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T Vehmas

Publications and source records attributed to T Vehmas.

12 recordsLinked to original sources
PubMed1992

Reflux of ethanol during experimental liver ethanol injections.

RATIONALE AND OBJECTIVES: The reflux of ethanol into the peritoneal cavity during percutaneous ethanol injection therapy (PEIT) of liver neoplasms may cause pain and other side effects. This article studies the optimal injection technique to minimize the reflux of ethanol. METHODS: A technique using normal postmortem pig livers was developed to measure the amount of reflux in different experimental injection situations. RESULTS: The proportional reflux increased significantly when the needle diameter (0.55-1.1 mm) was larger (P < .01) and when the injection was more superficial (P < .0005) (ie, the needle traversed a shorter distance [1-5 cm] inside the liver tissue). Speeding up the injection (0.13-1.5 g/second) produced suggestive (P < .10) increase of the proportional reflux. The proportional reflux was not affected by either the ethanol dose (0.40-2.06 g) or by the time lapse (0-30 seconds) after the injection when the needle was left in situ before its withdrawal. CONCLUSIONS: The reflux of ethanol during PEIT is influenced by the diameter of the needle and by the technique used. Further studies are needed to fully clarify the clinical validity of these results.

Animals↗
PubMed1992

Measuring radiation exposure during percutaneous drainages: can shoulder dosemeters be used to estimate finger doses?

Some previous studies have shown remarkably high finger doses to radiologists performing percutaneous drainage under fluoroscopy. To assess the possible need for extra finger dosemeters in addition to the general dosemeter, radiologists' and assistants' radiation exposure at both shoulders and at the third fingers of both hands were recorded using thermoluminescent dosemeters during 27 interventional drainage procedures. Under couch screening was used. Mean dose rates were calculated by dividing the doses by the screening time. The dose rates for the sites measured were correlated with each other. The radiologists' bilateral finger dose rates did not correlate with each other; nor did dose rates between the left shoulder and the right hand. The radiologists' dose rates at both shoulders, however, correlated with each other, as did the shoulder dose rates with the dose rates at the ispilateral hand. The right shoulder dose rates correlated with the left hand dose rates. The assistants' dose rates at the places of measurement all showed significant correlations with each other. It is therefore concluded that radiologists involved in percutaneous drainages should use finger dosemeters on both hands; for assistants this may not be necessary.

Drainage↗
PubMed1991

Radiation exposure during percutaneous nephrostomy.

Radiation doses of radiologists, assistants and patients during 21 percutaneous nephrostomies (PN) (including 11 unilateral and 5 bilateral procedures) were measured using an area-exposure meter and thermoluminescent dosimeters. The mean fluoroscopy time per PN was 12 min and the mean product of air kerma and the cross-sectional area of the fluoroscopic beam was 8.0 (range 0.41-24) Gycm2. Doses to the radiologists and assistants were generally modest, and the yearly dose limits of ICRP will not be exceeded in practice. The doses to the radiologist's fingers were found to be the most restrictive in this study. Regarding the mean dose to the radiologist's fingers (190 muGy), the yearly dose limit of 500 mSv would be exceeded after about 2600 PNs provided that his fingers are not otherwise exposed. With the maximal finger dose of 1100 muGy, this would occur after about 450 yearly PNs.

Adult↗
PubMed1991

Finger doses during interventional radiology: the value of flexible protective gloves.

Finger doses of radiologists and assistants during 19 interventional radiological procedures were measured with thermoluminescent dosimeters (TLDs), and two types of flexible protective gloves were compared with each other. There were considerable differences in doses between different sites of TLDs on fingers. The exact site of TLDs on hands/fingers should thus be reported in papers. Both gloves were also irradiated through an Alderson phantom and the attenuation values were measured. The gloves with slightly greater attenuation proved to be significantly less comfortable to use. Wearing flexible protective gloves did not lengthen screening times as compared to a previous study in the same department. Various aspects of using such gloves are discussed. The attenuation values of gloves reported by the manufacturers may not apply under all clinical circumstances.

Adult↗
PubMed1991

Correlations between findings at computed tomography (CT) and at thoracoscopy/thoracotomy/autopsy in pleural mesothelioma.

Thirty five computed tomography (CT) scans of the thorax and upper abdomen of thirty three patients with malignant pleural mesothelioma were correlated with the findings at thoracotomy (28 patients), thoracoscopy (2 patients) or autopsy (5 patients). Pleural thickening with contrast medium enhancement was detected on the CT scans of all patients. This finding was a valuable diagnostic tool, especially in cases of large amounts of pleural effusion and/or only thin layers of tumour barely or not at all visible on plain film chest X-rays. Difficulties in defining the exact extent of the diseases for clinical staging and/or evaluation of treatment response arose at the following sites: diaphragmatic pleura, chest wall, pericardium, mediastinum and mediastinal lymph nodes. Extension into the lung was difficult to identify following chemo- and/or radiotherapy. Our results show that CT is essential in the clinical management of mesothelioma. We recommend that CT scans of the chest and upper abdomen, using contrast medium enhancement, should be required in routine practice and in particular in clinical trials involving pleural mesothelioma.

Adult↗
PubMed1990

Percutaneous nephrostomy in the management of urinary leakages and fistulas.

Treatment with percutaneous nephrostomy (PN) without co-existing stents was attempted in 18 patients with urinary fistulas and leakages. Seven patients were cured by PN alone. Two of these developed a ureteral stricture at the site of the lesion: one showed no impairment of urinary flow on the follow-up, the other needed continuous urological surveillance. In the remaining 6 cases PN provided temporary relief of the associated urinary stasis. Percutaneous nephrostomy could not be applied in 5 cases because of the lack of renal pelvic dilatation. Only catheter related complications occurred. Because of its easy and little traumatic technique, simple PN could be used as the primary therapeutic approach in such lesions.

Adult↗
PubMed1990

Percutaneous evacuation of abdominal abscesses and fluid collections--aspiration or catheter drainage?

Ninety-three abdominal abscesses and fluid collections (pseudocysts, hematomas and bilomas) in 79 patients were treated under radiological guidance, for a total of 111 procedures (23 needle aspirations (NA) of 17 foci and 88 catheter drainages (CD) of 84 foci). In eight foci both methods were used. Catheter drainage was curative in 65% of abscesses and in 56% of pseudocysts and improved the patients' condition before surgery in another 11% or 10%, respectively. The aim of CD could not be achieved in 24% of the abscesses and in 34% of the pseudocysts. Needle aspiration showed little effect being curative in only 6% and partially beneficial in 24% as all the foci were considered. Complications occurred in 8% of CD:s and in 0% of NA:s. We suggest that radiologically guided CD of abscesses and fluid collections should be the primary therapeutic approach in all cases where this can be performed safely. The therapeutic effect of NA was poor.

Abdomen↗
PubMed1988

Results and complications of percutaneous nephrostomy.

A series of 181 patients (158 with obstructive uropathy) treated by percutaneous nephrostomy (PN) in 1978-1987 is evaluated. In 8.3% of the patients PN did not succeed. The success rate of PN was lower when done outside normal working hours and before ultrasound guidance was used. Major complications occurred in 5.5% and minor ones in 10.5%. There was no direct mortality. The complications and the possible avoidance of them are discussed. In 68% of patients nephrostomy improved their clinical condition. The benefit of PN was closely related to the existing renal recovery potential following the relief of obstruction; a problem that has not yet been fully solved.

Adolescent↗
PubMedDate not supplied

Ultrasound in renal pyogenic infection. Imaging and intervention.

A series of 34 patients with renal or perirenal pyogenic infection (18 with pyonephrosis, 10 with renal abscess and 6 with perirenal abscess) is presented to evaluate diagnosis with ultrasound and treatment with percutaneous ultrasound guided aspiration/drainage. Specific findings, defined as sediment echoes or dispersed internal echoes in a hydronephrotic renal collecting system, were noted in 39 per cent of pyonephrosis cases. Abscesses were mainly round or oval hypoechoic lesions measuring from 2 to 15 cm in diameter. Two abscesses were multilocular and one showed a septum. The appearance suggested tumor in 25 per cent. Because of this non-specificity of ultrasound we recommend diagnostic aspirations and further radiologic and other examinations in difficult cases. Four patients were treated by conservative means only, 13 with percutaneous aspiration or drainage, 9 with a combined drainage procedure and surgery, and 8 surgically. The length of the mean hospital stay was shortest in the group with the percutaneous drainage procedure (PDP) although the difference was not statistically significant. PDP was not effective in 12 per cent and surgery was used in these two cases to ensure cure. Complications occurred more often in the PDP group than in the surgery group but the most serious complication was a post-operative one. The different modes of treatment are discussed. The overall mortality was 5.9 per cent.

Abscess↗