and healthy subjects from arousal to sleep. And ERP during a whole night was also examined in 5 of them to study the relation of the waveforms of ERP and sleep stages including a stage of rapid eye movement. As a result, there were some clear differences between the waveforms of the rare and frequent stimuli, and with change of sleep stages the differences also changed. Remarkable increase of amplitude and prolongation of latency of P200 and N200 were found in the waves of target stimuli in stage I. Activities of both components were connected with each other like a complexed component and preceded by the change of P300 activities. The waveforms of target stimuli in stage II had same kind of components with those of arousal stage. There were increased P200, N200, P300 activities and subsequent large negative activity which we called N3. These components were not clear in the waveforms of non-target stimuli. But P300 and N3 components were disappeared gradually during stage III. The averaged waveforms in stage III accompanied with 14-16 Hz fast wave suggested that they were identical with K-complex of sleep EEG. Add to this result, the habituation usually observed on P200 and N200 of nontarget stimuli in arousal let us to think that they are also identical with orienting reflex by rare and novel stimuli of external events (Sokolov). According to the result of examination changing the probability of target stimuli (20%----50%----80%), the waves of target stimuli in stage II were dependent on the probability of rare stimuli as well as in arousal stage. The dependence on probability was thought to reflect an automatic processing of selecting stimuli by orienting reflex in sleep. Another 3 subjects were examined of auditory evoked response in sleep with the same stimuli and without a task of counting numbers of rare stimuli. In stage II, however, they showed the waveforms by rare stimuli just like those by rare and target stimuli of 9 subjects. Then, it was supposed that attentiveness for external stimuli might be existent in sleep and changeable with sleep stages.

Cavernous hemangioma of the liver: pathologic correlation with dynamic CT findings.

PURPOSE: To correlate the pathologic findings of cavernous hemangiomas with enhancement patterns seen at dynamic computed tomography (CT) performed after injection of contrast material. MATERIALS AND METHODS: Sixteen patients underwent dynamic CT followed by hepatectomy. Resected specimens of 16 cavernous hemangiomas, which ranged from 2 to 15 cm in diameter, were obtained. The average size of vascular spaces in the histologic specimen was correlated with their appearance on dynamic CT scans. RESULTS: In 11 tumors, characteristic progressive fill-in after peripheral contrast enhancement was seen (type 1). In type 1 tumors, three zones were noted within the tumor: areas of peripheral puddling in the arterial-dominant phase, areas of gradual fill-in, and areas of no or minimal enhancement. Vascular spaces in areas of peripheral global enhancement were significantly smaller than those in areas of gradual fill-in (P = .03). In areas of no or minimal enhancement, extensive scar tissue (n = 9) or cystic cavity (n = 3) was seen. In three hemangiomas smaller than 3 cm, enhancement occurred diffusely in the arterial-dominant phase and vascular space was small (type 2). In two tumors, enhancement was seen only in the periphery of the tumor (type 3), and the majority of tumor was occupied by the cystic cavity or scar tissue. CONCLUSION: Dynamic enhancement patterns of cavernous hemangiomas are related to the collective size of their constituent vascular spaces.