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At least 865 records · Page 48Linked to original sources
PubMed2006

The blood vessel system in the periodontal ligament of the equine cheek teeth--part I: The spatial arrangement in layers.

Corrosion casts of blood vessels in the periodontium of cheek teeth from eight horses were observed three-dimensionally with a dissection microscope. Selected specimens were examined in a scanning electron microscope. Periodontal blood vessels communicated with those from the gingiva, the alveolar bone, and the apical region. In the upper jaw, there were anastomoses with the blood vessels of the mucosa of the maxillary sinus. The periodontal vascular system was organized in two or three layers. The peripheral layer was mainly composed of large venules, the inner one consisted of capillaries. In the intermediate layer, blood vessels were post-capillary venules. This layer was developed only in horses under 10 years of age. In all layers the vascular orientation was mainly occluso-apical, this was defined as the standard pattern. There were many variations displayed in different courses of certain blood vessels. The vascular organization is discussed with regard to the specialized functions of the periodontal ligament (PDL). The wide vessels of the outer layer are thought to play a mechanical role as part of a shock absorbing system. The capillaries of the inner layer meet nutritional requirements. The disappearance of the intermediate layer in horses older than 10 years is taken as an adaptation to the remodelling of the PDL. Modifications in the standard pattern of vascular arrangements are also interpreted as adaptations to life-long changes in the periodontal space. Anastomoses between the periodontal vasculature and the blood vessels of the maxillary sinus indicate that periodontal disease may be transferred into the sinus.

Animals↗
PubMed2005

Vessel maturation effects on tumour growth: validation of a computer model in implanted human ovarian carcinoma spheroids.

We analysed measurements of tumour growth, neovascular maturation and function in human epithelial ovarian carcinoma xenografts, studied noninvasively by magnetic resonance imaging. Results suggest that vascular maturation and mature and immature vessel regression occur continuously during tumour neovascularisation. Moreover, in these spheroids, a high tumour growth-rate is associated with monotonic changes in vessel density (VD) and with large proportions of mature blood vessels, whereas a lower tumour growth-rate is associated with fluctuating VD and lower proportions of mature vessels. These results corroborate a mathematical model for tumour dynamics, including vascular maturation and immature and mature vessel regression. The model predicts that rapid tumour growth may result from a high maturation-rate of neo-vasculatures, due to substantial mature VD in the microenvironment, while a slower tumour growth is an outcome of a lower background VD, leading to a lower vessel maturation-rate, larger proportion of immature vessels and, consequently, to regression-driven instabilities. The generality of these results for other tumour types should be validated.

Animals↗
PubMed2006

Improved vessel morphology measurements in contrast-enhanced multi-detector computed tomography coronary angiography with non-linear post-processing.

Multi-detector computed tomography (MDCT) permits detection of coronary plaque. However, noise and blurring impair accuracy and precision of plaque measurements. The aim of the study was to evaluate MDCT post-processing based on non-linear image deblurring and edge-preserving noise suppression for measurements of plaque size. Contrast-enhanced MDCT coronary angiography was performed in four subjects (mean age 55 +/- 5 years, mean heart rate 54 +/- 5 bpm) using a 16-slice scanner (Siemens Sensation 16, collimation 16 x 0.75 mm, gantry rotation 420 ms, tube voltage 120 kV, tube current 550 mAs, 80 mL of contrast). Intravascular ultrasound (IVUS; 40 MHz probe) was performed in one vessel in each patient and served as a reference standard. MDCT vessel cross-sectional images (1 mm thickness) were created perpendicular to centerline and aligned with corresponding IVUS images. MDCT images were processed using a deblurring and edge-preserving noise suppression algorithm. Then, three independent blinded observers segmented lumen and outer vessel boundaries in each modality to obtain vessel cross-sectional area and wall area in the unprocessed MDCT cross-sections, post-processed MDCT cross-sections and corresponding IVUS. The wall area measurement difference for unprocessed and post-processed MDCT images relative to IVUS was 0.4 +/- 3.8 mm2 and -0.2 +/- 2.2 mm2 (p < 0.05), respectively. Similarly, Bland-Altman analysis of vessel cross-sectional area from unprocessed and post-processed MDCT images relative to IVUS showed a measurement difference of 1.0 +/- 4.4 and 0.6 +/- 4.8 mm2, respectively. In conclusion, MDCT permitted accurate in vivo measurement of wall area and vessel cross-sectional area as compared to IVUS. Post-processing to reduce blurring and noise reduced variability of wall area measurements and reduced measurement bias for both wall area and vessel cross-sectional area.

Algorithms↗
PubMed2005

Cellular abnormalities of blood vessels as targets in cancer.

Tumor blood vessels have multiple structural and functional abnormalities. They are unusually dynamic, and naturally undergo sprouting, proliferation, remodeling or regression. The vessels are irregularly shaped, tortuous, and lack the normal hierarchical arrangement of arterioles, capillaries and venules. Endothelial cells in tumors have abnormalities in gene expression, require growth factors for survival and have defective barrier function to plasma proteins. Pericytes on tumor vessels are also abnormal. Aberrant endothelial cells and pericytes generate defective basement membrane. Angiogenesis inhibitors can stop the growth of tumor vessels, prune existing vessels and normalize surviving vessels. Loss of endothelial cells is not necessarily accompanied by simultaneous loss of pericytes and surrounding basement membrane, which together can then provide a scaffold for regrowth of tumor vessels. Rapid vascular regrowth reflects the ongoing drive for angiogenesis and bizarre microenvironment in tumors that promote vascular abnormalities and thereby create therapeutic targets.

Angiogenesis Inhibitors↗
PubMed2004

Myocytes of chorionic vessels from placentas with meconium-associated vascular necrosis exhibit apoptotic markers.

Meconium-associated vascular necrosis (MAVN) is a histological abnormality of human placental chorionic vessels that is associated with poor neonatal outcome. We tested the hypothesis that MAVN shows apoptosis in the walls of chorionic vessels. Archival placental specimens with MAVN (n = 5) were compared with specimens from uncomplicated pregnancies at term (n = 5) and from placentas with intense chorionic vasculitis associated with acute chorioamnionitis with (n = 5) or without (n = 5) a clinical history of meconium in the amniotic fluid. Sections from all placentas were processed by the TUNEL method, and 2 observers who were blinded to specimen diagnosis quantified the immunofluorescent TUNEL staining in both the amnion-facing and villous-facing walls of the larger chorionic vessels in each specimen. Compared with the other 3 groups, only the amnion-facing wall of chorionic vessels in MAVN showed a significantly greater number of apoptotic cells. This was verified by morphological criteria and caspase 3 staining. There were limited or no detectable TUNEL-stained cells in either the villous-facing walls of vessels in the MAVN specimens or in any of the vessels of the placentas from uncomplicated pregnancies. There was a negligible level of apoptosis in chorionic vessels of placentas with intense chorionic vasculitis, with or without meconium, despite the inflammatory response or presence of meconium. We conclude that apoptosis contributes to the pathophysiology of MAVN.

Apoptosis↗
PubMed2006

There is no relation between the fascicular and the endoneural blood vessel areas on the cervical vagus nerve of normotensive rats.

The aim of this study was to determine the existence of a relation between the fascicular area and total vessel area on the cervical vagus nerve of Wistar-Kyoto female rats. Animals aged 30, 180 or 360 days had their right vagus nerves prepared for epoxy resin embedding and light microscopy study. Semithin serial sections were studied every 100 microm of the longitudinal extension of the nerve. The fascicular area and the total endoneural vessel area were obtained for each nerve segment (proximal, middle and distal) and compared between segments and ages. The relation between fascicular area and endoneural vessel area was accessed by linear regression analysis and correlation coefficient calculations. No significant relationship between the two variables was detected in all nerves studied. This suggests that the entrance of blood vessels to the endoneural space is not accompanied by an increase in the fascicular area and this may have implications on the fiber density calculations since, in the presence of large vessels, this density can be underestimated if the vessel area is not discounted. The endoneural vessel area increased from proximal to distal in all groups but got smaller with ageing, suggesting that older animals may be more susceptible to nerve ischemia.

Aging↗
PubMed2006

Plaque development, vessel curvature, and wall shear stress in coronary arteries assessed by X-ray angiography and intravascular ultrasound.

The relationships among vascular geometry, hemodynamics, and plaque development in the coronary arteries are complex and not yet well understood. This paper reports a methodology for the quantitative analysis of in vivo coronary morphology and hemodynamics, with particular emphasis placed on the critical issues of image segmentation and the automated classification of disease severity. We were motivated by the observation that plaque more often developed at the inner curvature of a vessel, presumably due to the relatively lower wall shear stress at these locations. The presented studies are based on our validated methodology for the three-dimensional fusion of intravascular ultrasound (IVUS) and X-ray angiography, introducing a novel approach for IVUS segmentation that incorporates a robust, knowledge-based cost function and a fully optimal, three-dimensional segmentation algorithm. Our first study shows that circumferential plaque distribution depends on local vessel curvature in the majority of vessels. The second study analyzes the correlation between plaque distribution and wall shear stress in a set of 48 in vivo vessel segments. The results were conclusive for both studies, with a stronger correlation of circumferential plaque thickness with local curvature than with wall shear stress. The inverse relationship between local wall shear stress and plaque thickness was significantly more pronounced (p<0.025) in vessel cross sections exhibiting compensatory enlargement (positive remodeling) without luminal narrowing than when the full spectrum of disease severity was considered. The inverse relationship was no longer observed in vessels where less than 35% of vessel cross sections remained without luminal narrowing. The findings of this study confirm, in vivo, the hypothesis that relatively lower wall shear stress is associated with early plaque development.

Computer Simulation↗
PubMed2006

On the transendothelial passage of tumor cell from extravasal matrix into the lumen of absorbing lymphatic vessel.

The aim of the research is the study of ultrastructural characteristics of the absorbing lymphatic vessel and of tumor cell passage through the endothelial lymphatic wall in (a) subcutaneous xenografts of T84 colon adenocarcinoma and B16 melanoma cell lines in nude mice and (b) human colorectal cancer. It was found that the tumor-associated absorbing lymphatic (TAAL) vessel has the same ultrastructural characteristics as the absorbing lymphatic vessel in normal organs, and it is provided with an endothelial wall wholly lacking a continuous basement membrane, pores, fenestrations, and open junctions. The TAAL vessel is always missing in the studied tumor masses as far as the central stroma is concerned, whereas it is always present in the peripheral area of the tumor and in the peritumoral connective tissue. The factors of extravasal matrix that play an active role in migration process of invasive phenotype tumor (IPT) cell after its detachment from tumor mass, as well as the role of cytoplasmic protrusions (pseudopod-like) in lymphatic recognition, were considered. For the first time, this study demonstrated the transendothelial passage of IPT cell inside the TAAL vessel lumen, which takes place by means of the intraendothelial channel (approximately 1.8-2.1 mum in diameter and 6.8-7.2 microm in length). This channel is to be considered a transient morphological entity organized by TAAL vessel endothelium by means of still unidentified molecular mechanisms. Therefore, it appears to be ascertained that the intraendothelial channel represents a step forward in the knowledge of the drainage into lymphatic circulation of interstitial fluid and the answer to the lack of knowledge expressed till today by researchers concerning the modality of passage of the tumor cell through the endothelial wall of the TAAL vessel.

Animals↗
PubMed1989

Hemostasis in blood vessels after ligation.

The length of time required to achieve hemostasis after ligation of blood vessels with a diameter of 1.0 to 3.5 mm was studied. Canine limb vessels were ligated with stainless steel clips. These were removed at 48, 60, 72, 84, or 96 hours after ligation, and the degree of hemostasis was evaluated by observing the effect of varying amounts of trauma applied to the vessels. The vessels were first observed for 1 minute. In the second phase the vessels were stroked for 15 seconds and then observed for 1 minute. In the second phase the vessels were stroked for 15 seconds and then observed for any bleeding. An additional 15 seconds of stroking followed by observation completed the evaluation. All blood vessels achieved hemostasis after 96 hours of secure ligation despite the trauma. All ligating devices must provide secure ligation to achieve hemostasis for at least 96 hours. The presence of disease processes or medications interfering with clotting would necessitate a longer period of secure ligation to achieve hemostasis.

Animals↗
PubMed1990

Twin vessels in familial retinal cavernous hemangioma.

We investigated the presence of twin vessels in two patients and in four of their relatives at risk from one family with autosomal-dominant hereditary cavernous hemangioma of the retina associated with central nervous system involvement. Twin vessels were detected in four of the six patients examined. The proband had bilateral retinal vascular hamartomas with central nervous system involvement but no twin vessels. The proband's mother had vascular hamartomas of the retina and brain with twin vessels. In the other three family members, twin vessels were associated either with retinal cavernous hemangiomas (one patient) or with normal fundi (two patients). Because twin vessels may be an ocular manifestation of von Hippel-Lindau disease, their presence in one of our two patients and in the otherwise healthy three family members suggests that twin vessels may be associated with different retinal vascular hamartomas, including capillary and cavernous hemangiomas.

Adult↗
PubMed1961

Effects of the vessel wall on electromagnetic flow measurement.

The theory of the electromagnetic blood flow measuring technique is extended from the well known case (conductive liquid flowing through an insulating tube) to more realistic situations. First the conductivity of the vessel is taken into account, and the electric potentials in both liquid and vessel wall are calculated. The potential difference V between two points on the outside of the vessel and on an axis at right angles to both magnetic field B and the flow v is computed. The comparison is made with the classical flowmeter result V = 2Ba[UNK] (a = inner radius of vessel, [UNK] = mean flow velocity). For an average artery, with a ratio of inside diameter to outside diameter of 0.85, the error is found to be in the order of -7 per cent. The blood is assumed to be four times as conductive as the wall tissue. The induced potentials are then calculated in the liquid, in the vessel wall, and in a thin liquid conductive layer surrounding the artery. A film of serous fluid which is likely to exist between a blood vessel and the applied flowmeter sleeve creates an additional shunt. The voltage between the flowmeter electrodes deviates from the expected result by -10 to -15 per cent if the film thickness is 3 per cent of the outside radius of the tube. The evidence is therefore established that flowmeter cuffs should fit the blood vessels accurately to minimize errors.

Arteries↗
PubMed1998

Alterations in colonic mucosal vessels in patients with cirrhosis and noncirrhotic portal hypertension.

Changes in intestinal mucosal microvasculature as a cause of lower gastrointestinal hemorrhage in patients with portal hypertension have been well documented clinically, but the analogous histomorphological changes have not been well characterized. The goal of this study was to evaluate qualitative and quantitative changes in colonic mucosal vessels in patients with cirrhosis or clinically evident portal hypertension and to correlate these changes with endoscopic and clinical findings. Colon biopsy or resection specimen slides from 46 patients with biopsy-proven cirrhosis (44 patients) or noncirrhotic portal hypertension (two patients) were reviewed. Immunoperoxidase stain for CD34 antigen was used to facilitate visualization of mucosal vessels, and vessel diameter was measured with a micrometer. Patients with inflammatory bowel disease were excluded. Twenty-four normal colon biopsy specimens served as controls. Mucosal vessels were divided into superficial, intermediate, and deep layers. As a group, the cirrhotic patients had a significantly higher mean diameter of vessels in all three layers. Qualitatively, increased numbers of small vessels and prominent branching were noted, especially in the superficial and intermediate layers. Tortuous, thick-walled vessels, suggesting arterialization of venules, were present in some cases. Eleven patients had endoscopic findings suggestive of vascular abnormalities, including erythematous mucosal patches, red macules, and telangiectasias. Eighteen had esophageal varices, and five had portal gastropathy. Nineteen patients had gastrointestinal (GI) bleeding, localized to the lower GI tract in 11. These qualitative and quantitative findings suggest that colonic mucosal vascular lesions are common in portal hypertension and may represent a potential source of clinically significant lower GI hemorrhage in these patients.

Adult↗
PubMed1996

Can Tl-201 myocardial SPECT abnormalities in orthotopic heart recipients be explained by coronary vessel wall alterations assessed by intravascular ultrasound?

UNLABELLED: The aim of this study was to compare findings on coronary intravascular ultrasound and thallium-201 SPECT in patients following orthotopic heart transplantation. BACKGROUND: No data are available on whether pathological thallium scintigraphic findings in heart recipients are based on coronary vessel wall alterations identifiable by intravascular ultrasound. METHODS: 29 patients (mean age: 50.9 +/- 11.5 years; male n = 23) were investigated by means of intravascular ultrasound of selected coronary segments and thallium-201 myocardial SPECT. Patients were investigated 11.6 +/- 5.4 weeks post transplantation, a subgroup of 13 patients was re-investigated 70.2 +/- 18.4 weeks following transplantation. A total of 214 cross-sectional areas of the left coronary artery were examined using a 3.5 French intravascular ultrasound catheter to measure intimal index and the circumferential extension of a three-layer appearance of the vessel wall. Shortly after catheterisation, an ergometric stress-test was performed to examine all recipients by means of thallium-201 SPECT. In each patient, 20 segments of the left ventricle were evaluated using a score system of differentiate between persistent defects, redistribution, and reverse redistribution. A score was developed that measured the degree of inhomogeneity and severity of perfusion defects, respectively. Findings on scintigraphy were correlated to coronary intravascular ultrasound findings. RESULTS: At first investigation, mean intimal index of all evaluated coronary cross-sectional areas was 0.06 +/- 0.1. Sixty-four cross-sectional areas demonstrated a three-layer appearance of the vessel wall, mean circumferential extension was 72 +/- 122 degrees. Thallium scintigraphy demonstrated a total of 336 (40%) pathological left ventricular segments; 168 (20%) were regarded as permanent defects, 67 (8%) demonstrated redistribution and 101 (12%) showed reverse redistribution. The score of inhomogeneity was calculated as 5.8% +/- 2.6%. In the subgroup of patients at the follow-up study, the score was 6.4 +/- 2.8%. There was no correlation between intimal index and the score, nor could any correlation be confirmed between the score and the circumferential extension of a three-layer appearance of the vessel wall. At second investigation, no significant differences of intimal index (0.05 +/- 0.07) or circumferential extension of a three-layer appearance of the vessel wall (74 +/- 118 degrees) could be confirmed. The score was slightly, but significantly increased to 8.1 +/- 4.5% at the second investigation (P < 0.05). CONCLUSION: Early after orthotopic heart transplantation, pathologic thallium distribution patterns of the left ventricle could be observed. These pathological patterns did not correlate with the extent of diffuse coronary vessel wall alterations identifiable by intravascular ultrasound. After more than 1 year, the degree of scintigraphic abnormalities increased significantly, not accompanied by an increase of diffuse coronary vessel wall alterations.

Adult↗
PubMed1998

Developmental characteristics of vessel density in the human fetal and infant brains.

We demonstrated the developmental characteristics of vessel density in the human brain, using an antibody against CD31, which specifically reacts with endothelium. In the cerebral cortex and subcortical white matter, the vessel density was low at 16-28 weeks of gestation (GW), and then increased after 36 GW. In the deep white matter, the vessel density was high in the middle fetal period (16-24 GW), and then transiently decreased at 28-36 GW, and increasing after 39 GW. In the putamen, the vessel density was high at 20-21 GW, remained high throughout the fetal period, and then rapidly increased after birth. In the basis pontis, the number of vessels increased after 28 GW, and after 32 GW was greater than in the pontine tegmentum. These alterations in vessel density may correlate with the pathogenesis of perinatal brain injury. Thus, the transient decrease of vessel density in the deep white matter may predispose to periventricular leukomalacia in cerebral hypoperfusion. Similarly, the well-developed vascularity in the basis pontis may predispose its relatively immature neurons to neuron necrosis produced by free radical injury.

Aging↗
PubMed1999

An algorithm for noninvasive identification of angiographic three-vessel and/or left main coronary artery disease in symptomatic patients on the basis of cardiac risk and electron-beam computed tomographic calcium scores.

OBJECTIVES: We sought to model an algorithm for noninvasive identification of angiographically obstructive three-vessel and/or left main disease based on conventional cardiac risk assessment and site and extent of coronary calcium determined by electron-beam computed tomography (EBCT). BACKGROUND: Such an algorithm would greatly facilitate clinical triage in symptomatic patients with no previous diagnosis of coronary artery disease (CAD). METHODS: We examined 291 patients with suspected, but not previously diagnosed, CAD who underwent coronary angiography for clinical indications. Cardiac risk factors were determined as defined by the National Cholesterol Education Program. An EBCT scan was performed in all patients, and a coronary calcium score (Agatston method) was computed. Total per-patient calcium scores and separate scores for the major coronary arteries were generated. These scores were also analyzed for localization of coronary calcium in the more distal versus proximal tomographic sections. These parameters and the risk factors were considered for the model described in the following section. RESULTS: Sixty-eight patients (23%) had angiographic three-vessel and/or left main CAD. Multiple logistic regression analysis determined male sex, presence of diabetes and left anterior descending (LAD) and circumflex (LCx) coronary calcium scores, independent from more distal calcium localization, as independent predictors for identification of three-vessel and/or left main CAD. Based on this four variable model, a simple noninvasive index (NI) was constructed as the following: loge(LAD score) + log(e)(LCx score) + 2[if diabetic] + 3[if male]. Receiver operating characteristic curve analysis for this NI yielded an area under the curve of 0.88+/-0.03 (p < 0.0001) for separating patients with, versus without, angiographic three-vessel and/or left main CAD. Various NI cutpoints demonstrated sensitivities from 87-97% and specificities from 46-74%. The NI values >14 increased the probability of angiographic three-vessel and/or left main CAD from 23% (pretest) to 65-100% (posttest), and NI values <10 increased the probability of no three-vessel and/or left main CAD from 77% (pretest) to 95-100% (posttest). CONCLUSIONS: On the basis of a simple algorithm ("noninvasive index"), EBCT calcium scanning in conjunction with risk factor analysis can rule in or rule out angiographically severe disease, i.e., three-vessel and/or left main CAD, in symptomatic patients.

Algorithms↗
PubMed2001

Immunolocalization of occludin and claudin-1 to tight junctions in intact CNS vessels of mammalian retina.

The distributions of occludin and claudin-1, two tight junction-associated integral membrane proteins were investigated by immunohistochemical analysis of whole-mount preparations of the blood vessels in the myelinated streak of the rabbit retina. Light microscopy revealed that occludin and claudin-1 immunoreactivities were abundant along the interface of adjacent endothelial cells of all blood vessels. Electron microscopy revealed that both proteins were distributed in a regular pattern (at regular intervals of approximately 80 nm) along the length of tight junctions, probably in the regions of tight junction strands. No other structures or cell types expressed either of these two proteins in the myelinated streak. Whereas occludin immunoreactivity was concentrated only at the tight junction interface, claudin-1 immunoreactivity also extended into the cytoplasm of the endothelial cells, suggesting a different structural role for claudin-1 than for occludin at tight junctions. Retinal pigment epithelial cells expressed occludin around their entire circumference, consistent with the function of these cells as a barrier separating the retina from the leaky vessels of the choroid. Also consistent with the association of occludin expression with vessels that exhibit functional tight junctions, this protein was expressed at only a low level in, and showed an irregular distribution along, the vessels of the choroid, a vascular bed that lacks blood-barrier properties. Further, the distribution of occludin was examined during formation and remodelling of the rat retinal vasculature. Occludin expression was evident at the leading edge of vessel formation and was found on all vessels in both the inner and outer vascular plexus. Numerous vascular segments at the early stage of vascular formation and regression lost occludin expression. The biological significance of this transient loss of occludin expression in terms of barrier function remains to be elucidated.

Animals↗
PubMed2004

Tissue engineering of ovine aortic blood vessel substitutes using applied shear stress and enzymatically derived vascular smooth muscle cells.

Compared to native blood vessels, all clinically available blood vessel substitutes perform suboptimally. Numerous approaches to tissue engineer (TE) blood vessels have been pursued using different scaffold materials, cell types, and culture conditions. Several limitations however remain to be overcome prior to the potential application in the arterial system. This study aimed at tissue engineering viable ovine blood vessels suitable for implantation into the systemic circulation of sheep. In recent studies vascular smooth muscle cells (vSMC) were derived by an explant technique. However, in this study we show that homogenous populations of differentiated vSMC were only obtained by enzymatic dispersion as characterized by immunostaining for specific vSMC marker proteins. In contrast the explant method yielded predominantly less differentiated myofibroblast-like cells. Enzymatically derived vSMC were seeded onto P-4-HB scaffolds and incubated either in a pulsatile flow bioreactor or under static conditions. Dynamically cultured TE blood vessel substitutes showed confluent layered tissue formation and were completely water resistant. They displayed significantly increased ECM synthesis, DNA, and protein content as well as vSMC marker expression. Mechanical properties of bioreactor cultured TE blood vessels approached those of native aorta. In conclusion ovine, aortic blood vessel substitutes were successfully created using enzymatically derived vSMC, bioabsorbable scaffolds, and applied shear stress.

Animals↗
PubMed2005

The clinical study of congenital looped/coiled peripapillary retinal vessels.

PURPOSE: To present clinical manifestations of eyes with peculiar looped/coiled peripapillary retinal vessels. METHODS: Seven patients with looped/coiled retinal vessels on or near the optic disc were enrolled. All patients went through detailed ophthalmologic examinations and fluorescein angiography (FAG). RESULTS: There were two men and five women. Patients' age ranged from 15 to 71 years (mean: 39 years). The follow-up period ranged from 3 to 74 months (average: 27 months). One patient had bilateral involvement. Five of the seven patients noticed sudden onset of floaters in one eye. The colour fundus photography revealed looped/coiled retinal vessels on or near the optic disc, and most of the vessels were arteries. Accompanied retinal, preretinal, or vitreous haemorrhage was noted in all five patients who had sudden onset of floaters. Fluorescein angiography showed no leakage from the looped/coiled retinal vessels. No specific underlying diseases were noted in any patients. Follow-up examination revealed reabsorption of haemorrhage, and no change of the abnormal vessel patterns in any eyes. CONCLUSIONS: The peculiar fundus lesion of looped/coiled peripapillary retinal vessels is likely a benign congenital retinal vascular anomaly that does not progress. Floaters secondary to preretinal or vitreous haemorrhage is the most frequent complaint. The prognosis is excellent.

Adolescent↗