anatomical variants
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H-INDEX

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2022 ◽  
pp. 197140092110674
Author(s):  
Kamran Munawar ◽  
Eytan Raz ◽  
Seena Dehkharghani ◽  
Girish M Fatterpekar ◽  
Tobias K Block ◽  
...  

StarVIBE is a 3D gradient-echo sequence with a radial, stack-of-stars acquisition having spatial resolution and tissue contrast. With newer sequences, it is important to be familiar with sequence tissue contrasts and appearance of anatomical variants. We evaluated 450 patients utilizing this sequence; 35 patients demonstrated fluffy “cotton wool” enhancement at the internal auditory canal fundus without clear pathology. We favor this represents anatomic neurovascular enhancement that StarVIBE is sensitive to and is a touch-me-not finding.


2021 ◽  
pp. 61-92
Author(s):  
Lalitha Shankar ◽  
Kate Evans ◽  
Thomas R. Marotta ◽  
Eugene Yu ◽  
Michael Hawke ◽  
...  

Author(s):  
Paweł Szaro ◽  
Khaldun Ghali Gataa ◽  
Bogdan Ciszek

Abstract Purpose The spring ligament complex (SL) is the chief static stabilizer of the medial longitudinal foot arch. The occurrence of normal anatomical variants may influence radiological diagnostics and surgical treatment. The aim of this study was to evaluate anatomical variants of the part of SL located inferior to the talar head (i-SL), medioplantar oblique ligament (MPO) and inferoplantar longitudinal ligament (IPL). Methods We included 220 MRI examinations of the ankle performed on a 3.0 T engine. Only patients with a normal SL were included. Two musculoskeletal radiologists assessed the examinations and Cohen’s kappa was used to assess agreement. Differences between groups were assessed using the chi-squared test; p < 0.05 was considered as significant. The final decision was made by consensus. Results Most commonly, i-SL was composed of the two ligaments IPL and MPO n = 167 (75.9%); in this group, bifid ligaments occurred in 19.2%, most commonly in the MPO. A branch to the os cuboideum was seen in n = 17 (10.2%). Three ligaments were seen in n = 52 (23.6%). In this group, bifid ligaments occurred in 13.5%; most commonly, the IPL was bifid and a branch to the os cuboideum was noted in n = 6 (11.5%). In one case, n = 1 (0.04%), we identified MPO, IPL and two accessory ligaments. No significant relationship was noted between the number of ligaments, the presence of bifid ligaments and side or gender (p > 0.05). Conclusion. More than two aligaments were seen in 24.1% of examined cases, the most common variant was the presence of MPO, IPL and one accessory ligament.


2021 ◽  
Author(s):  
Zhongshan Gou ◽  
Xinxin Yan ◽  
Baojuan Sun ◽  
Jie Zhang ◽  
Hongmei Liu ◽  
...  

Aim: To investigate the types, associated anomalies and postnatal outcomes of fetal hepatic venous system (HVS) variants by ultrasound in China.Material and methods: A large-scale and prospective investigation of HVS variants for low-risk singleton pregnant women was performed in three academic tertiary referral care centers in China. Ultrasound imaging wasused for the identification and follow-up of anatomical variants. Follow-up was conducted once every four weeks prenatally and every two months postnatally, mainly concerned on the adverse events that may appear.Results: There were 20848 cases with anatomical variants of fetal HVS identified from 46179 candidates during the study period. Following the anatomical position of variants occurring, four main divisions were present: main portal vein variants (17.9%), intrahepatic portal vein variants (21.30%), intrahepatic persistent right umbilical vein (0.27%) and hepatic vein variants (5.67%). In the fetal period, the pregnancy of all cases was normally continued, except that the pregnancy of two cases, which were associated with multiple anomalies and were terminated by their parents. After birth, approximately 99.47% of the cases with isolated variants orbeing associated no clinic significant anomalies were normally alive. Approximately 0.50% cases were associated with simple ventricular septum defect or tetralogy of Fallot and further treatment was needed.Conclusion: The anatomical variants of fetal HVS may appear as numerical, morphological or positional variants of MPV, intrahepatic PV branches, intrahepatic PRUV and HVs. The majority of cases are isolated or their associated anomalies are not clinically significant and have normal lifeafter birth.


Author(s):  
Karolina Brzegowy ◽  
Bernard Solewski ◽  
Paweł Brzegowy ◽  
Agata Musiał ◽  
Tadeusz Popiela ◽  
...  

Introduction : In acute ischemic stroke, collateral circulation determines tissue fate and treatment results. The aim of this study was to evaluate the role of anatomical variations of the Circle of Willis (CoW) in formation of cerebral collateral blood flow in patients with acute M1 occlusion. Methods : This study was a retrospective assessment of radiological examinations of patients with stroke due to middle cerebral artery M1 segment occlusion. All patients underwent mechanical thrombectomy from January 2015 until March 2021. The anatomy of the CoW was assessed on initial CT‐angiography and DSA. CTA was utilized to grade cranial collateral vasculature status and cortical vein opacification score (COVES). Non‐contrast CT scans and ASPECTS scores (using RAPID software) were used to determine the ischemic area. Results : A total of 100 patients were included in the analysis (58 females and 42 males, mean age: 71.6 +/‐ 13.9). We classified the anatomy of the CoW according to its continuity as a full circle. Patients with fully continuous CoW (n = 19) had worse COVES scores than those with CoW incomplete at both anterior and posterior portion (n = 9) (89% vs 68% with COVES 0–2, p = 0.179). No statistically significant results were found when comparing the enhancement of collaterals between these two groups (p = 0.390). The COVES scores were similar for patients with complete and incomplete anterior portions of CoW (77% vs 80% with COVES 0–2, p = 0.812). Patients with incomplete posterior portions of CoW had lower COVES scores than those with complete (80% vs 67% with COVES 0–2, p = 0.206). No statistically significant differences were discovered when comparing different types of the posterior communicating artery (adult, transitional and fetal). Analysis of ischemic areas determined as ASPECTS scores pre‐ and post‐thrombectomy yielded no significant differences between any of the groups. Conclusions : Although certain variants of the CoW have been reported to increase the risk of ischemic stroke, our results show that the anatomy of CoW has no large effect on collateral blood flow during acute M1 occlusion. We presume that the greater role is played by pial arterioles than anatomical variants of major cerebral arteries in cerebral collateral circulation formation. Detailed knowledge about the factors that influence collateral blood flow is crucial as it may aid in identification of patients prone to worse outcomes of ischemic stroke. Anatomical variants of CoW do not play a major role in formation of cerebral collaterals.


Author(s):  
Bernard Solewski ◽  
Karolina Brzegowy ◽  
Paweł Brzegowy ◽  
Agata Musiał ◽  
Tadeusz Popiela ◽  
...  

Introduction : This study aimed to determine what anatomical variants of the Circle of Willis (CoW) and the middle cerebral artery(MCA) are observed in patients with acute M1 occlusion and whether their prevalence differs from that described as “normal” in anatomy textbooks. Methods : We have performed a retrospective assessment of radiological examinations of patients with stroke due to middle cerebral artery M1 segment occlusion. All patients underwent mechanical thrombectomy from January 2015 until March 2021. The anatomy of the CoW was assessed on initial CT‐angiography and DSA. Branches of the MCA were observed on control DSA after recanalization. Results : A total of 100 patients were included in the analysis (58 females and 42 males, mean age: 71.6 +/‐ 13.9). Fully complete CoW was observed in 19% of patients. A total of 10% of patients had an incomplete anterior portion of CoW. In the incomplete anterior portion subgroup, the most common variation was the absence of anterior communicating artery (6% of total hemispheres), followed by the absence of one A1 (3% of total hemispheres). An incomplete posterior portion of CoW was identified in 79% of the patients. The absence of posterior communicating artery (PCoA) was observed in 59 patients. Sixteen patients had adult‐type PCoA, 3 patients had transitional‐type PCoA and 21 patients had fetal‐type posterior cerebral artery (PCA). In the subgroup of patients with fetal‐type posterior circle, 5 patients had no P1 segment of PCA. Anterior temporal branch of MCA was observed in 45% of the patients. Middle cerebral artery bifurcation was found in 80% of hemispheres, and trifurcation in 20%. In the bifurcation subgroup, 26% of MCAs had a dominating upper branch and 18% had a dominating lower branch. A duplicate MCA was observed in one hemisphere. Conclusions : In comparison to normal anatomy described in anatomy textbooks, the population of patients suffering from ischemic stroke due to M1 occlusion had a lower proportion of complete and closed CoW. A foetal type PCoA was observed to be prevalent (21%) in patients suffering from acute M1 occlusion. Detailed anatomical knowledge of anatomical variants of CoW in patients undergoing mechanical thrombectomy is essential for clinicians performing intravascular interventions and may aid procedure planning.


2021 ◽  
Vol 27 (3) ◽  
pp. 55-68
Author(s):  
Svetla Dineva ◽  
Milko Stoyanov ◽  
Aneliya Partenova ◽  
Boyan Kunev ◽  
Victoria Stoyanova ◽  
...  

Anatomical variants of pulmonary venous drainage in the left atrium are often found. Divergent results have been reported on the impact of variant anatomy on atrial fi brillation (AF) recurrence after catheter ablation. We aimed to study the frequency of different anatomical variants of pulmonary venous drainage and their relationship with documented recurrences of AF after ablation. Material and methods: A retrospective study of patients with AF in whom radiofrequency pulmonary vein isolation was done after previously performed cardiac contrast-enhanced multidetector computed tomography. Clinical and procedural characteristics, type and frequency of anatomical variants of the veno-atrial junction and their association with AF recurrences were studied. Results: One hundred seventy-seven patients (112 men, 63.3%) with AF were studied, of which 148 (83.6%) with paroxysmal AF. Variant anatomy was found in 91 patients (51.4%). In 20.9% there was a common left trunk, in 23.2% – more or less than two right-sided veins, and in 7.3% – variations for both right and left veins. No differences in clinical and procedural characteristics were found between the groups with normal and variant anatomy. Recurrences of AF and their association with pulmonary venous anatomy were studied in 104 patients with follow-up ≥ 3 months. No signifi cant relation was found between the presence of variant anatomy and AF recurrences within the blinding period after ablation, OR = 0.864, 95% CI = 0.397 – 1.88, p = 0.843, nor afterwards, OR = 1.12, 95% CI = 0.5 – 2.5, p = 0.839. Cox regression analysis showed no differences in AF recurrence-free survival regardless of the anatomical variant of pulmonary venous drainage, HR = 1.09, 95% CI = 0.58 – 2.05, p = 0.779. Conclusion: In this local population of patients with AF, the incidence of variant pulmonary venous drainage is just over 50%. No association was found between variant anatomy and the rate of AF recurrences after fi rst pulmonary vein isolation.


Aorta ◽  
2021 ◽  
Author(s):  
Umberto G. Rossi ◽  
Anna M. Ierardi ◽  
Maurizio Cariati

AbstractWe report the case of a 73-year-old male who underwent abdominal multidetector computed tomography with vascular reconstruction that highlighted a congenital variant of iliac arteries. Iliac artery anatomical variants are exceedingly rare and only a few cases have been reported in the literature.


2021 ◽  
Vol 14 (4) ◽  
pp. 4-18
Author(s):  
Aleksandr A. Kuprin ◽  
Viktor Y. Malyuga ◽  
Timur A. Britvin ◽  
Ivan O. Abuladze

Background. The thesis «thyroid surgery is the surgery of the recurrent laryngeal nerve», which was defined in the XX ­century, remains relevant to this day. Thus, despite the use of modern scientific and technological achievements, vocal cord paresis is diagnosed on average in 9.8% patients after thyroid and parathyroid surgery.According to many authors, the main problem which a surgeon encounters is a difficult and sometimes individual anatomy of the recurrent laryngeal nerve. For example, in one study authors identified 28 variants of relationships between the ­recurrent laryngeal nerve and the inferior thyroid artery. In a recent meta-analysis, it was noted that the frequency of extralaryngeal branching remains underestimated and reaches 73% of cases. Anatomical variants of the recurrent laryngeal nerve or its thin branches, which have not been noticed in time, can lead to inevitable consequences — to nerve injury and a laryngeal dysfunctions, and if anatomical features are not detected on both sides — to a tragedy.Aim. The aim of this study is to determine anatomical variants of the extralaryngeal branches of the recurrent laryngeal nerve and their frequency in autopsy case series.Materials and methods. 46 (100%) recurrent laryngeal nerves were dissected in 23 cadavers. Their path was traced, their relationships with the inferior thyroid artery were determined, and the extralaryngeal branches of the recurrent laryngeal nerve were identified.Results. Few extralaryngeal branches of the recurrent laryngeal nerve were identified during dissection: tracheoesophageal branches, laryngeal branches, aberrant branches. Tracheoesophageal branches were determined in all cadavers. In 37 (80.4%) cases the recurrent laryngeal nerve had got two or more extralaryngeal laryngeal branches. In 6 (13.0%) cases aberrant branches were presented.The inferior thyroid artery was detected in 42 (91.3%) cases. The vessel was in close location with the recurrent laryngeal nerve, forming a neuro-arterial chiasm. In 39.1% of cases the recurrent laryngeal nerve was located between the branches of the inferior thyroid artery, in 39.1% of cases — deeper than the artery, and in 10.9% of cases — more superficial than the artery.Conclusion. The variable anatomical configuration of the recurrent laryngeal nerve inevitably causes difficulties during intraoperative nerve dissection. Tardy identification of these anatomical features can lead to the injury of nerves or its branches, which determines the amount of postoperative vocal cord paresis.


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