Biomedical subjects

R Peer

Publications and source records attributed to R Peer.

At least 19 recordsLinked to original sources

PubMed2006

Relevant training issues for introduction of digital radiology: results of a survey.

Council Directive 97/43/Euratom establishes the need for adequate training of radiology staff. The transition to digital radiology implies changes in various imaging aspects, which are not sufficiently covered by current institutional training programmes. This work aimed to assess how professionals, experienced in digital imaging, acquired their expertise and hence, what form institutional training should take. Within DIMOND III, a survey on training and resources was performed among radiology professionals. A lack of institutional education for digital radiology was found. In the transition to digital radiology, 30-35% train on the job and another 23-28% receive training from digital equipment vendors. A general agreement exists on the need for new quality criteria and strategies for dose management. Issues relevant for conventional/digital transition are only sparsely covered in EC training programmes. Based on these results, a set of training issues was produced, to be included in future European guidelines.

Education, Medical, Continuing↗

PubMed2005

Craniotomy during ECMO in a severely traumatized patient.

Extracorporeal membrane oxygenation (ECMO) can be a last resort treatment in acute respiratory distress syndrome after thoracic trauma. However, co-existent brain trauma is considered to be a contra-indication for ECMO. This is the first report on successful craniotomy under ECMO treatment in a multiply traumatized patient with severe thoracic and brain injuries. This successful treatment with beneficial neurological outcome suggests that ECMO therapy should not be withheld from severely injured patients with combined brain and thoracic trauma presenting with life-threatening hypoxemia. Moreover, even craniotomy may be performed during ECMO therapy without major bleeding and adverse effects on neurological function.

Accidental Falls↗

PubMed2002

[Distal radius fractures and concomitant lesions. Experimental studies concerning the pathomechanism].

Since Colles (1814) first described a distal radius fracture and the publication by Dupuytren (1834), the frequency of and problems surrounding these fractures were increasingly recognised. Not only the treatment but also the formation and type of fracture were repeatedly analysed. The various theories concerning the pathomechanism led to names such as: "tear fracture", "bend fracture", "thrust fracture", "compression fracture", "snap fracture" and others. In our experimental studies we attempted to simulate the pathomechanism of distal radius fractures and present them pictorially. With the help of a materials testing machine, 63 prepared cadaver arms were hyperextended in the wrist joint until a radius fracture occurred. The concomitant lesions were registered radiologically and by dissection. Moreover, additional cadaver arms were deep-frozen and examined by means of computer tomography and cryosection according to Kathrein. Through experimental hyperextension it was possible to generate dorsal, central, and palmar types of fractures. We produced 42 dorsal, 14 central and 7 palmar fractures. Fundamentally, it seems that the fracture depends on the extent in which the carpal bones of the proximal row are pressed against the dorsal, central or palmar part of the articular surface of the distal radius. The subsequent dissection showed in 40 cases (63 %) mostly multiple concomitant lesions and in 23 cases (37 %) none of these. The reason for concomitant lesions may be the proportion of bone stability to the strength of ligaments. Most frequently (27 cases, i.e. 43 %), we found a destabilisation of the articular disk with or without a bony avulsion fragment (fracture of the ulnar styloid). We also commonly found ruptures of the interosseous ligaments between scaphoid and lunate (20 cases, i.e. 32 %) and lunate and triquetrum (11 cases, i.e. 18 %). It is difficult to apply knowledge gained from experimental studies on preserved cadaver arms clinically. There are of course no physiological reflexes and the slow fracture process must be taken into consideration. This holds true not only for concomitant lesions but also for the type of fracture. On the other hand, in these experimental studies it was possible to generate many realistic types of fractures with their concomitant lesions.

Biomechanical Phenomena↗

PubMed2001

Necrotizing fasciitis with Clostridium perfringens after laparoscopic cholecystectomy.

Necrotizing fasciitis is a rapidly progressive infection of the fascia and subcutaneous tissues accompanied by a high mortality rate approaching 80% to 100%. Factors that predispose patients to this life-threatening complication include obesity, malnutrition, malignancy, chronic alcoholism, drug abuse, peripheral vascular disease, diabetes mellitus, and immunosuppressive therapy. The pathomechanisms for the development of this rare disease still remain unclear. We report a case of necrotizing fasciitis with Clostridium perfringens after laparoscopic cholecystectomy. The patient left the hospital 5 months after admission. Early recognition based on clinical signs (pain, asymmetric abdominal thickening, crepitus) and computed tomography scanning (gas dissection along fascial planes), in conjunction with prompt, aggressive surgical therapy and debridement of all devitalized tissue, high-dose antibiotic therapy, and therapy at the intensive care unit, appears to afford patients the best chance of survival.

Cholecystectomy, Laparoscopic↗

PubMed2001

Nipple complication caused by a mesenteric GORE-TEX sling reinforcement in a Kock ileal reservoir: report of a case.

INTRODUCTION: The surgical trend after proctocolectomy at present is to perform a pelvic pouch reservoir with an ileoanal anastomosis. Before that a continent ileal Kock pouch was the procedure of choice, which enabled the patient to collect the intestinal discharge for several hours and avoid involuntary escape of reservoir contents, thus making the wearing of plastic bags unnecessary. Although in the majority of patients an increased life quality can be observed, different complications with a Kock pouch may occur. METHODS: We present a case of a young female with signs of outlet obstruction several years after a Kock reservoir was performed because of complicated ulcerative colitis. The obstruction was caused by a fecal-coated GORE-TEX sling that had penetrated through the nipple-valve base into the pouch. The mesenteric sling was introduced as a modification of the original Kock procedure to reinforce the efferent ileal segment, thus preventing nipple prolapse. The perforation site was closed with interrupted sutures and an ileostomy was performed. RESULTS: Three months thereafter, the ileostomy was closed and at a follow-up visit one year later the patient had no complaints and a well-functioning reservoir. CONCLUSION: If continence is desired after definitive ileostomy or if failure of the ileoanal reservoir occurs, a Kock pouch procedure still has a place in the surgical armamentarium of colorectal surgery. Many experts today do not use sling reinforcement maneuvers, and most of these procedures seem to work well without it.

Adult↗

PubMed2001

[Radiation exposure in single slice and multi-slice spiral CT (a phantom study)].

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.

Equipment Design↗

PubMed2001

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.

Humans↗

PubMed2001

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.

Humans↗

PubMed2001

Improved scintigraphic assessment of occult leakages in adjustable gastric bands using 99mTc-labelled human albumin colloid.

BACKGROUND: Adjustable gastric banding has become the preferred procedure in Europe for the treatment of morbid obesity. A complication of this treatment is the presence of leakage in the system. The knowledge of the localization of the leak is essential for planning the reoperation procedure. PATIENTS AND METHODS: In a series of 325 adjustable gastric bandings, we observed 10 band leakages. In 3 cases, fluoroscopy failed to detect fluid extravasation. We present a sensitive and simple scintigraphic method for the detection of gastric band leakage in these patients using 37 MBq of a 99mTc-human albumin colloid suspension. Imaging was started immediately after the dose application. During the first minute, images were acquired dynamically with 1 frame every 2 seconds. Afterwards, a static image was obtained every 10 minutes, up to 60 minutes post-injection. Then the system was emptied completely to detect tracer extravasation and consecutive reabsorption during 60 minutes. The study was analyzed by using the regions of interest (ROI) technique drawn on the following points: injection reservoir, tube, anterior band, posterior band, and an adjacent region which was taken as background. RESULTS: During the first hour, ROI analysis showed a clear diminution in the number of counts contained in the defect parts of the band, whereas it remained constant in the other locations. After system emptying, detection of tracer extravasation further strengthened the diagnosis of band leakage in all patients. CONCLUSION: This new approach using the 99mTc-human albumin colloid suspension with ROI analysis is an effective and simple method to detect occult leakages in adjustable gastric bands which escaped detection by fluoroscopy. In contrast to previously described scintigraphic methods, this investigation is able to demonstrate the exact site of leakage.

Adult↗

PubMed2001

Is a routine liquid contrast swallow following laparoscopic gastric banding mandatory?

BACKGROUND: The authors assess the value of liquid contrast medium swallow as a method to detect postoperative complications after laparoscopic adjustable gastric banding (LAGB) for the treatment of morbid obesity. METHODS: From January 1996 to January 2001, 350 morbidity obese patients (295 women, 55 men) underwent a LAGB operation. All data were prospectively collected in a computerized databank. All patients underwent a jopomidol swallow (JS) study in the early postoperative phase to exclude perforation of the esophagus or stomach, which is one of the most serious complications occurring after the LAGB operation. Furthermore, the JS was performed to confirm band position and to exclude early pouch dilatation. RESULTS: Out of the 350 LAGB operations, 6(1.8%) early pouch dilatations and 4(1.2%) stomach perforations occurred. All early pouch dilatations were recognized on postoperative JS and immediately repaired laparoscopically. Of the perforations, one was recognized intraoperatively, and the other three were diagnosed postoperatively, either by contrast media extravasation on the JS (two patients) or by computer tomography. CONCLUSION: Presently, all patients undergo routine postoperative JS, which exposes them to radiation, causes patient discomfort, and entails additional costs of approximately 100 US$ per patient. Of the last 250 patients in our series, there have not been any cases of early pouch dilatation and since 1998 only one case of perforation has occurred, which could be easily suspected clinically. Therefore, we believe that in experienced centers, it is not necessary to perform routine postoperative contrast media studies and recommend JS only in cases of complicated postoperative courses.

Adult↗

PubMed2001

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.

Computer Terminals↗

PubMed2000

[Multiple organ failure following inhalation of butane gas: a case report].

Most cases of acute poisoning by butane and other volatile compounds occur in young people as a consequence of substance abuse by inhalation. Clinical symptoms are caused by asphyxia and mainly affect the cardiovascular, respiratory and central nervous system. There are also reported deaths from intoxication of butane inhalation, mostly by cardiac arrhythmia. We report the case of a healthy 14 year-old boy who inhaled butane gas from an aerosol can for refilling cigarette lighters. Despite successful resuscitation and defibrillation, he died two days later from multiple organ failure involving the central nervous system, cardiovascular system, pulmonary system and the liver. Although such incidents are rare in middle European countries, emergency and intensive care medicine staff should be instructed on the consequences and management of butane gas poisoning.

Adolescent↗

PubMed2000

Gastroscopic band removal after intragastric migration of adjustable gastric band: a new minimal invasive technique.

BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) is the most used procedure for bariatric surgery in Europe. Although a low complication rate is reported, band migration within the first 2 years after LAGB is still observed in nearly 5% of cases, requiring operative band removal. To avoid increased risk of complications due to laparotomy, we propose a minimally invasive technique for this purpose. METHODS: We performed this operation in five patients who suffered from band migration after LAGB (1.9% in our series of 211 patients, one patient was operated elsewhere). The described method consists of gastroscopic band and tube removal, combined with removal of the port under local anesthesia. RESULTS: The described procedure was developed in the endoscopy unit without additional equipment. The mean operating-time ranged from 65 to 180 minutes (mean 135 minutes). No perioperative complication were observed. In-patient treatment was necessary for 4 days. CONCLUSIONS: A novel technique for minimally invasive band removal after adjustable gastric band migration is described, offering the patient a low-risk procedure and a better chance for further laparoscopic approaches.

Adult↗

PubMed1999

Sophisticated hospital information system/radiology information system/picture archiving and communications system (PACS) integration in a large-scale traumatology PACS.

Picture archiving and communications system (PACS) in the context of an outpatient trauma care center asks for a high level of interaction between information systems to guarantee rapid image acquisition and distribution to the surgeon. During installation of the Innsbruck PACS, special aspects of traumatology had to be realized, such as imaging of unconscious patients without identification, and transferred to the electronic environment. Even with up-to-date PACS hardware and software, special solutions had to be developed in-house to tailor the PACS/hospital information system (HIS)/radiology information system (RIS) interface to the needs of radiologic and clinical users. An ongoing workflow evaluation is needed to realize the needs of radiologists and clinicians. These needs have to be realized within a commercially available PACS, whereby full integration of information systems may sometimes only be achieved by special in-house solutions.

Ambulatory Care Facilities↗

PubMed1999

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

The aim of this study was comparative analysis of rejected radiographs in conventional and digital radiology under the aspects number of rejected images and reasons for rejection. During 2 months waste films of conventional radiography were collected; in digital radiography each image-delete command at the postprocessing workstation was documented. Rejected images were analysed and assigned to four categories. The overall reject rate was 27.6% in the conventional and 2.3% in the digital department. Whereas 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". The high exposure tolerance of digital systems markedly reduces the amount of faulty images. This is not only economically rewarding, but may also reduce unnecessary X-ray exposure of patients due to image retake.

Humans↗

PubMed1998

Premature peripheral vascular disease: clinical profile and abnormal lipid peroxidation.

The aim of this study was to determine any biochemical differences between early-onset peripheral vascular disease and typical onset atherosclerosis, and age-matched controls. A subset of patients present at a young age ( < 50 years) with peripheral vascular disease which pursues an aggressive course. As lipid oxidation seems important in atherosclerosis, total lipid peroxides, oxidized subfractions, and Trolox equivalent antioxidant capacity (TEAC) were studied in patients with premature peripheral vascular disease. Charts were reviewed of patients operated on for vascular occlusive disease over a 5-year period. Patients with early-onset peripheral vascular disease (group I) were evaluated for biochemical abnormalities and compared with typical onset atherosclerotics (group II) and age-matched controls (group III). Sixteen patients with early-onset peripheral vascular disease underwent biochemical evaluation. Conventional lipid profiles did not differ statistically from those of age-matched controls, except for mild elevations in LDL and VLDL in patients with vascular occlusive disease (207 and 195 mg/dl in groups I and 11 versus 157 mg/dl in group III). Total oxidative potential was significantly elevated (P = 0.006) 3.04, 2.15 and 2.04 nmol/ml in groups I, II and III, respectively. Levels of oxidized LDL and VLDL were even more significantly elevated (P = 0.0009) for premature peripheral vascular disease, (1.2, 0.58 and 0.47 nmol/ml in groups I-II). TEAC values did not differ significantly between groups (0.83, 0.82, 0.82 nmol/ml) and did not correlate with total lipid peroxide values for individual patients. In conclusion, lipid peroxides were significantly elevated in patients with premature peripheral vascular disease, the most marked changes being seen in oxidized LDL and VLDL subfractions. Lipid peroxides were elevated when standard lipid profiles were only mildly abnormal. The poor long-term prognosis in these patients suggests the need for aggressive evaluation and treatment of lipid abnormalities.

Adult↗

PubMed1998

[First experiences with the trauma radiologic PACS project at the University of Innsbruck Department of Radiology].

Radiography in an emergency setting is a demanding task, in technical as well as in logistical terms. Rapid acquisition of high quality radiographs under difficult conditions, for example severely injured patients with multi-organ trauma is important. All image data and radiological reports must be transmitted to the trauma surgeon as soon as possible. To meet these needs with the promising means of modern X-ray technology, we decided to implement a completely digital X-ray division inside the new outpatient trauma department. In the setting of an outpatient emergency department digital radiography and PACS cannot be realised without problems. We present our first experience with the installation and 10 month filmless routine in the X-ray division for traumatology outpatients at the university of Innsbruck department of radiology.

Emergencies↗

PubMed1997

Leiomyosarcoma of the inferior vena cava: a clinicopathologic review and report of three cases.

BACKGROUND AND OBJECTIVES: We operated on three patients with leiomyosarcoma of the inferior vena cava. METHODS: Complete excision was possible in all three patients. RESULTS: One patient developed widespread metastasis at 23 months, one patient is alive with no evidence of disease at 70 months, and one patient is alive at 15 months. The third patient had subcutaneous and pulmonary metastases at the time of presentation, which are radiologically nondetectable at present following postoperative chemotherapy. CONCLUSIONS: The clinicopathologic features, prognostic factors, and treatment of 130 cases found in a comprehensive literature search and our three cases are reported.

Aged↗