Posterior Vein Research Articles

Introducing the Posterior Condylar Emissary Vein as an Effective Surgical Landmark for Optimizing the Standard Retrosigmoid Approach: An Anatomo-Imaging Study

There is a lack of definite anatomical landmarks for the inferior extension of the standard retrosigmoid approach. In this study, we evaluated whether the posterior condylar emissary vein (PCEV) can be used as an intraoperative landmark for optimizing the surgical corridor. We performed the standard retrosigmoid approach on 5 formalin-fixed and latex-injected cadaveric specimens and measured the distance between the PCEV near its bony canal and the vertebral artery (VA). In addition, vascular reconstructions of thin-sliced preoperative computed tomography (CT) scans were studied in 40 patients and the relationship between these 2 vessels was evaluated. An illustrative case is also included. The PCEV was consistently identified on both sides of cadaveric specimens and in 87.5% and 82.5% of the left and right sides of the included CT scans, respectively. The average distance between the part of the PCEV near its osseous canal and the VA was measured to be between 8.4 mm and 8.6 mm in the specimens and between 9.2 mm and 9.3 mm in the CT scans. This distance offers a safe and effective plane of dissection during the standard retrosigmoid approach and allows easy access to the foramen magnum. The PCEV near its bony canal proved to be an easy, straightforward, safe, and effective operative landmark with which the surgeon can extend the soft tissue dissection and bony exposure towards the foramen magnum. This maneuver provides ample access to the cisterna magna for cerebrospinal fluid drainage and increases visibility and surgical maneuverability to the entire cerebellopontine angle.

First Eugereonidae (Insecta: Palaeodictyoptera) from the Pennsylvanian (Late Carboniferous) of the Piesberg site near Osnabrück, Germany

Sandiella herbigi sp. nov. is the first record of the family Eugereonidae Handlirsch, 1906 (Insecta: Palaeodictyoptera) in the Pennsylvanian (Late Carboniferous: Westphalian D) sequence of the Piesberg quarry near Osnabrück, Lower Saxony, Germany. It is represented by a single fragment of a mesothoracic wing with the typical coarse reticulation in this family. The species is mainly characterized by the following features: (i) the shape of the mesothoracic wing is extremely narrow, (ii) the posterior subcostal vein is ending before the wing apex, (iii) all the main veins show a typical bend close to the posterior margin. The new wing is the second most ancient record of the Eugereonidae.

Effects of the visualized steerable sheath applied to catheter ablation of paroxysmal atrial fibrillation.

A new type of visualized steerable sheath (Vizigo sheath; Biosense Webster Inc., Irvine, CA, USA) has been employed in clinical treatment. This study aimed to compare the effectiveness and safety of the Vizigo sheath to a fixed sheath (Swartz sheath; St. Jude Inc., St. Paul, MN, USA) for catheter ablation of paroxysmal atrial fibrillation (PAF). We analyzed the procedural time, fluoroscopy time, contact force (CF), and initial pulmonary vein isolation (PVI) rate. After 6months of follow-up, the success rate of ablation between the two groups was compared. Compared to the Swartz sheath, using the Vizigo sheath can significantly reduce the total procedural time and fluoroscopy time and increase the overall average CF, especially in the anterior left pulmonary vein (LPV), superior LPV, posterior right pulmonary vein (RPV), and superior RPV. The proportion of CF within a reasonable range in the Vizigo group was significantly higher than that in the Swartz group, especially in the anterior LPV, posterior RPV, and superior RPV. Besides, the left, right, and bilateral initial PVI rates in the Vizigo group were significantly higher. The visualized steerable sheath for PAF catheter ablation not only reduced radiation exposure but also significantly improved CF and initial PVI rate, all of which indicated an increased rate of successful ablation.

Abstract 11684: Meta-Analysis of Contemporary Hybrid Convergent Ablation Outcomes

Introduction: Recent randomized clinical trial data demonstrated safety and effectiveness of hybrid epicardial-endocardial (convergent) ablation for persistent and longstanding persistent atrial fibrillation (PersAF/LSPAF). The objective of this study was to perform a systematic review and meta-analysis focused on contemporary hybrid convergent procedure outcomes. Methods: Predefined search terms were used in PubMed/EMBASE in May 2021. Abstracts and full text in English were reviewed for peer-reviewed, primary clinical studies of hybrid convergent procedures in PersAF/LSPAF using the current unipolar device for epicardial ablation and lesion set focused on left atrial posterior wall and pulmonary vein isolation. Meta-analysis was performed with using a random effects model with a restricted maximum likelihood estimator and forest plots. Heterogeneity was tested using Cochran’s Q-test. Results: The updated search yielded 155 unique results. Two articles from manual searching were added. Twenty-seven full text articles were assessed for inclusion. Six articles that included 551 patients were identified for qualitative and quantitative analysis. Ninety-six percent of patients had persistent or long-standing persistent AF. Mean/median pre-operative AF duration ranged from 2 to 5 years. The 30-day major adverse event rate was 6% (95% CI 3-8%, n=551, 6 studies). No atrioesophageal fistulas or periprocedural mortality events were reported. Freedom from atrial arrhythmia at one year or later was 69% (95% CI 61-78%; n=523, 6 studies) regardless of anti-arrhythmic drugs (AADs) and 50% (95% CI 42-58%; n=343; 3 studies) off AADs. Heterogeneity was insignificant for effectiveness off AADs (p=0.14) and safety (p=0.23) Conclusions: This meta-analysis found favorable effectiveness of contemporary hybrid convergent procedures at one year, even off AADs, and a reasonable safety profile in mostly persistent or long-standing persistent AF.

Abstract 13439: Long-Term Outcomes From Continuous Rhythm Monitoring After Hybrid Convergent Procedure in Longstanding Persistent Atrial Fibrillation Patients

Introduction: Endocardial catheter ablation has suboptimal effectiveness and durability in patients with longstanding persistent atrial fibrillation (LSPAF). Hybrid convergent ablation combines epicardial and endocardial ablation to create a transmural lesion set that isolates the left atrial posterior wall and pulmonary veins. The study objective was to evaluate long-term outcomes assessed by continuous rhythm monitoring in LSPAF patients who received hybrid convergent ablation. Methods: This was a single-center IRB-approved, observational study. Eligible patients were identified by retrospective chart review and included patients who received hybrid convergent procedures between September 2011 and November 2017. Patients were consented for prospective long-term follow-up visits and continuous cardiac monitoring (7-day ePatch). Baseline characteristics, procedural outcomes, and follow-up data were entered into the TRAC-AF registry. This analysis focused on the patient subgroup with pre-operative LSPAF (AF duration >1 year). Results: Of 77 consented patients, 60 had pre-operative LSPAF. Mean age was 66.1 ± 7.9 years, 70% were male, and duration of AF was 6.8 ± 4.8 years. Mean CHA2DS2-VASc score was 2.6 ± 1.4; mean BMI was 32.1 ± 5.9, and 55% (33/60) of patients had previous catheter ablation. Thirty-day major adverse event rate was 5% (3/60) and included 2 inflammatory pericardial effusions and one major bleeding. On continuous monitoring, 71% (41/58) of patients had 0% AF burden at mean follow-up of 61.7 ± 18.9 months. Eight patients (13%) had repeat catheter ablation at mean 21.6 ± 16.3 months since index procedure. Comparison of baseline and follow-up left ventricular ejection fraction (LVEF) from echocardiography revealed a trend of 12.4 ± 13.0 units improvement at mean follow-up of 18.2 ± 23.7 months since baseline in 5 patients with severely reduced (<40%) baseline ejection fraction (p=0.063). Conclusions: Long-term follow-up with continuous monitoring revealed a majority of patients with pre-operative LSPAF had 0% AF burden after a mean 61.7 months since the hybrid convergent procedure. These results are aligned with published studies and the CONVERGE trial on the effectiveness of hybrid convergent ablation in LSPAF.

Nontraumatic Atlantoaxial Rotatory Subluxation: A Rare Complication of COVID-19 in Elderly Patient

Introduction: Nontraumatic Atlantoaxial Rotatory Subluxation (NAAS) or Atlantoaxial Rotatory Subluxation (AARS) without trauma or concomitant bone pathology was first described by Sir Charles Bell in 1830 in a patient with syphilis and pharyngitis, who developed lethal outcome due to spinal compression. The syndrome was named after Grisel who described two cases of pharyngitis and atlantoaxial subluxation in 1951. However, this is an uncommon condition of uncertain etiology characterized by NAAS, usually seen in children secondary to an infection and inflammation in the head and neck region or otolaryngeal procedures. Patients generally complain about neck stiffness and pain, and sometimes dysphagia may occur. Diagnosis is established based on the clinical and radiological findings. The etiopathogenesis and the underlying pathomechanics have not been clearly explained. A hematogenous spread of infection from the posterior pharynx to the cervical spine, according to the recent literature, with hyperemia and abnormal relaxation of the atlantoaxial ligaments is a widely accepted theory. The vascular plexus providing the drainage of poster superior pharyngeal area is responsible. The periodontoid plexus is connected with posterior nasopharyngeal veins via the pharyngovertebral vein. Any infective embolism may spread from superior pharyngeal area to upper cervical joints due to this plexus which does not have any lymph node, thus providing an anatomical explanation for the atlantoaxial hyperemia reported in Grisel's syndrome; however, the clinical picture and complications of COVID-19 are unclear until now and every day new symptoms and findings are reported as early and late complications.
 Methodology: An 86-year-old male presented to our clinic in KKT, Jeddah from Yanbu (which is 330 km away) with a complaint of neck stiffness in anterior-lateral position after recovery from COVID-19 six months back. The patient was treated at home without admission in hospital. He had no history of trauma. During the physical examination, the patient's neck was stiff, and there was neck pain with palpation and left-sided torticollis. The patient’s weight was 58 kg, height 160 cm, blood pressure 140/75 mmHg with a pulse rate of 72, SPO2 95, and BMI 22.7. There was no sign of fever or any type of inflammation in his body. The patient had previously consulted neurosurgeons at three different hospitals in Jeddah and was advised a medication with a cervical collar for a clinical follow-up. After three weeks of follow-up, they advised him to start physiotherapy for one month with no benefits seen in clinical finding, the patient then came to us. Direct radiogram of the cervical region showed suspicious findings at the atlantoaxial joint. Anterior view of the cervical radiography revealed tilted position of the head over neck, while the lateral view showed no thickening of the parapharyngeal soft tissue. The distance between the axis and dens was within normal values for his age (ADI = 3–4 mm). This confirms our diagnosis of type 1 atlantoaxial subluxation according to Fielding and Hawkins classification.
 Result: Based on the patient’s history and physical examination, there was no infection or neck operation causing an inflammation in the neck except the COVID-19 six months prior to the neck stiffness. With this case, we would like to highlight that atlantoaxial subluxation should be kept in mind when neck stiffness is seen in elderly patient without history of trauma but with a history of COVID-19 as a rare complication.
 Conclusion: NAAS is a rare but major complication that can often go unnoticed in its early and late phase, which can be a major cause of morbidity following COVID-19 infections, thus early recognition and diagnosis is mandatory especially in adult and elderly patients recovering form COVID-19.

Clinical comparative study of free posterior tibial artery perforator flap and radial forearm free flap for head and neck reconstruction

Objective: To compare the clinical application results of the FPTF (free posterior tibial artery perforator flap) and RFFF (radial forearm free flap) for reconstruction of head and neck defects. Methods: A retrospective analysis of 27 cases treated with FPTF (19 males and 8 females, aged 14-69 years) and 24 cases with RFFF (11 males and 13 females, aged 22-69 years) for head and neck defect reconstruction at Beijing Tongren Hospital of Capital Medical University from January 2015 to December 2020 was conducted. Flap size, vascular pedicle length, matching degree of recipient area blood vessels, preparation time, total operation time, hospital stay, recipient area complications, donor area complications and scale-based patient satisfaction were compared between two groups of patients with FTPF and RFFF. SPSS 26.0 statistical software was used for statistical analysis. Results: There was no statistically significant difference between the two groups of patients in tumor T staging (P=0.38), primary sites (P=0.05) and mean flap areas ((53.67±29.84) cm2 vs. (41.13±11.08) cm2, t=-1.472, P=0.14). However the mean vascular pedicle length of FPTF was more than that of RFFF ((11.15±2.48)cm vs. (8.50±1.69)cm, t=-4.071, P<0.01). The donor sites of 4 patients in FPTF group could be sutured directly, while all the 24 patients in RFFF group received skin grafts from the donor sites. There was no statistically significant difference in the recipient area arteries between two groups of flaps (P=0.10), with more commonly using of the facial artery (RFFF: FPTF=21∶27), but there was significant difference in the recipient area veins (P<0.01), with more commonly using of the external jugular vein in RFFF (14/24) than FPTF (4/32) and the posterior facial vein in FPTF (27/32) than RFFF (9/24). There were 10 recipient complications and 3 donor complications in RFFF group; no recipient complication and 3 donor complications occurred in FPTF group. With patient's subjective evaluation of the donor site at 12 months after surgery, FPTF was better than RFFF (χ²=22.241, P<0.01). Conclusions: FPTF is an alternative to RFFF in head and neck reconstruction and has unique advantages in aesthetics and clinical application.

Evaluation of the effectiveness of the use of low-traumatic surgical access in the reverse shoulder arthroplasty

BACKGROUND: The number of reversible shoulder joint endoprostheses installed in the world at the present stage is several times greater than the number of hemiarthroplasty performed. Nevertheless shoulder arthroplasty is considered a traumatic operation and can be accompanied by a number of complications, both from the side of implants and due to the traumatic nature of the surgical technique. During surgical interventions on the shoulder joint with a wide dissection of the skin and subcutaneous tissue, iatrogenic damage to structures such as the axillary nerve, posterior and anterior arteries and veins surrounding the humerus can often be detected, which triggers a whole cascade of pathophysiological and regulatory processes in which Interventions immediately release inflammatory mediators. Therefore, orthopedic traumatologists strive to reduce the risk of intra- and postoperative complications, and it is necessary to improve the surgical technique of surgical interventions towards their less traumatic performance.&#x0D; AIM: Development and evaluation of the effectiveness of the use of low-traumatic surgical access when performing reverse shoulder arthroplasty.&#x0D; MATERIALS AND METHODS: In the period 20172020, 169 patients with various diseases, injuries of the shoulder joint and their consequences were operated on in the Department of Adult Orthopedics of the N.N. Priorov National Research Medical Center of the Russian Federation, who underwent reverse shoulder arthroplasty according to generally accepted indications. In the main group (84 patients), surgical treatment was performed using a low-traumatic surgical approach, while the control group (85 patients) underwent standard procedures. Functional, clinical and radiological results of surgical treatment of patients of the main and control groups were evaluated and compared after 3, 6 and 12 months.&#x0D; RESULTS: In the main group, excellent results (25 points on DASH) were observed in 73 patients, good results (2650 points) in 10 patients. In 1 patient, the results were assessed as satisfactory (5175 points). In the control group of observation, the clinical result was worse (68 excellent, 16 good and 1 satisfactory result).&#x0D; CONCLUSION: On the basis of the performed study, taking into account the better results in the main group of patients, the technique of low-traumatic surgical access for reverse shoulder arthroplasty can be recommended for wide use in clinical practice.

Incidence of Extrahepatic Portal Vein Anatomic Variations and Their Clinical Implications in Daily Practice.

Anatomical variations of the portal vein are relatively common and can affect the outcomes of hepatic resections, transplantations and interventional radiological procedures. The aim of this study was to review the literature regarding extrahepatic portal vein anomalies. Two main databases were searched for suitable articles, and results concerning more than 3,700 patients were included in the analysis. The most common anatomical variations of the portal vein were trifurcation and having a right posterior portal vein as the first branch of the main portal vein; these anomalies were found in 11.7% and 10.8% of cases, respectively. J Clin Med Res. 2021;13(9):460-465 doi: https://doi.org/10.14740/jocmr4581

Incidence of Extrahepatic Portal Vein Anatomic Variations and Their Clinical Implications in Daily Practice.

Anatomical variations of the portal vein are relatively common and can affect the outcomes of hepatic resections, transplantations and interventional radiological procedures. The aim of this study was to review the literature regarding extrahepatic portal vein anomalies. Two main databases were searched for suitable articles, and results concerning more than 3,700 patients were included in the analysis. The most common anatomical variations of the portal vein were trifurcation and having a right posterior portal vein as the first branch of the main portal vein; these anomalies were found in 11.7% and 10.8% of cases, respectively.

Study of Various Patterns of Azygos Venous System and its Clinical Significance

Background: The azygos system includes those veins which are straight in course, paravertebral in positionand not accompanied with the corresponding arteries. The azygos vein may arise as lumbar azygos veinfrom the back of inferior vena cava or by the union of right subcostal and right ascending lumbar veins. Itenters the thorax, receives lower 8 right posterior intercostal veins, superior intercostal vein, hemiazygosand accessory hemiazygos veins and ends by joining the superior vena cava. The hemiazygos vein is formedon the left in a manner similar to that of azygos vein. The aim of the present study was to investigate thevarious patterns of the azygos venous system.Methods: A total number of 30 cadavers were studied and were evaluated based on the study of Anson BJand Mcvay CB.Conclusion: Out of 30 specimens studied, 17 (56%) specimens showed normal pattern, 5 (16%) specimensshowed caterpillar pattern and rest 8 (26%) specimens showed ladder pattern.Azygos system of veins serve as an alternative drainage channel between superior vena cava and inferiorvena cava in case of obstruction. The knowledge of various patterns could be useful for radiologists andsurgeons to prevent intra-operative hazards.

Collaterals in portal hypertension: anatomy and clinical relevance.

Portal hypertension is a key pathophysiology of chronic liver diseases typified with cirrhosis or noncirrhotic portal hypertension. The development of collateral vessels is a characteristic feature of impaired portal hemodynamics. The paraumbilical vein (PUV), left gastric vein (LGV), posterior gastric vein (PGV), short gastric vein (SGV), splenorenal shunt (SRS), and inferior mesenteric vein (IMV) are major collaterals, and there are some rare collaterals. The degree and hemodynamics of collateral may affect the portal venous circulation and may compensate for the balance between inflow and outflow volume of the liver. Additionally, the development of collateral shows a relation with the liver function reserve and clinical manifestations such as esophageal varices (EV), gastric varices, rectal varices and the other ectopic varices, hepatic encephalopathy, and prognosis. Furthermore, there may be an interrelationship in the development between different collaterals, showing additional influences on the clinical presentations. Thus, the assessment of collaterals may enhance the understanding of the underlying pathophysiology of the condition of patients with portal hypertension. This review article concluded that each collateral has a specific function depending on the anatomy and hemodynamics and is linked with the relative clinical presentation in patients with portal hypertension. Imaging modalities may be essential for the detection, grading and evaluation of the role of collaterals and may help to understand the pathophysiology of the patient condition. Further investigation in a large-scale study would elucidate the basic and clinical significance of collaterals in patients with portal hypertension and may provide information on how to manage them to improve the prognosis as well as quality of life.

Interhemispheric Precuneus Retrosplenial Transfalcine Approach for Falcotentorial Meningiomas: Anatomic Study and Clinical Series

Falcotentorial meningiomas are surgically challenging. Currently accepted approaches include occipital interhemispheric and supracerebellar infratentorial approaches, which have documented drawbacks. To propose an alternative approach to the posterior tentorial incisural space, the interhemispheric precuneus retrosplenial transfalcine approach (IPRTA). A total of 6 colored-silicone-injected adult cadaveric heads were dissected. We measured the interval between bridging veins and studied computed tomography venography scans of 20 subjects to confirm the feasibility of the IPRTA. Bony landmarks, the region's bridging veins, and the anterior and posterior borders of the approach were identified. The surgical corridor widths (veins' interval) and lengths were compared between alternative midline approaches. We also reviewed 4 consecutive clinical cases using this approach. The IPRTA provides the shortest distance to the anterior and posterior limits of the posterior tentorial incisura. Moreover, it is the only approach that provides direct visualization of the anterior and posterior limits of falcotentorial junction meningiomas. In all specimens and patients, a minimum 30-mm interval between the anterior and posterior parietal veins was found in at least one of the hemispheres. Tumor removal was successful in all 4 patients but resulted in mild paresthesia in the lower extremities of 2 patients and temporary foot drop in 1 patient. The IPRTA offers the shortest and most direct corridor for falcotentorial meningiomas and provides excellent visualization of most of the critical structures in the region. Detailed preoperative evaluation of the deep and superficial venous structures is recommended.

Microsurgical Anatomy of the Inferior Petroclival Vein and its Relation to Surrounding Structures: A Cadaveric and Radiological Study.

The inferior petroclival vein (IPV) courses along the extracranial surface of the petroclival fissure. It is occasionally involved in vascular diseases and has recently been used for vascular access to the cavernous sinus. However, detailed descriptions of its anatomy are currently lacking. To define the anatomic relationship between the IPV and its surrounding structures based on cadaveric dissection and radiological analysis. A dry skull and an injected cadaver head were examined to reveal the relationships between the IPV and its surrounding structures. The existence of the IPV and its relationships with other venous structures were also examined by contrast-enhanced, fat-suppressed T1-weighted magnetic resonance imaging in 26 patients (51 sides). The entire course of the IPV was shown via stepwise cadaver dissection from below. Its relationships with surrounding structures, such as the jugular bulb, sigmoid sinus, inferior petrosal sinus, petrosal venous confluence, and the posterior, lateral, and anterior condylar veins, were also shown. In the radiological analysis, the IPV was identified on all sides. The rostral end of the vein was connected to the venous plexus around the carotid artery on all sides. The vein drained into the caudal end of the inferior petrosal sinus (49/51 sides, 96.1%) or into the anterior condylar vein (2/51 sides, 3.9%). A precise understanding of the anatomy of the IPV will enable endovascular and skull base surgeons to achieve diagnoses and gain safe access to lesions involving the IPV.

Evaluation of variation of portal vein branching pattern on Multidetector Computed Tomography in adult population

Introduction: The main aim of this study was to determine the prevalence of main and right portal vein variation in study population and evaluate their branching patterns on abdominal CT. Methods: A hospital based cross sectional study was carried out in Department of Radiology, BPKIHS over a period of 6 months after taking ethical approval from institutional review committee. 375 cases referred for abdominal CT for various indications were included in the study. Results: Classic main portal vein branching pattern (Type 1) was identified in 305 (81.3%) cases. Main portal vein branching variations were identified in 70 (18.7 %) cases of which most common variation was trifurcation pattern (Type 2) seen in 48 (12.8%) cases followed by right posterior portal vein as first branch of main portal vein (Type 3) seen in 21 (5.6%) cases. Out of 305 cases with Type 1 branching pattern, classic branching pattern of right portal vein was noted in 285 (93.4%) cases. Right portal vein variations were identified in 20 (6.5%) cases. Common variations of right portal vein noted in our study were early origin of segment VlI branch from right portal vein seen in 5 cases (1.6%), early origin of segment VI branch from right portal vein seen in 4 (1.3%) cases and quadrifurcation pattern seen in 3 cases (0.98%). Conclusion: Prevalence of portal vein variations is high on routine abdominal CT scans. Knowledge about branching patterns of these variations can be useful to reduce liver injury and complications during hepatic surgeries and interventions.

An unusual umbilical venous connection to a left posterior intercostal vein.

A foetal echocardiogram, in a 27-week foetus referred for cardiomegaly, demonstrated dextrocardia, absence of the ductus venosus, and an unrestricted unusual umbilical venous drainage to a left posterior intercostal vein, which continued to left hemiazygos vein and drained into the coronary sinus. Progressive cardiomegaly led to early delivery. To the best of our knowledge, no case with similar umbilical venous drainage has been previously reported.

Feasibility and Potential Significance of Prophylactic Ablation of the Major Ascending Tributaries in Endovenous Laser Ablation (EVLA) of the Great Saphenous Vein: A Case Series

Background Recurrent varicosities after endovascular laser ablation (EVLA) of the great saphenous vein (GSV) are frequently due to varicose transformed, initially unsealed major ascending tributaries of the saphenofemoral junction (SFJ). Preventive ablation of these veins, especially the anterior accessory saphenous vein, is discussed as an option, along with flush occlusion of the GSV. However, few related data exist to date. Methods A consecutive case series of 278 EVLA procedures of the GSV for primary varicosis in 213 patients between May and December 2019 was retrospectively reviewed. The ablations were performed with a 1470 nm dual-ring radial laser and always included flush occlusion of the GSV, and concomitant ablation of its highest ascending tributaries by additional cannulation and ablation when this seemed anatomically appropriate. The initial technical success, comprising occlusion of the GSV and its major tributaries, was set as the primary endpoint. Possible determinants were explored using downstream multiple logistic regression analysis. Results The early technical success was 92.8%, with the GSV occluded in 99.6% and the highest ascending SFJ tributary, if present, in 92.4%. Additional ablations of ascending tributaries were performed in 171 cases (61.5%), the latter being associated with success (OR 10.39; 95% CI [3.420–36.15]; p < 0.0001). Presence of anterior as opposed to posterior accessory saphenous vein was another positive predictor (OR 3.959; 95% CI [1.142–13,73]; p = 0.027), while a confluence of the tributary in the immediate proximity to the SFJ had a negative impact (OR 0.2253; 95% CI [0.05456–0.7681]; p = 0.0253). An endothermal heat-induced thrombosis (EHIT) ≥ grade 2 was observed in three cases (1.1%). Conclusions A co-treatment of the tributaries is feasible and could improve the technical success of EVLA if a prophylactic closure of these veins is desired, especially if their distance to the SFJ is short. Its effect on the recurrence rate needs further research.

Another Mention of Thebesian Veins in the Heart: Should It Be the Last?

Another Mention of Thebesian Veins in the Heart: Should It Be the Last?

‘Pseudo-septum’ Appearance in Septal Agenesis on Fetal MRI

Abstract Background Absence of the cavum septum pellucidum (CSP) can be associated with a wide spectrum of congenital brain malformations. It is necessary to describe the anatomic structures that can be mistaken for the CSP in cases of septal agenesis. Results We retrospectively studied MRI of 12 fetuses referred with suspicion of absent CSP on sonography. The structures simulating CSP in axial sections (Pseudo septum) are: volume averaging from the medial edge of the frontal lobes (lateral ventricles) in the anterior aspect, fornices in the mid and posterior aspect and internal cerebral veins in the postero-inferior aspect. Eleven out of the twelve suspected cases of absent CSP showed a false positive ‘pseudo-septum’ appearance in axial sections of fetal brain MRI. The absence of the ‘pseudo-septum’ was confirmed on coronal MRI sections of the fetal brain. Conclusion It is important to study the axial and coronal sections of the fetal brain for accurate diagnosis of septal agenesis.

Microvascular anatomy of the non-lobulated liver of adult Xenopus laevis: A scanning electron microscopic study of vascular casts.

The microvascular anatomy of the non‐lobulated liver of adult Xenopus laevis was studied by scanning electron microscopy of vascular corrosion casts. Hepatic portal veins and hepatic arteries entered hepatic lobes at the hiluses, hepatic veins left at these sites. Intraparenchymal, hepatic portal veins branched up to 10 times before terminal portal venules supplied liver sinusoids. Hepatic arteries closely followed portal vessels. Arteriolar side branches formed anastomoses with close by portal venules (arteriolar‐portal anastomoses; APAs), liver sinusoids (arteriolar‐sinusoidal anastomoses; ASAs), and peribiliary plexus vessels. Distally, hepatic arteries anastomosed with terminal portal venules having >100 μm in diameter. Liver sinusoids formed a dense three‐dimensional network displaying signs of non‐sprouting and sprouting angiogenesis evidenced by “holes” and blind ending tapering cast vascular structures (sprouts), respectively. Sinusoids drained via efferent hepatic veins. Right and left hepatic veins drained into the posterior caval vein. Locally, a dense honeycomb‐like 3D‐meshwork of resin structures was found around terminal portal venules and hepatic arteries. These networks were fed by hepatic arterioles and drained into adjacent terminal portal venules. As their morphologies differed significantly from sinusoids and they were found at sites where diffuse lymphoid tissue is described, we are convinced that they represent the vasculature of diffuse lymphoid tissue areas. Frequencies and diameter ratios of hepatic portal venules versus hepatic arterioles anastomosing with the former (APAs) implicate that the arterial supply contributes to the oxygenation of parenchymal and stromal cells rather than to a significant increase in blood flow towards hepatic sinusoids.