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PubMed1994

[Laser Doppler flowmetry for evaluation of nasal mucosa microcirculation].

The purpose of this study was to determine the blood flow within the human nasal mucose and whether it is changed in patients with chronic rhinitis. Using a laser Doppler flowmeter (He-Ne Laser equipment PF2 type), we measured the nasal mucosa blood flow (NMBF) in a group of healthy young subjects 108 (18-25 years) and three types of chronic rhinitis 89 (chronic rhinitis 15, allergic rhinitis 44, atrophic rhinitis 30). A Laser Doppler probe was placed on six different points of the nasal mucose membrane. The study data indicate that the average index of the NMBF of human are retentive steady and decreased obviously in three types chronic rhinitis. So it may be concluded that detection of NMBF is a useful method for evaluation of the therapy effect of chronic rhinitis.

Adolescent↗
PubMed1995

[Improvement of highly reproducible technique of four-vessel occlusion model and its study on metabolic changes of cerebral reperfusion in rats].

The four-vessel occlusion method introduced by Pulsinelli et al is widely used as an experimental model for reversible forebrain ischemia in rats. However, this model has a major problem in the difficulty assuring complete occlusion of the vertebral arteries by electrocauterization through the alar foramina of the first cervical vertebra. Anatomical basis of the vertebral artery suggested by Sugio et al indicates that the vertebral artery at the level of the second cervical vertebral is visible. In this study, we further developed highly reproducible model of reversible forebrain ischemia, which is modified four-vessel occlusion in rats. Male Wistar rats were subjected to four-vessel occlusion. Under microscope the visible vertebral arteries at the second vertebra could be easily electrocauterized and completely cut by microscissors to yield complete cessation of circulation of bilateral vertebral arteries without failure. After 24 hours, animals were subjected to 15, 30 and 45 minutes of forebrain ischemia by occluding both common carotid arteries with Sugita's temporary clips. 31P-magnetic resonance spectroscopy (31P-MRS) were obtained with a 6.3-T spectrometer to investigate sequential change of the in vivo brain energy metabolism. Our studies indicated that high energy phosphorus compounds were reduced in a few minutes after the induction of the forebrain ischemia, and they returned to the normal level after the recirculation. In addition, we monitored electroencephalogram (EEG) during the whole experimental period. The EEG showed a flat pattern after the induction of ischemia, and EEG recovered normal pattern within 12 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

Use of a low profile Doppler angioplasty guidewire to evaluate the effect of percutaneous coronary angioplasty on coronary artery flow velocity.

BACKGROUND: The intracoronary Doppler flow velocity measurement is widely used. The Doppler flow catheter, used in many studies, still cannot always measure distal portions of coronary artery stenosis. However, three years ago, a low profile Doppler angioplasty guide wire (0.018-inch) was started by apply for measurement of changes in proximal and distal flow velocity during coronary angioplasty. METHODS: Blood flow velocity and diastolic/systolic velocity ratio (DSVR) on both proximal and distal portions of the coronary artery were measured with a low profile Doppler angioplasty guide wire in 13 patients with stenosis of the left anterior descending artery (LAD) during coronary angioplasty. RESULTS: Non-significant improvement in maximal peak velocity was noted in the distal portion of the coronary artery immediately after angioplasty (before, 36 +/- 12 cm/s; after, 41 +/- 12 cm/s; p > 0.05); but significant improvement was found after removal of the balloon (from 41 +/- 12 cm/s to 49.5 +/- 15 cm/s, p < 0.01). Increases in proximal maximal peak velocity after angioplasty were less remarkable (before, 38.5 +/- 15 cm/s; after, 45 +/- 13 cm/s; p > 0.05), and there was a significant increase of DSVR on the distal portion of the left anterior descending artery after angioplasty (before, 2.18 +/- 0.51; after, 2.98 +/- 0.44; p < 0.05). However, there was no significant increase of DSVR on the proximal portion of LAD (before, 2.19 +/- 0.16; after, 2.44 +/- 0.1; p > 0.05). The coronary flow reserve ratio showed no significant increase on the distal portion of the LAD (before, 1.03 +/- 0.3; after, 1.02 +/- 0.3) and proximal portion of LAD (before, 1.05 +/- 0.2; after, 1.03 +/- 0.3). CONCLUSIONS: Increase in peak velocity and DSVR of the distal portion of the coronary artery after angioplasty was more significant after removal of the balloon catheter than as if it were assessed immediately, without removing the balloon catheter. No significant increase in flow velocity of the proximal portion of the coronary artery after angioplasty was observed. No significant increase of the coronary flow reserve of the distal and proximal portion of the coronary artery occurred after successful angioplasty.

Adult↗
PubMed1994

[Evaluation of the influence of placental localization on qualitative estimation of waveforms of blood flow velocity in uterine and arcuate arteries in third trimester physiologic pregnancy].

We presented in our study methods and results of blood flow measurements with Doppler ultrasound in uterine and arcuate arteries in relation to localization of placenta in physiological pregnancy. We performed examinations in 154 pregnant women with pregnancy age of 32-42 wk. On the basis of qualitative analysis of blood flow waveforms we discovered the difference in the blood flow in utero-placental compartment in relation to placental localization and we proved that this change takes place in uterine as well an in arcuate arteries.

Adult↗
PubMed1995

Ischemic conditioning of the rat stomach: implications for esophageal replacement with stomach.

BACKGROUND: Esophagectomy, with gastric pull up replacement, is not uncommonly complicated by leakage from the esophagogastrostomy anastomosis. Occult ischemia of the mobilized gastric fundus is a major etiologic factor in anastomotic leakage. OBJECTIVE: To test the hypothesis that tissue perfusion in a partially devascularized stomach will improve over time by a process of ischemic conditioning ("delay" phenomenon). EXPERIMENTAL DESIGN COLON: Laboratory study of partial gastric devascularization in rats. ANIMALS: Twenty rats. INTERVENTIONS: Partial gastric devascularization was achieved by ligation of the left gastric artery. MEASURES: Gastric perfusion was measured with a laser-Doppler flowmeter (in tissue perfusion units, TPU). Perfusion measurements were made at baseline, after vessel ligation, at 7 days, and at 14 days. RESULTS: Perfusion immediately after vessel ligation (23.8 +/- 6.0 TPU) was significantly lower than baseline gastric tissue perfusion (88.4 +/- 9.8 TPU) (p < 0.00001). After 7 days, tissue perfusion had increased (54.4 +/- 9.2 TPU), but it was significantly lower than baseline values (p < 0.00005). After 14 days, perfusion was increased (71.7 +/- 8.6 TPU) compared to 7 day measurements (p < 0.001), but it was still significantly lower than baseline gastric tissue perfusion (p < 0.002). Nevertheless, 14 day perfusion was 81% of baseline values. CONCLUSIONS: After partial devascularization, gastric perfusion steadily improves by a process of ischemic conditioning ("delay" phenomenon). The principle of ischemic conditioning may be clinically applicable to the gastric pull up operation.

Animals↗
PubMed1994

Effects of hypnotic suggestions on ultraviolet B radiation-induced erythema and skin blood flow.

Results from both animal and human studies have indicated that inflammatory skin reactions such as the flare response to histamine prick test involve a neurogenic regulatory component. It is still unknown to which degree inflammation induced by ultraviolet (UV) radiation may be mediated by the central nervous system. To investigate this, the effect of hypnotic suggestions to increase and decrease the response to UVB radiation on erythema and cutaneous blood flow was investigated in 10 highly hypnotizable subjects. The results showed a significant effect of hypnotic suggestions on cutaneous blood flow compared with the responses of a control group. For erythema no conclusive evidence was found. The results indicate the possibility of separate regulatory mechanisms behind central nervous system influence on UVB-induced erythema and skin blood flow respectively, and further investigations are needed.

Adult↗
PubMed1994

[Respiration-dependence of cutaneous laser Doppler flow motion].

The aim of this study was to show and to quantify the breath-dependency of cutaneous fluxmotion in the volar proximal forearm using a new computer-aided system. A meanflux-related index (MI) representing the intensity of the influence of respiration on fluxmotion was calculated. There was a good correlation between MI and the rate of respiration under spontaneous breathing: the lower the rate of respiration, the higher the value of MI. Prescribing a constant breathing rhythm amplifies this frequency-dependent effect. According to occurrence of low rates of respiration (< 12/min) also under physiological conditions the respiration should be simultaneously recorded while assessing fluxmotion.

Adolescent↗
PubMed1994

Toe systolic blood pressure after local cooling in primary Raynaud's phenomenon.

First toe systolic blood pressures (FTSBP) before and after first toe cooling were measured with the laser Doppler method in 17 normal women and 10 female patients with primary Raynaud's phenomenon (PRP). The room temperature was maintained at 26 degrees C. There was no significant difference in toe-arm systolic blood pressure ratio between the two groups. After toe cooling at 10 degrees C, the PRP group had a significantly greater reduction in FTSBP than the normal group. Measurement of FTSBP before and after toe cooling is a useful method for assessing Raynaud's phenomenon in the toes of patients with PRP.

Adult↗
PubMed1994

Influence of biological response modifiers: measurement of tumor blood flow and temperature.

Human recombinant interferon-alpha-2b (IFN) is known to inhibit growth of both normal and tumor cells and to stimulate immune effector cell function. We have previously shown that IFN and other biological response modifiers augment accumulation of radiolabeled antibodies in tumors. This investigation demonstrates that 30 min post i.m. administration of IFN significantly (p < 0.01) enhances tumor perfusion in tumor-bearing mice and persists for a much longer time than in normal tissue, which, in part, may contribute to the enhanced tumor uptake of radiolabeled monoclonal antibodies within 1.5 h of their administration. Histological examinations of tumors obtained from animals receiving IFN 72 h previously did not show changes in inflammatory cells. Our investigation shows that laser Doppler flowmetry and color Doppler imaging can provide an excellent means of measuring tumor perfusion changes in small living animals where radioactive tracers cannot be used.

Animals↗
PubMed1994

[Compression stockings in treatment of lower leg venous ulcer].

AIM: of the study was to evaluate the efficiency of medical compression stockings, which do not require special application techniques, compared with short stretch bandages for treating leg-ulcers. STUDY-DESIGN AND PATIENTS: Prospective trial on a total of 50 out-patients with leg-ulcers randomly allocated into two therapy-groups: 25 patients got firm compression bandages using short stretch material (Rosidal K), 25 patients were treated by medical compression stockings (Thrombo+Sigvaris 503). Due to the statistically significantly lower mean age and longer duration of the ulcers in the Sigvaris-group only restricted comparison of the treatment groups is possible. Local dressings in both groups consisted of a nonadherent, absorbing material (Vliwin) with an individually modelled rubber foam pad on top. The end-point was complete ulcer-healing, in a period of 3 months. METHODS: The following parameters were measured: area of ulceration, compression-pressure, tcPO2 and Laser-Doppler-Fluxmetry at the ulcer border before and after 3 minutes of arterial occlusion, venous volume and venous filling index by air plethysmography (APG) with and without compression. RESULTS: After 3 months 21 cases (84%) were healed in the Sigvaris-group and 13 (52)% in the Rosidal-group. This significant difference may be partly explained by the more favorable starting condition of the stocking-patients. However, one major advantage of stockings over short stretch bandages is the maintenance of an adequate pressure if they are not renewed for several days. CONCLUSION: Therapy of venous ulcers by medical compression stockings may be an effective approach for fit and cooperative patients.

Adult↗
PubMed1993

Differentiation of platelets from red cell fragments using laser technology: comparison between splenectomized and nonsplenectomized thalassemic patients.

Platelets from 59 beta-thalassemia/hemoglobin E (beta-thal/HbE) patients (19 were splenectomized) and 97 normal individuals were studied using laser and computer analysis. Fragmented red cells of similar platelet volume were differentiated from platelets using laser inspection of the intracellular hemoglobin of the fragmented red cell. The patients had increased platelet count than normal cases at p < 0.0001 (nonsplenectomized, mean +/- SE = 32.4 +/- 21.9; splenectomized, 617.5 +/- 64.2; normal, 264.7 +/- 6.4 x 10(3) cells/dl). Splenectomized patients had greater platelet counts than nonsplenectomized cases (p < 0.0001). Numbers of small red cells, probably red cell fragments, markedly increased in nonsplenectomized patients. Increased heterogeneity in platelet size was demonstrated in the patients of both groups. The nonsplenectomized patients had significantly higher mean platelet volume than normal (p < 0.02) and splenectomized cases (p < 0.01). Increased platelet number and heterogeneity in platelet population may involve in pulmonary thrombosis in splenectomized patients.

Adolescent↗
PubMed1994

Intraplaque hemorrhage of the carotid arteries: diagnosis by duplex scanning.

Eighty-three patients with intraplaque hemorrhage of the carotid arteries, explored by Duplex scanning, are reported; 36 among them were also studied by digital angiography and 28 were operated on. The echographic aspect suggesting the presence of an intraplaque hemorrhage is that of a hypo-anechogenic stria separating the intimal plaque from the media-adventitia complex. On the contrary, the angiographic findings are aspecific and unrelated to the presence of intramural blood clots. We think that duplex scanning is the investigation of choice in detecting intraplaque hemorrhage of the carotid arteries. The role of other radiological techniques, such as computed tomography of the neck and magnetic resonance, is also discussed.

Aged↗
PubMed1994

Changes in muscle and liver lactate concentrations after endotoxin infusion in rats.

The interstitial lactate concentration in rat skeletal muscle and liver was measured using a microdialysis method during the early stage of endotoxemia and during lactic acid infusion. The lactate concentration in the muscle and liver interstitium never exceeded the blood lactate concentration throughout the 180 min period after endotoxin administration. The present findings also showed that the muscle and liver interstitial lactate concentration gradually increased in endotoxin-infused animals compared to that in lactic-acid infused animals, although the blood lactate concentration in lactic acid-infused animals was the same as that in endotoxin-infused animals. These findings suggest that the skeletal muscle and liver may consume lactate in an endotoxemic condition. However, the capacity of lactate consumption in the skeletal muscle might gradually decrease after endotoxin administration, although that in liver might be well preserved.

Animals↗
PubMed1995

[Changes in blood flow and skin reaction following radiation therapy].

Skin blood flow (SBF) during radiation therapy was measured and compared with skin reaction to examine the relationship between skin reaction and blood flow. The SBF of 50 patients including 16 with head and neck (H&N) cancer, 13 with breast cancer and eight with lung cancer were analyzed. In the H&N patients, SBF was increased according to the treated dose, while in the breast cancer patients SBF was slightly increased at 10 Gy, and did not change up to 40 Gy. In the lung cancer patients SBF was not increased until 20 Gy, and thereafter increased moderately at 30 Gy. Among H&N, breast and lung cancer patients, the most severe skin reaction was observed at the earliest time in breast cancer patients, while blood flow was only slightly increased. This must have resulted in a relatively higher skin dose than the reference point dose in breast cancer patients. Therefore, differences in the relationship between SBF and skin reaction were observed among different types of cancer patients. However, in H&N cancer patients, SBF was increased as skin dose increased. Skin blood flow could be a good indicator by which to estimate skin reaction quantitatively when the daily skin dose is around 1.6 Gy.

Aged↗
PubMed1992

[Microcirculatory changes in mitral prolapse as an expression of a systemic change in the connective tissue].

Many authors hypothesize that mitral valve prolapse (MVP) can be, in most cases, only a clinical sign of a primitive and systemic disorder of the connective tissue, like in Marfan Syndrome (MS). In our previous works we supported the presence of morphological and functional alterations of the microcirculation in patients affected by MS. In order to characterize a possible common denominator between these pathologies we have studied the cutaneous microcirculation in a group of patients affected by MVP, divided into 2 groups: anatomic MVP (MVP) and MVP syndrome (MVPS). The morphologic parameters have been investigated by nailfold capillaroscopy while digital laser-Doppler was used to study skin flowmetry. The results have been compared with a control group. Capillaroscopic remarkers showed an architecturally disorganized microvasculature with aspects related to a reduced compactness of the microvasculature unit with a significatively higher score compared with controls (7.3 +/- 2.9 vs 3.6 +/- 1 p less than 0.0005). Laser-Doppler flowmetry showed a significatively reduced rest flow; ischemic test showed: spike time 48.9 +/- 36.9 vs 15.3 +/- 7.7 s (p less than 0.0005), hyperemic acme 6.6 +/- 2.7 vs 12.5 +/- 8.4 UP (p less than 0.002); % increase 32.1 +/- 20.2 vs 51.5 +/- 15.4 (p less than 0.002). Thermic test showed a significatively higher thermic acme 8.7 +/- 4.2 vs 12.6 +/- 9.11 UP (p less than 0.05). These results appeared to be correlated with stage pathology as it was observed a severe microvasculature disorders in MVPS. Therefore we suppose that a phenotypic continuum may exist between MS and MVP.

Adult↗
PubMed1982

Current status of noninvasive tests in the diagnosis of peripheral arterial disease.

In this review of the current status of the vascular laboratory, the major emphasis has been upon those tests that have become well-established and documented, including resting pressure, pulse volume measurements, velocity studies, and three stress measurements--exercise ankle pressure, postocclusive reactive hyperemia, and the toe pulse reappearance time. Additional technology that may have application to peripheral arterial disease includes photoplethysmography, transcutaneous oxygen tension, laser-Doppler velocimetry, fluorescein angiography, infrared thermography, and transcutaneous electromagnetic flowmetry. These techniques, which are currently in development and experimental trial, were not discussed but are likely to provide significant additional information. The future role of the vascular diagnostic laboratory in the area of peripheral arterial occlusive disease appears clear. It has already become a standard resource of the community hospital and tertiary referral center. Its functions will become more and more generally accepted with time as newly graduating physicians who have been exposed to this technology enter the practice of medicine. It should permit obtaining an evaluation of all patients at the expert level, aid in the education of all physicians concerned with peripheral arterial disease, and play an important part in guaranteeing a higher level of patient care than has heretofore been available.

Arterial Occlusive Diseases↗
PubMed1988

Partitional measurement of capillary and arteriovenous anastomotic blood flow in the human finger by laser-Doppler-flowmeter.

This study was made to see whether changes in blood flow through the capillaries and arteriovenous anastomoses (AVA's) of the human finger can be measured by noninvasive flowmetry. Total finger blood flow (FBF) was measured by venous occlusion plethysmography; blood flow was measured by a laser-Doppler flowmeter (ADVANCE, ALF-2100, Tokyo, Japan) using probes with optic fiber separations of 0.3 mm (LDF-0.3) and 0.7 mm (LDF-0.7). The maximum sensitivities for LDF-0.3 and LDF-0.7 were at depths of 0.8 and 1.2 mm from the tissue surface respectively. Two series of experiments were performed on separate days. In the first series the test hand was immersed in a water bath whose temperature (Tw) was 25 degrees C at an ambient temperature (Ta) of 25 degrees C. Tw was raised to 35 degrees C (local hand warming), which was then followed by an increase in Ta to 35 degrees C (whole body warming). FBF, LDF-0.3, and LDF-0.7 increased during these thermal stimulations. However, the relationship of FBF to LDF-0.3 showed two different regression lines. In contrast, the relationship of FBF to LDF-0.7 showed a single regression line. In the second series, with Ta at 35 degrees C, the test hand was immersed in a water bath at Tw 35 degrees C. Tw was then raised every 10 min by 2 degrees C steps from 35 to 41 degrees C. At Tw 39-41 degrees C, FBF and LDF-0.7 in the test hand were significantly decreased compared with those at Tw 35 degrees C.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗