Perforating arteries

Abstract: We investigated the extraosseous and intraosseous arterial anatomy of the human adult elbow. Twenty-two fresh adult cadaveric upper extremities were studied with a technique of combined India-ink and latex injection followed by chemical debridement. The intraosseous vascularity of twelve extremities was then evaluated with a rapid Spalteholz clearing technique. Our findings demonstrated consistent patterns of extraosseous and intraosseous vascular anatomy, which were organized into three vascular arcades: medial, lateral, and posterior. The medial arcade was formed by the superior and inferior ulnar collateral arteries and the posterior ulnar recurrent artery. The lateral arcade was formed by the radial and middle collateral, radial recurrent, and interosseous recurrent arteries. The posterior arcade was formed by the medial and lateral arcades and the middle collateral artery. The intraosseous circulation of the elbow, which was segmental in organization, appeared to be dependent on the local blood supply. The capitellum and the lateral aspect of the trochlea were supplied by posterior perforating vessels arising from the radial recurrent, radial collateral, and interosseous recurrent arteries. The medial aspect of the trochlea was supplied by a circumferential vascular ring originating from the inferior ulnar collateral artery. Watershed areas were apparent between the blood supplies to the medial and lateral aspects of the distal end of the humerus. The olecranon was richly supplied by vessels coursing along its medial aspect from the posterior ulnar recurrent artery and along its lateral aspect from the interosseous recurrent artery. The radial head had a dual extraosseous blood supply from a single branch of the radial recurrent artery, which supplied the head directly, and from additional vessels from both the radial and the interosseous recurrent artery, which penetrated the capsular insertion at the neck of the radius. CLINICAL RELEVANCE: Our findings demonstrate that arterial contributions to the intraosseous circulation of the elbow are more specific than previously appreciated. The intraosseous circulation of the elbow is derived mainly from perforating vessels that arise from neighboring extraosseous arteries. These perforating arteries may be damaged by trauma or by extensile dissection during reconstruction of the elbow. An understanding of the extraosseous and intraosseous circulation of the elbow may help to avoid iatrogenic injury to the intraosseous circulation.

Abstract: OBJECTIVE: Perforating arteries are commonly involved during the surgical dissection and clipping of intracranial aneurysms. Occlusion of perforating arteries is responsible for ischemic infarction and poor outcome. The goal of this study is to describe the usefulness of near-infrared indocyanine green videoangiography (ICGA) for the intraoperative assessment of blood flow in perforating arteries that are visible in the surgical field during clipping of intracranial aneurysms. In addition, we analyzed the incidence of perforating vessels involved during the aneurysm surgery and the incidence of ischemic infarct caused by compromised small arteries. METHODS: Sixty patients with 64 aneurysms were surgically treated and prospectively included in this study. Intraoperative ICGA was performed using a surgical microscope (Carl Zeiss Co., Oberkochen, Germany) with integrated ICGA technology. The presence and involvement of perforating arteries were analyzed in the microsurgical field during surgical dissection and clip application. Assessment of vascular patency after clipping was also investigated. Only those small arteries that were not visible on preoperative digital subtraction angiography were considered for analysis. RESULTS: The ICGA was able to visualize flow in all patients in whom perforating vessels were found in the microscope field. Among 36 patients whose perforating vessels were visible on ICGA, 11 (30%) presented a close relation between the aneurysm and perforating arteries. In one (9%) of these 11 patients, ICGA showed occlusion of a P1 perforating artery after clip application, which led to immediate correction of the clip confirmed by immediate reestablishment of flow visible with ICGA without clinical consequences. Four patients (6.7%) presented with postoperative perforating artery infarct, three of whom had perforating arteries that were not visible or distant from the aneurysm. CONCLUSION: The involvement of perforating arteries during clip application for aneurysm occlusion is a usual finding. Intraoperative ICGA may provide visual information with regard to the patency of these small vessels.

Abstract: Perivascular (Virchow-Robin) spaces normally surround perforating arteries that enter the medial temporal lobes, corpus striatum, and thalamus. The high soft-tissue sensitivity of magnetic resonance (MR) imaging allows for the frequent detection of such cerebrospinal fluid (CSF)-filled spaces. Especially on axial images, these CSF-filled perivascular spaces may be confused with pathologic lesions, such a lacunar infarcts. Postmortem brain specimens demonstrate the anatomy of perivascular spaces around perforating arteries. Orthogonal images in the living patient help confirm this anatomic relationship. The characteristic CSF signal patterns from these foci are further evidence of their anatomic identification and true benign nature.