Cerebral hemodynamics in patients with moyamoya disease. A study of the epicerebral microcirculation by fluorescein angiography

Fluorescein angiography was performed in 12 hemispheres of eight young patients with moyamoya disease to study the epicerebral microcirculation. Regional circulation time and the time interval between carotid injection of the dye and first filling of the cortical arteries were various and prolonged in the most parts. There were nonfilling areas by carotid injection of the dye in six hemispheres. By venous injection, the dye appeared in all vessels of the exposed areas. Extravasation of the dye was seen in four hemispheres. The degree of these abnormalities of the epicerebral microcirculation was well correlated with the findings in conventional cerebral angiography.     

Effect of Hyperosmotic Solutions on Human Brain Tumour Vasculature

Summary  Reversible opening of the blood-brain barrier (BBB) has been used to increase delivery of chemotherapeutic agents into brain tumours, but it is complicated and requires general anaesthesia. Without affecting the normal BBB, and avoiding the complications of BBB modification by hyperosmotic solution, we tried an adequate minimal BBB disruption in brain tumours. Although the effect of BBB disruption on normal brain has been described, there are no reports of the effect of an impaired BBB on microcirculation. In this study, four patients underwent surgical resection of a glioblastoma multiforme (GM; n=1), astrocytoma (n=2), or metastatic brain tumour (n=1). Epicerebral microcirculation was observed in the operative field. Serial fluorescein microangiograms of the tumour and peritumoural area were obtained before and after BBB disruption was introduced intra-operatively by retrograde infusion of mannitol introducing a catheter via the temporal superficial artery back to the carotid bifurcation. On the initial microangiogram, staining by the fluorescein dye was observed in the GM and metastatic tumour but not in the astrocytoma; no extravasation of fluorescein dye was observed in the peritumoural areas. After BBB disruption, fluorescein perfusion increased and extravasation of fluorescein dye from the venules was observed in the GM and the metastatic tumour and in the peritumoural area of both lesions; BBB disruption started from venules in the peritumoural area without affecting the normal brain. However, such effects were not observed in the astrocytomas after BBB disruption nor in normal brain tissue in any patient. It appears that the integrity of the BBB is less stable in the peritumoural area of GM and metastatic brain tumours than it is in astrocytomas or normal brain. Osmotic BBB disruption may offer a method for achieving global delivery of therapeutic agents to brain tumours and peritumoural areas.     

Experimental study on the circulatory dynamics of the spinal cord by serial fluorescein angiography

The circulatory dynamics on the dorsal surface of the spinal cord were observed by serial fluorescein angiography . Fluorescein dye appeared in the posterior spinal artery and pial arterial plexus, although the direction of blood flow might be opposite and the time taken for fluorescein dye to enter the arteries was different for each. Fluorescein dye appeared in the veins after various periods, and the directions of flow of the dye were also variable and complicated. Laminar flow often was observed in veins of less than 200 microns in diameter. The regional circulation time was calculated to be 2.1 +/- 0.4 seconds. There was no extravasation.     

Experimental study on changes of the spinal-evoked potential and circulatory dynamics following spinal cord compression and decompression

In an attempt to elucidate the pathogenesis of spinal cord injury, the authors investigated the changes in spinal-evoked potential (SEP) and serial fluorescein angiography during compression and after decompression of the thoracolumbar cord in dogs. The degree of compression was correlated well with the changes in SEP during compression and after decompression. The findings of serial fluorescein angiography immediately after decompression indicated hyperemia and extravasation of the fluorescein dye, especially in the group weighted with 36 and 60 g. Poor filling of the arteries and veins with fluorescein dye, and prolongation of the regional circulation time were observed at between 30 and 120 minutes after decompression in the group weighted with 36 and 60 g. These findings suggest that secondary circulatory disturbance plays an important role in the pathogenesis of spinal cord injury. The relation between changes of SEP and the circulation are also discussed.     

Effects of argon, dye, and Nd:YAG lasers on epidermis, dermis, and venous vessels

The aim of the present study, which was performed at the dorsal aspects of the ears of guinea pigs, was to compare effects of different lasers on epidermis, dermis, and small venous vessels. Irradiations were performed with argon, dye, and Nd:YAG lasers. In the first series tissue repair processes were studied after argon laser application. Laser defects were excised after 1, 4, 8, and 14 days and were prepared for routine histological examination. The breadth of epidermal defect and extent of dermal coagulation and occlusion of vessels by thrombus formation were examined histologically. In a second series parameters of irradiation (ie, exposure time, laser power) of the three different lasers were changed systematically. Laser-induced morphological tissue changes could be best observed 24 hours after irradiation. Each of the lasers led to occlusion of vessels by thrombus formation and also coagulated epidermis and dermis. The extent of dermal and epidermal coagulation was less pronounced after dye laser application. Using short exposure times it was possible to reduce the extent of epidermal damage caused by argon and Nd:YAG lasers. Only 50-msec dye laser pulses led to intravascular thrombus formation without epidermal and dermal damage.     

The effect of neodymium yttrium aluminum garment laser on the cerebral blood vessel and blood brain barrier

The effect of the laser energy to the cerebral vascular reactivity and the blood brain barrier. A Nd:YAG laser with 20 watt impacts of 0.5, 1.0, 2.5 and 5.0 seconds duration time were irradiated through the cranial window made at the parietal regions of anesthetized adult cats. The disruption of the blood brain barrier was examined by checking the degree of the extravasation of Evans blue dye administrated in the vein. The cortical vessel reactivity was observed through the cranial window and evaluated using an intravital microscope and a videoangiometer. The extravasation of Evans blue dye was seen uniformly extending from the histologically changed area into the surrounding tissue in all experiments. The extent of the extravasation of dye was 1 to 1.5 mm larger than the extent of the histologically changed area produced by laser irradiation. Pial arteries in the area with histological changes dilated markedly and some of them lost their blood stream. Pial arteries in the area of Evans blue extravasation, but outside it histological changes also dilated markedly. Furthermore, pial arteries within a distance of 200 to 400 microns from the edge of the Evans blue extravasation area also dilated moderately. A statistical estimation showed that the degree of dilatation of arteries in the area outside the histological change improved significantly in the time course of five minutes.     

Antithrombotic Effects of Lidocaine and Related Compounds on Laser-Induced Microvascular Injury

The aim was to study whether topically applied local anaesthetics and related compounds exert an antithrombotic effect. The assay was carried out through vital microscopy of the microcirculation in the hamster cheek pouch model as injured by laser microbeam irradiation, essentially in order to record the differences in the incidence of thrombus formation between two main experimental and control series. The application of lidocaine hydrochloride was found to inhibit thrombus formation and also to restore the microcirculation after laser-induced injury. The other investigated compounds, mono-ethyl-glycinexylidide, tocainide and bupivacaine were found to be less active with regard to inhibition of thrombus formation and flow restitution effects. It is concluded that an antithrombotic effect may be attributed to lidocaine in particular.     

Subarachnoid and intracerebral hemorrhage associated with necrotizing angiitis due to methamphetamine abuse--an autopsy case.

The authors report an autopsy case of methamphetamine-related intracranial hemorrhage and vasculitis. A 22-year-old female was comatose after an intravenous injection of an unknown dose of methamphetamine. Computed tomographic scans demonstrated massive subarachnoid hemorrhage and hematoma in the corpus callosum. Cerebral angiography revealed nonfilling of bilateral intracranial carotid arteries and extravasation of contrast medium from the right pericallosal artery which was visualized retrogradely via the vertebral artery. Postmortem studies found cerebral edema, subarachnoid, intraventricular, and intracerebral hemorrhage, and intracranial vasculitis, but no aneurysm or arteriovenous malformation. Necrosis of vessel walls with destruction of the smooth muscle layer, but no leukocytotic infiltration of the vessel walls were observed in all major cerebral arteries. The hemorrhage probably resulted from medial necrosis in the large intracerebral vessels, and a sudden drug-induced rise in blood pressure.     

Assessment of the fluorescein dye test for prediction of skin flap viability in pigs

The visual fluorescein dye test for prediction of actual skin flap viability was evaluated in pigs. Two delayed random (4 X 10 cm) and arterial (4 X 20 cm) skin flaps were constructed on one flank of a pig, and four mirror-image skin flaps were raised acutely on the other flank of the same pig. Sodium fluorescein dye (15 mg/kg) was injected intravenously 1 and 18 hr after raising of flaps. The maximum length and area of dye stain in these flaps (N = 24) were assessed under Wood's lamp illumination, 15 min after dye injection. The actual maximum lengths and areas of skin survival of these flaps in the same pig were measured 7 days postoperatively. It was observed that visual fluorescein dye test performed 1 hr after surgery significantly (P less than 0.05) underestimated the maximum length and area of actual skin survival. On the other hand, when the fluorescein dye test was performed 18 hr postoperatively, the maximum length of dye stain and the maximum length of actual skin viability were highly correlated (r = 0.97, N = 24, P less than 0.01). Their mean values were similar (10.6 +/- 0.8 vs 10.8 +/- 0.7 cm, mean +/- SEM), and their mean coefficient of variation was 5.6 +/- 1.6%. Similarly, there was a high degree of correlation (r = 0.89, N = 24, P less than 0.01) between the maximum area of dye stain and actual skin flap viability. Their mean values were similar (68.3 +/- 4.5 vs 71.8 +/- 3.9%), and their mean coefficient of variation was 8.7 +/- 2.4%.(ABSTRACT TRUNCATED AT 250 WORDS)     

Fluorescein angiography for the detection of metastases of ovarian tumor in the abdominal cavity, a feasibility pilot

BACKGROUND AND OBJECTIVES: The growth and progression of ovarian tumor metastases at the peritoneal surfaces of the abdominal cavity are coupled with neovascularization. Newly formed tumor vessels show a more diffuse pattern and are more permeable for macromolecules than normal vessels. We investigated the possibility to detect (small) ovarian metastases in the abdominal cavity by means of fluorescein angiography. STUDY DESIGN/PATIENTS AND METHODS: Eighteen patients known with ovarian cancer or with suspicion for this disease received sodium fluorescein intravenously in different doses (0.4-1.6 ml of a 25% solution), whereafter fluorescence detection by laparoscope was carried out. The distribution pattern of fluorescein was gained from 0 to 120 min by pooling the data collected in different patients at various time intervals. RESULTS: Three phases could be discriminated, that is, rapid filling of blood vessels after administration of fluorescein, diffuse extravasation of fluorescein into surrounding tissues, and clearance of fluorescein from vessels and surrounding tissue. Differences in accumulation of fluorescein could be visualized only after 1 hour or more. Fluorescence imaging more then 60 minutes after administration of fluorescein did not give additional information compared to the inspection using white light, which was confirmed by histology. These observations were dose-independent. CONCLUSIONS: The concentration gradient differences of fluorescein between healthy and pathological tissue in the abdominal cavity are too small to indicate tumor neovascularization.     

Similarity of distributions of spinal c-Fos and plasma extravasation after acute chemical irritation of the bladder and the prostate

PURPOSE: Persistent pain in referred areas and voiding dysfunction are characteristic symptoms of chronic abacterial prostatitis. Since referred pain from visceral organs is considered a neurological event, it appeared reasonable to hypothesize that the persistent pain associated with prostatitis might also be explained by neural mechanisms. Neurogenic plasma extravasation and c-fos expression in the spinal cord, after chemical irritation of the rat prostate, was identified as a method to investigate the neurogenic aspect of prostatic inflammation. MATERIALS AND METHODS: The distribution of plasma extravasation using Evans blue dye was determined after chemical irritation of the prostate and bladder of the rat, and the distribution of dye extravasation was analyzed. c-fos expression within the spinal cord was determined immunocytochemically after chemical irritation of the prostate, bladder and superficial somatic region determined by the dye extravasation as a referred pain area (tail root). RESULTS: Chemical irritation of the prostate resulted in plasma extravasation in L5 to S2 dermatomes (primarily in L6 and S1). In rats receiving bladder irritation, the distribution of plasma extravasation showed a similar pattern to that observed in animals receiving prostatic irritation. Chemical irritation of the 3 structures resulted in expression of c-fos positive cells within the lumbosacral spinal cord. With each treatment the majority of c-fos positive cells were in the L6 and S1 segments. In all 3 groups the highest percentages of c-fos positive cells were observed in deeper laminae, including the dorsal commissure and sacral parasympathetic nucleus. CONCLUSIONS: Our results strongly suggest that referred pain status in inflammation of the bladder and prostate is neurogenically mediated. Based on these studies, there should be significant overlaps of nociceptive neurons within the spinal cord, which receive nociceptive inputs from pelvic soma and viscera.     

Neovascularization during venous thrombosis organization: a preliminary study.

PURPOSE: Thrombus organization after venous thromboembolism leading to recanalization occurs at a variable rate. The angiogenic chemokine interleukin-8 (IL-8) has been found in thrombus months after thrombus initiation. We hypothesize that thrombus organization involves neovascularization and leukocyte influx and that IL-8 administered at thrombus induction will promote thrombus organization. METHODS: A group of rats underwent inferior vena caval occlusive thrombosis. At thrombus induction and every 24 hours, the rats were administered IL-8 (1 microgram) or serum albumin. The rats were killed at either day 4, day 8, or day 12, and, at death, colloidal carbon was perfused via the heart. The inferior vena cava was isolated, measured, weighed, and formalin fixed. The sections were stained with anti-polymorphonuclear leukocyte antibody, the endothelial marker factor VIII-related antigen, and with hematoxylin and eosin. Thrombus neovascularization (colloidal carbon) with morphometric analysis was normalized to the total thrombus area. In addition, the rats underwent perfusion with fluorescein isothiocyanate dextran (molecular weight, 150,000) at death to correlate with colloidal carbon perfusion, and thrombus fluorescence was determined. RESULTS: Thrombus cellularity initially involved neutrophils, followed by monocytes. Significantly more neutrophils, monocytes, and cells that were defined as spindle shaped (fibroblasts and endothelial cells) were noted in the animals treated with IL-8. Neovascularization was significantly increased at day 4 in the animals treated with IL-8 versus the animals treated with serum albumin and was corroborated with a significant increase in thrombus fluorescein isothiocyanate dextran fluorescence at day 4 in the rats treated with IL-8. Colloidal carbon perfusion was noted within vascular channels without extravasation and colocalized with factor VIII-related antigen. CONCLUSION: This study shows that thrombus organization involves neovascularization and that IL-8 augments thrombus organization.     

Breast Necrosis Secondary to Vasopressor Extravasation: Management Using Indocyanine Green Angiography and Omental Flap Closure

Extravasation is a rare but serious complication of vasopressor administration. A 60‐year‐old female who underwent ascending and hemiarch repair of the aorta along with aortic valve replacement developed extensive right breast and chest wall necrosis after vasopressor extravasation from an internal jugular vein central line. The patient underwent a total mastectomy due to deep tissue necrosis detected by laser‐assisted indocyanine green dye angiography, and eventually required omental flap reconstruction to obtain adequate sternal coverage. This case represents a previously unreported complication of internal jugular central line extravasation of vasopressors with resultant breast and chest wall necrosis, and highlights the utility of the omentum in chest wall reconstruction.     

Selective occlusion of choroidal neovascularization by photodynamic therapy with a water-soluble photosensitizer, ATX-S10

BACKGROUND AND OBJECTIVE: To determine the optimal treatment parameters for selective occlusion of choroidal neovascularization (CNV) by photodynamic therapy (PDT) by using the photosensitizer ATX-S10 and a diode laser (wavelength = 670 nm). MATERIALS AND METHODS: Experimental CNV was induced in rat fundi by argon laser photocoagulation. The distribution of ATX-S10 in the chorioretina was analyzed by fluorescence microscopy, and the optimal treatment parameters for selective occlusion of CNV were investigated by changing the dosage and timing of laser irradiation. CNV closure and resulting damage of the surrounding tissue were documented by fluorescein angiography and light and electron microscopies. RESULTS: Fluorescence of ATX-S10 was observed to be localized in the vascular lumen of the retina and choroid within 5 min after dye injection and increased in intensity in CNV up to 2-6 h and decreased rapidly in normal tissue. Laser irradiation with radiant exposures of 7.4 J/cm2 applied immediately after dye injection or with 22.0 J/cm2 at 2-4 h later effectively occluded the induced CNV without causing significant damage to normal retinal capillaries and large choroidal vessels. CONCLUSIONS: PDT using ATX-S10 can selectively occlude CNV. ATX-S10 is a potentially useful photosensitizer for the treatment of CNV.     

Effects at the periphery of the laser lesion in human brain and its tumors after CO2, Nd:YAG, and CO2 high-peak pulsed radiation

The histological changes in various tissues irradiated with lasers are well known. Our own previous observations with the optical microscope confirm those already reported in the laser literature. If tissue is treated with various laser sources, the results are similar, with the characteristic three layers from the outside toward the inside of carbonization, coagulative necrosis, and edema. Otherwise, only the shapes and sizes of the lesions differ, with craters of different depths. In this paper, we report an ultrastructural study of the changes occurring in the periphery of the laser lesions in both normal human brain and neoplastic tissues (gliomas and meningiomas). Continuous-wave CO2 and Nd:YAG lasers were used at different exposure times and powers and the effects of high-peak pulsed CO2 laser radiation has also been investigated. The study, performed during neurosurgical procedures was mostly focused on microcirculation at 1.5-3 mm outside the area of coagulative necrosis, at the level of the edema zone. Only lesions of the blood brain barrier are produced in normal brain by CO2 radiation (power ranging from 40 to 80 W; exposure time from 3 to 10 seconds). The same results were achieved by Nd:YAG radiation of short duration (3 seconds) regardless of the power used (40 and 80 W). Long-duration Nd:YAG radiation (10 sec; power: 40-80 W) produces endoluminal phenomena leading to the complete occlusion of the capillaries. In neoplastic brain tissues, microcirculation does not seem to be impaired by CO2 radiation. More marked lesions are produced in tumors even after Nd:YAG short-time radiation. Endoluminal obliteration is observed in meningiomas and perivascular hemorrhage occurs in highly vascularized gliomas. According to these results, the risk of delayed post-operative hemorrhages, noticed in some patients with glioblastoma operated on by Nd:YAG lasers, suggests that residual tumor in the cavity should be treated by CO2 laser because of its minimal damage of microcirculation.     

Effect of age on cerebral venous circulation disturbances in the rat

OBJECT: Mild cerebral venous circulation disturbances (CVCDs) in aged patients are frequently known to cause unexpectedly severe postoperative complications in neurosurgical practice. The object of the present study was to determine whether there are age-related differences involved in vulnerability to CVCDs. METHODS: Thirty-eight male Wistar rats were used. A single cortical vein with a 100-microm diameter was occluded photochemically by using rose bengal dye and fiberoptic illumination in young (Group Y, 19 animals aged 10-14 weeks) and aged (Group A, seven animals aged 80-100 weeks) rats. Five young and seven aged animals served as sham-operated controls. Regional cerebral blood flow (rCBF) was determined from local CBF, which was measured at 25 (5 x 5) identical locations, with the occluded vein located central to the scanning field, by using a laser Doppler scanning technique every 15 minutes for 90 minutes after venous occlusion. The cerebral venous flow pattern was examined using fluorescence angiography until 90 minutes after occlusion. Histological specimens were examined 24 hours after occlusion. In Group Y, rCBF did not change significantly after venous occlusion. However, in Group A, rCBF decreased rapidly beginning 15 minutes after occlusion. Significant intergroup differences were observed 30, 60, and 90 minutes after occlusion. Venous flow arrest, which resulted in venous infarct, was observed on angiography 90 minutes after occlusion in two (10.5%) of 19 young and six (85.7%) of seven aged rats. The venous thrombus in Group A rats was significantly larger than that in Group Y rats 90 minutes after occlusion. Venous infarction was seen in all aged rats (100%) and in six young rats (31.6%); the infarct size, expressed as a percentage of the size of the ipsilateral hemisphere, was significantly larger in aged rats than in young rats. CONCLUSIONS: This study demonstrated an age-related increase in the rate and size of venous infarct following vein occlusion, suggesting that the greater vulnerability to CVCDs in the aged brain might be attributed to early and extensive hypoperfusion of circumscribed brain areas drained by the occluded vein. The larger thrombus formation in aged animals indicates that a shift in the thrombogenetic/thrombolytic equilibrium is responsible for the observed effect.     

Occlusion of the anterior cerebral artery after gamma knife irradiation in a rat

Summary The anterior cerebral artery of rats was irradiated at the level of the circle of Willis by Gamma Knife with a maximum dose of 25, 50, or 100 Gy. Occlusion of the anterior cerebral artery was observed in one rat which was followed for 20 months after irradiation of 100 Gy. Cerebral infarction was found at the midline-frontal region and the cingulate gyrus. Arterial wall thickening with fibrosis, splitting of the internal elastic membrane, luminal organized thrombus, and migration of smooth muscle cells into the thrombus were observed. In the anterior cerebral artery, thrombus formation seemed to occur after the endothelial injury and this may play a prominent role for occlusion. In small arteries, various changes were observed in the irradiated tissue. These included fibrosis and thrombus, thickened smooth muscle layer, lymphocytic infiltration, and thickening of vessel wall with fibrosis and fibrinous thrombosis with leakage of fibrin into the surrounding tissue after different doses of radiation and at different observation times. These changes were comparable to the ordinary vascular response to injury including healing vasculitis and arteriosclerosis.     

重症急性胰腺炎时胰腺血管造影的影像学表现及其临床意义

目的 探讨重症急性胰腺炎时胰腺血管造影的影像学表现及其临床意义。方法 对25例重症急性胰腺炎病人和20例胰腺无疾患志愿者,按Seidinger法将导管插入至胃十二指肠动脉行胰腺血管造影。结果 重症急性胰腺炎时胰腺血管造影的影像学表现为：(1)主干动脉／分支动脉的直径比增大;(2)“树枝状”结构的“树枝”数目明显减少;(3)“网络状”结构模糊;(4)胰腺“轮廓”的消失,或成片状、模糊不清。结论 (1)胰腺血管造影是一种比较客观、直观地反映胰腺血供情况的影像学手段;(2)重症急性胰腺炎时,胰腺血管造影有较明显的影像学异常表现;(3)其临床意义在于：对重症急性胰腺炎病情严重度有一定的评估作用;预测区域动脉灌注治疗的疗效;为临床应用改善胰腺微循环药物提供客观的影像学证据。     

An elderly patient with severe aortic stenosis and myocardial infarction with a huge mobile thrombus as complication in the left ventricle

An 86-year-old woman was admitted for emergency treatment of increasing dyspnea. Transthoracic echocardiography revealed decreased left ventricular systolic function with dyskinesis at the apex, and severe aortic stenosis. The apex of the left ventricle showed a huge mobile thrombus. Coronary angiography revealed total occlusion at the middle portion of the left anterior descending coronary artery. Emergency operation was successful, and a partially calcified thrombus was observed at the site of the old myocardial infarction area. In this case, myocardial infarction and elevated intraventricular pressure due to aortic stenosis likely contributed to the wall motion abnormality and thrombus formation.