Venous Plexus Research Articles

A Novel Direct Pathway of Dural Venous Outflow from the Basilar Venous Plexus via the Diploic Space of the Clivus

The internal jugular vein (IJV) is the pre-eminent outflow of the dural venous sinuses (DVS) in the supine position, while the vertebral venous plexus (VVP) dominates venous outflow in the upright position. Emissary veins can also be an accessory pathway for this venous egress. To our knowledge, alternative dural venous sinus directly drainage via the diploic space has not been previously reported in the literature. Ten fresh frozen adult cadavers underwent exposure of the basilar venous plexus. The entire plexus, still adhered to the underlying clivus, was removed with its underlying bone and submitted for histological examination following decalcification (Masson Trichrome, 5μm slices). All specimens were found to have direct communication between the basilar venous plexus and underlying diploic space of the clivus i.e., no intermediate clival emissary vein. These were concentrated near the midline and were more numerous over the clivus near the junction of the occipital and sphenoid bones. The endothelium of the venous sinus was continuous at the opening into the diploic space and these openings ranged in size from 500 to 750μm (mean 650μm). An improved understanding of the cerebral venous drainage can assist clinicians and surgeons in recognizing normal, pathologic, and variant anatomy in this region. Based on our study, direct venous sinus (DVS) to diploic space drainage offers an additional pathway for venous egress from the intracranium. Therefore, removal of the dura over the clivus during various skull base procedures might be associated with increased venous bleeding from the basilar venous plexus on its deep surface where it interfaces with the clivus.

Mesenchymal Stromal Cells Facilitate Tip Cell Fusion Downstream of BMP-Mediated Venous Angiogenesis-Brief Report.

The goal of this study was to identify and characterize cell-cell interactions that facilitate endothelial tip cell fusion downstream of BMP (bone morphogenic protein)-mediated venous plexus formation. High resolution and time-lapse imaging of transgenic reporter lines and loss-of-function studies were carried out to study the involvement of mesenchymal stromal cells during venous angiogenesis. BMP-responsive stromal cells facilitate timely and precise fusion of venous tip cells during developmental angiogenesis. Stromal cells are required for anastomosis of venous tip cells in the embryonic caudal hematopoietic tissue.

Metastatic melanoma extending along the inferior vena cava to its branches and venous plexus: a rare route metastasis characterized by [18F]FDG PET/CT.

Metastatic melanoma extending along the inferior vena cava to its branches and venous plexus: a rare route metastasis characterized by [18F]FDG PET/CT.

Spontaneous uterine venous plexus complicated with ovarian rupture in the third trimester of pregnancy: a case report

BackgroundSpontaneous uterine venous rupture combined with ovarian rupture in late pregnancy is extremely rare. It often has an insidious onset and atypical symptoms, develops rapidly, and is easily misdiagnosed. Wewould like to discuss and share this case of spontaneous uterine venous plexus combined with ovarian rupture in the third trimester of pregnancy with colleagues.Case presentationA pregnant woman, G1P0 at 33+4 weeks of gestation,was admitted to the hospital due to threatened preterm labour on March 3, 2022. After admission, she was treated with tocolytic inhibitors and foetal lung maturation agents. The patient's symptoms did not improve during the treatment. After many examinations, tests, discussions, a diagnosis, and a caesarean section, the patient was finally diagnosed with atypical pregnancy complicated by spontaneous uterine venous plexus and ovarian rupture.ConclusionsSpontaneous rupture of the uterine venous plexus combined with ovarian rupture in late pregnancy is an occult and easily misdiagnosed condition, and the consequences are serious. Clinical attention should be given to the disease and prevention attempted to avoid adverse pregnancy outcomes.

Pelvic pain and venous congestion revisited: examining relationship between chronic pelvic pain and uterine venous size and blood flow.

To investigate the relationship between increased uterine venous plexus diameter and chronic pelvic pain in women attending a gynecology clinic. This was a retrospective study of patients attending a tertiary university hospital in London, UK. Women presenting to the gynecology clinic undergoing transvaginal ultrasound examination were recruited into the study. The largest trunk of the uterine venous plexus was measured on each side. Blood flow within the uterine veins was categorized into continuous or interrupted flow and evaluated using color and spectral Doppler ultrasound during normal respiration and on Valsalva maneuver to demonstrate the presence of venous reflux. The largest uterine vein diameter and its blood flow were used for the analysis. The main variables of interest were chronic pelvic pain, uterine vein diameter and type of blood flow. We included 1500 women in the study, of whom 584 (38.9% (95% CI, 36.5-41.5%)) reported chronic pelvic pain. Dysmenorrhea was the most common type of pelvic pain. Age (P < 0.001), menopausal status (P = 0.02), varicose veins (P = 0.01), adenomyosis (P < 0.001) and endometriosis (P < 0.001) were found to be independently associated with the occurrence of pain on multiple logistic regression analysis. There was no difference in uterine vein diameter between women with and those without pain (P = 0.10). Neither uterine vein diameter (P = 0.47) nor type of blood flow (P = 0.07) was significantly associated with the occurrence of pelvic pain on multiple logistic regression. Our findings show that uterine vein diameter is not associated with pelvic pain. However, we found other important clinical and demographic factors that are associated with chronic pelvic pain. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Sinus pericranii in the setting of a posterior fossa pilocytic astrocytoma: illustrative case.

Sinus pericranii (SP) is a rare vascular anomaly, with an uncertain etiology. Often discovered as superficial lesions, they can be primary or secondary in nature. Herein, we report a rare case of SP in the setting of a large posterior fossa pilocytic astrocytoma associated with a significant venous network. A 12-year-old male presented with acute clinical deterioration in extremis with a 2-month history of lethargy and headaches. Outside plain computed tomography imaging revealed a large posterior fossa cystic lesion, probably a tumor, with severe hydrocephalus. There was also a midline small skull defect at the opisthocranion, without visible vascular anomalies. An external ventricular drain was placed with rapid recovery. Contrast imaging revealed a large midline SP emanating from occipital bone with a large intraosseous, and subcutaneous venous plexus in the midline draining inferiorly into venous plexus around the craniocervical junction. A posterior fossa craniotomy without contrast imaging could have resulted in catastrophic hemorrhage. A small modified off-center craniotomy provided access to the tumor with a gross total excision. SP is a rare but significant phenomenon. Its presence does not necessarily preclude resection of underlying tumors, provided that a careful preoperative assessment of the venous anomaly is undertaken.

Portal Vein Variations, Clinical Correlation, and Embryological Explanation: A Review Article.

Portal vein(PV) is a large vein that collects blood from the abdominal part of gall bladder, pancreas, alimentary tract, and spleen and transports to the liver. One of the parts of the extraembryonic venous system, the vitelline veins, is where PV starts.In about five weeks of gestation, a venous plexus is formed, and variations in this plexus lead to portal variance.Thejunction of superior mesenteric and splenic veins is typically where the vein begins to network. There are five types of branching patterns of the right PV: conventional branching, trifurcation branching, early branching, separate segment 7 branching, and separate segment 6 branching.To perform pancreatic, duodenal, and liver surgeries, knowledge of variations in PV formation is important.For surgical and interventional operations to be accurate, it is crucial to understand the architecture of the PV and its anomalies. As distinct regions of the brain connect with one another, portal architecture is frequently observed in imaging investigations. Portal hypertension is characterized as an increase in blood pressure in the portal venous system (PVS) in the context of severe liver disease, such as cirrhosis. Non-invasive methods for examining the anatomy and anomalies of the PV include ultrasound, computed tomography (CT), and magnetic resonance (MR). There are many abnormalities of PVS that have been discussed in the articles such as Congenital PV Absence; PV Branches Congenitally Grow in Structure; Hypoplasia, Atresia, and Stenosis of the PV; and Portosystemic Shunts.

Atypical Varices Originating From the Round Ligament Venous Plexus

Atypical Varices Originating From the Round Ligament Venous Plexus

Pure spinal intraosseous arteriovenous fistula: A case report.

Spinal osseous arteriovenous fistula (AVF) is a rare disease with a characteristic angioarchitecture involving an intraosseous venous pouch (VP) of the vertebral body where the feeders are converging. Using spinal angiography alone, it is difficult to distinguish spinal osseous AVF from classical spinal epidural AVF (EDAVF) with fistulas in the epidural VP and bone erosion because both subtypes have an angiographically similar dilated VP appearance. Thus, spinal osseous AVF may be often misdiagnosed as spinal EDAVF. With advancing imaging techniques, it would be possible to determine the exact location of the fistula. Here, we present the case of a 37-year-old woman with a pure spinal thoracic osseous AVF and radiculopathy. She was diagnosed with spinal intraosseous AVF using high-resolution three-dimensional rotational angiography (3D-RA). The fistula was located in the Th1 lateral mass with a VP where multiple osseous feeders were converging. There was paravertebral venous drainage without intradural venous drainage. Transvenous embolization with Onyx and coils was performed through the azygos vein to the lateral epidural venous plexus, resulting in complete obliteration. This case suggests that 3D-RA reconstructed images are essential for accurate diagnosis and successful treatment of this condition. It is important to occlude only intraosseous VPs by accurate subtype diagnosis. Transvenous embolization is a treatment option for spinal intraosseous AVF with paravertebral epidural venous drainage.

Left Distal Transradial Approach for the Treatment of a Sacral Extradural Arteriovenous Fistula: A Technical Note and Literature Review

Sacral extradural arteriovenous fistula (SEAVF) is relatively rare, and its etiology is unknown. They are mostly fed by the lateral sacral artery (LSA). For endovascular treatment, both the stability of the guiding catheter and accessibility of the microcatheter to the fistula, distal to the LSA are required for sufficient embolization of the fistulous point. Cannulation of these vessels requires either crossover at the aortic bifurcation or retrograde cannulation using the transfemoral approach. However, atherosclerotic femoral and tortuous aortoiliac vessels can make the procedure technically difficult. Although the right transradial approach (TRA) can reduce this difficulty by straightening the access route, a potential risk remains for cerebral embolism because it passes the aortic arch. Herein, we present a case of successful embolization of a SEAVF using a left distal TRA. We report a case of a 47-year-old man with SEAVF treated with embolization using a left distal TRA. Lumbar spinal angiography showed a SEAVF with an intradural vein through the epidural venous plexus fed by the left LSA. A 6-French guiding sheath was cannulated into the internal iliac artery via the descending aorta using the left distal TRA. A microcatheter could be advanced into the extradural venous plexus over the fistula point from the intermediate catheter placed at the LSA. Embolization with coils and n-butyl cyanoacrylate was successfully performed. The SEAVF completely disappeared on neuroimaging, and the patient gradually recovered. Left distal TRA could be a useful, safe, and less invasive option for the embolization of SEAVF, especially for patients with high-risk factors for aortogenic embolism or puncture site complications.

Noninvasive diagnosis of liver fibrosis in schistosomiasis japonica: Opportunities and challenges

Noninvasive diagnosis of liver fibrosis in schistosomiasis japonica: Opportunities and challenges

Peripheral microcirculation alteration as cause of postero-superior rotator cuff tear: the possible indirect contribution of nailfold capillaroscopy.

Most of the recent literature regarding rotator cuff tear etiology identifies in peripheral microcirculation disorders the probable main cause of tissue degeneration, and consequently of tendon rupture. Nailfold capillaroscopy is a practical and inexpensive diagnostic technique used to evaluate the health status of the peripheral microcirculation and, recently, its use has found other indications in addition to that of diagnosing connective tissue diseases and Raynaud's phenomenon. We verified the possible indirect contribution of nailfold capillaroscopy in the identification of peripheral microcirculation disturbances in a group of patients with rotator cuff tear and whether these possible alterations could be related to rotator cuff tear size. A case control study was performed. 100 patients [(56M-44F; mean age(SD): 60.46 (5.46)] with different sized postero-superior cuff tears and 100 healthy controls [(38M:62F mean age (SD):60.40(6.34)] were submitted to capillaroscopic exam. The following parameters were examined: capillary morphology and density; avascular areas; visibility of the sub-papillary venous plexus; enlarged and giant capillaries; ectasias and microaneurysms; neo-angiogenesis; hemosiderin deposits; pericapillary edema; capillary blood flow. Severe exclusion criteria were applied. Statistical analysis was performed. Visibility of SPVP (p<0.001), pericapillary edema (p<0.001), capillary blood flow (p<0.001), ectasias and microaneurysms (p<0.001) and neo-angiogenesis (p = 0.04) were significantly associated with presence of RCT. Our results contribute to support the hypothesis that microcirculation disorder has a relevant role on the genesis of cuff degeneration and, consequently, of tendon rupture. However, these alterations do not seem to be related to rotator cuff tear size.

Minimally invasive modification of the Goel-Harms atlantoaxial fusion technique: a case series and illustrative guide.

The Goel-Harms atlantoaxial screw fixation technique for the treatment of atlantoaxial instability and unstable odontoid fractures is reliable and reproducible for a variety of anatomies. The drawbacks of the technique are the potential for significant bleeding from the C2 nerve root venous plexus and the risks associated with posterior midline exposure and retraction, such as pain and wound complications. The authors developed a minimally invasive surgical (MIS) modification of the Goel-Harms technique using intra-articular grafting to facilitate placement of percutaneous lateral mass and pars screws with extended tabs for minimally invasive subfascial rod placement. The objective of this study was to present the authors' first series of 5 patients undergoing minimally invasive modification in comparison with 51 patients undergoing open atlantoaxial fusion. A retrospectiveanalysis of patient comorbid conditions, blood loss, length of surgery, and length of stay was performed on patients undergoing Goel-Harms instrumented fusion (GHIF) for unstable odontoid fractures performed between 2016 and 2021. Patients undergoing the minimally invasive procedure showed significantly less blood loss than those undergoing the open atlantoaxial fusion procedure, with a median blood loss of 30 ml compared with 150 ml using the open technique (p < 0.01). The patients showed no significant differences in length of stay (2 days for MIS vs 4 days for open atlantoaxial fusion, p = 0.25). There were no significant differences in length of surgery for MIS, but a possible trend toward increased operative duration (234 vs 151 minutes, p = 0.112). In this small pilot study, it was shown that MIS-GHIF can be performed with decreased blood loss in atlantoaxial instability and odontoid fractures. This technique may allow for greater and safer application of the procedure in the elderly and infirm.

Hangover headache and its behavioral changes in rats.

The present study aims to establish and evaluate a rat model for hangover headaches caused by alcoholic drinks. Chronic migraine (CM) model rats were divided into 3 groups, and intragastrically administered alcoholic drinks (sample A, B, or C) to simulate hangover headache attacks. The withdrawal threshold for the hind paw/face and the thermal latency of hind paw withdrawal were detected after 24 hr. Serum was collected from the periorbital venous plexus of rats in each group, and enzymatic immunoassays were used to determine the serum levels of calcitonin gene-related peptide (CGRP), substance P (SP), and nitric oxide (NO). Compared with the control group, the mechanical hind paw pain threshold was significantly lower in rats administered Samples A and B after 24 hr; however, no significant difference was observed across groups for the thermal pain threshold. The mechanical threshold for periorbital pain was only significantly reduced in rats administered Sample A. Immunoassays further indicated that serum levels of SP in the group administered Sample A were significantly higher than those in the control group; the serum levels of NO and CGRP were significantly higher in the group of rats receiving Sample B. We successfully developed an effective and safe rat model for investigating alcohol drink induced hangover headaches. This model could be used to investigate the mechanisms associated with hangover headaches for the development of novel and promising candidates for the future treatment or prophylaxis of hangover headaches.

Abstract Number ‐ 91: A Case of Complex Giant Neck Arteriovenous Malformation Treated with Endovascular Embolization

Introduction Arteriovenous malformations (AVM) of the head and neck are vascular malformations composed of a cluster of connecting arteries and veins that form a central nidus without an intervening capillary network1. They make up 1.5% of vascular malformations and more than 90% of AVMs are located intracranially1. Extracranial AVMs are predominantly located in the head and neck and can manifest with pain, ulcerations, fatal hemorrhage, airway compromise, and cosmetic aberrations1,2. Methods We present a case of a 21 year old female with a medical history of multiple suspected neck hemangiomas status post microsurgical and laser resections, with a surrounding port wine stain, who presented to the hospital with growth of one of her posterior neck hemangiomas during and after pregnancy. In the postpartum period she reported increasing neck pain and persistent bleeding from the site. Initially, she was hemodynamically stable and her neurologic exam did not show any focal deficits. She underwent computed tomography angiogram of her neck which showed an extensive dorsal neck AVM with multiple arterial supplies frombranches of the bilateral subclavian, vertebral, and external carotid arteries.Her lesion continued to bleed with a precipitous drop in hemoglobin requiring blood transfusions. Subsequently, she underwent urgentpercutaneousN‐butyl‐2‐cyanoacrylate (n‐BCA) embolizationand endovascular onyx embolization of a left thyrocervical trunk branch.The procedure was completed without complications. Months later, she developed skin exfoliation and underwent successful elective embolization involving vertebral artery branches. This, to reduce profuse venous shunting in the paravertebral venous plexus, avoiding long term spinal cord injury. Results The management of complex head and neck AVMs is both challenging and complex. They may pose significant bleeding risk and can become infiltrative within surrounding tissue3. AVMs may be classified as either focal or diffuse. Focal lesions may be curable with resection, whereas diffuse lesions pose a significant challenge, with relapse in 90% of cases3. Head and neck AVMs require expert management and a multidisciplinary approach. The team may consist of neurosurgery, neuro‐endovascular,plastic surgery, and dermatology services. Treatment options include medical management, surgical resection, endovascular and percutaneous embolization. Percutaenous n‐BCA embolization is employed to prevent hemorrhage during surgical resection, or stabilization in acute hemorrhage4,5. This holds especially true when an endovascular approach is difficult; typically due to tortuous vasculature5. Treatment may require a staged target approach, with endovascular or percutaneous embolization prior to surgical excision. Conclusions This case highlights the complexities of AVM management and the multidisciplinary approach necessary, to provide optimal care. In this case, we believe that pregnancy could have contributed to the overall change in aggressive nature of the AVM. The patient underwent emergent percutaneous and endovascular embolization to prevent life threatening hemorrhage followed by palliative embolization to avoid long term cervical spinal cord injury due to venous hypertension.

The sphenopalatine vein: anatomical study of a rarely described structure.

Although in counterpart, the sphenopalatine artery (SPA), has been well described in the medical literature, the sphenopalatine vein (SPV) has received scant attention. Therefore, the present anatomical study was performed. Additionally, we discuss the variations, embryology, and clinical significance of the SPV. Adult cadaveric specimens underwent dissection of the SPV. In addition, some specimens were submitted for histological analysis of this structure. The SPV was found to drain from the sphenoidal sinus and nasal septum. Small tributaries traveled through the nasal septum with the posterior septal branches of the SPA and nasopalatine nerve. The SPA and SPV were found to travel through the sphenopalatine foramen and another tributary was found to perforate the medial plate of the pterygoid process and to connect to the pterygoid venous plexus which traveled lateral to the medial plate of the pterygoid process. The vein traveled through the posterior part of the lateral wall of the nasal cavity with the posterior lateral nasal branches of the SPA and the lateral superior posterior nasal branches of the maxillary nerve. To our knowledge, this is the first anatomical study on the SPV in humans. Data on the SPV provides an improved anatomical understanding of the vascular network of the nasal cavity. Developing a more complete picture of the nasal cavity and its venous supply might help surgeons and clinicians better manage clinical entities such as posterior epistaxis, cavernous sinus infections, and perform endoscopic surgery with fewer complications.

Classification and Management Considerations for Intraosseous Dural Arteriovenous Fistulae.

Intraosseous dural arteriovenous fistulas (IODAVFs) are rare DAVFs that communicate with marrow. Given their infrequency, common nomenclature is nonexistent. Patients may present with benign symptoms, such as tinnitus, or venous hypertension symptoms including hemorrhage depending on the venous outflow pattern. To describe all available cases of IODAVF in the literature, in addition to our cases, to better define presentation, and treatment outcomes. To advance a classification system to develop common language for these lesions for clinicians and researchers. Neurointerventional procedure logs at 2 high-volume neurovascular centers were reviewed for all cases of IODAVFs, as was the English-based literature available in PubMed. The angioarchitecture, symptoms, management, and demographics were reviewed and summarized. Four institutional cases were identified, 2 of which had shunting within the marrow (clival or petrous), with venous drainage toward the heart. One case involved the dorsum sella with drainage into the superior petrosal sinus with reflux into the anterior and posterior spinal venous plexuses, and one involved the left petroclival junction, resulting in communication with the cavernous sinus with retrograde drainage into the superior ophthalmic veins. Two patients were managed by observation, one was treated with radiosurgery and one with microsurgical skeletonization. Twenty additional cases from the literature are summarized. IODAVFs of the cerebrocranial vasculature may present incidentally, with tinnitus, or with symptoms related to mass effect or venous hypertension. We propose a classification which accounts for drainage patterns. Further study is needed for these rare lesions.

Varicocele: a Case Report

Varicocele is a condition with abnormality in growth and dilatation of veins that drains blood from the testicle, the scrotal venous pampiniform plexus. Although commonly painless, varicocele is the most prevalent cause that resulted in low count of sperm, poor sperm morphology, abnormal analysis of semen, and reduced sperm motility.

Applying a homogeneous pressure distribution to the upper vertebral endplate: Validation of a new loading system, pilot application to human vertebral bodies, and finite element predictions of DIC measured displacements and strains

Image-based personalized Finite Element Models (pFEM) could detect alterations in physiological deformation of human vertebral bodies, but their accuracy has been seldom reported. Meaningful validation experiments should allow vertebral endplate deformability and ensure well-controlled boundary conditions. This study aimed to (i) validate a new loading system to apply a homogeneous pressure on the vertebral endplate during vertebral body compression regardless of endplate deformation; (ii) perform a pilot study on human vertebral bodies measuring surface displacements and strains with Digital Image Correlation (DIC); (iii) determine the accuracy of pFEM of the vertebral bodies.Homogeneous pressure application was achieved by pressurizing a fluid silicone encased in a rubber silicone film acting on the cranial endplate. The loading system was validated by comparing DIC-measured longitudinal strains and lower-end contact pressures, measured on three homogeneous pseudovertebrae of constant transversal section at 2.0 kN, against theoretically calculated values. Longitudinal strains and contact pressures were rather homogeneous, and their mean values close to theoretical calculations (5% underestimation).DIC measurements of surface longitudinal and circumferential displacements and strains were obtained on three human vertebral bodies at 2.0 kN. Complete displacement and strain maps were achieved for anterolateral aspects with random errors ≤0.2 μm and ≤30 μstrain, respectively. Venous plexus and double curvatures limited the completeness and accuracy of DIC data in posterior aspects.pFEM of vertebral bodies, including cortical bone mapping, were built from computed tomography images. In anterolateral aspects, pFEM accuracy of the three vertebrae was: (i) comparable to literature in terms of longitudinal displacements (R2>0.8); (ii) extended to circumferential displacements (pooled data: R2>0.9) and longitudinal strains (zero median error, 95% error: <27%). Circumferential strains were overestimated (median error: 39%).The new methods presented may permit to study how physiological and pathologic conditions influence the ability of vertebral endplates/bodies to sustain loads.

Endoderm-derived islet1-expressing cells differentiate into endothelial cells to function as the vascular HSPC niche in zebrafish.

Endothelial cells (ECs) line blood vessels and serve as a niche for hematopoietic stem and progenitor cells (HSPCs). Recent data point to tissue-specific EC specialization as well as heterogeneity; however, it remains unclear how ECs acquire these properties. Here, by combining live-imaging-based lineage-tracing and single-cell transcriptomics in zebrafish embryos, we identify an unexpected origin for part of the vascular HSPC niche. We find that islet1 (isl1)-expressing cells are the progenitors of the venous ECs that constitute the majority of the HSPC niche. These isl1-expressing cells surprisingly originate from the endoderm and differentiate into ECs in a process dependent on Bmp-Smad signaling and subsequently requiring npas4l (cloche) function. Single-cell RNA sequencing analyses show that isl1-derived ECs express a set of genes that reflect their distinct origin. This study demonstrates that endothelial specialization in the HSPC niche is determined at least in part by the origin of the ECs.