Anomalous atlantoaxial portions of vertebral and posterior inferior cerebellar arteries

Summary In a review of the vertebral angiograms of 300 patients free from disease at the craniovertebral junction, we found atlantoaxial arterial anomalies in 2,3%. These were: 2 cases in which the vertebral artery ran in the spinal canal below C1, 3 cases of duplication of the vertebral artery above and below C1, and 2 cases of origin of the posterior inferior cerebellar artery at C2. Although these arteries ran in the spinal canal between C1 and C2, they never encroached upon the posterior third of the canal. From the survey of another 21 patients having bony abnormalities at the craniovertebral junction, the first type of arterial anomaly described above was seen in 4 patients and associated with failure of segmentation of the embryonic sclerotome such as occipitalization of the atlas or Klippel-Feil syndrome. It is possible to relate the development of these anomalous vessels to malarrangement of the embryonic segmental arteries. Our results indicate that one must be cautious with lateral C1/2 puncture or surgical exposure of the region.     

Congenital defects of the posterior arch of the atlas: a report of seven cases including an affected mother and son.

PURPOSETo describe our experience with congenital anomalies of the posterior arch of the atlas, with a review and classification of these defects and a note on their clinical significance.METHODSWe report six children and one adult, the mother of one of the children, with an anomalous posterior arch of the atlas. The diagnosis was made on lateral films of the neck. Three patients also had axial CT of the cervical spine.RESULTSThe anomalies encountered in the seven patients were absence of the posterior arch of the atlas (four patients), bilateral clefts (two patients), and unilateral cleft (one patient). In three patients the anomaly was discovered as an incidental asymptomatic finding; three other patients presented with transient neck pain or transient neurologic symptoms after head and neck trauma, and one patient (an adult woman) described neck symptoms of 1-year duration.CONCLUSIONSOn the basis of these seven cases we conclude that congenital defects of the posterior arch of the atlas may be discovered as incidental asymptomatic findings, but symptoms occurring after trauma to the head and neck or spontaneously also may be encountered.     

Hemangiomas of the head,neck, and chest with associated vascular and brain anomalies: a complex neurocutaneous syndrome.

PURPOSETo describe the vascular and nonvascular intracranial and extracranial anomalies associated with hemangiomas and vascular malformations of the face, neck, and/or chest.METHODSSeventeen patients had a physical examination and imaging studies consisting of one or more of the following: pneumoencephalography, conventional carotid and vertebral arteriography, CT, MR imaging, and MR angiography.RESULTSConventional arteriography revealed persistence of the trigeminal artery in 5 cases, absence of internal or external carotid and/or vertebral arteries in 11 cases, persistence of intervertebral arteries in 1 case, deformities of the aortic arch in 3 cases, and anomalies of the intracranial arteries in 3 cases. MR angiography revealed persistence of the trigeminal artery in 1 case in which conventional arteriography failed to show the malformation, and permitted visualization of narrowing of the intracranial arteries. CT and MR imaging showed a cerebellar anomaly in 8 cases and cerebral cortical dysplasia with cerebral hemispheric hypoplasia in 1 case. Vascular and nonvascular anomalies appeared ipsilateral to the external vascular abnormalities in most cases.CONCLUSIONThis study demonstrates the association of cutaneous angiomas with anomalies affecting intracranial and extracranial arteries, the cerebellum, and, less frequently, the cerebral hemispheres and aortic arch. This association constitutes a relatively frequent neurocutaneous disorder, which we call the cutaneous hemangioma-vascular complex syndrome.     

Congenital anomalies of coronary arteries in complex congenital heart disease: Diagnosis and analysis with dual-source CT

BackgroundCongenital heart diseases (CHDs) are sometimes associated with coronary artery anomalies (CAAs). Accurate preoperative evaluation of coronary artery anatomy is essential for successful surgical repair of complex CHD.ObjectiveThe aim of this study was to evaluate the incidence of congenital CAAs in patients with complex CHD at dual-source CT.MethodsFour hundred seventeen consecutive patients with complex CHD underwent contrast-enhanced cardiac CT angiography. The results were retrospectively analyzed, including the types and incidences of CAAs in various forms of complex CHD. Each patient was analyzed independently by 2 experienced cardiovascular radiologists. Image quality of coronary arteries was assessed on a 5-point scale with 2 or less being nondiagnostic.ResultsThirty-five of 417 studies were nondiagnostic (8.39%). Sixty-three cases of CAA (15.11%) were detected by anomalous ostia and coronary arteries. CAA was involved in 6 of 108 patients with tetralogy of Fallot (5.56%), 18 of 84 patients with double outlet right ventricle (21.43%), 11 of 97 patients with pulmonary artery atresia (11.34%), 7 of 36 patients with transposition of the great arteries (22.22%), 15 of 41 patients with single ventricle (36.59%), 4 of 12 patients with truncus arteriosus/aortopulmonary window (33.33%), and 2 of 39 patients with interruption of the aortic arch/coarctation of the aorta (5.13%). Twenty of these were accompanied with an anomalous coronary course (31.74%).ConclusionPatients with complex CHD have a higher prevalence of CAAs, which should be considered before surgery. Dual-source CT is an effective technique to visualize and evaluate complex CHD.     

Parallel and spiral flow patterns of vertebral artery contributions to the basilar artery.

PURPOSETo demonstrate that the in vivo flow from individual vertebral arteries can be imaged and tracked in the basilar artery by use of saturation planes with three-dimensional time of flight MR angiography.METHODSTwenty volunteers were studied with intracranial three-dimensional time of flight angiography MR. The MR angiography was repeated with saturation of the individual vertebral arteries. Flow voids and signal intensity within the basilar and posterior cerebral arteries were evaluated for flow patterns.RESULTSOf 15 volunteers with a "normal" vertebrobasilar anatomy, 80% demonstrated a pattern of flow within the basilar artery in which the contributing vertebral components remained ipisilateral. This pattern was called "parallel." A "spiral" pattern of rotation of the contributing vertebral components was found in 20% of studies. The inflow to the posterior cerebral arteries could be identified from specific vertebral contributions and was related to the size-dominance of the vertebral artery.CONCLUSIONThere is nonadmixture of vertebral artery flows of variable duration within the basilar artery; at least two patterns of flow can be described within the basilar artery. The method presented is a simple technique for determining vertebral artery flow components with routine software and without secondary data manipulation.     

应用DSA诊断椎-基底动脉变异

目的探讨椎基底动脉变异的种类和发生率及DSA影像学特征,提高对椎基底动脉变异临床意义的认识。方法对6432例患者均进行全脑血管进行造影,对全脑血管造影的DSA图像资料进行回顾性分析,得出椎基底动脉变异的发生率及变异血管合并其他血管病变的情况。结果发生椎动脉起源变异272例患者278支椎动脉,检出率为4.3%,其中左椎动脉起源异常270支(4.2%),右椎动脉起源异常8支;左椎动脉起源异常中,258支直接起自主动脉弓,2例为双起源椎动脉,4支起自颈内动脉,6支起自左锁骨下动脉根部。8支右椎动脉起源异常中,2支直接起源于右颈总动脉,2支起自右颈内动脉动脉,2例为双起源椎动脉,2支直接起自头臂干动脉。141例椎基底动脉成窗(2.19%);61支小脑后下动脉起自颅外段位置较低部位。11例永久性原始三叉动脉。另外,有9例变异结构的远端或近端伴发动脉瘤、2例伴发动静脉畸形。7例出现与成窗结构供血区相一致的一过性脑缺血症状,其中2例出现经成窗结构远端供血部位的脑梗塞,1例出现经双起源椎动脉供血部位的脑梗塞。结论脑血管DSA可以清晰显示椎基底动脉变异的位置、形态、毗邻关系及有无伴发其他血管性病变;掌握椎基底动脉变异的DSA影像学表现及血流动力学特征,对脑血管病的明确诊断及手术和介入治疗方案的制定具有重要临床意义。     

Aortic arch variation: a unique case with anomalous origin of both vertebral arteries as additional branches of the aortic arch distal to left subclavian artery

We present the case of bilateral anomalous origin of both vertebral arteries (VAs) in a 20-year-old male patient who presented for routine contrast-enhanced CT follow-up examination of the chest. Contrast-enhanced CT revealed abnormal origins of both the VAs from the aortic arch distal to the origin of the left subclavian artery. Following this, CT angiography was performed, which confirmed the findings. To our knowledge, this is the first report of anomalous origins of both VAs beyond the origin of the left subclavian artery. The possible embryonic mechanism and the clinical importance of this variant is also reviewed.     

Duplicate origin of left vertebral artery

Summary A verified case of duplicate origin of the left vertebral artery in association with a large aneurysm arising from the aortic arch immediately distal to the left subclavian artery is presented. An anomalous left vertebral artery arises directly from the aortic arch between the left common carotid and subclavian arteries, and joins with the normal left vertebral artery in the transverse foramen of the fifth cervical vertebra.     

Abnormal course of the vertebral artery at the craniovertebral junction in patients with Down syndrome visualized by three-dimensional CT angiography

INTRODUCTION: We determined the incidence of vertebral artery (VA) anomalies at the craniovertebral junction (CVJ) in patients with Down syndrome, and characterized the VA anomalies. METHODS: The course of the VA in 46 consecutive patients who were due to undergo posterior arthrodesis surgery at the CVJ were evaluated by three-dimensional CT angiography (3DCTA). Included were five patients with Down syndrome who suffered from myelopathy due to atlantoaxial subluxation. All five patients with Down syndrome also had a simultaneous congenital skeletal anomaly, either os odontoideum or ossiculum terminale. RESULTS: Of the five patients with Down syndrome, three had VA anomalies at the CVJ, two had fenestration and one had a persistent first intersegmental artery. Of the other 41 patients without Down syndrome, five had VA anomalies at the CVJ. The incidence of VA anomalies at the CVJ was much higher in patients with Down syndrome than in those without Down syndrome. CONCLUSION: In planning surgery in patients with Down syndrome with symptomatic atlantoaxial subluxation and a congenital skeletal anomaly at the CVJ, we should consider the possible presence of VA anomalies. Preoperative 3DCTA allows us to precisely identify an anomalous VA and evaluate the possible risk of intraoperative VA injury in advance.     

Anatomical associations and radiological characteristics of Scimitar syndrome on CT and MR

PurposeTo report the anatomical associations and radiological characteristics of Scimitar syndrome on CT and MR.Materials and methodsRetrospective review of the medical records between February 2001 and February 2016 was performed. To identify patients, radiological reports were queried for “Scimitar” or “partial anomalous pulmonary venous return.” Patients with radiological findings of Scimitar syndrome were included. Patients without cross-sectional imaging were excluded. Patients' demographics, radiologic images, and medical notes were reviewed. Two radiologists re-read the available imaging studies. Images were reviewed for Scimitar syndrome confirmation, number and location of Scimitar vein drainage, number of lobes drained by the Scimitar vein, and right pulmonary artery and lung hypoplasia. In addition, the number of pulmonary veins draining into the left atrium, left sided anomalous pulmonary veins, congenital heart disease, aortic arch anomalies, cardiac dextroposition, right ventricular enlargement, pulmonary artery enlargement, and elevated QP:QS ratios were identified. Other associated anomalies including the presence of an anomalous feeding artery and pulmonary sequestration, abnormal lobar pattern, localized bronchiectasis, horseshoe lung, accessory diaphragm, diaphragmatic hernia, vertebral anomalies, and genitourinary tract anomalies were reviewed.ResultsSixteen patients (3 males, 13 females; mean age 39.5 years, range 14 days–72 years) with confirmed Scimitar syndrome on CT and MR imaging were identified. The Scimitar vein drained to the infra-diaphragmatic inferior vena cava (IVC) in ten patients and to the supra-diaphragmatic IVC in six patients. The most common associated anomalies were right ventricle enlargement (93.3%), variant lobar pattern of the right lung (92.9%), enlarged pulmonary arteries (60%), and cardiac dextroposition (50%).ConclusionRecognizing the radiologic characteristics and anatomical associations of Scimitar syndrome is important as features of the primary condition and associated anomalies may have implications in surgical management.     

Congenital anomalies of coronary arteries: Diagnosis with 64 slice multidetector CT

Objective

Congenital coronary artery anomalies are generally incidental, uncommon and asymptomatic. Some can cause severe potentially life threatening symptoms. The common mode of studying the coronary arteries is Conventional Coronary Angiogram. ECG-gated-multidetector CT is a non invasive modality. The objective of our study was to identify rare congenital coronary artery anomalies and discuss their clinical significance.

Material and methods

A total number of 900 MDCT coronary angiograms were carried out at our institution between the period of April 2006 and October 2010. Patients with coronary artery anomaly constituted the subject of study.

Results

The incidence of anomalous anatomical origin and course of the coronary arteries in our study was 1.55%. Hemodynamical significance was seen in five patients. 3 cases of single coronary artery originating from right coronary sinus were seen. 1 case of anomalous left coronary artery arising from main pulmonary artery was seen. 4 cases of anomalous RCA arising from left aortic cusp, 6 cases of absent LMCA with separate origin of LAD and LCX were seen.

Conclusion

Multidetector row CT is a noninvasive modality in cardiac imaging. It provides superior resolution of coronary tree and its variant. No projectional vascular overlap is seen. Various postprocessing techniques outclass catheter angiography imaging. Definition of ostia and proximal course of the coronary arteries by Multidetector CT is better than catheter angiography.     

椎动脉变异的多层螺旋CT血管成像诊断

目的研究多层螺旋CT血管成像(MSCTA)对椎动脉变异的诊断价值,并探讨其临床意义。方法回顾性分析MSCTA诊断的椎动脉变异32例。结果椎动脉起源变异7例,椎动脉行径变异(进入第5、4或第3横突孔)22例,单侧椎动脉先天性狭窄15例,椎动脉颈段双分支1例,椎动脉窗式变异1例,一侧椎动脉未汇合入基底动脉即单干椎动脉形成基底动脉2例。结论MSCTA是一种无创性诊断椎动脉变异的影像学检查方法。     

Difficulties in examination of the origin of the vertebral artery by duplex and colour-coded Doppler sonography: anatomical considerations

Despite progress in ultrasonographic techniques visualisation of the origin of the vertebral arteries, particularly the left, by duplex and colour Doppler imaging, still poses a problem in a significant number of patients. In anatomical and radiological studies we demonstrated an anomalous origin in 6%, the left vertebral artery originating directly from the aorta in most cases. The origin from the subclavian artery was found to be posterior in 44% and inferior in 6%. The V1 segment of the vertebral artery (from its origin to the entry into the foramen transversarium) was tortuous in 47% of cases. These anatomical variants and variations in the course of the vessel contribute to the nonvisualisation of the origin of the vertebral artery by duplex and colour Doppler imaging. With respect to tortuosities technical modifications for better visualisation are suggested and possible implications for surgery are discussed.     

Cervical collaterals may protect against stroke after blunt vertebral artery injury

The incidence of ischemic stroke reported after blunt vertebral artery injury is lower than that reported after blunt carotid artery injury. Unlike the carotid arteries, the vertebral arteries receive collateral blood flow through ascending cervical branches in addition to a convergent arterial supply with the contralateral vertebral artery. We hypothesize that the incidence of stroke after vertebral artery injury is less than after carotid artery injury in part because of reconstitution of vertebral arteries by cervical collaterals. A retrospective blinded interpretation of angiographic studies in 46 patients with blunt vertebral injury was performed to assess for presence and grade of vertebral artery injury and for the presence of reconstitution of the vessel via cervical collaterals. Follow-up CT scans from the same patients were evaluated for the presence of posterior circulation strokes. There were 55 injured vertebral arteries in the 46 patients, of whom 8 experienced posterior fossa strokes. Two-tailed Fisher exact probability test evaluating the hypothesis that patients with vertebral artery collaterals were less likely to experience posterior fossa strokes reached significance, p < 0.05. Of patients with occlusive (grades IV and V) injuries, those with collateral vessels were significantly less likely to experience posterior fossa strokes (p < 0.01). This result may be considered when weighing the potential risks and benefits of antiplatelet or anticoagulation therapy in patients with occlusive blunt vertebral artery injury.     

Vertebral artery variations at the C1–2 level diagnosed by magnetic resonance angiography

Introduction  

The craniovertebral junction is clinically important. The vertebral artery (VA) in its several variations runs within this area. We report the prevalence of these VA variations on magnetic resonance angiography (MRA).     

16层螺旋CT触发技术在颈部动脉CTA中的临床应用

目的:探讨16层螺旋CT团注追踪触发技术在颈部动脉CT血管成像(CTA)中的应用价值。方法:9例志愿者行主动脉弓同层动态增强扫描,利用获得的主动脉弓时间-密度曲线(TDC),寻求触发技术的理论阈值。将28例患者随机分为4组(触发阈值分别为110 HU1、40 HU1、70 HU2、00 HU),采用16层螺旋CT结合触发技术行颈部动脉CTA检查,探讨CTA触发技术的最佳应用阈值。结果:阈值140 HU组(参照组),颈总动脉、颈内动脉及椎动脉全程强化明显(CT值188~262 HU),而颈内静脉强化不明显,动静脉密度差别大,3D后处理显示的动脉图像清晰。阈值110 HU组,椎动脉起始处CT值较低(106 HU);阈值170 HU及200 HU组,C1及C5椎体平面颈内静脉的密度明显升高(>150 HU),与参照组比较差异有极显著性意义(P<0.01)。结论:16层螺旋CT血管成像中触发技术结合最佳触发阈值可较好地显示颈总动脉、颈内动脉及椎动脉;对比剂注射流率4.0 ml/s,触发阈值为140 HU时的图像质量较好。     

Uncommon congenital extracardiac vascular anomalies detected on MSCT (Multi-Slice Computed Tomography) aortic angiography with 64-multislice technology

Objective

The purpose of this study was to evaluate the role of CT angiography in different encountered congenital vascular anomalies of pediatric age groups using 64 multislice CT scanner.

Subjective and methods

Through one year, a total of 15 patients having congenital extracardiac anomalies were encountered from those attending big trauma and emergency center and were studied in this work. Each patient’s parent was thoroughly asked about the detailed clinical history after reviewing the referring imaging request and laboratory findings. Exclusion criteria for CT were as follows: previous allergic reactions to iodine contrast media and severe renal insufficiency. CT examination was performed using 64 multislice CT machine.

Results

CTA examination was performed in a total of 15 patients. The age of the patients was ranging from 2 days to 14 yrs and 5 cases were females. Four cases came with cyanosis; one case came with follow up after operation for transposition of great arteries, while the remaining cases were suffering from medical problems such as respiratory distress or hypertension. Aortic arch hypoplasia, right sided aortic arch with mirror image or with aberrant left subclavian artery, hypoplastic left pulmonary artery with left sided aortic arch and aberrant right subclavian artery, hypoplastic left heart chambers, retrotracheal left pulmonary artery with patent ductus arteriosus (PDA), right superior partial anomalous pulmonary venous drainage (PAPVD) with ASD sinus venosum, postoperative assessment of transposition of great arteries (TGA), fibromuscular dysplasia involving the renal and common iliac arteries, and bilateral double renal arteries with ectopic right kidney were the different extracardiac vascular anomalies encountered in this work.

Conclusion

CTA provides an excellent means to detect a number of extracardiac vascular anomalies and allows accurate and fast noninvasive characterization of extracardiac vascular anatomy. It is a helpful tool in establishing the primary diagnosis, defining anatomic landmarks and relationships, identifying vascular anomalies and helping in postoperative follow-up.     

Computed Tomography Angiography Prediction of Successful Trasnscatheter Embolization for Type II Endoleak of Endovascular Abdominal Aortic Aneurysm Repair

PurposeTo evaluate the utility of computed tomography (CT) angiography before transarterial embolization (TAE) in predicting TAE’s technical success for type II endoleaks (T2ELs).Materials and MethodsFifty-eight patients (mean age, 74.4 years; range, 46–89 years) who underwent attempted TAE for T2EL from July 2014 to August 2019 and underwent CT angiography before the procedure were included. Each CT angiography result was assessed for a feeding artery that was traceable over its entire course from either the superior mesenteric artery or the internal iliac artery to the endoleak cavity. TAE was performed using coils and was considered technically successful if embolization of the endoleak cavity and feeding artery was performed. The technical success rates were compared between patients with and without traceable feeding arteries.ResultsA fully traceable feeding artery supplying 75% (44/59) of endoleaks in the cohort was identified. TAE was technically successful in 95% (42/44) of these cases but only in 13% (2/15) of the cases without a fully traceable feeding artery (P < .001). When the inferior mesenteric artery was the feeding artery, it was always fully traceable, and TAE was technically successful in 100% (33/33) of the cases. When a lumbar artery was the feeding artery, it was fully traceable in only 42% (11/26) of the cases. When the lumbar artery was not fully traceable, TAE was technically successful in only 13% (2/15) of the cases.ConclusionsThe traceability of a feeding artery over its entire course to an endoleak cavity using CT angiography was associated with TAE’s technical success. Lumbar feeding arteries were less likely to be fully traceable. TAE’s high failure rate when the feeding artery was not fully traceable suggests that translumbar embolization can be considered as an initial approach for theses patients.     

Hangman's fracture: radiologic assessment in 27 cases

Traumatic spondylolisthesis of C-2, frequently referred to as the hangman's fracture, is typically regarded as a hyperextension injury with rare neurologic sequelae by virtue of decompression of the neural canal. The authors retrospectively evaluated their radiographic experience with this injury in 27 patients over a 24-month period. Lateral cervical spine studies and computed tomography (CT) scans (21 patients) were analyzed. CT studies provided better delineation of the fracture in all 21 patients and significant additional information in five patients (24%). Seven patients (26%) suffered initial neurologic sequelae in association with the C-2 injury. Nine patients had additional sites of fracture, including seven with associated C-1 ring disruption (26%). Extension of the fracture line into the transverse vertebral artery foramen led to vertebral artery injury and cerebellar embolization in one patient. Angiography may be necessary to detect intimal injury to the vertebral arteries when the fracture extends through the transverse foramina and to indicate the need for anticoagulation when clinically feasible.     

Doppler sonography in basilar artery occlusion

Summary We have investigated 6,972 patients with directional continuous-wave Doppler sonography within the last three and a half years, and have derived criteria for the sonographic diagnosis of basilar artery occlusion or tight stenosis in conjunction with 1,071 retrograde brachial angiograms. By sonographic patterns, we have suspected obstruction of the basilar artery or of both distal vertebral arteries in nine cases. Either bilateral sonographic silence or the absence of a diastolic flow component of the vertebral arteries served as criteria in the sonographic evaluation. Angiography of the vertebro-basilar system, performed in eight cases, showed near or complete occlusion in the distal vertebrals or in the proximal basilar artery. Degrees of stenosis less than an 80 percent reduction in lumen diameter could not be detected sonographically. Two further basilar artery occlusions were detected by means of angiography despite negative Doppler sonography: one of these patients showed an extensive collateral circulation between the posterior inferior and the superior cerebellar arteries, and one patient had an occlusion only of the middle and rostral thirds of the basilar artery, the proximal third and the anterior inferior cerebellar arteries being widely patent. Thus, we believe that directional CW Doppler sonography is very useful in the diagnosis of near or complete occlusion of both distal vertebral arteries or of the proximal basilar artery.