Biomedical subjects

L Kivisaari

Publications and source records attributed to L Kivisaari.

At least 73 records · Page 4Linked to original sources

PubMed1993

Intra- and peri-hepatic effects of ethanol injections in the pig liver.

We studied the intrahepatic (spread and scarring) and perihepatic effects of percutaneous ethanol injection therapy and its dose-necrosis relationship in normal pig livers. Ethanol (99.5%) was injected in volumes of 0.5-2.0 ml into the livers of six pigs during laparotomy. The livers were dissected and studied histopathologically 30 min and 2 weeks after the injections. Ethanol-induced liver necrosis, the diameter of which could roughly be calculated by dividing the injected dose by 2 (inversely: volume (ml) = 2 x diameter (cm)). Two weeks after the injections all pigs showed intra-abdominal adhesions and severe intrahepatic scar formation, unlike three control pigs similarly operated on without ethanol injections. The 30-min lesions showed thin projections extending into the neighboring liver tissue. Major escape of ethanol outside the needle tip area in the liver occurred twice. Uncontrolled spread of ethanol may be a potential hazard of this treatment.

Animals↗

PubMed1993

Contrast media-induced renal morphologic lesions in diabetic rats.

Diabetes mellitus was induced in rats with streptozotocin and after 3 months the animals (n = 48) received an i.v. injection of 1 or 3 g I/kg in the form of high-osmolar diatrizoate, low-osmolar iopromide or iohexol, or of 0.6 g I/kg of high-osmolar Gd-DTPA. The controls were given an i.v. injection of physiologic saline. After 2 hours the kidneys were fixed by perfusion and the renal morphologic changes were semiquantitatively analyzed by two independent observers unaware of the agent administered. The contrast media (CM) induced pronounced cytoplasmic vacuolization in the proximal convoluted tubular cells. Such a lysosomal alteration may indicate CM uptake into the cell, and the ultrastructural evaluation revealed intracellular injuries related to the process. The alterations were most marked following administration of iohexol, but diatrizoate also induced a statistically highly significant vacuolization (p < 0.001). The lysosomal alterations following iopromide administration were not as striking, and Gd-DTPA induced only minor changes.

Animals↗

PubMed1992

Clinical versus ultrasound examination of the thyroid gland in common clinical practice.

In a prospective series of 72 patients, clinical and ultrasonographic examination of the thyroid gland were compared in detail. Normal-sized lobes were differentiated from enlarged ones both by inspection and by palpation. When lobar size was assessed by palpation, the estimate was most clearly influenced by increase in width. The correlation between two examiners in lobe size assessment was significant. In the classification of thyroid disease as diffuse, solitary, or multinodular, clinical examination and ultrasonography correlated significantly. However, only one third of the clinically solitary nodules proved to be solitary by ultrasound examination. Of 77 separate nodules, 43 escaped detection on clinical examination. Of these 43, 14 nodules exceeded 2 cm in diameter. It is concluded that the use of ultrasonography frequently alters the primary evaluation of thyroid nodularity based on palpation.

Adolescent↗

PubMed1992

N-acetylcysteine in combination with radiotherapy in the treatment of non-small cell lung cancer: a feasibility study.

N-Acetylcysteine (NAC) is a free radical scavenger and could therefore act as a radioprotector. To test the feasibility of administering NAC in combination with radiotherapy, we studied 10 patients with inoperable non-small cell lung cancer who were receiving hyperfractionated radiotherapy (RT) of 1.25 Gy B.I.D. (6-h interval) up to a total dose of 60 Gy/48 fractions/32 days. They were given NAC concomitantly with RT: 100 mg/kg i.v. 30 min before the first RT session followed by 30 mg/kg as an i.v. infusion over 7 h; and 600 mg inhaled 30 min before and after each RT session. The patients were assessed by serial CT scans and lung function studies during a 1-year follow-up period. The treatment regime was feasible, but expensive in time and resources. Normal tissue reactions and tumour responses were similar to those in a control group.

Acetylcysteine↗

PubMed1992

Natural alpha-interferon in combination with hyperfractionated radiotherapy in the treatment of non-small cell lung cancer.

Our previous study in patients with small-cell lung cancer indicated that natural alpha interferon might be a radiosensitiser. In this study we considered 20 patients with inoperable non-small cell lung cancer, who were randomly assigned to receive either hyperfractionation radiotherapy alone, 1.25 Gy twice a day (6 hr interval), 60 Gy/48F/32d; or the same radiotherapy concurrently with alpha interferon. Patients in the radiotherapy+alpha interferon arm received 3 x 10(6) IU natural alpha interferon intramuscularly and 1.5 x 10(6) IU inhaled via a dosimeter-equipped jet nebulizer 30 min before each radiotherapy session. Tumor response and radiation-induced lung injury were assessed by serial chest radiographs, computerized tomography scans and lung function studies, during a 1 year follow-up period. No patient in either arm achieved complete response. On the other hand, five patients in the radiotherapy arm and six in the radiotherapy+interferon arm experienced partial response, and the corresponding figures for stable disease were three and one. Combined treatment with radiotherapy and inhaled and intramuscular interferon proved feasible but laborious, for both patients and staff. Pneumonitis and/or oesophagitis in the radiotherapy+interferon arm were moderate to severe, and only two patients tolerated the treatment without any modifications. No treatment modifications were necessary in the radiotherapy arm. The early deaths in the radiotherapy+interferon arm may have been treatment-related. The optimal way to combine interferon and radiotherapy to further evaluate its role as a radiosensitiser needs further studies in larger series.

Adenocarcinoma↗

PubMed1992

Multimodality treatment programs for malignant pleural mesothelioma using high-dose hemithorax irradiation.

The characteristic of malignant pleural mesothelioma is a tumor that grows by plate-like extension over the pleura, and invades adjacent tissues and organs. Radical surgical removal of the tumor is generally not possible, and most treatment regimens involve combined chemotherapy and radiotherapy, as well as debulking surgery. We have prospectively evaluated five locally-aggressive multi-modality treatment programs, using different hemithorax irradiation schedules and chemotherapy regimens. One hundred patients with confirmed malignant pleural mesothelioma entered the study between 1977 and 1989. The treatment programs, which can consecutively, were: I, 20 Gy (10 x 2 Gy) to the hemithorax + CYVADIC (cyclophosphamide 500 mg/m2 d 1, vincristine 1 mg/m2 d 1 and 5, adriamycin 40 mg/m2 d 1 and dacarbazine 200 mg/m2 d 1 and 5, several cycles before and after irradiation); II, 55 Gy (25 x 2.2 Gy) to the hemithorax + 15 Gy (6 x 2.5 Gy) to the tumor + CYVADIC (2 cycles before, 1 cycle during, and 2 cycles after irradiation); III, Mitoxantrone (14 mg/m2 q 28 d, < or = 6 cycles) followed by 70 Gy (56 x 1.25 Gy, twice a day); IV, 4-Epirubicin (110-130 mg/m2 q 28 d, < or = 6 cycles) followed by 35 Gy (28 x 1.25 Gy twice a day) to the hemithorax + 36 Gy (9 x 4 Gy every 2 days) to the tumor; V, Etoposide (150 mg/m2 1, 3, 5 q 28 d) followed by 38.5 Gy (11 x 3.5 Gy) to the hemithorax. A new system for evaluating tumor response in pleural mesothelioma was applied. None of the combined treatment programs prevented local invasive growth or the spread of mesothelioma outside the hemithorax. The median survival time was slightly increased from 8 to 12 months for those patients who completed the protocol treatments, but progressive disease was the invariable outcome. Radiation pneumonitis and fibrosis were severe and compatible with results of total loss of lung function on the irradiated side. We conclude that data relating to therapeutic responses and treatment programs in malignant mesothelioma should be better correlated internationally, if the problems associated with the evaluation of treatment and the management of patients with mesothelioma are to be improved.

Adult↗

PubMed1992

Contrast media-induced renal morphologic lesions during experimental hemorrhagic necrotizing pancreatitis.

RATIONALE AND OBJECTIVES: Contrast media-induced renal morphologic changes were studied in rats. Hemorrhagic pancreatitis was induced as a means of sensitizing the animals to the effects of contrast media. METHODS: The histologically verified hemorrhagic pancreatitis was induced in Wistar rats (n = 66) by injecting 6% sodium taurocholate into the pancreatic duct. After 2 hours, the animals received intravenously 1.0 or 3.0 g iodine/kg of high-osmolal osmolal diatrizoate, low-osmolal iopromide or iohexol, iso-osmolal iotrolan or 0.2 or 0.6 g/kg of high-osmolal magnetic resonance contrast agent, gadolinium-DTPA (Gd-DTPA). Control animals received physiologic saline. The kidneys were fixed by perfusion 2 hours later, and the morphologic changes were reviewed by two independent observers blinded to the injected agent. RESULTS: The smaller dose of iohexol and the larger dose of all the contrast media induced a statistically significant (P < .001 or .01) cytoplasmic vacuolization in the proximal convoluted tubule (PCT) cells. The nonionic, low- and iso-osmolal contrast media caused as much or even significantly more vacuolization than diatrizoate. CONCLUSIONS: Hemorrhagic pancreatitis potentiates the contrast media-induced renal morphologic changes, which depend on the type and dose of the injected contrast media.

Animals↗

PubMed1992

Level of plasma prekallikrein and its inhibitors in reactors and nonreactors during intravenous enhancement with contrast media.

Complex contact activation systems may play a major role in the side effects of i.v. contrast media (CM). This is why quantitative measurements of several factors (plasma prekallikrein, hematocrit (hct), alpha-2-macroglobulin, alpha-1-antitrypsin, and C1-esterase inhibitor) were determined prior to and following the injection of CM during body CT examination in 5 patient groups, each (n = 10) receiving one of 5 different CM, including ioxaglate, meglumine iodamide, metrizamide, iohexol, and meglumine diatrizoate. The initial plasma prekallikrein level was available from 45 patients and was statistically lower in reactors (mean 90.6 mumol TAMe/ml/h; n = 13) than in nonreactors (mean 107 mumol TAMe/ml/h; n = 32) (p = 0.006), but there was no statistically significant difference in the decrease of plasma prekallikrein before and at 5 min after the injection for those 2 groups. The initial plasma C1-esterase inhibitor level was lower in reactors, while the plasma alpha-2-macroglobulin level was higher in that group than in nonreactors. The results indicate that the measurement of plasma prekallikrein combined with plasma C1-esterase inhibitor and alpha-2-macroglobulin measurement could be useful when predicting which patients are prone to CM reactions.

Blood Proteins↗

PubMed1991

Vascular changes of pancreatic ducts and vessels in acute necrotizing, and in chronic pancreatitis in humans.

Five patients with severe acute pancreatitis (AP) underwent subtotal pancreatectomy, and six patients with advanced chronic pancreatitis (CP) were subjected to pancreatic resection. Microangiography and histological studies were performed on the resected pancreata. All patients with AP had histologically verified necrotizing pancreatitis. Pancreatic ducts in the necrotic areas had severe inflammation in their walls and a decrease in their vascularity. The ductal walls of CP patients were indistinguishable from the surrounding fibrosis and the vascular supply of the ducts was markedly diminished. The vessels were reduced in number, and their calibers varied considerably. Ductal ischemia in connection with AP and CP is discussed.

Acute Disease↗

PubMed1991

Procollagen-III in serum, plasminogen activation and fibronectin in bronchoalveolar lavage fluid during and following irradiation of human lung.

In the search for predictors of late radiation-induced lung injury we studied procollagen type III peptide concentration (P-III-P) in serum as well as fibronectin and plasminogen activation in bronchoalveolar lavage (BAL) fluid during and following irradiation of human lung. The patients received either high-dose hemithorax irradiation for pleural mesothelioma (11 patients) or high-dose irradiation with individually shaped fields for non-small cell lung cancer (12 patients). The severity of radiation fibrosis was assessed clinically from CT scans 6 months and 12 months after treatment. Four scores were used: severe, moderate, mild, or normal. Radiological lung injury varied from "severe" (9 patients) to near absence of injury-"normal" (6 patients). Serum levels of P-III-P, when measured weekly during the 5-week period of radiotherapy or at several time-points after treatment, did not show consistent changes, nor did the levels correlate with the score for radiation fibrosis as assessed by CT scanning. Changes in fibronectin levels or in markers of plasminogen activation in BAL fluid did not correlate with the development of late lung injury. The levels of BAL fluid plasmin and plasminogen activator as assessed zymographically, but not the free net enzyme values, showed a tendency to be elevated in patients with severe radiation-induced lung injury, suggesting a possible role for inhibitors of the plasminogen activation cascade in the process of radiation-induced lung injury.

Adult↗

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

Pancreatic resection versus peritoneal lavage in acute necrotizing pancreatitis. A prospective randomized trial.

Twenty-one patients with acute fulminant alcoholic pancreatitis were randomly allocated to either pancreatic resection group (11 patients) or nonoperative peritoneal lavage group (10 patients). Only patients under 50 years were included in the study to minimize the role of other severe disease. These patients represented the most severe cases of acute pancreatitis at our Department, constituting only 2% of all patients with acute pancreatitis during this period. The diagnosis was based on clinical symptoms and on signs indicating severely impaired systemic organ functions. All patients underwent contrast-enhanced computed tomography (CT), which showed contrast enhancement below 30 Hounsfield units. In the operated cases, the diagnosis of necrotizing pancreatitis was verified histologically. All patients with conservative treatment had dark brown fluid at peritoneal puncture. There was a difference (nonsignificant) in mortality (3/11 and 1/10, respectively), complication rate, or in the need of reoperations between the groups. Nonoperative peritoneal lavage was followed with shorter treatment at the intensive care unit (16.2 versus 25.9 days, respectively). The hospital stay also was significantly shorter in the nonoperative group (44.3 versus 56.1 days). The results indicate that intensive conservative treatment is justified as an initial therapy even in the most severe cases of acute pancreatitis.

Acute Disease↗

PubMed1991

Contrast media-induced renal tubular vacuolization. A light and electron microscopic study on rat kidneys.

The morphologic changes in healthy rat kidneys (n = 102) were studied 2 or 48 hours after intravenous injection of 1 or 3 g iodine (I)/kg of high-osmolality diatrizoate, low-osmolality iopromide and iohexol, or iso-osmolality iotrolan, as well as after 0.2 or 0.6 g/kg of the high-osmolality magnetic resonance contrast medium gadolinium DTPA. Physiologic saline was injected in controls. The kidneys were fixed by perfusion and the specimens were analyzed semiquantitatively by two independent observers blinded to the treatment. A statistically significant (P less than .01) cytoplasmic vacuolization was noticed in the proximal convoluted tubule cells 2 hours after injection of 3 g I/kg of diatrizoate or iopromide. Iohexol and iotrolan induced an even more significant (P less than .01) and longer-lasting vacuolization, but gadolinium DTPA did not produce lysosomal alterations. Although the vital cell organelles remained intact, reversible lysosomal alterations may represent the first structural signs of a threatening cellular injury.

Acute Kidney Injury↗

PubMed1991

Comparison of retrobulbar and periocular injections of lignocaine by computerised tomography.

Ten patients undergoing cataract surgery were given a local anaesthetic with lignocaine solution which was mixed with iohexol contrast medium. The location of the needle and the substance injected was determined by computerised tomography following retrobulbar or periocular anaesthesia. The retrobulbarly inserted needles were within the muscle cone, directed towards the optic foramen. The periocular needles were outside the muscle cone, tangentially along the orbital floor or pointing slightly upwards. After the retrobulbar injection the contrast medium was seen within the cone immediately after the injection and outside the cone as early as 3 minutes after the injection. With the periocular technique, however, diffusion of the anaesthetic in the opposite direction (that is, into the muscle cone) was rapid. The contrast medium was identified inside the muscle cone 2 minutes after the injection. Compression with an intraocular pressure reduction device after both of these techniques prevented exophthalmos. It is concluded that retrobulbar-like anaesthesia can also be induced by an appropriate periocular technique.

Adult↗

PubMed1991

Thyroid gland: US screening in a random adult population.

High-frequency ultrasound examination of the thyroid was performed in 253 subjects (130 women and 123 men; age range, 19-50 years) that were randomly selected from the population in an area of Finland where goiter is not endemic. Thyroid echo abnormalities were detected in 69 subjects (27.3%). Prevalence of abnormalities increased with age, and women showed more lesions than did men in each of the 3 decades. The abnormality was solitary in 39 subjects (57%), multiple in 15 (22%), and diffuse in 15 (22%). Of the 68 individual nodules, 48 (70%) were smaller than 1 cm in diameter. Anechoic rounded nodules 1-5 mm in diameter were found in 28 subjects. Fine-needle aspiration biopsy was performed in 30 subjects. Cytologic examination revealed no unequivocal malignancies. In eight subjects (3.2%) with a diffuse echo abnormality, cytologic evaluation indicated lymphocytic thyroiditis. It is concluded that the prevalence of small thyroid echo abnormalities in a randomly selected adult population is rather high, a fact that supports use of a conservative approach to these types of findings.

Adult↗

PubMed1991

Diagnostic evaluation and aggressive surgical approach in bleeding pseudoaneurysms associated with pancreatic pseudocysts.

Hemorrhage is an uncommon but serious complication of pancreatic pseudocysts. When gastrointestinal bleeding or intra-abdominal hemorrhage is associated with a pancreatic pseudocyst and the usual sources of bleeding are not detected by endoscopy, the rupture of a pseudoaneurysm inside the pseudocyst should be suspected. We present 13 cases, 11 associated with chronic and 2 with late complications after acute necrotizing pancreatitis. On the basis of sonographic findings, bleeding site was suspected in 8 of 11 patients (73%). Computed tomography (CT) was performed on 10, and bleeding was suspected in 8 (80%). The pseudoaneurysm itself was detected by CT in one and by ultrasonography in none. Visceral angiography was performed on five patients, and the pseudoaneurysm was evident in all. External drainage with arterial ligation was done as a primary operation in five patients; four of them later underwent pancreatic resection because of rebleeding. In eight cases pancreatic resection was the initial operation; none of these patients continued to bleed or needed reoperation because of the same pseudoaneurysm. There were no intraoperative deaths, but one patient died postoperatively. Aggressive diagnostic evaluation and surgical approach are associated with a reduction in mortality and morbidity in this serious complication of pancreatic pseudocysts.

Acute Disease↗

PubMed1991

Efficacy and complications of the Nd:YAG laser in partial nephrectomy: experimental study in piglets.

Twenty-four partial nephrectomies were performed in 18 piglets using either the combination Nd:YAG laser technique (contact and noncontact) or a steel scalpel. Additional haemostasis was attempted with ligatures. Blood loss, operation time, and number of ligatures were compared in the two treatment groups. Twelve piglets had a two-week follow-up. The mean blood loss with the laser was 72 +/- 10 g and 83 +/- 13 g with the steel scalpel (no significant difference). The resection time until complete haemostasis was 9.8 +/- 0.9 min with the laser and 14.3 +/- 1.3 min with the steel scalpel (p = 0.0076). The number of ligatures needed for complete haemostasis was 2.8 +/- 0.4 with the laser and 7.5 +/- 1.0 with the steel scalpel (p = 0.0051). Three piglets in the steel scalpel group developed urinomas. There were two perirenal abscesses, one in each group. In the steel scalpel group there was one intussusception. In conclusion, it seems that the combination Nd:YAG laser method offers no definitive advantage over the standard technique for partial nephrectomies in the pig.

Animals↗

PubMed1991

CT evaluation of acute pancreatitis: 8 years clinical experience and experimental evidence.

One hundred sixty eight patients with suspected serious pancreatitis were examined by dynamic CT. According to clinical data 103 of the patients had an oedematous pancreatitis (OP) and 65 a haemorrhagic-necrotizing pancreatitis (HP). Contrast enhancement (CE) of the pancreas was measured by dynamic CT during the first 24 hours after admission to the hospital. A control study was performed in 48 hours, if the finding on the primary CT was not definite or there was a discrepancy between CT and the clinical finding. Patients with HP showed significantly lower CE during the first minute after bolus injection of contrast material than patients with either normal pancreas or those who had OP. Only 4 out of 65 patients with HP showed normal (over 40 HU) and 8 out of 103 patients with OP showed low (less than 30 HU) CE. The method seems to be the most reliable method available to differentiate HP from OP. Before giving contrast material to the patients severe hypovolemia and respiratory distress should be excluded and treated.

Acute Disease↗