Posterior Vein Research Articles

Distribution and Morphologic Characteristics of Choroidal Vortex Veins in Pachychoroid Disease.

This study aimed to elucidate the distribution and morphological features of choroidal vortex veins in pachychoroid disease (PCD). Retrospective observational study. Patients with PCD included from January 2022 to June 2023. We conducted a retrospective cross-sectional analysis using wide-field indocyanine green angiography (WF-ICGA) to assess choroidal vortex veins in PCD patients, categorizing them based on location (equatorial/posterior) and morphology (absent, incomplete, complete, complete with ampulla). The incidence of different location and morphology of vortex veins in PCD. A total of 190 eyes from 99 PCD patients were examined. Notably, only 8.9% (17/190) of eyes had posterior vortex veins. We identified 1620 vortex veins, predominantly equatorial (99%, 1603/1620). Morphologically, the most common type was incomplete (61.9%), followed by complete (19.5%), absent (11.1%), and complete with ampulla (7.5%). The distribution of these veins varied, with the inferotemporal quadrant showing the highest prevalence at 26.9%, followed by the superonasal (26.1%), superotemporal (24.3%), and inferonasal (22.7%) quadrants. The median number of vortex veins per eye was 8, with a range from 5 to 15. This study highlights that posterior vortex veins are less frequent in PCD eyes, with incomplete veins being the most prevalent. These findings provide important clinical evidence for understanding the distribution and morphologic characteristics of choroidal vortex veins in PCD, contributing to our knowledge of the pathophysiological mechanisms underlying this condition.

Enhancing Surgical Guidance: Deep Learning-Based Liver Vessel Segmentation in Real-Time Ultrasound Video Frames.

In the field of surgical medicine, the planning and execution of liver resection procedures present formidable challenges, primarily attributable to the intricate and highly individualized nature of liver vascular anatomy. In the current surgical milieu, intraoperative ultrasonography (IOUS) has become indispensable; however, traditional 2D ultrasound imaging's interpretability is hindered by noise and speckle artifacts. Accurate identification of critical structures for preservation during hepatectomy requires advanced surgical skills. An AI-based model that can help detect and recognize vessels including the inferior vena cava (IVC); the right (RHV), middle (MHV), and left (LVH) hepatic veins; the portal vein (PV) and its major first and second order branches the left portal vein (LPV), right portal vein (RPV), and right anterior (RAPV) and posterior (RPPV) portal veins, for real-time IOUS navigation can be of immense value in liver surgery. This research aims to advance the capabilities of IOUS-guided interventions by applying an innovative AI-based approach named the "2D-weigthed U-Net model" for the segmentation of multiple blood vessels in real-time IOUS video frames. Our proposed deep learning (DL) model achieved a mean Dice score of 0.92 for IVC, 0.90 for RHV, 0.89 for MHV, 0.86 for LHV, 0.95 for PV, 0.93 for LPV, 0.84 for RPV, 0.85 for RAPV, and 0.96 for RPPV. In the future, this research will be extended for real-time multi-label segmentation of extended vasculature in the liver, followed by the translation of our model into the surgical suite.

The Effect of Physiotherapy on Erectile Dysfunction Secondary to Prostatic Adenectomy: A Randomized Control Trial Study.

The objective of this randomized controlled trial was to investigate the impact of manual therapy (friction massage) and pelvic floor muscle (PFM) training on erectile dysfunction (ED), pelvic floor muscle thickness, and blood flow in the penile arteries and veins in men who have undergone prostatic adenectomy (PA). This study employed a randomized, double-blinded, controlled trial design. Forty patients participated and were divided into two groups: intervention and control (n=20 per group). The intervention group received 10 sessions of pelvic floor muscle training and manual therapy, while the control group solely underwent pelvic floor muscle training. The recovery rate was measured using the International Index of Erectile Function 15 (IIEF-15) questionnaire and Erection Hardness Score (EHS). Sonographic factors were assessed using simple and Doppler ultrasound. The intervention group exhibited significantly higher erectile function scores (F(1,37)=158.04, P < 0.001, η2 P = 0.810) and a higher average total (IIEF-15) score (20.52) (F(1,37)=136.76, P < 0.001, η2 P = 0.787) compared to the control group in the post-test assessment. Comparison between the two groups revealed an increase in ultrasonic parameters such as the thickness of the ischiocavernosus and bulbospongiosus muscles, maximum systolic velocity, and minimum diastolic velocity of the cavernosal artery in the intervention group. However, the maximum blood flow velocity in the posterior vein decreased. PFM training and friction massage play a significant role in managing ED following PA, positioning them as the primary treatment approach for men experiencing ED post-prostatectomy.

Positional Effects of a Fly’s Wing Vein in the Asymmetric Distribution of Hydraulic Resistances

Insect wing vein networks facilitate blood transport with unknown haemodynamic effects on their structures. Fruit flies have the posterior cross vein (PCV) that disrupts the symmetry of the network topology and reduces the total pressure loss during blood transport; however, the impact of its various positions among species has not been examined. This study investigated the haemodynamic effects of this vein with various connecting positions. By analogising venous networks to hydraulic circuits, the flow rates and pressure losses within the veins were derived using Poiseuille’s and Kirchhoff’s laws. The results showed that the total pressure loss decreased for both PCV connections near the wing’s base. In an idealised circuit imitating the network topology, applied high hydraulic resistances as one-sided as those along the edge of the wing, the same pressure loss response as that in the actual network was demonstrated, but not within a symmetric resistance distribution. Therefore, the most proximal PCV minimises the pressure loss within the asymmetric resistance distribution, indicating an evolutionary adaptation to reducing the pressure loss in certain species with this vein near the base. Our findings highlight the possible optimisation of the flies’ wing morphology to maintain the functions of the liquid transport networks and flight devices simultaneously.

Investigating the Effects of Manual Therapy and Pelvic Floor Training on Erectile Dysfunction: A Case Study

Introduction: Erectile dysfunction (ED) is a common issue in men, often associated with various factors, such as obesity, diabetes, and more. This case study examines the impact of friction massage combined with pelvic floor exercises on ED in three patients, linked to prostatic adenectomy, aging, and diabetes. Case Description: Patients followed a one-month regimen of pelvic floor exercises and techniques. The technique’s progress was monitored via video calls twice a week. Exercises lasted for 10 min daily, along with a 10-min massage. We assessed improvement using the international index of erectile function 15 (IIEF15) questionnaire and erection hardness score (EHS), as well as ultrasound scans. Results: Following treatment, all three patients showed increased EHS and IIEF15 15 scores. Muscular thickness increased in the ischiocavernosus and bulbospongiosus muscles, while the cavernosal artery exhibited higher systolic velocity and lower diastolic velocity, although maximum blood flow velocity in the posterior vein decreased. Treatment had the most significant impact on the adenectomy patient, followed by the elderly patient and then the diabetic patient. Conclusion: Combining friction massage and pelvic floor exercises led to improved erection- related indicators and increased patient satisfaction.

Concomitant circumaortic and retro-aortic left renal veins associated with fenestrated renal artery.

Variations of the left renal vein can be in the form of circumaortic vein or renal collar, retro-aortic vein, additional renal vein, or multiple primary tributaries. We report a unique complex venous pattern of concomitant circumaortic and retro-aortic left renal veins associated with a fenestrated left renal artery. Two renal veins, anterior and posterior to the renal artery, originated from the renal hilum. The anterior vein was further divided into two branches. One branch passed through the fenestrated renal artery to continue as the anterior limb of the circumaortic vein. It received the suprarenal and gonadal veins and drained into the inferior vena cava. The other branch coursed posterior to the fenestrated renal artery and joined the posterior renal vein. The posterior renal vein was divided into two branches: one forming the posterior limb of the circumaortic vein, and the other continued obliquely downwards as the retro-aortic vein. Variations in the left renal vein have been implicated in several clinical conditions, such as varicocele and pelvic varices. It also plays a crucial role in renal transplantation, as the left kidney is often used as the donor organ. Even though many reports have been published on circumaortic and retro-aortic veins, the complex venous pattern associated with a fenestrated renal artery has not been reported previously.

An unilateral double fenestration of the right external jugular vein: a rare variant.

This report presents a rare anatomical variation, double fenestration of the External jugular vein on the right side. During the routine dissection of a male cadaver aged 60 years, we observed a unilateral large double fenestration of the External jugular vein on the right side. After its formation from the posterior division of the retromandibular and posterior auricular veins, External jugular vein descended in the posterior triangle of neck. Here, it divided into medial, intermediate, and lateral veins that united again before draining into the subclavian vein. Lateral vein was the largest (7.2cm) and intermediate and medial veins were measuring 6.4cm each. Two large fenestrations, measuring 5.8cm each, arranged like a "double bubble" were seen in the External jugular vein extending from fourth to sixth cervical (C4 to C6) vertebrae. The medial branch of supraclavicular nerve was seen passing superficial to the distal part of External jugular vein. On the left side, the course of External jugular vein showed a standard pattern. Surgeons must be acquainted with the varied anatomy of the superficial neck veins to prevent major bleeding during operative procedures, including carotid endarterectomy, flap operations, & central venous catheterisation.

Extraction of intracardiac electrode located in the posterior interventricular vein, with a mechanical rotational cutting sheath, in a patient with persistent left superior vena cava

Extraction of intracardiac electrode located in the posterior interventricular vein, with a mechanical rotational cutting sheath, in a patient with persistent left superior vena cava

An arteriovenous fistula model: Carotid artery-posterior facial vein fistula in rats.

To describe an alternative arteriovenous fistula (AVF) model involving anastomosis of the common carotid artery (CCA) with the posterior facial vein (PFV). Twenty-two male Sprague-Dawley rats (age 6-8 weeks) were used to establish the AVF model involving end-to-side anastomosis of PFV and CCA. The peak velocity of the CCA and the diameter of the outflow vein were recorded at 7, 14, and 42 days after the operation using Doppler ultrasound. Pathological examination of the intimal lesions was performed at 14 and 42 days after operation. One rat died within 24 h after surgery related to anesthesia. The patency rates at days 7, 14, and 42 were 85.7%, 81%, and 81%, respectively. The diameter of the carotid artery in rats is approximately 0.8 mm. The diameter of the outflow vein was increased by 1.7-fold and 2.2-fold at 7 days (1.1 ± 0.118 mm) and 14 days (1.4 ± 0.073 mm). At 42 days (1.96 ± 0.101 mm) after operation, the diameter was 3-fold greater compared to the unoperated control rat. The peak systolic flow velocity of the carotid artery at 7 days (593 ± 17.36 mm/s) and 14 days (767 ± 13.64 mm/s) after surgery was significantly greater compared to the control rat (314 ± 15.13 mm/s). The rate of increase was fastest at 7 days and leveled off from 14 to 42 days (875 ± 26 mm/s) after surgery. At 14 days, the intima area showed a nearly 50-fold increase (230 ± 9.93 μm2 × 103) compared to control (area 5 ± 0.37 μm2 × 103). Comparing 6 weeks with 2 weeks (280 ± 10.54 μm2 × 103) after surgery, the intima area increased 1.2 times. The CCA-PFV fistula in rats is a viable alternative AVF model.

Use of the Scepter Dual-Lumen Balloon Catheter for Transarterial Onyx Embolization of Cranial Dural Arteriovenous Fistulas

Dual-lumen balloon microcatheters allow for controlled anterograde flow of Onyx while providing proximal flow arrest, thereby obviating the need for a second microcatheter or Onyx plug formation. We sought to assess the safety and efficiency of the Scepter dual-lumen balloon microcatheter in trans arterial Onyx embolization of intracranial dural arteriovenous fistulas (DAVFs). We conducted a retrospective study of 36 patients with cranial DAVFs in which a Scepter balloon microcatheter was used between 2016 and2023. Our study comprised 36 patients, mostly male (n= 23, 63.8%) with a mean age of 60.8 years. Most DAVFs were in the occipital lobe (n= 24, 66.7%), and 50% had external carotid artery supply from the occipital artery. Eighteen (50%) of DAVFs were Cognard type III and IV, respectively. About one third (33.3%, n= 12) of the DAVFs drained into the transverse sigmoid junction, and 27.7% (n= 10) had direct cortical venous drainage into supratentorial or posterior fossa veins. Complete occlusion was obtained in 22 (61.1%) patients while partial occlusion was observed in 14 (38.9%) patients. One patient (2.8%) developed a retroperitoneal hematoma. At final follow-up, complete occlusion was observed in 21 (77.8%) and partial occlusion was observed in 8 (22.2%). Recurrence was observed in 4/30 (13.3%) patients, and retreatment was required in 6 (18.75%) cases. At midterm follow-up, our study showed low morbidity and modest complete occlusion rates using the Scepter for transarterial Onyx embolization of high-grade DAVFs.

Comparative morphological and morphometric analysis of the structure of the wall of the calf venous collectors

Introduction. Development of venous pathology of the lower extremities is based on morphological changes in the vascular wall. Further structural restructuring of the vein wall in chronic venous insufficiency will depend on the initially present differences in the structure of their walls.Aim. To conduct a comparative analysis of morphological and morphometric features of the structure of the walls of the main venous collectors of the lower leg: the great saphenous vein, intramuscular veins, posterior tibia veins and poplitea vein.Materials and methods. Histological studies were carried out on autopsy material of the veins of 32 people who died from various causes aged 35 to 50 years and 10 amputated limbs. Morphological studies of the venous wall were carried out by light microscopy with digital photo processing.Results. A quantitative comparative analysis of morphological changes with the determination of the volume fraction of smooth muscle and connective tissue elements of various membranes of the venous wall, as well as measurement of the total thickness of the vascular wall and its ratio to the lumen of the veins showed statistically significant differences at a significance level of p &lt; 0.05.Discussion. Despite the similarity of the general morphological picture of the structure of various venous collectors of the lower leg, structural differences were established, which concerned the volume fraction of the presence of both smooth muscle and connective tissue elements.Conclusion. The comparative qualitative and quantitative statistical analysis of morphological and morphometric features of the structure of the walls of the main venous collectors of the lower leg allows us to make an assumption about the unequal role of individual main venous collectors in the work of the muscular-venous pump of the lower leg as a whole.

Mastoid Emissary Foramina in Dry Skulls: Its Morphometry, Topography, and Associated Clinical Implications.

Mastoid emissary foramen transmitting mastoid emissary vein connects the posterior auricular vein with the sigmoid sinus. This foramen and so the mastoid emissary vein varies in prevalence, number, size and location, knowledge of which is essential for carrying out uneventful surgeries, especially retrosigmoid, mastoidectomy, and skull base surgeries. There is a paucity of literature on this foramen in the Indian context, so the study was done. The purpose of the study is to elaborate on the prevalence, number, size, and location of mastoid foramen in dry adult skulls. The study was conducted in the Department of Anatomy using 90 dry skulls of unknown age and sex, and prevalence, number, size, and location in these skulls were noted. The mastoid foramen was detected in 27.8% of skulls, with an incidence of 31.1% and 12.2% on right and left sides of skulls, respectively. The number of foramina ranged between 1 and 4. The mean diameter of this foramen was 0.9mm, and the most frequent location was mastoid process. The detailed morphology and morphometry of mastoid foramen are of utmost use to neurosurgeons, ENT surgeons, radiologists, and vascular surgeons as it transmits mastoid emissary vein and meningeal branch of the occipital artery, which may be injured during various surgical procedures involving mastoid region and skull base causing catastrophic hemorrhage. In addition to this, mastoid emissary vein may be the source of thrombus, causing thrombus of sigmoid sinus creating helm of neurological complications.

Association between the arm-to-choroidal circulation time and clinical profile in patients with polypoidal choroidal vasculopathy.

To investigate the association between the arm-to-choroidal circulation time (ACT) on indocyanine green angiography (IA) and clinical profile in patients with polypoidal choroidal vasculopathy (PCV). Single-center retrospective study. We included 38 eyes of 38 patients with PCV diagnosed using multimodal imaging and did not undergo previous treatment. All patients were treated with monthly aflibercept injections for 3 months and treat-and-extend regimens for the subsequent 12 months. Posterior vortex vein ACT was assessed on the first visit using Heidelberg IA. The patients were divided into two groups: ACT ≥20 s (L group; eight eyes) and ACT <20 s (S group; 30 eyes). The clinical profiles before and after treatment were analyzed to assess associations with ACT. The mean ACT was 16.39±3.3 s (L group: 21.25±1.49 s, women:men=2:6, mean age: 77.3±6.5 years; S group: 15.10±2.17 s, women:men=7:23, mean age: 75.5±6.9 years). No significant difference was observed in the mean subfoveal choroidal thickness between the L and the S groups (176±75 μm vs. 230±79 μm, P=0.10). However, there were significant differences between the L and S groups in retinal fluid accumulation and hemorrhage recurrence (eight/eight eyes, 100% vs. 13/30 eyes, 43%, P<0.001), mean aflibercept injections (8.8±1.6 vs. 7.0±1.6, P<0.01) during the 12-month period, and the number of polypoidal lesions (1.8±0.7 vs. 1.3±0.5, P<0.05). Patients with PCV and ACT >20 s are more likely to experience exudative change recurrence in the retina during treatment because they have more polypoidal lesions.

Circuit analogy unveiled the haemodynamic effects of the posterior cross vein in the wing vein networks.

We investigated the wing vein network topology in fruit flies and observed that the posterior cross vein (PCV) disrupts the symmetry of the entire network. The fluidic engineering function of this vein's disposition remains unexplored although the wing vein network is known to transport blood. We examined the fluid mechanical effects of the PCV's disposition on this blood-transporting network through numerical simulations involving the removal and rearrangement of the vein, avoiding impractical physical manipulation. We characterised the geometry of each wing membrane cell, a portion of the wing membrane surrounded by a group of veins, by determining the ratio of its surface area to the contact area with the veins. We considered this ratio in association with the flow velocities of seeping water from the blood within the veins to the membrane and evaporating water from the membrane, based on the mass conservation law. We observed that the division of a membrane cell by the PCV maximises the ratio of the areas in the divided cell on the wing-tip side by virtually shifting this vein's connections in our geometric membrane model. We derived blood flow rate and pressure loss within the venous network from their geometry, using an analogy of the venous network with a circuit consisting of hydraulic resistors based on Kirchhoff and Ohm's laws. The overall pressure loss in the network decreased by 20% with the presence of the PCV functioning as a paralleled hydraulic resistor. By contrast, any other cross-vein computationally arranged on another membrane cell as the PCV's substitution did not exhibit a larger reduction in the pressure loss. Overall, our numerical analyses, leveraging geometry and a circuit analogy, highlighted the effects of the PCV's presence and position on the blood-transporting vein network.

A Rare Combined Variation of the Fenestrated External Jugular Vein, Absent Retromandibular Vein, and Hypoplastic Internal Jugular Vein

A unique venous pattern was observed on the left side of the neck in a 70-year-old male cadaver. Variations were observed in the formation of the external jugular vein (EJV) associated with a hypoplastic internal jugular vein (IJV). The retromandibular vein did not form, and the superficial temporal vein continued as the EJV. The linguofacial and maxillary veins united and drained into the EJV, whereas the posterior auricular vein was absent. In addition, a slit-like fenestration in the EJV was present in the middle of the vein, which was 41.54 mm long. IJV of the same side was hypoplastic throughout its course in the neck, and the external diameter was 6 mm. IJV and EJV are frequently accessed for central venous pressure monitoring or intravenous infusion and are encountered during cervical lymphadenectomy. Awareness of the anatomical irregularities is critical to avert unanticipated complications.

Basketball Anterior and Posterior Portal Veins Doppler Imaging of Sports Medicine Technique Exploration

INTRODUCTION: Basketball, as a high-intensity sport, has attracted much attention for its effects on the cardiovascular system of athletes. The anterior and posterior portal veins are some of the vital blood vessels in the human circulatory system, and their blood flow is closely related to the athletes' physical status. Doppler ultrasound technology is widely used in sports medicine and provides a powerful tool for an in-depth understanding of the effects of basketball on portal vein blood flow. This study aimed to explore the potential of sports medicine technology in assessing cardiovascular adaptations in athletes through portal Doppler imaging before and after basketball exercise.OBJECTIVES: The primary objective of this study was to analyze the effects of basketball exercise on portal vein blood flow in athletes before and after basketball exercise through the use of Doppler ultrasound technology. Specifically, this study aimed to explore the dynamics of pre- and post-exercise Doppler imaging of the posterior and posterior veins in order to assess the cardiovascular adaptations of athletes during exercise more comprehensively and objectively.METHODS: A group of healthy professional basketball players were selected as the study subjects, and Doppler ultrasound instruments were utilized to obtain portal Doppler images before, during, and after exercise. The functional status of the vasculature was assessed by analyzing parameters such as portal blood flow velocity and resistance index. At the same time, the physiological parameters of the athletes, such as heart rate and blood pressure, were combined to gain a comprehensive understanding of the effects of basketball on portal blood flow.RESULTS: The results of the study showed that the anterior and posterior portal blood flow velocities of the athletes changed significantly during basketball exercise. Before the exercise, the blood flow velocity was relatively low, while it rapidly increased and reached the peak state during the exercise. After exercise, blood flow velocity gradually dropped back to the baseline level. In addition, the change in resistance index also indicated that portal blood vessels experienced a particular stress and adaptation process during exercise.CONCLUSION: This study revealed the effects of exercise on the cardiovascular system of athletes by analyzing the Doppler images of the portal vein before and after basketball exercise. Basketball exercise leads to significant changes in portal hemodynamics, which provides a new perspective for sports medicine. These findings are of guiding significance for the development of training programs for athletes and the prevention of exercise-related cardiovascular problems and provide a valuable reference for further research in the field of sports medicine.

Remodeling of extracranial veins and venous-arterial imbalance in extrinsic stenosis and hypoplasia of the internal jugular veins

The aim of the study was to compare hemodynamic parameters, the sequence of remodeling of the jugular and extrajugular outflow tracts of cerebral venous circulation in extrinsic stenosis and hypoplasia of the internal jugular vein (IJV). Material and methods. Groups with external compression and IJV stenosis (n = 50), with IJV hypoplasia (n = 27), and after IJV ligation/resection (n = 6) as a model of IJV occlusion with a minimal cerebral venous insufficiency and venous encephalopathy and control group (n = 31) were compared. All patients underwent a neurological examination, ultrasound duplex scanning of the IJV (J2 and at the level of stenosis), common carotid and vertebral artery (V2), 2DToF or 3DToF magnetic resonance venography of the neck veins. The degree of stenosis of the IJV, the crosssectional area and the time average blood flow velocity, the calculated indicator of the venous-arterial balance (VAB) were determined according to the modified formula. Results and discussion. In the group of external compression of the IJV, stenosis averaged 64.52 %. The area of the IJV at the site of stenosis was 6 times, and at the standard place (J2) – 3 times less than the area of the opposite IJV. The hypoplastic IJV throughout its entire length (from J1 to J3) had the same area (0.21 ± 0.12 cm2 ), smooth contours, without local expansions or narrowings. A very low blood flow velocity (10.2 ± 11.67 cm/s) is characteristic for stenosis, in contrast to the normal velocity in the hypoplastic vein and in the control group. The blood flow velocity in the contralateral IJV with external stenosis does not differ from normal, but it is increased with hypoplasia (34.62 ± 12.23 cm/s). With MR venography, it is possible to detect a stenosing factor, symptoms of a filling defect, a decrease or loss of a blood flow signal, and an assessment of the overall picture of remodeling of the venous network of the neck. A decrease in the IJV area on the side of the lesion/anomaly corresponds to negative remodeling, while an expansion of the opposite IJV corresponds to positive remodeling. If the obstruction persists, the homolateral, then the contralateral external jugular vein expands, then the vertebral veins and plexuses, spinal epidural veins, anterior jugular and posterior cervical veins expand too. The magnitude of the IJV on the side of the anomaly/pathology with hypoplasia did not differ from the value with stenosis (9 %), but was slightly less than on the opposite IJV (53.39 ± 13.40 and 67.24 ± 18.02 %, respectively, p &lt; 0.06) and significantly less compared to the control (24.16 ± 8.06 % on the left and 33.15 ± 8.27 % on the right, p &lt; 0.0001), which makes this indicator a good additional criterion for outflow abnormality according to the IJV of one side.

LONGITUDINAL CHANGES OF POSTERIOR VORTEX VEINS IN HIGHLY MYOPIC EYES DETERMINED BY RETROSPECTIVE ANALYSES OF INDOCYANINE GREEN ANGIOGRAMS.

To assess the longitudinal changes of the posterior vortex veins (VVs) in highly myopic (HM) eyes. The medical records of 1,730 consecutive HM eyes that had undergone indocyanine green angiography were studied. Eyes that had posterior VVs and had undergone at least two indocyanine green angiography examinations with a minimum interval of 3 years were selected from this group. Ninety-one eyes of 78 patients met the inclusion criteria. A total of 124 posterior VVs were identified. Over an average interval of 7.8 ± 5.0 years, 41 (33.1%) of the 124 posterior VVs had marked changes consisting mainly of an attenuation of vessels in 36 posterior VVs (87.8%) and alterations in the drainage course in 16 posterior VVs (39.0%). Fifteen posterior VVs had both types of changes. Most of the attenuations of the vessels occurred for smaller branches, but a complete loss of the entire trunk was seen in three eyes. Additionally, four eyes had posterior VV changes in association with changes of peripheral VVs. Posterior VV in highly myopic eyes can undergo changes with increasing time. The associated factors included the development and progression of myopic maculopathy lesions. In some cases, the blood drainage shifted from posterior VV to peripheral VV by forming anastomotic channels.

A Novel Exploration of the Choroidal Vortex Vein System: Incidence and Characteristics of Posterior Vortex Veins in Healthy Eyes.

The purpose of this study was to investigate the incidence and characteristics of posterior vortex veins (PVVs) in healthy eyes and explore their relationship with age and refractive status. This retrospective cross-sectional analysis encompassed 510 eyes from 255 consecutive healthy participants. Wide-field optical coherence tomography angiography (WF-OCTA) imaging was used to assess the presence of PVVs. Eyes were classified according to refractive status (emmetropia, low and moderate myopia, and high myopia) and age (minors and adults). The incidence and characteristics of eyes with PVVs were analyzed. Participants (mean age = 30.60 ± 21.12 years, 47.4% men) showed a mean refractive error of -2.83 ± 3.10 diopters (D; range = -12.00 to +0.75). PVVs were observed in 16.1% (82/510) of eyes. Of these, 39% (32/82) had PVVs in one eye and 61% (50/82) in both eyes. The mean number of PVVs per eye was 1.65 ± 1.05 (range = 1-6). PVVs are mainly around the optic disc (78%, 64/82) of eyes with PVVs and less in the macular area (6.1%, 5/82) or elsewhere (15.9%, 13/82). PVV incidence correlated with refractive status: 10.3% (22/213) in emmetropia, 16.6% (31/187) in low and moderate myopia, and 26.4% (29/110) in high myopia (P = 0.001), but not with age. Refractive status was the key predictor of PVV occurrence (odds ratio [OR] = 1.45, 95% confidence interval [CI] = 1.02-2.06, P = 0.038). This study confirms PVVs' presence in healthy eyes, highlighting their inherent existence and susceptibility to alterations due to refractive conditions. These findings enhance our understanding of the vortex vein system and its distribution within the eyes.

Posterior Fossa Anatomy for Microvascular Decompression Surgery

In most microvascular decompression surgeries, surgical maneuvers are performed within normal anatomical structures without any neoplasms. Thus, detailed anatomical knowledge is essential to perform safe and efficient procedures. "Rule of 3" by Rhoton AL Jr. is helpful for understanding not only the anatomy of the posterior fossa but also the three neurovascular compression syndromes. The cerebellar arteries and posterior fossa veins have substantial variability, but a basic understanding of their typical patterns is useful to explore individual cases. To use adequate surgical approaches through the cerebellar tentorial or petrosal surface in individual trigeminal neuralgia surgeries, anatomical knowledge of the bridging veins on the tentorial(the bridging veins into the tentorial sinus)and petrosal surfaces(the superior petrosal vein)is crucial. Fissure openings help to minimize cerebellar retraction, similarly to the sylvian fissure dissection in supratentorial surgeries.