Neuropsychological findings and psychiatric symptoms in HIV-1 infected and noninfected drug users.

Reports available on the extent and incidence of cognitive deficits in human immunodeficiency virus (HIV-1) patients are variable. To assess the influence of drug abuse and psychiatric symptoms on the extent of the cognitive deficit, we examined 42 drug-addicted HIV-1 patients and compared them with a group of seronegative drug addicts (n = 31) as well as with a group of healthy controls (n = 50), using a psychometric test battery and standardized psychiatric scales. We found no significant difference in the extent and incidence of cognitive deficits in the group of HIV-1 patients as compared with the seronegative drug addicts. Both groups, however, differed from the normal population group. Remarkable depressive symptoms were found in the HIV-1 infected patient group. We assume that long-term drug abuse contributes markedly to the cognitive deficit of HIV-1 patients, which is further influenced by depressive symptoms.     

Entwicklung eines Tibiamarknagels auf der Basis anatomischer Untersuchungen der intraossären Gefäße

The design of the tibial medullary nail can be improved in order to preserve intraosseus vessels by osteosynthesis of the tibia. The nutrient artery of the human tibia enters the compacta in an average height of 33% dorsally and is leaving it in a height of 50% of the tibial length. In the medullary cavity the vessel splits up. The main branch continues the distal course on the dorsal/dorsolateral side of the medullary cavity (endosteal). In the distal diaphysis this endosteal vessel is of great importance, since the periosteal blood supply in this region with high incidence of pseudarthrosis is guaranteed only by branches of the anterior tibial artery. Using a new unreamed tibial nail, which is flattened dorsally, it is possible to preserve the endostal main artery of the tibia.     

The combination of radiotherapy, adjuvant chemotherapy (cyclophosphamide-doxorubicin-ftorafur) and tamoxifen in stage II breast cancer. Long-term follow-up results of a randomised trial.

Two hundred patients with node positive stage II breast cancer were randomised to four groups after radical mastectomy and axillary evacuation: (1) Postoperative radiotherapy, (2) Adjuvant chemotherapy with eight courses of CAFt (cyclophosphamide 500 mg m-2 + doxorubicin 40 mg/m-2 + ftorafur 20 mg kg-1 orally day 1-14) every fourth week, (3) Postoperative radiotherapy and adjuvant chemotherapy and (4) postoperative radiation, adjuvant chemotherapy and tamoxifen 40 mg daily for 2 years. Thirty-two per cent of the patients discontinued treatment due to GI-toxicity, while 26% required dose reductions due to leukopenia. Radiation pneumonitis was more frequent after the combination of postoperative radiotherapy with chemotherapy. There was a better relapse-free survival in the groups receiving chemotherapy compared to radiotherapy alone (P = 0.05), which was highly significant in a multivariate Cox analysis (P = 0.004). No significant survival differences were seen. Tamoxifen had no clear overall effect but there were better relapse-free (P = 0.04) and overall (P = 0.004) survival with tamoxifen in estrogen receptor positive patients, while estrogen receptor negative patients had a somewhat poorer survival (P = 0.07) after tamoxifen. Local control was better (NS) after the combination (93%) radiotherapy and chemotherapy compared to either treatment alone (76% with radiotherapy and 74% with chemotherapy at 5 years).     

Eight-channel transmit/receive body MRI coil at 3T.

Multichannel transmit magnetic resonance imaging (MR) systems have the potential to compensate for signal-intensity variations occurring at higher field strengths due to wave propagation effects in tissue. Methods such as RF shimming and local excitation in combination with parallel transmission can be applied to compensate for these effects. Moreover, parallel transmission can be applied to ease the excitation of arbitrarily shaped magnetization patterns. The implementation of these methods adds new requirements in terms of MRI hardware. This article describes the design of a decoupled eight-element transmit/receive body coil for 3T. The setup of the coil is explained, starting with standard single-channel resonators. Special focus is placed on the decoupling of the elements to obtain independent RF resonators. After a brief discussion of the underlying theory, the properties and limitations of the coil are outlined. Finally, the functionality and capabilities of the coil are demonstrated using RF measurements as well as MRI sequences.     

Aktuelles medizinrechtliches Schrifttum, Richtlinien und Empfehlungen

Ohne Zusammenfassung     

Computer-assisted LISS plate osteosynthesis of proximal tibia fractures: feasibility study and first clinical results.

Fluoroscopy is the most common tool for the intraoperative control of long-bone fracture reduction. Limitations of this technology include high radiation exposure for the patient and the surgical team, limited visual field, distorted images, and cumbersome verification of image updating. Fluoroscopy-based navigation systems partially address these limitations by allowing fluoroscopic images to be used for real-time surgical localization and instrument tracking. Existing fluoroscopy-based navigation systems are still limited as far as the virtual representation of true surgical reality is concerned. This article, for the first time, presents a reality-enhanced virtual fluoroscopy with radiation-free updates of in situ surgical fluoroscopic images to control metaphyseal fracture reduction. A virtual fluoroscopy is created using the projection properties of the fluoroscope; it allows the display of detailed three-dimensional (3D) geometric models of surgical tools and implants superimposed on the X-ray images. Starting from multiple registered fluoroscopy images, a virtual 3D cylinder model for each principal bone fragment is constructed. This spatial cylinder model not only supplies a 3D image of the fracture, but also allows effective fragment projection recovery from the fluoroscopic images and enables radiation-free updates of in situ surgical fluoroscopic images by non-linear interpolation and warping algorithms. Initial clinical experience was gained during four tibia fracture fixations that were treated by LISS (Less Invasive Stabilization System) osteosynthesis. In the cases operated on, after primary image acquisition, the image intensifier was replaced by the virtual reality system. In all cases, the procedure including fracture reduction and LISS osteosynthesis was performed entirely in virtual reality. A significant disadvantage was the unfamiliar operation of this prototype software and the need for an additional operator for the navigation system.     

Aktuelles medizinrechtliches Schrifttum, Richtlinien und Empfehlungen

Ohne Zusammenfassung     

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.     

Pericentral retinal dystrophy

A diagnosis of pericentral retinal dystrophy was made in 28 patients from four families, all living in North Norway. Patients from two and three generations were examined, establishing the relatively benign but progressive course of the disease. The advanced stage of pericentral retinal dystrophy could not be differentiated from the advanced stage of 'classical' retinitis pigmentosa. Three families demonstrated an autosomal dominant pattern of inheritance. In one family the mode of inheritance probably was autosomal recessive. Fluorescein angiography in the initial stage of the disease was normal, without evidence of pathological changes in the pigment epithelium or choroidal vessels, indicating that the pathological process may start in the photoreceptors.     

The inanimate environment of an intensive care unit as a potential source of nosocomial bacteria: evidence for long survival of Acinetobacter calcoaceticus

Environmental surface and personnel hand impression cultures were obtained during 13 sampling periods in the University of Virginia Pediatric Intensive Care Unit to document potential reservoirs of nosocomial pathogens. In 78 environmental cultures Staphylococcus aureus was found eight times and gram-negative bacilli ten times. The patient chart cover was the most commonly contaminated surface. Acinetobacter calcoaceticus was found in five of ten cultures positive for gram-negative bacilli. Thirty of 59 hand cultures were positive for S aureus and gram-negative bacilli; nurses and residents had both, respiratory therapists only gram-negative bacilli, and A calcoaceticus was the most commonly isolated bacterium of potentially nosocomial significance (14/30). Laboratory investigation of bacterial survival revealed that gram-negative bacilli survived on a dry formica surface from a few hours up to three days but Acinetobacter survived up to 13 days. Since A calcoaceticus has been implicated in many nosocomial infections, its long survival on a dry surface may be an additional factor in its transmission in hospitals and suggests that more attention be paid to environmental surfaces as a source of significant nosocomial pathogens.