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Seven AVMs系列--脑室及脑室周围动静脉畸形的显微外科解剖 脑室体部AVM手术解剖及切除策略--Seven AVMs系列 （阅读本文前建议先回顾前2篇--点击前面链接即可） The Ventricular Atrium AVM---脑室三角部AVM The atrial AVM resides in the atrium, posterior and lateral to the ventricular body (Fig. 14.6). Callosal and ventricular body AVMs are midline, whereas atrial and temporal horn AVMs have laterality. The C-shaped structures that wrap around the thalamus (i.e., caudate nucleus, crus of fornix, and choroid plexus) deviate laterally as they course around its posterior surface toward the temporal horn, and atrial AVMs are in the middle zone between the ventricular body and temporal horn. They were the second most common ventricular/periventricular subtype and accounted for around 20%. Atrial AVMs are supplied by the lPChA, which enters the ventricle at the atrial portion of the choroidal fissure. Collateral connections within the choroid plexus enable the AChA to supply these AVMs from below via the temporal horn’s plexus, and the mPChA to supply them from anteriorly via the ventricular body’s plexus. Atrial AVMs drain through the medial and lateral AtrVs that course through the choroidal fissure of the atrium and connect to the ICV and BVR, respectively. Atrial AVMs sit on the pulvinar surface, which has no eloquence, but the crus of the fornix lies medial to the choroid plexus. Atrial AVMs differ from thalamic AVMs that may protrude into the atrium, but are deeply embedded in the thalamus, extend close to the posterior limb of the internal capsule, are supplied by thalamoperforators rather than choroidal arteries, and are exquisitely eloquent. 三角部AVM居于侧脑室三角部，在侧脑室体的后方和外侧(图14.6)。胼胝体和脑室体AVM是中线的，而三角部和颞角AVM是外侧的。包绕丘脑的C型结构（如尾状核、胼胝体和脉络丛）随着绕过丘脑的后表面而偏向外侧颞角方向，三角部AVM位于脑室体和颞角的中间。它们是次常见的脑室/脑室周围的亚型，占20%上下。三角部AVM由lPChA供血，后者在脉络裂三角部进入脑室。脉络丛内的侧支连结，使AChA能够通过颞角的脉络丛从下方、mPChA能够通过脑室体的脉络丛从前方，分别给这些AVM供血。三角部AVM通过内侧和外侧AtrV引流。后者沿三角部脉络裂穿行，分别与ICV和BVR连接。三角部AVM位于丘脑枕面，与语言功能无关，但是穹窿脚位于脉络丛内侧。三角部AVM与可以凸入三角部的丘脑AVM不同，后者深深嵌入丘脑，扩大接近内囊后肢，由丘脑穿支而非脉络丛动脉供血，与语言功能有很大关系。 Fig. 14.6 The ventricular atrium AVM, axial cross-sectional view. This AVM is located in the atrium of the lateral ventricle, supplied by the lPChA, and drained by atrial veins (medial to the ICV and lateral to the BVR). 图14.6 脑室三角部AVM，轴位切面观。该AVM位于侧脑室三角部，由IPChA供血，三角部静脉引流（内侧汇入ICV，外侧汇入BVR）。 Ventricular Atrium AVM Resection---脑室三角部AVM切除术 Atrial AVMs are resected through a parietal craniotomy and superior parietal lobule approach (Fig. 14.16). The patient is positioned laterally with the head turned toward the floor to bring the parietal convexity uppermost in the field. A trajectory through the superior parietal lobule (SPL) to the atrium is selected using frameless stereotactic navigation. Alternatively, an entry point is selected that is between 6 and 9 cm above the inion and between 3 and 5 cm lateral to the midline. A C-shaped scalp incision is centered over this entry point, and a parietal craniotomy flap is elevated (step 1). A transcortical corridor is opened through the SPL to the atrium (step 2). The atrial portion of the choroidal fissure lies between the crus of the fornix posteriorly and the pulvinar and caudate body anteriorly. Draining veins include AtrV (medial and lateral), ChorV (superior and inferior), and posterior CauV, which all converge on the choroidal fissure and collect in the ICV and BVR en route to the VoG (step 3). This venous anatomy as well as arterial supply from the lPChA (step 4) is accessed by opening the choroidal fissure. Like the transchoroidal fissure dissection into velum inter positum, the tela choroidea is opened on the fornix side of the choroid plexus (tenia fornicis) to avoid the thalamus. The arterialized vein is identified as it exits the choroidal fissure, and lPChA feeders are coagulated at the AVM’s inferior margin (step 5). Circumdissection has no parenchymal planes and is parallel, albeit deep (step 6). Widening the choroidal fissure expands the view of the draining atrial veins, the AChA input from the temporal horn, and the normal PCA along its ambient segment. There may be some thalamoperforator supply on the pulvinar surface or lLSA on the caudate body that is interrupted at the ependyma (step 7). Although not strictly eloquent, atrial AVMs are adjacent to the posterior thalamus, caudate body, and crus of fornix (Fig. 14.17). 脑室三角部AVM切除是通过顶部开颅、顶上小叶入路（图14.16）。病人取侧卧位，头转向地面，使顶部凸面位于术野最高点。用无框架立体定向导航选择从顶上小叶（SPL）到三角部的路径。或者，在枕骨隆突上6-9cm、中线外侧3-5cm选择进入点。以此点为中心行C-型头皮切口，掀起顶部颅骨瓣（第1步）。打开经SPL到三角部的经皮层通道（第2步）。脉络裂的三角部部分位于后方的穹窿脚和前方的丘脑枕及尾状核体之间。引流静脉包括AtrV（内侧和外侧）、ChoV（上方和下方）和后CauV，均在脉络裂汇合进入ICV和BVR，然后入VoG（第3步）。通过打开脉络裂，可完成这些静脉和发自IPChA的供血动脉的解剖（第4步）。就像经脉络裂切开进入中间帆一样，在脉络丛的穹窿侧（穹窿带）打开脉络膜，避开丘脑。在出脉络裂处辨认动脉化的静脉，在AVM下缘电凝来自IPChA的供血血管（第6步）。扩宽脉络裂以扩大视野，看到引流的三角部静脉、来自颞角的AChA供血动脉和环池段的正常PCA。可能有一些丘脑枕面的丘脑穿支供血血管或者尾状核体上的ILSA在室管膜处切断（第7步）。虽然没有严格意义上的语言功能，但是三角部AVM与后丘脑、尾状核体和穹窿脚相邻（图14.17）。
Fig. 14.16 Resection strategy for ventricular atrium AVMs. (a) Step 1, exposing the AVM with a semicircular scalp incision (top inset, dashed line), parietal craniotomy (top inset, solid line), and a superior parietal lobule approach (bottom inset) that traverses parietal cortex to enter the atrium (surgeon’s view). (b) AVM box showing supply from the lateral posterior choroidal artery, drainage to the medial and lateral atrial veins, and proximity to the thalamus, caudate nucleus, and fornix. (c) Step 2, entering the atrium with a transcortical approach through the SPL; step 3, identifying draining veins as they converge on the choroidal fissure; step 4, identifying arterial supply from the lPChA and AChA; and step 5, interrupting the inferior front along the choroidal fissure (surgeon’s view). (d) Step 6, circumdissection is intraventricular without parenchymal planes (axial cross-sectional view). (e) Step 7, mobilizing the AVM laterally to divide deep supply from thalamoperforators on the pulvinar surface and lenticulostriates on the caudate surface, and also visualize atrial veins as they exit the choroidal fissure (spherical scoop, surgeon’s view). 图14.16 脑室三角部AVM的切除策略。(a)第1步，半圆形头皮切口（上嵌入图，虚线）、顶部开颅（上嵌入图，实线），经顶部皮质进入三角部的顶上小叶入路（底部嵌入图）显露AVM（术者视角观）。(b)AVM盒示意来自脉络膜后外侧动脉供血，引流入内侧和外侧三角部静脉，邻近丘脑、尾状核和穹窿。(c)第2步，通过SPL经皮质入路进入三角部；第3步，在脉络裂汇合处辨认引流静脉；第4步，辨认来自IPChA和AChA的供血动脉；第5步，沿脉络裂切断这些动脉的下面（术者视角观）。(d)第6步，环形切除是在没有脑实质的脑室内平面进行 (轴位断面观)。(e)第7步，将AVM移向外侧，以切断来自丘脑枕面的丘脑穿支和尾状核表面上的豆纹动脉的供血，也看清出脉络裂时的三角部静脉(球形头，术者视角)。 Fig. 14.17 This 3-year-old boy presented with intraventricular hemorrhage from a right atrial AVM (supplemented Spetzler-Martin grade 5: S2V1E0/A1B0C1), supplied by the AChA and lLSA and drained by MedAtrV and ICV [right ICA angiogram, (a) lateral and (b) anteroposterior views]. (c) A right parietal craniotomy exposed the superior parietal lobule (lateral position, midline horizontal, nose to the left). (d) A transcortical approach through the SPL accessed the atrium of the lateral ventricle, where the choroid plexus was cauterized adjacent to an enlarged AChA. 图14.17 该3岁男孩，表现为来自一右侧三角部AVM的脑室内出血(补充 Spetzler-Martin分级5级: S2V1E0/A1B0C1), 供血来自AChA和lLSA，由MedAtrV和ICV引流[右侧ICA造影 (a)侧位，(b)前后位]，(c) 右顶开颅，显露顶上小叶（侧卧位，中线水平位，鼻朝左)。(d)通过SPL经皮质入路，到侧脑室三角部，在这里电凝与扩张的AChA邻近的脉络丛。 Fig. 14.17 (continued) (e) The AChA was followed from the temporal horn to the undersurface of the thalamus to the AVM, where it was interrupted. (f) The draining vein was visualized on the posterior thalamus in the superior atrium. (g) After cauterizing small transthalamic feeding arteries on the thalamic surface, the draining vein darkened and the AVM was removed. (h) This transcortical corridor was long and narrow, but well tolerated clinically. 图14.17(续) (e)沿来自颞角的AChA到丘脑下表面到AVM，在此将AChA切断。(f)在上三角部后丘脑上可见引流静脉。(g) 电凝在丘脑表面的小的横过丘脑的供血动脉后，引流静脉变黑，切除AVM。(h)此经皮质的通道长且窄，但临床耐受较好。 未完待续---
原著作者: Michael T. Lawton, MD 编译者：河南省人民医院神经外科，张长远； 审校：河南省人民医院神经外科，史锡文教授。 |
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