Assessment of depth perception using psychophysical thresholds and stereoscopically evoked brain activity

Dynamic random-dot stereograms (dRDS) elicit brain activity generated exclusively by cortical neurons sensitive to binocular horizontal disparity. We studied 20 adults with stereovision deficiency but otherwise normal vision. Psychophysical thresholds were determined with static RDS and with the three-rod experiment. VEP was recorded from seven occipital channels. Stimuli were presented on a monitor by dRDS as stereoscopic checkerboard patterns that moved in depth with 8 depth reversals per second. Horizontal disparity ranged from 7 to 24.5 min of arc. Stimuli were displayed at the center, or in the left or right half field. We determined electrophysiological thresholds as well as the disparity where largest responses occurred. Subjective and electrophysiological thresholds showed a significant positive correlation. In addition, the right visual field was more sensitive to dRDS stimuli than other locations. Squint angle was related to the disparity thresholds. Our data illustrate correlations between clinical symptoms, perceptual deficiency, and VEP parameters.     

Hemangiopericytoma of the Greater Omentum

A 41-year-old Chinese woman was admitted to our hospital with epigastric pain. Computed tomography detected a heterogeneous enhancement tumor fed by the left gastroepiploic artery in the left lower quadrant and cholelithiasis. Excision of the tumor in the greater omentum and cholecystectomy were performed laparoscopically. Histological findings confirmed a diagnosis of hemangiopericytoma with low-grade malignancy. To our knowledge, hemangiopericytoma of the greater omentum is very rare, and only 12 cases were reported in English literature. We report a case of hemangiopericytoma arising in the greater omentum and review the literature.     

True smooth muscle neoplasms of the gastrointestinal tract: morphological spectrum and classification in a series of 85 cases from a single institute

BACKGROUND AND AIM: True smooth-muscle neoplasms of the GI tract have been only rarely studied in the KIT era. Their incidence among other GI mesenchymal tumours and their clinicopathological spectrum have not been sufficiently analysed. MATERIALS AND METHODS: We reviewed all GI mesenchymal lesions at the Pathology Institute of the Nuremberg Clinic Centre from 1994 through 2005. RESULTS: Among 262 lesions, there were 142 GISTs (54%) and 85 true smooth muscle neoplasms (32%). Smooth muscle neoplasms comprised 72 polypoid leiomyomas (78%, 5 oesophageal and 67 colorectal), 10 intramural leiomyomas (11%, 5 oesophageal, 4 gastric and one ileal), two intramural leiomyosarcomas in the sigmoid colon and ileum (2%) and one polypoid leiomyosarcoma involving the stomach, descending colon and the retroperitoneum concurrently. None of the leiomyomas with available follow-up have recurred or metastasised. CONCLUSION: Smooth muscle neoplasms are the second most common mesenchymal neoplasms in the GI tract after GISTs. They may arise either from the muscularis mucosae or proper muscle layer forming polypoid and intramural lesions, respectively. Polypoid leiomyomas are more common in the rectosigmoid, while intramural ones mainly arise in the vicinity of the oesophagogastric junction. Polypoid leiomyomas are sufficiently treated by endoscopic resection, and local surgical excision is the treatment of choice for intramural leiomyomas. Intramural leiomyosarcomas are rare high-grade sarcomas that commonly have infiltrated into the surrounding tissue or metastasised by the time of diagnosis.     

Central serous chorioretinopathy and risk for obstructive sleep apnea

Patients with obstructive sleep apnea (OSA), in comparison to controls, have increased levels of circulating epinephrine and norepinephrine, both of which are risk factors for the development of central serous chorioretinopathy (CSCR). The aim of this pilot study was to investigate the frequency of symptoms that suggest OSA in CSCR patients and normal controls. The Berlin Questionnaire, a validated research tool to assess risk for OSA, was administered to 29 patients who met the criteria for active, acute, non-steroid-induced CSCR and 29 controls matched for age and sex. In this retrospective case-controlled study, the main outcome measure was increased risk for OSA. The mean age of the patients was 47.8 years (range 29–72) and the mean age of controls was 47.3 years (range 25–70). Seventy-six percent (22) of both groups were men. Survey scores showed 58.6% (17) of patients with CSCR to be at an increased risk for OSA compared to 31.0% (nine) of controls. A conditional logistic regression analysis showed that the CSCR group had a higher proportion with an increased risk for OSA compared to the control group (odds ratio=3.67; 95% CI: 1.02, 13.14; P = 0.046). Patients with CSCR may be more likely than other adults to have OSA, and screening for this sleep disorder should be considered in this population. Further research is warranted to determine whether sleep apnea may contribute to the development of CSCR, and to assess whether treatment of sleep apnea might offer a new therapeutic option for some patients with CSCR.     

Mapping the social and physical contexts of physical activity across adolescence using ecological momentary assessment

BACKGROUND: Research has sought to understand how environmental factors influence adolescent physical activity, yet little is known about where and with whom adolescents are physically active. PURPOSE: This study used electronic ecological momentary assessment (e.EMA) to map the social and physical contexts of exercise and walking across adolescence. Differences in physical activity contexts by gender, grade in school, day of the week, and season were examined. METHODS: Twice a year between 9th and 12th grade, 502 adolescents (51% female) of mixed ethnicity (55% White) participated in 4-day e.EMA intervals (Thursday-Sunday) where their primary activity (e.g., exercise, TV, homework), social company (e.g., friends, family, class), and physical location (e.g., home, school, outdoors) were assessed every 30 (+/-10) min during waking hours. RESULTS: Overall, greater proportions of exercise and walking were reported with friends, outdoors, and at school. However, boys were more likely to report exercising and walking in outdoor locations than girls. Exercising with classmates, family, and at school decreased across high school. Walking with family, friends, and outdoors also decreased. On weekdays compared to weekends, students reported a greater proportion of their exercise and walking at school. Students were more likely to report exercising and walking outdoors in the fall and the spring than in the winter. CONCLUSION: e.EMA showed that the social and physical contexts of adolescent exercise and walking vary as a function of gender, grade in school, day of the week, and season. Understanding the contexts of physical activity during the high school years can be helpful in designing interventions during adolescence.     

One-year follow-up results of combined use of CO<Subscript>2</Subscript> laser and cold instrumentation for Reinke’s edema surgery in professional voice users

The purpose of this study was to present our experience with combined use of CO₂ laser and cold instrumentation for Reinke’s edema surgery and to evaluate 1-year follow-up results of the technique in a series of professional voice users. Fifteen patients with Reinke’s edema who underwent microlaryngoscopic surgery were included. Videolaryngostroboscopy, perceptual and acoustic voice analyses were performed before and after surgery. During the 1-year follow-up, no recurrence of Reinke’s edema was encountered. Significant postoperative improvement was obtained in the quality of voice, in terms of GRBAS scores, Fo, jitter, shimmer and NHR. No evidence of laryngeal cancer was found on the histological examinations. Combined use of CO₂ laser and cold instrumentation provides a reliable and safe method for Reinke’s edema surgery, and cessation of smoking, voice rest and control of the laryngopharyngeal reflux contribute to the success of surgery. We consider that the removal of redundant mucosa of the vocal fold reduces the risk of the recurrence of Reinke’s edema and provides better quality of voice. However, it does not imply that our method is superior to others’, but this procedure constitutes an effective treatment of choice for Reinke’s edema patients, including professional voice users.     

Fixation instability and oculomotor abnormalities in Friedreich's ataxia

Eye movements were studied in 13 patients with Friedreich's ataxia and correlated with MRI findings to investigate whether oculomotor abnormalities can be traced to cerebellar disturbances in this disease. One of the most prominent eye signs was fixation instability (square-wave jerks, SWJ.). Besides SWJ the patients showed various combinations of cerebellar, vestibular and brain-stem oculomotor signs. Our patients did not comprise a homogeneous group with regard to their oculomotor findings. There was no correlation between the severity of any of the so-called cerebellar oculomotor disturbances and the number of SWJ. We tried to correlate the extent of oculomotor disturbances with floccular atrophy and atrophy of the dorsal vermis on MRI in seven of the patients. None of the oculomotor features (including SWJ) correlated with flocculus or dorsal vermis size. Furthermore, floccular and vermal measurements on MRI were normal. Accordingly, we think it unlikely that the oculomotor disturbances, including SWJ, are attributable to cerebellar pathology per se.     

Changes in EEG order in neuroleptically treated normal volunteers during a voluntary movement task

Summary 15 normal volunteers were treated over three weeks with haloperidol (HAL) and in the third week additionally with biperidene (BIP). The order of the EEG spectra at different topographical locations and in different frequency bands during a movement task was analyzed using uncertainty analysis (UA), a multivariate analysis technique based on informationtheoretical methods. Different patterns of drug-induced changes were found. HAL decreases the theta and alpha band order at the fronto-central lateral areas but increases it at the fronto-central midline in the theta band and at the parietal areas in the alpha band. With the exception of the fronto-central midline locations, BIP more or less counterbalances the effect of HAL. Volunteers felt unwell and had motor disturbances during HAL and felt well again during HAL + BIP. Reaction time values were increased during HAL and normalized during HAL + BIP.