Biomedical subjects
Publications and source records attributed to F I Todua.
Magnetic resonance angiography showed that blood flow in the aortic arch during protodiastole is separated into the opposite flows, which are temporarily arrested at the certain sites creating the flat front of the flow. The protodiastolic antegrade peak acceleration 6-fold surpasses the systolic one. Due to adhesion, the high gradient pressure forces can damage the vascular wall.
The aim of the work was to assess extra- and intracranial venous hemodynamics in patients with circulatory disorder-induced encephalopathy (DE). Altogether 114 DE patients were examined. There were 46 women and 68 men aged 43 to 78 years (mean age 59.6+/-12.5 years). As dependent on the clinical manifestations the patients were distributed into groups: stage 1 DE was present in 36 patients, stage 2 DE in 47>> and stage 3 DE was identified in 31 patients. 82.78% of the examined had arterial hypertension (AH), the mean standing of which accounted for 9.7+/-7.2 years. The control group accrued 36 practically normal persons aged 36 to 62 years (mean age 47.6+/-11.3 years). All the patients were provided standard neurologic examination, magnetic resonance tomography (MRT) of the brain with venography of the brachiocephalic veins and venous sinuses of the brain, Color Doppler Imaging of the extracranial vessels, and transcranial Doppler. The patients complained primarily of headache, dizziness, instability and staggering on walking, memory and work fitness decrease, and irritability. Atherosclerotic plaques which were primarily homogeneous (types IV and V according to the classification by Geroulakos et al., 1993) were identified in the carotid arteries in 76 (62%) patients. In 48 (42%) patients, stenoses were bilateral. Hemodynamically significant (>50%) stenoses were present in 42 (34%) persons. In most cases, the patients showed dilatation of the jugular veins and a mean reduction of the flow intensity to 14+/-8.1 cm/s as compared to the control group (20.6+/-11.3 cm/s). The tendency toward flow intensity lowering associated with its phasic nature disorder was particularly well-defined in patients with stage 3 DE and a long-term history of AH. On examination of the parameters of cerebral venous circulation the patients with stage 1 DE tended to the rise of the linear flow velocity (LFV) in the basal veins of Rozenthal and in the direct sinus. However, no significant changes in the PI parameters were recorded. In the patient group with stages 2 and 3 DE, there was an appreciable rise of the LFV in the deep veins in the presence of a remarkable PI lowering (the flow velocity in the vein of Rozenthal 21.8+/-7.2 cm/s in stage 2 DE, and 24.4+/-7.2 cm/s in stage 1 DE). In 87 (79%) cases, MRT revealed the signs of diffuse ischemic lesion of the brain. Fifty-five (48%) patients were diagnosed to have leukoarayos whereas in 48 (42%) cases, there were identified multiple lacunar infarctions, primarily of the deep cerebral segments. Ten (8%) patients demonstrated type 1 Arnold-Chiari abnormalities -- hypoplasia of the large cerebral cistern and 4 patients had porto-cerebellar atrophy (megacysterna magna). Analysis of the MRV revealed, in the majority of cases (in 67 or 59%), developmental abnormality of the drainage system of the brain. Thus, 42 (37%) patients were diagnosed to have hypoplasia of one of the transverse sinuses (of the right one in 23 cases and of the left one in 19 cases); 17 (15%) persons had aplasia of the transverse sinus. Eight patients showed hypoplasia of the sigmoid sinuses (of the right one in 5 cases and of the left one in 3 cases). In all the cases of developmental abnormalities of the venous sinuses, there was a compensatory dilatation of the contralateral sinus and in some cases, there were visualized the upper and lower sinuses, the identification of which in health is difficult. So, atherosclerosis of AH-induced lesion of the brachiocephalic arteries interferes with the action of the physiological "arteriovenous pump" thereby provoking venous congestion. Progression of the process is associated with depletion of the compensatory adaptive potentialities of the collateral venous outflow which (especially in concomitant developmental abnormality in the region of the posterior cranial fossa and venous sinuses) favours aggravation of venous circulatory distress, the rise of the CSF pulse pressure and the emergence of benign intracranial hypertension and hydrocephalus followed by cerebral atrophy.
The aim of the work was to examine the degree of carotid stenosis, the structure of atherosclerotic plaques, and the predominance of the main vascular risk factors in patients with multiple lacunar and comparatively large "non-lacunar" cerebral infarctions. A study WAS made of the data on 110 patients (mean age 62.5 years) with multiple cerebral infarctions revealed by MRT and with stenoses of the internal carotid artery (ICA) of varying degrees of severity. Minor lacunar infarctions (LI) were present in 62 cases whereas comparatively large "non-lacunar" infarctions (NLI) in 48 cases. All the patients underwent standard neurologic examination, laboratory analyses, MRT of the brain with angiography (MRA) of the extra-intrecrania1 vessels, transcranial Doppler (TCD), and examination of the heart for revealing the cardioembolic nature of cerebral infarctions. Among patients with both LI and NLI, arterial hypertension was the most frequently occurring risk factor in 53 (85%) and 35 (73%) patients respectively. In the study groups, there were no appreciable differences in the incidence of high hematocrit, hyperfibrinogenemia, tobacco-smoking, and diabetes mellitus. Patients with NLI demonstrated hypercholesterolemia, CAD and atherosclerosis of the peripheral vessels significantly more often (p<0.05). In the patient group with NLI, hemodynamically significant stenoses of the ICA were predominant: in 18 (37.5%) patients, they were moderate, in 12 (25%) critical, and 7 (14.6%) patients had occlusions whereas in LI, the portion of critical stenoses and ICA occlusions was cooperatively low - in 11 (17.7%) and in 5 (8.1%) patients respectively. Both groups showed the thickening of the complex of the medial CCA layer. Ultrasonopraphy of the vessels has revealed that in patients with NLI and LI, there predominated potentially embologenic plaques, namely in 69% and in 53% of cases, respectively. Our investigations allow to assume that arterial hypertension is the most frequently occurring risk factor of cerebral infarction (both minor lacunar and large "non-lacunar"). Factors such as CAD, hypercholesterolemia, DM, hemorheological disorders, end tobacco-smoking are likely to have an unfavorable impact on both general and cerebral hemodynamics as well as on the microcirculatory bed whereby being on the whole important risk factors of cerebral infarction. Hemodynamically significant stenoses, especially critical ones, occlusions, and embologenic plaques of the ICA are pathogenetically closely linked with the development of "non-lacunar" cerebral infarctions. At the same time they, under certain conditions, may become the cause of multiple lacunar cerebral infarctions.
AIM: To elucidate relationship between presence of atherogenic risk factors (dyslipidemia, hypertension, smoking, etc.) and common carotid artery intima-media thickness. MATERIAL AND METHODS: Color duplex carotid artery scanning and determination of blood lipids, lipo- and apolipoproteins were carried out in 160 patients aged 34-73 (mean 57.4+/-8.2) years. RESULTS: Dyslipidemia, hypertension (diastolic blood pressure > or = 95 mm Hg), smoking and intima-media thickness > 1 mm were present in 57, 49, 54 and 65% of patients, respectively. Intima-media thickness increased with age and in the presence of hypercholesterolemia, hypertension and smoking. Significant (p<0.05) correlations existed between intima-media thickness and levels of total cholesterol (r=0.512), triglycerides (r=0.411), apolipoprotein B (r=0.497), high density lipoprotein cholesterol (r=-0.404), apolipoprotein-A1 (r=-0.386), duration of hypertension (r=0.488). CONCLUSION: Ultrasound study of intima-media thickness allowed to assess harmful effect of various atherogenic risk factors (mechanical - hypertension, biochemical - dyslipidemia, toxic - smoking) on the state of arterial wall.
Explore the source record for details and available documents.
In the past five years, 16 adults (10 females, age 25-61 years, mean 48) with giant cavernous hemangioma of the liver measuring 15-31 cm (mean-19) underwent surgery in a single Institution. Diagnosis was made with the help of multimodal investigations- ultrasound (US), computed tomography (CT), hepatic angiography, hepatic scintigraphy and fine needle biopsy. Ultrasound and CT had sensitivities of 69% and 82% respectively. Fourteen had preoperative selective hepatic artery embolization to study its effect on operative blood loss. Indication for surgery in all cases was a large abdominal mass with varying severity of pain. In addition, 5 had hemetological and/or coagulation abnormalities, hemobilia in 1 and pyrexia in 1. Seven left lobectomies, 3 left lateral segmentectomies, 2 right lobectomies, 2 right trisegmentectomies and 4 non-anatomical resections of 1 to 3 segments were performed. Postoperative complications developed in 25% with no operative mortality. Preoperative selective hepatic artery embolization helped to decrease the operative hemorrhage in 13 (mean blood loss- 1146 ml). In two cases severe bleeding required use of Cell-saver and massive donor blood transfusion. Our results suggest use of preoperative selective hepatic artery embolization and Cell-saver as an adjunct to the liver resection for these vascular tumors.
In patients suffering from nonspecific aortoarteritis associated with impairment of the common carotid arteries, cerebral blood flow is compensated for at the expense of an increase of the volumetric blood flow in the vertebral arteries. During the first three years since the onset of the first disease symptoms, the blood content in the basin of the internal carotid arteries is reduced. Brain strokes occur most frequently within that period. They mostly develop without any preceding transitory ischemic attacks. The origin of neurological symptomatology depends to a considerable measure on the condition of the anterior and posterior communicating arteries.
Explore the source record for details and available documents.
The case of a patient treated for multiple cholangiogenic liver abscess due to residual biliary stone after acute cholecystitis is reported. The multiple liver cyst was cured by percutaneous transhepatic double drainage controlled by CT as well as puncture and aimed local systemic antibiotic treatment. The residual gallbladder stone was removed by endoscopic papillotomy. A similar case has not been reported so far.
Thirty-three patients with pyogenic liver abscess were treated by percutaneous transhepatic puncture or permanent drainage between the period of 1, January 1985 and 31, December 1990. The closed puncture or drainage resulted in the complete recovery of 26 patients (26/33 = 78.8%). Surgical intervention was made 6 +/- 5 days following closed drainage in 7 cases (7/33 = 21.2%). After percutaneous intervention complications ensued in four patients (4/33 = 12.1%). One patient died (1/33 = 3%). Solitary abscess occurred in 24, while multiple in 9 patients. Based on the authors' experiences, they consider the closed percutaneous puncture, or drainage guided by computed tomography--provided that proper shills and facilities are available--them does not enable in all cases the precise preoperative diagnosis even despite its richness of detail. In order to reduce uncertainties and to establish an accurate diagnosis, Herbert et al., McCorrcel et al. and Perera et al. proposed three criteria to be met before establishing the diagnosis of pyogenic liver abscess. According to the authors the conditions for accepting these criteria can be summarized as follows: 1. On the US examination of the liver, echo-free or echo-poor regions can be seen with increased background echoes. CT verifies an inhomogeneous, circumscribed or irregular-shaped, blurred focus of finely deformed contours being hypodense in contrast with the environment. On administration of contrast medium, the change is surrounded by a hyperdense border, and other causes for the above change can be excluded. 2. Verification of the presence of pus (by percutaneous puncture or surgery) from the liver biopsy. 3. The negative result of serological tests characteristic of amoebic infection. CT and US examinations have opened up new vistas not only in establishing diagnosis but also in the management of the disease. The closed percutaneous and effective method in the management of liver abscesses.
Method of dermal adrenal hyperfunctional suppression under CT-control in Itsenko-Cushing disease has been offered. Studies in the laboratory and in the clinic have revealed that this method is a method of choice in treatment of mild and middle forms of Itsenko-Cushing disease.
Employment of computer-aided tomography and ultrasonic scanning in 74 patients with liver abscesses helped rapidly detect the condition and identify its type. The sensitivity of ultrasonic scanning in the diagnosis of liver abscesses has made up 90.77 percent, specificity 86.44 percent, in computer-aided tomography these values have been the same and made up 97.96 percent. Closed transcutaneous interventions monitored by computer-aided tomography and ultrasonic scanning in these patients helped reduce the number of complications from 48.78 to 27.27 percent, mortality rates from 29.27 to 3.03 percent, hospitalization periods by 13.21 days, i. e. by 20.6 percent, as against the patients treated by traditional surgical methods.
Possibilities of noninvasive radial diagnostics were studied in examination of 27 patients with dissecting aneurysms of the aorta. Classical X-ray examinations of chest organs have diagnosed aorta wall dissection in 2 of 24 patients. In 19 patients the diagnosis of aorta dissection was suspected. The ultrasound examination gave correct diagnosis in 3 of 4 patients examined. The non-contrast computed tomography has revealed dissecting aneurysms in 8 of 24 patients, an investigation with the intravenous injection of the contrast substance--in 13 of 15 patients. The diagnosis was based upon the detection of 2 canals of the aorta with the dissected intima between them, thrombosis of the false aorta canal and accumulation of the liquid in the pleura and pericardium cavity. When planning operative procedures it becomes necessary to perform aortography.
The paper is concerned with analysis of the results of X-ray investigation of 45 patients with aneurysms of the distal part of the arch and descending part of the thoracic aorta. Errors were made in 16 of 35 patients (35.6%) before admittance to hospital. X-ray investigation helped to establish correct diagnosis of aneurysm of the aorta in 42 of 45 patients (93.3%) on the basis of the detection of intense additional shadow formation in left pulmonary field, inseparable from the aortic shadow. The use of a new method of ultrasound diagnosis--duplex scanning--made it possible to establish the presence of aneurysm and to determine its sizes as well as to visualize the relation of the left subclavicular artery to aneurysm in 17 of 21 patients. CT-semiotics of aneurysms of the descending part of the thoracic aorta consisted in its dilatation over 3.5 cm, wall calcification, thrombosis of the cavity and change of the adjacent structures. Basing on the analysis of these signs correct diagnosis was established in 34 of 35 examinees (97.1%).
The aspects of surgical tactics in management of dissecting aneurysms of the ascending aorta are analysed in relation to the disease etiology, the anatomical pattern of the aortic root, presence of attending aortic insufficiency, and dissection extension. Based on the experience of 32 operations (March 1979--February 1988), it is concluded that the abnormal type must be the best criterion for choosing the surgical technique. In dissecting aneurysms due to aortic wall degeneration, Bentall-De Bono and Cabrol's modifications are preferable. In dissecting aneurysms of atherosclerotic origin, the boundary of the proximal extension of dissection should be taken into account. When the dissection extends into the aortic root, the operation using a valve-containing conduit with reimplantation of the ostia of the coronary arteries is feasible. If the aortic root is not involved, isolated prosthesis of the ascending aorta or separate prosthesis of the aortic valve and ascending aorta may be performed depending on the presence of aortic failure.
Renal functional and structural studies were performed in 46 patients with arterial hypertension: out of them 12 had hypertensive disease, 13, chronic pyelonephritis, 21, a hypertensive type of chronic glomerulonephritis. In each case, the clinical diagnosis was evidenced by one of the invasive techniques. Dynamic computed tomography was conducted by the original methods; the findings were analyzed by taking into account time-density curves which made it possible to gain an insight into the status of blood flow and filtration in each individual kidney. Computed tomography and dynamic computed tomography revealed that hypertensive disease was characterized-by normal volume and thickness of the renal cortical layer and symmetric time-density curves, whereas a hypertensive type of chronic glomerulonephritis featured lower renal cortical layer thickness, reduced renal volume, symmetrically decrease amplitudes of the first and second peaks of the time-density curve, chronic pyelonephritis showed asymmetric time-density diagrams due to the lower density areas in the afflicted kidney.
Computed tomography (CT) of the brain was employed in 40 patients with systemic lupus erythematosus (SLE). Clinical cerebral pathology was obvious in 30 and absent in 10 patients. By CT cerebral symptoms were divided of 4 groups. Clinical symptom complexes of CNS defects and SLE were reflected on definite CT images, e. g. digital capillaritis, marked livedo. Raynaud's syndrome, disseminated erythematous skin lesions correlated with CT-shown focal damage to the brain. CT picture of enlarged subarachnoid space, ventricles and basal cisterns can be observed in SLE patients without neurological symptoms. This indicated likely subclinical cerebral affection.
Explore the source record for details and available documents.