Anterior spinal artery aneurysm presenting with spinal subarachnoid hemorrhage in a case of polyarteritis nodosa

Polyarteritis nodosa is characterized by presence of aneurysms in the renal, hepatic and mesenteric vasculature, and less often by vascular abnormalities in the intracranial compartment. Spinal subarachnoid hemorrhage is a rare phenomenon that can be associated with inflammatory vasculopathies such as polyarteritis nodosa, but the link between aneurysm formation and spinal subarachnoid hemorrhage in polyarteritis nodosa is unclear. We describe a case of a patient with polyarteritis nodosa and spinal subarachnoid hemorrhage following rupture of an aneurysm of the anterior spinal artery. Following operative washout and decompression of the subarachnoid hemorrhage, spinal digital subtraction angiography was performed and revealed intimal contour irregularities, stenotic changes, and multiple small aneurysms in renal, hepatic, and bronchial arteries and some proximal spinal arteries, and, most notably, a pseudoaneurysm of the anterior spinal artery supplied directly by the artery of Adamkiewicz. Polyarteritis nodosa was subsequently diagnosed in light of these findings. Though previous cases have noted spinal subarachnoid hemorrhage in of the context of polyarteritis nodosa, we found no previously documented case of a definitive aneurysm of the anterior spinal artery in a case of polyarteritis nodosa documented on angiography. This case highlights the potential importance of monitoring for aneurysms of the spinal vasculature in cases of polyarteritis nodosa and in screening for vasculitides in cases of spinal subarachnoid hemorrhage. Future studies are needed to describe patterns of the specific anatomic localization and incidence of spinal artery aneurysms in polyarteritis nodosa.     

MRA of the Adamkiewicz artery: a preoperative study for thoracic aortic aneurysm

PURPOSE: The purpose of this work was to investigate the ability of MR angiography (MRA) to visualize the Adamkiewicz artery (AKA) as a preoperative study of thoracic aortic aneurysm to prevent ischemic injury of the spinal cord. METHOD: Twenty-six patients scheduled for surgical or endovascular stent-graft repair of thoracic aortic aneurysm were studied with a three-dimensional contrast MRA. Data acquisition was repeated two times following injection of Gd-DTPA. Source images were processed with multiplanar reconstruction and maximum intensity projection. RESULTS: The AKA was identified in 69% (18/26). In three patients, selective angiography of the intercostal artery confirmed the AKA at the same level and side predicted by MRA. The anterior spinal artery and the anterior medullary vein were observed in 50% (13/26) and 65% (17/26), respectively. CONCLUSION: Contrast MRA is a promising technique to visualize the AKA noninvasively as a preoperative evaluation of thoracic aortic aneurysms.     

MR angiography of the Adamkiewicz artery and anterior radiculomedullary vein: postmortem validation

SUMMARY: Spinal cord arteries and veins are difficult to visualize and distinguish by MR angiographic techniques because of their small sizes, similar spatial course, and close vascular anatomy. Contrast-enhanced MR angiography was demonstrated to dynamically resolve the Adamkiewicz artery from the anterior radiculomedullary vein in the thoracolumbar spinal cord. The location of the Adamkiewicz artery and the anterior radiculomedullary vein could be validated in the postmortem specimen of a thoracoabdominal aortic aneurysm patient.     

Asymptomatic aneurysm of the proximal right subclavian artery: a rare ultrasound diagnosis

True aneurysms of otherwise normal subclavian arteries are uncommon peripheral vascular anomalies. Most patients with subclavian artery aneurysms are symptomatic by presenting neurologic signs. We report a young woman who had an asymptomatic true aneurysm of the right subclavian artery assumed to be of congenital origin. This case is unique in that the aneurysm was in the extremely rare anatomic location of the right supraclavicular fossa between the origins of the right subclavian artery and the vertebral artery. Aneurysms of the right subclavian artery may represent a potential pitfall in conventional gray-scale ultrasound of the neck particularly the supraclavicular fossa. Differential diagnosis includes cervical cyst, pharyngo-esophageal diverticulum, vascular anomalies, struma, enlarged lymph node, as well benign or malignant neoplasms. Color duplex ultrasound should be performed as the method of choice for further analysis of suspected aneurysms. In this report the role of B-mode ultrasound and color duplex ultrasound is discussed in relation to digital subtraction- and MR angiography in confirmation of the diagnosis. Received: 5 January 1999; Revision received: 26 April 1999; Accepted: 18 June 1999     

脊髓前动脉损伤致脊髓缺血性损伤模型的MRI评价

目的：研究经脊髓前动脉损伤，致脊髓缺血性损伤模型的高场强MRI信号表现特征。方法：选用12只家犬经颈前手术入路，切断脊髓前动脉，经高场强MRI扫描，对照病理分析脊髓前动脉损伤后脊髓的MRI信号变化特征。结果：脊髓前动脉损伤后脊髓MRI表现出异常T2WI高信号，且出现在脊髓前动脉损伤节段的前2／3，多表现为一例受累及或偏向一例。结论：MRI能确定脊髓缺血性损伤的部位及信号特征。     

Normal anterior spinal arteries within the cervical region: high-spatial-resolution contrast-enhanced three-dimensional MR angiography

PURPOSE: To determine retrospectively whether the anterior spinal artery (ASA) is visualized in the cervical region with contrast material-enhanced high-spatial-resolution three-dimensional magnetic resonance (MR) angiography of the extracranial carotid and vertebral arteries. MATERIALS AND METHODS: The institutional research ethics committee approved this study and provided a waiver for informed consent. Data sets were evaluated in 50 consecutive patients referred for contrast-enhanced three-dimensional MR angiography of the carotid arteries (32 male and 18 female patients; age range, 15-80 years; mean age, 59 years). The ASA was defined as a linear area of high signal intensity that is seen anterior to the spinal cord in an arterial phase of enhancement and connects directly to a known arterial structure. If the linear area of high signal intensity was seen in the arterial phase but did not connect to a known arterial structure, it was considered a probable ASA. Venous enhancement was graded on a five-point scale (0-4) with grade 0 (no venous enhancement) or grade 1 (trace venous enhancement) considered to be in the arterial phase. RESULTS: The ASA was identified with certainty in 37 of 50 patients. A vessel visualized anterior to the spinal cord, which probably represented the ASA, was seen in another 11 of 50 patients. In 29 of 50 patients the vessel was visualized only on the full-volume maximum intensity projection (MIP) image. In the remainder of cases the artery was identified on operator-defined subvolume MIP images. Continuity between the vessel and the vertebrobasilar arterial structures was identified in 35 of 50 patients. The vessel was seen as a continuous structure throughout its length in 34 patients and appeared discontinuous in 14. Radiculomedullary feeders were identified in 24 of 50 patients. CONCLUSION: The normal cervical ASA was visualized in 48 of 50 of subjects with contrast-enhanced high-spatial-resolution three-dimensional MR angiography.     

Congenital absence of the internal carotid artery and the basilar artery with persistent trigeminal artery associated with coarctation of the aorta

We report a case of congenital absence of the cervical and petrous part of the left internal carotid artery, the middle and proximal part of the basilar artery, and the V4 segment of the left vertebral artery associated with a left persistent trigeminal artery and a coarctation of the aorta. The left cerebral vessels are supplied via the anterior communicating artery and the left persistent trigeminal artery. The coexisting coarctation of the aorta led to a subclavian steal phenomenon. The alteration of the cerebral hemodynamics has to be taken in consideration when performing cerebral angiography and surgical correction in such a case. Received: 16 November 1999; Revised: 20 April 2000; Accepted: 20 April 2000     

Bilateral occipital arteries arising from the thyrocervical trunks (ascending cervical artery-occipital artery anastomosis) diagnosed by magnetic resonance angiography

We herein report a case of bilateral occipital arteries (OAs) arising from the thyrocervical trunks (TCTs). The patient was a 34-year-old woman with suspected basilar artery aneurysm underwent magnetic resonance (MR) angiography of the head and neck region using a 3-Tesla scanner. Cranial MR angiography revealed no aneurysm. Cervical MR angiography showed bilateral OAs arising from the TCTs. The extremely hyperplastic ascending cervical artery (ACA) arose from the transverse cervical artery, and continued to the OA, bilaterally. The OA usually arises from the proximal external carotid artery and runs posterosuperiorly; rarely, it arises from the internal carotid artery or the vertebral artery. The variation in our patient is regarded as bilateral ACA-OA anastomosis. Only one case of the unilateral type of this variation has been reported, having been diagnosed during dissection. Before cervical arterial intervention or head and neck surgery, identification of OA variation is important. During the interpretation of cervical MR angiography findings, careful observation of the origin and course of the OA is required.     

Spinal arteriovenous malformations: advances in therapeutic embolization

Five patients with spinal arteriovenous malformations (AVMs) supplied at least in part by the anterior spinal artery were treated by embolization. Complete occlusion of the malformations was obtained without complication in all patients. Improved endovascular treatment of spinal AVMs is now possible with the use of calibrated particles of polyvinyl alcohol, serial digital subtraction angiography, and temporary balloon occlusion of the vertebral artery in cervical AVMs supplied by a pedicle arising from the vertebral artery.     

Topographic anatomy of paraclinoid carotid artery aneurysms: usefulness of MR angiographic source images

We evaluated the usefulness of magnetic resonance angiography (MRA) for showing the topography of paraclinoid carotid artery aneurysms in 27 patients with 30 paraclinoid aneurysms undergoing conventional angiography, three-dimensional time-of-flight MRA and surgery. The anatomy shown on the axial MRA source images was consistent with that found at surgery. The neck of the aneurysm could always be identified on the source images, while it could not be analysed exactly on conventional angiography in 3 cases (10 %). The optic nerves, including those displaced by the aneurysm, were recognised in all patients. The anterior clinoid process was shown as a low-intensity rim or area contiguous with the cortical bone. The source images were of great value in understanding the topography of paraclinoid carotid artery aneurysms. Received: 11 April 1996 Accepted: 12 August 1996     

Unruptured aneurysm with intramural thrombus is an unusual cause of spinal cord infarction: a case report

Infarction of the spinal cord is a rather rare occurrence. Paraparesis or quadriparesis with vibration and proprioceptive senses sparing are symptoms of anterior cord syndrome. Ischemic anterior cord syndrome can result from an obstruction of the anterior spinal artery or the Adamkiewicz Artery. Spinal infarction due to abdominal aortic aneurysm with intramural thrombosis is an extremely rare condition, because of its rarity, it presents a diagnostic difficulty to clinicians, which may result in an inaccurate or delayed diagnosis. We present a case of spontaneous spinal cord infarction due to a previously asymptomatic aortic aneurysm with intraluminal thrombus, with a review of the literature.     

Rotational vertebrobasilar insufficiency secondary to vertebral artery occlusion from fibrous band of the longus coli muscle

Summary Rotation-induced vertebrobasilar artery hypoperfusion causes transient ischemic attacks (TIAs), affecting the cerebellum, brainstem and spinal cord. When these symptoms occur transiently due to head movement, compression of the vertebral artery by an extraluminal lesion should be suspected. Cervical spondylotic spurs and anterior scalene muscle or deep cervical fascia are among the factors which can compress the vertebral artery. When symptoms of vertebrobasilar insufficiency occur with rotational head movement, subclavian angiography for visualization of the entire vertebral artery in both neutral and rotated head positions should be undertaken.     

Aneurysms of spinal arteries associated with intramedullary arteriovenous malformations. I. Angiographic and clinical aspects.

PURPOSE: To evaluate the nature of aneurysms of the spinal arteries, their relative frequency, and the risks associated with these lesions. METHODS: We retrospectively reviewed the spinal angiographic studies of 186 patients with spinal cord vascular malformations--70 intramedullary AVMs, 44 extra (peri) medullary AV fistulas, and 72 dural AV fistulas. RESULTS: Fifteen spinal artery aneurysms (SAs) in 14 out of 70 patients (20%) with an intramedullary AVM were discovered. No SAs were observed in the other types of spinal vascular malformations. The intramedullary AVMs with SAs were cervical in seven cases and thoracic in the other seven cases (one of the thoracic had two SAs). Fourteen SAs were located on a major feeding vessel to the associated intramedullary AVM (10 on the anterior spinal artery and four on a posterior spinal artery and only one SA was located remote from the AVM feeding vessels. This remote aneurysm was located on the intercostal artery feeding a vertebral angioma in a patient with metameric angiomatosis. Subarachnoid hemorrhage occurred in all cases of SA. The presence of a SA carried a statistically significant (P less than .05) increase in the risk of bleeding. CONCLUSIONS: Although increased blood flow seems to be an important factor in formation of these SAs associated with intramedullary AVMs, the role of a developmental vascular anomaly must be stressed: metameric angiomatosis was found in six out of the 14 patients (43%).     

MRI in presumed cervical anterior spinal artery territory infarcts

WE report the MRI findings in two patients with presumed cervical spinal cord infarcts in the anterior spinal artery territory. MRI revealed abnormal signal intensities and/or band-like enhancement in the anterior two-thirds of the cervical spinal cord, corresponding to the vascular territory of the anterior spinal artery. Clinically there was an anterior spinal cord syndrome.     

Value of CT angiography in the evaluation of a peripheral anterior inferior cerebellar artery aneurysm: case report.

We report a case of a peripheral anterior inferior cerebellar artery (AICA) aneurysm in a 66-year-old woman. Computed tomography angiography (CTA) demonstrated a saccular aneurysm in the left AICA. A subsequent vertebral digital subtraction angiography using our standard injection technique failed to demonstrate the aneurysm. However, the aneurysm was visualized on a follow-up injection performed with an increased contrast dose and injection rate. CTA proved to be critical in the detection of this aneurysm which could have been easily overlooked on a conventional angiogram.     

Traumatic false aneurysm of the subclavian artery treated by insertion of Memotherm stent

Traumatic aneurysms of the left subclavian artery and transverse cervical artery, subsequent to penetrating gunshot wound were diagnosed by angiography in 35-year-old patient. Subclavian artery aneurysm was treated by insertion of the Memotherm bare stent, whereas the false aneurysm of the transverse cervical artery was embolized with Gianturco's coils. The follow up examinations at 6 and 12 months showed good patency of subclavian artery.     

DSA全脑血管造影431例分析

目的:分析431例全脑血管造影,探讨颅内血管病变用DSA全脑血管造影的价值。材料和方法:92年至96年行DSA全脑血管造影431例。采用Seldinger技术,经股动脉穿刺置管行选择性或/和超选择性全脑血管造影。前交通及后交通动脉瘤经显微神经外科证实。结果:动脉瘤155例,血管畸形76例,占位性病变48例。颅内动脉瘤发生在大脑前动脉系统为42.58％,而前交通动脉瘤为大脑前动脉系统的74.24％。颅内动脉瘤为全脑血管造影阳性发现的首位,其次为血管畸形,颅内占位。本组阴性率为25.75％。结论:CT、MR发现颅内出血或血管畸形时,不一定全脑血管造影有阳性改变。     

25例脊髓动静脉畸形治疗

目的　探讨脊髓髓内动静脉畸形的栓塞方法。方法　 2 5例脊髓髓内血管畸形患者 ,均行血管内栓塞治疗 ,早期 4例在肋间动脉或腰动脉直接注射硬脑膜颗粒或PVA等 ,近期 9例将微导管插至供血动脉远端以PVA栓塞 ,1例先以NBCA栓塞供血动脉上的动脉瘤 ,再以Embosphere栓塞AVM。 7例以NBCA栓塞。 5例直接手术切除病灶 ,2例栓塞联合手术治疗。结果　 2 0例栓塞后造影证实 12例几乎完全栓塞 ,8例为大部分栓塞 ,经半年～ 2年随访 ,16例临床症状均有不同程度改善 ,4例临床症状无明显变化 ,均未出现出血症状。结论　对于髓内幼稚型和不能手术的团块型AVM ,血管内栓塞治疗为首选治疗。     

Bilateral tentorial subdural hematoma without subarachnoid hemorrhage secondary to anterior communicating artery aneurysm rupture: a case report and review of the literature

A case of acute subdural hematoma over the tentorium secondary to rupture of an anterior communicating artery aneurysm is reported. A 42-year-old female patient presented with acute-onset, severe bifrontal and retro-orbital headache. CT revealed only symmetric thickening of the tentorium. MR imaging revealed the presence of a 10-mm anterior communicating artery aneurysm, which was confirmed by digital subtraction angiography. The radiologic findings and possible mechanisms of this hemorrhage are discussed.     

Clinical and experimental investigation of pseudoaneurysm in the anterior communicating artery area on 3-dimensional time-of-flight cerebral magnetic resonance angiography

OBJECTIVE: To investigate the hemodynamic mechanism of pseudoaneurysm in the anterior communicating artery (AcoA) area in magnetic resonance (MR) angiography. METHODS: For the clinical study, a total of 62 patients who undertook digital subtraction angiography (DSA) because of the rupture of an aneurysm originating from a location other than the AcoA area were examined with MR angiography. The relation between signal defect at the AcoA in MR angiography and anatomic variation of the anterior cerebral artery (ACA) was evaluated. For the experimental study, MR angiography and DSA were performed on elastic silicon vascular phantoms with 2 different bifurcation angles (70 degrees and 140 degrees). Hemodynamic factors producing signal defects were evaluated, and the results were compared by computational fluid dynamics (CFD). RESULTS: In a clinical study, 21 of 62 patients had a hypogenetic A1 segment on either side of the ACA. Their MR angiography showed signal defects in the axilla area of the bifurcated AcoA complex in 14 patients, 7 of which could make the residual normal vessel seem to be an aneurysm. All the cases with an intact AcoA complex showed no signal defect. In an experimental study, MR angiography of vascular phantoms with broad-angle bifurcation (140 degrees) showed signal defects at the axilla areas of bifurcation, and these were shown as turbulent flow in DSA and CFD. Phantoms with narrow-angle bifurcation (70 degrees) did not show a significant signal defect, however. CONCLUSIONS: A hypoplastic A1 segment accompanying a broad bifurcation angle of the contralateral A1 segment may cause a pseudoaneurysm in MR angiography because of signal defect in the AcoA area.