Gender differences in health-related quality of life on admission to a maintenance treatment program.

We compared the gender differences in health-related quality of life (QOL) on admission to a maintenance program. 103 opioid users (65 men and 38 women) admitted to a maintenance treatment program during 2000-2002 were studied. During this period we assessed the QOL status using the German version ('Berlin Quality of Life Profile') of the Lancashire Quality of Life Profile. Physical symptoms were measured using the Opioid Withdrawal Scale. 312 urine screening tests were carried out to evaluate consumption. The female group showed significantly less additional consumption of other opiates (p = 0.043) compared with the male group. The male group showed significantly better QOL scores in self-esteem (p = 0.015), psychical health (p = 0.027), and law and security (p = 0.008). The outcome measures for withdrawal scores showed significantly less symptoms for males in twitching of muscles (p = 0.034), vomiting (p = 0.002), depressions (p = 0.004) and poor appetite (p = 0.008). In summary, both genders showed only a few significant differences on admission in terms of QOL and physical symptoms. The predominant effects of drug use appear to eclipse the gender-related role pattern. Further exploration of gender and QOL could have important theoretical and treatment implications.

Buprenorphine versus methadone maintenance treatment in an ambulant setting: a health-related quality of life assessment.

BACKGROUND: To compare the effects on quality of life (QOL) of oral methadone with sublingual buprenorphine. METHODS: We performed an open-label, non-randomized, two-site (methadone-buprenorphine) study. During 6 months we assessed the quality of life status of 53 opioid-dependent patients admitted to a methadone or buprenorphine maintenance programme using the German version (Berlin Quality of Life Profile) of the Lancashire Quality of Life Profile. Physical symptoms were measured using the Opioid Withdrawal Scale. Five hundred and thirty urine screening tests were carried out randomly to detect additional consumption. RESULTS: Sixty-seven opioid-dependent subjects (38 on methadone and 29 on buprenorphine) were enrolled in the study, and 53 completed it (30 subjects treated with buprenorphine and 23 subjects with racemic methadone). The subjects were comparable on all baseline measures. At the first follow-up (week 8), the buprenorphine-maintained group showed significantly less additional consumption of opioids (P = 0.013) compared with the methadone group. Patients retained in the buprenorphine or methadone programme (week 24) showed no significant differences in all quality of life scores. At the end of the study period, the buprenorphine-maintained group showed significantly less additional consumption of opioids (P = 0.001) and cocaine (P = 0.018) compared with the methadone group. The outcome measures for withdrawal symptoms after 24 weeks of treatment with buprenorphine showed slight advantages in stomach cramps, fatigue or tiredness, feelings of coldness and heart pounding. CONCLUSIONS: These results suggest that buprenorphine treatment is as effective as methadone regarding effects on quality of life and withdrawal symptoms. Buprenorphine has the potential to reduce the harm caused by drug abuse. Further research is needed to determine if buprenorphine is more effective than methadone in particular subgroups of patients.

[Radiation exposure in single slice and multi-slice spiral CT (a phantom study)]. / Untersuchungen zur Strahlenexposition bei der Einzelschicht- und Mehrschicht-Spiral-CT (eine Phantom-Studie).

PURPOSE: The purpose of study was to compare patient dose applying singleslice- and multislice-spiral CT. METHODS: The examinations were performed with a singleslice-spiral CT (Highspeed Advantage; GE Medical Systems; Milwaukee, USA) and with a multislice CT systems (LightSpeed QX/i GE Medical Systems; Milwaukee, USA). For the determination of the radiation exposure (absorbed dose) a selection of most executed protocols (thorax-helical, abdomen-helical, petrous bone-axial, head-axial) were simulated using an Alderson Rando Phantom. The dose was determined by means of lithiumfluorid-thermoluminiscence dosimeters (TLD-GR 200). RESULTS: For thorax and abdomen protocols higher energy dose values could be found using a multislice CT. On the average the energy dose values were increased by 2.6 on an average in relation to single slice spiral CT. The energy dose values of the multisclice CT using head protocols could be reduced by 30% in relation to single slice spiral CT due to suitable parameter selections. The energy dose applying a petrous bone protocol resulted in an average increase by a factor 1.5 using a multislice CT. CONCLUSION: Using the new multislice CT technique protocol strategies must be optimized regarding the patient doses. Users can operate critically in the sense of the radiation protection only if they are aware of the occurring dose amounts to the patient.

Psychophysical aspects in medical illumination techniques.

The relation between image and visual perception of the human eye is an important point in digital imaging systems. Research aims should therefore pay attention to psychophysical aspects. Optimising of digital imaging systems can only be reached if the important final steps in the diagnostic process--visual perception and signal detection--are taken into account.

Comparative reject analysis in conventional film-screen and digital storage phosphor radiography.

The purpose of this work was to gather information about the benefits in patient care caused by the introduction of digital radiography. In particular, the possibility of reducing the number of image repeats and thus unnecessary patient radiation was sought. Waste films of conventional radiography were collected--in digital radiography each image delete command at the post-processing workstation was documented. Rejected images were analysed retrospectively. The overall reject rate was 27.6% in the conventional and 2.3% in the digital department. While in the conventional department the main reason for rejection was 'exposure' and 'others' (i.e. problems related to film handling), the main reason in the digital environment was 'positioning'. Reject analysis yields representative data about the current performance of a radiology department. A marked reduction of repeated X rays and consequently reduced radiation exposure of the patient was clearly shown in this study comparing two differently working radiology departments. This is one of several benefits of digital radiography in patient care.

Comparison of low-contrast detail perception on storage phosphor radiographs and digital flat panel detector images.

A contrast detail analysis was performed to compare perception of low-contrast details on X-ray images derived from digital storage phosphor radiography and from a flat panel detector system based on a cesium iodide/amorphous silicon matrix. The CDRAD 2.0 phantom was used to perform a comparative contrast detail analysis of a clinical storage phosphor radiography system and an indirect type digital flat panel detector unit. Images were acquired at exposure levels comparable to film speeds of 50/100/200/400 and 800. Four observers evaluated a total of 50 films with respect to the threshold contrast for each detail size. The numbers of correctly identified objects were determined for all image subsets. The overall results show that low-contrast detail perception with digital flat panel detector images is better than with state of the art storage phosphor screens. This is especially true for the low-exposure setting, where a nearly 10% higher correct observation ratio is reached. Given its high detective quantum efficiency the digital flat panel technology based on the cesium iodide scintillator/amorphous silicon matrix is best suited for detection of low-contrast detail structures, which shows its high potential for clinical imaging.

[Subjective wellbeing and somatic markers in methadone substitution. Evaluation of 61 heroin addicts]. / Subjektives Wohlbefinden und somatische Merkmale bei Methadonsubstitution. Evaluierung bei 61 Heroinabhängigen.

AIM: In 61 patients with the ICD-10 diagnosis "heroin dependence" an evaluation of subjective well-being with consideration given to coexisting symptoms prior to and 4 months after initiation of methadone maintenance. METHOD: The Lancashire Quality of Life Profile and, for the clinical physical side effects, the opioid withdrawal scale proposed by Bradley and Seldenburg, were used. Additionally, urinalysis was performed. RESULTS: Statistically appreciable differences were found between the two groups in terms of drug-specific side effects, somatic satisfaction scales, and consumption of medications and co-use of addictive drugs. Further statistically evident inter-group differences were seen with regard to mental well-being. CONCLUSION: Overall, methadone maintenance leads to a rapid improvement in subjective well-being and to a relevant reduction in concurrent physical symptoms.

Computer-assisted neurosurgery by using a noninvasive vacuum-affixed dental cast that acts as a reference base: another step toward a unified approach in the treatment of brain tumors.

OBJECT: The purpose of the study was to evaluate the use of the Vogele-Bale-Hohner (VBH) mouthpiece, which is attached to the patient's upper jaw by negative pressure, for patient-image registration and for tracking the patient's head during image-guided neurosurgery. METHODS: A dynamic reference frame (DRF) is reproducibly mounted on the mouthpiece. Reference points, optimally distributed and attached to the mouthpiece, are used for registration in the patient's absence on the day before surgery. In the operating room, the mouthpiece and DRF are precisely repositioned using a vacuum, and the patient's anatomical structures are automatically registered to corresponding ones on the image. Experimental studies and clinical experiences in 10 patients confirmed repeated (rigid body) localization accuracy in the range of 0 to 2 mm, throughout the entire surgery despite movements by the patient. CONCLUSIONS: Because of its noninvasive, rigid, reliable, and reproducible connection to the patient's head, the VBH vacuum-affixed mouthpiece grants the registration device an accuracy comparable to invasive fiducial markers.

Virtual computed tomography colonoscopy: artifacts, image quality and radiation dose load in a cadaver study.

The purpose of our study was to evaluate the interdependency of spatial resolution, image reconstruction artifacts, and radiation doses in virtual CT colonoscopy by comparing various CT scanning protocols. A pig's colon with several artificial polypoid lesions was imaged after air insufflation with helical CT scanning using 1-, 3-, and 5-mm collimation, and pitch values varying from 1.0 to 3.0. Virtual endoscopic images and "fly through" sequences were calculated on a Sun Sparc 20 workstation (Navigator Software, GE Medical Systems, Milwaukee, Wis.). Several reconstruction artifacts as well as overall image quality were evaluated by three independent reviewers. In addition, radiation doses for the different CT protocols were measured as multiple-scan average dose using a 10-cm ion chamber and a standard Plexiglass body phantom. Generally, image quality and reconstruction artifacts were less affected by pitch values than by beam collimation. Thus, narrow beam collimation at higher pitch values (e. g. 3 mm/2.0) seems to be a reasonable compromise between quality of virtual endoscopic images and radiation dose load.

The Austrian Academic Computer Network and its usefulness for teleradiology.

To study the value of the Austrian Academic Computer Network (ACOnet) for teleradiology, 1740 test image data-sets and 620 image data-sets were exchanged between the departments of diagnostic radiology of the Universities of Innsbruck and Graz using the ACOnet service. Data transmission was reliable and fast with an average transfer capacity of 170 kByte/s (range 94-341). During the test phase, no major problems with image transfer occurred. Assuming that problems like security of patient data-sets, data compression and data verification can be solved, the ACOnet service would be a useful additional tool for telemedicine applications throughout Austria and eastern Europe.

[ACOnet (Austrian Academic Computer Network) as data carrier for teleradiologic consultations]. / Das ACOnet (Austrian Academic Computer Network) als Datenträger für teleradiologische Konsultationen.

PURPOSE: To assess the feasibility of image transfer for teleradiologic consultations using the Austrian Academic Computer Network (ACOnet). The ACOnet corresponds between the main universities to a MAN (Metropolitan Area Network) with a transfer rate of 4 Mbps. Its use is free of charge for university institutions. MATERIALS AND METHODS: 1740 test image data sets and 620 image data sets for teleradiological consultations were exchanged without annotations between the Departments of Diagnostic Radiology of the universities of Innsbruck and Graz, using the ACOnet. RESULTS: Data transmission was reliable and fast with an average transfer capacity of 170.2 kBytes/s (94-341 kBytes/s). There were no major problems with image transfer during the test phase. CONCLUSION: Due to its high transfer capacity, the ACOnet is considered a reasonable alternative to the ISDN service.

Virtual computed tomography gastroscopy: a new technique.

BACKGROUND AND STUDY AIMS: The aim of the present study was to establish a suitable method for virtual computed tomography (CT) gastroscopy. PATIENTS AND METHODS: Three-millimeter helical CT scans of a pig stomach were obtained after air insufflation and instillation of diluted diatrizoic acid (Gastrografin), and with double contrast. In addition, three patients with gastric tumors were studied after ingestion of an effervescent agent (Duplotrast, 6 g) and intravenous injection of hyoscine butylbromide (Buscopan, 1 ml). Virtual endoscopy images were computed on a Sun Sparc 20 workstation (128 megabytes of random access memory, four gigabytes of hard disk space), using dedicated software (Navigator, General Electric Medical System Company). The endoscopy sequences were compared with real endoscopic examinations and with anatomical specimens. RESULTS: In the cadaver studies, the best results were obtained with plain air insufflation, whereas virtual CT gastroscopy with diluted contrast and with double contrast showed artifacts simulating polyps, erosions, and flat ulcers. Patient studies showed good correlation with the fiberoptic endoscopy findings, although large amounts of retained gastric fluid substantially reduced the quality of the surface reconstruction. CONCLUSION: These preliminary results show that virtual CT gastroscopy is able to provide insights into the upper gastrointestinal tract similar to those of fiberoptic endoscopy. However, due to the limited spatial resolution of the CT protocol used, as well as inherent image artifacts associated with the Navigator program's reconstruction algorithm, the form of virtual CT gastroscopy studied was not capable of competing with the imaging quality provided by fiberoptic gastroscopy.

[Virtual endoscopy with post-processing helical CT data sets]. / Virtuelle Endoskopie mittels Postprocessing helikaler CT-Datensätze.

PURPOSE: The purpose of this work was to test a newly developed, post-processing software for virtual CT endoscopic methods. Virtual endoscopic images were generated from helical CT data sets in the region of the shoulder joint (n = 2), the tracheobronchial system (n = 3), the nasal sinuses (n = 2), the colon (n = 2), and the common carotid artery n = 1). Software developed specifically for virtual endoscopy ("Navigator") was used which, after a previous threshold value selection, makes the reconstruction of internal body surfaces possible by an automatic segmentation process. We have evaluated the usage of the software, the reconstruction time for individual images and sequences of images as well as the quality of the reconstruction. All pathological findings of the virtual endoscopy were confirmed by surgery. RESULTS: The post-processing program is easy to use and provides virtual endoscopic images within 50 seconds. Depending of the extent of the data set, virtual tracheobronchoscopy as a cine loop sequence required about 15 minutes. Through use of the threshold value-dependent surface reconstruction the demands on the computer configuration are limited; however, this also created quality problems in image calculation as a consequence of the accompanying loss of data. CONCLUSIONS: The Navigator software enables the calculation of virtual endoscopic models with only moderate demands on the hardware.

[Open questions on the topic of teleradiology from the current viewpoint]. / Offene Fragen zum Thema Teleradiologie aus aktueller Sicht.

A review on the theoretical challenges and potential risks of teleradiology is given. Based on the authors two years clinical experience and the current literature unsolved problems are discussed, which are to a smaller extent the technical implementation but much more the still missing regulation of various concomitant circumstances.

A cost analysis of an emergency computerized tomography teleradiology system.

We carried out a cost analysis of a teleradiology system for emergency computerized tomography (CT) examinations. Teleradiology was implemented by connecting two spiral CT scanners in the University Hospital in Innsbruck and the Regional Hospital in Zwettl. It enabled the remote hospital in Zwettl to get fast and competent reports of emergency CT examinations when there was no specialist radiologist available. In 13 months' use for routine night and weekend service, the system proved fast and reliable. During the study period 121 emergency examinations of 116 patients were transmitted from Zwettl to Innsbruck. The fixed costs of teleradiology were for the ISDN connection and amounted to DM230 plus DM696/year rental. The average cost of one emergency CT examination by teleradiology was DM372 (range 308-453). One possible alternative, transporting the films by taxi for reporting elsewhere, was cheaper (estimated cost DM156), but would have been much slower. Another alternative, transporting the patient to the nearest central hospital for scanning, was much more expensive: DM524 by road or DM4667 by helicopter ambulance.

[Virtual CT colonoscopy. Examination technique, limitations and perspectives]. / Virtuelle CT-Koloskopie. Untersuchungstechnik, Limitierungen und Perspektiven.

Virtual CT-colonoscopy is a post-processing method which allows for reconstruction of inner bowel surface structures from helical CT datasets. The reconstructed images simulate the views which are known from fiberoptic endoscopy. Since colorectal cancer is the second main cause of death in USA and Europe today and since recent screening recommendations are often ignored by the public, a non-invasive or minimal-invasive procedure for colonic evaluation would offer some benefits. Virtual CT-colonoscopy generally involves three essential steps: patient preparation with cleansing of the bowel and administration of an air enema, helical CT-examination by using appropriate scan parameters, and interactive 3D rendering of the volume data-set. Although recent studies have demonstrated that polypoid lesions of about 5 mm size are well detectable and although virtual colonoscopy offers many advantages over fiberoptic endoscopy, some technical and clinical limitations must still be noted. Thus, the current inability of virtual colonoscopy to provide texture and color leads to problems in identifying flat lesions; the presence of retained or adherent fecal matter may result to false positive diagnosis and collapsed segments of bowel may cause problems as they cannot subsequently be evaluated during image reconstruction. Virtual endoscopy is still in its infancy and further technical and clinical developments are necessary. Virtual CT-colonoscopy may then prove to be equal or superior to colonoscopy in sensitivity and specificity for polyp detection and be able to reduce the number of unnecessary colonoscopic procedures.