【作者】 王一村；

【导师】 宋建星；

【作者基本信息】 第二军医大学 ， 外科学（专业学位）， 2013， 博士

【摘要】 背景自Wee和Joseph于1989年首次提出运用阴股沟皮瓣行阴道再造后,该项技术在近年来得到广泛的应用并逐渐成熟,临床适应症包括：生殖器官的重塑,会阴部创伤后的修复,会阴部肿瘤扩大切除术后的创面覆盖等。经过20余年的应用改良,该皮瓣依然存在术后皮瓣部分血运障碍、皮瓣外形臃肿,术后阴道口受皮瓣牵拉而裂开、变形等缺点。如何寻找到该皮瓣的明确供血动脉并给予精确定位成为了亟待解决的问题。目前临床对于皮瓣的研究多局限在二维空间,如课本、图片以及尸体解剖。近年来,随着计算机数字技术与影像学的有机结合,三维计算机技术在轴型皮瓣的血管研究应用中日益广泛。应用CT血管造影与三维重建相结合,明确定位轴型皮瓣的动脉血供,成为近年来国内外整形外科界研究的热点。阴股沟穿支皮瓣因其动脉穿支管径细微,且变异较多,临床应用其他穿支皮瓣为少,目前临床和基础研究仍较为薄弱。但是,阴股沟穿支皮瓣作为一个新近发展的皮瓣,伴随着社会的多元化发展,尤其是易性癖患者变性需求的增加,拥有广阔的应用前景。为了使阴股沟穿支皮瓣应用更加安全可靠,我们对会阴区的显微解剖进一步细化,并结合影像科的CT血管造影以及三维重建技术,尝试着研究出一种皮瓣穿支血管体表定位的方法,以求为阴股沟穿支皮瓣的安全应用提供有力的保障。目的对会阴区的阴股沟皮瓣行显微解剖,进一步了解阴股沟皮瓣的定位及走行,为影像学检查中定位血管提供理论基础。以320排螺旋CT血管造影和三维重建信息为指导,尝试在临床为阴股沟穿支皮瓣血管蒂的术前设计提供体表定位方法。观测该法对临床实验的帮助效果。方法一、显微解剖对10具(20侧)成人尸体的会阴区进行显微解剖学研究。10%福尔马林浸泡的成人尸体10具(20侧),经髂外动脉及桡动脉联合灌注红色乳胶,肉眼解剖,细微结构在10倍手术放大镜下观察,使用游标卡尺(精确0.2mm)测量。阴股沟皮瓣位于会阴部之间区域,上界过耻骨联合上缘水平约1cm,下界为两侧坐骨结节连线,内侧界为阴囊或大阴唇外侧缘,外侧界为股内侧皱襞,自阴囊或大阴唇外侧缘向大腿内上方延伸约6cm包括的范围。在标本会阴部上,模拟临床皮瓣设计方式,对皮瓣内包含的血管、神经进行观测。然后进行深部组织解剖,追踪血管、神经来源。对四支穿支动脉的管腔大小、走行、定位以及变异做进一步研究,并在尸体中找到伴行静脉及神经。将研究资料做统计学分析,为术中定位血管提供理论基础。二、CT血管造影及三维重建在2008年至2012年,选择40名使用阴股沟穿支皮瓣行会阴部修复手术或阴茎(阴道)再造术患者。随机分成实验组与对照组。实验组18名患者(其中2名因经济问题退出实验)均于术前3天行320排螺旋CT血管造影检查,通过软件对CT数据进行三维处理。通过软件对靶血管的多层面追踪,确定阴部外浅动脉会阴穿支的穿出位置,在三维图像中标记出来,同时运用软件的测量功能,分别测量出该点分别至髂前上棘和耻骨联合中点的距离。术前对患者进行体表定位：术前患者取截石位,运用直尺与骨盆测量尺结合三维图像中测量的数据进行体表定位。方法：将骨盆测量尺一端固定在髂前上棘A,以三维图像中测量的距离a确定另一端C’；将直尺的零刻度端固定在耻骨联合中点B,以三维图像中测量的距离b确定另一端C”；分别以两个距离a和b为半径画圆,可有两个交点,靠近会阴部的交点C即为该靶血管的体表定位点。以体表定位点C为血管蒂,标记出皮瓣所需的范围。根据标记范围行手术治疗。术前患者取截石位,运用直尺与骨盆测量尺结合三维图像中测量的数据进行体表定位。三、手术方法全麻成功后患者取截石位,导尿。沿标记范围切开皮肤,分离至深筋膜浅层,层厚约1-1.5厘米。由皮瓣远端向近端掀起,切断并结扎闭孔动脉前皮支穿支及阴囊(唇)后动脉外侧穿支。皮瓣内侧剥离至标记点1-1.5厘米即可。保留蒂部,完整分离。皮瓣成形后,根据患者的需求行阴道再造术或会阴部肿瘤切除术后覆盖。缝合创面后,无菌辅料包扎。持续导尿。结果一、解剖会阴区动脉血供由两侧腹股沟向下延续,分布至大腿与会阴之间的皱襞、阴囊(唇)外侧及股内侧无毛区。该区动脉血液供应充足,有阴部外浅动脉会阴支及腹股沟支,闭孔动脉前皮支,阴囊(唇)后动脉的外侧支,股内侧的主要动脉支,旋股内侧动脉的皮支,以及来自阴部内动脉支的肛动脉(直肠下动脉)等,并且位置均比较恒定,变异较少。尤其以阴部外浅动脉穿支最为恒定。二、CTA及三维重建CT血管造影及三维重建：原始的CT资料由软件转化重建后,在3D图片上可以清晰的显示靶动脉的位置、走行及变异。可清晰显示穿支动脉由上级动脉穿出并穿过筋膜组织到达皮肤组织。可与软组织、骨性组织同时显影,进一步明确定位。通过在3D图片上的标记位置,测量出该标记点至髂前上棘的平均距离左侧为176.4毫米,右侧为176.6毫米；至耻骨联合中点的平均距离左侧为64.8毫米,右侧为64.8毫米。三、手术结果患者的随访时间8-22个月,平均13.2个月。手术：实验组平均皮瓣分离时间为35.22±5.59分钟,对照组平均手术时间54.15+4.51分钟,手术时间明显缩短(P<0.0001)。实验组术后发生皮瓣局部感觉丧失2例,未出现局部皮瓣血运障碍；对照组出现皮瓣局部感觉丧失4例,局部皮瓣血运障碍5例。实验组并发症发生率明显降低(P<0.05)。上述并发症患者术后6个月通过保守治疗均得以恢复。通过体格检查及患者口述,证明患者对皮瓣外形及功能满意。结论320排螺旋CT血管造影及三维重建为阴股沟皮瓣的术前体表定位提供了可靠的帮助,该无创技术为穿支血管的定位提供了准确的影像学信息,并指导临床手术。是一种安全、准确的体表定位方法。如何减少定位时的误差问题,是进一步研究的重点。CTA作为一种临床常用检查手段能够精确的预先判断穿支血管的管径、位置、走行,方便术者预先设定好管径最大、肌肉段较短、位置最佳,使“靶向”穿支血管皮瓣成为可能。其三维重建的结构可以多色彩任意组合,整体显示血管与周围骨骼、肌肉的毗邻关系。但是CTA作为穿支皮瓣的术前检查在国内广泛使用仍存在限制：首先是费用较高,作为一项辅助检查,无法大范围使用。其次是辐射量和造影剂的问题,尤其是对造影过敏的患者无法使用。以上问题亟待在将来的进一步研究中解决。更多还原

【Abstract】 BackgroundVarious surgical techniques have been proposed for perineal reconstruction, one of which is the use of cutaneous thigh flap based on pudendal neurovascular bundle (Pudendal thigh perforator flap, PTPF). A perforator flap can be defined as a free flap consisting of skin, subcutaneous fat and the nourishing by transmuscular perforator vessels which is freed by a careful dissection from the underlying muscle. It was first described and successfully performed for perineal reconstuction by Wee and Joseph in1989, based on their neurovascular studies of the upper thigh, medial groin, and perineum in female fresh cadavers. Superiority of this technique was apparent as it was simple, reliable, less flap loss, flap retained sensory innervations and was able to hide the scars in the groin crease. In female, there was less incidence of postoperative vaginal stenosis and natural angle of intercourse. Bai Jin et al in2008further characterized our knowledge of perforating vessels, venous returns and the cutaneous nerve innervations in the perineum through their microdissection fresh cadaver study which enabled a better designing of PTPF. A more precise knowledge of the anatomy of the perforating vessels in the perineum have reduced the overall rate of vascular complications in the flap reconstruction of perineum, however, there are individual anatomical variations and its implication in flap loss is still a big fear for reconstructive surgeons.Precise location and anatomy of the perforating vessels in PTPF is essential for flap survival. Traditional clinical training on flap anatomy is based on textbooks,2dimensional pictures and cadavers does help reducing this risk, however, a more precise three dimensional visualization of the anatomy of PTPF and its neurovascular components of the individual surgical candidate is desirable and the use of CT angiography (320-row multidetector computed tomography angiography) and3D reconstruction technology to design the PTPF’s pedicle, such as described in this article, makes it possible.ObjectThe objective of this study is to determine the quantity, position, and caliber of perforating vessels in the perineum, and to provide ananatomic basis for designing perineal perforator flaps. To provide a body surface position method to help design pudental thigh perforator flap’s pedicle by using320-row multidetector competed tomography angiography and3D reconstruction.MethodTen adult cadavers (20sides) fixed in10%formalin were dissected in this study. Red latex was infused from the external iliac artery and radial artery, using a modified lead oxide-gelatin infusion technique. Cadavers were dissected with an operating microscope (×10).Structures of artery and venous were measured using a sliding caliper (accurate to0.2mm). The border of the examined area was:inferior, the imaginary line between the2ischiadic tuberosities; superior,3cm above the superior margin of pubic symphysis; medial, the lateral margin of the scrotum (labium); and lateral, interfemusplica.Patient data of our department were reviewed retrospectively. We have compared two groups who received perineum reconstruction using PTPF between2008-2012. Case group consisted of18patients who had perineum reconstruction using PTPF, with the aid of preoperative localization of superficial external pudendal artery using contrast-enhanced CT angiography and then3D image reconstruction. Indications for their surgeries were pseudohermaphroditism (2females and2male), congenital vaginal atresia (21females), and perineum tumors (9males-2lymphangioma,3basal cell carcinoma and2Paget disease,6females-1lymphangioma,2basal cell carcinoma,3Paget disease), divided into2groups randomly. The mean patient age was30.4years and the mean height was164.4cm. Four of the pseudohermaphrodite patients had endocrinological disorders and they were taking regular medications. All male patients were smokers but all female patients were non-smokers. Patients were instructed to quit smoking for at least2weeks preoperatively. Control group consisted of20patients who had perineum reconstruction using PTPF without the aid of the above imaging technology.Computer tomography angiographies (320-row MDCT scanner, Aquilion ONE, Toshiba Medical Systems, Otawara, Japan) were performed using a standardized protocol in our Radiology Department. The CT Scanner has320detector rows (each0.5mm wide) with a rotation time of350ms (with a temporal resolution of175ms for half reconstruction). A single rotation of the gantry could obtain320slices of CT images from a16cm volume area without a helical scan. Therefore, sub-second times grants MDCT to capture a high-definition three-dimensional (3D)-CT image. In addition, the intermittent scan during contrast infusion allows the reconstruction of dynamic3D-CT images. Scanning was performed during the intravenous administration of80-90ml of the contrast material (Ultravist370, Bayer Schering, Germany) using an automated injector device at a rate of4.0ml s-1. The imaging voltage and current were controlled at120kV, and350mA, and gantry rotation time was0.5s. The generated images were transferred into a computer and were then interpreted using Vitrea software (Vitreasoft, Vitreastation, Tokyo, Japan) to regenerate the final dynamic3D Volume-rendering image. All cross sectional images were displayed in sagittal, coronal, transverse planes and these were reconstructed to create the3D map.Information of the vessels obtained from angiographic images was also used for pre-operative planning. The point at which the perineum perforators branched from the superficial external pudendal artery were chosen to be the rotating point of the flap and its distances from the anterior superior iliac spine and the mid-pubic symphysis were also measured. This rotation point was marked on the body surface and the PTPF was designed and fashioned.Standard axial PTPF was designed with flap centering on the superficial pudendal artery. Point at which the superficial pudendal artery branched was localised by using the measurement of its distance from the ASIS and Midpoint pubic symphisis using a straight ruler and the pelvic measurement feet. The common ruler’s zero point was fixed on the middle of pubic symphysis with the length of measurement above, and the pelvic measurement feet’s zero point was fixed on the anterior superior iliac spine with the length of measurement above, and the other side of each ruler intersected on one point.Surgery was performed with patients in the lithotomy position. The sizes of the flaps ranged from9×4cm to15×5cm, depending on the size of the defect and the length of the required pedicle. Following the skin incision, flap was carefully elevated with particular care to not damage the axial blood supply, the perforators of superior pudendal artery. The flap was observed for10minutes to ascertain the adequacy of its blood supply and it is then positioned to cover the surgical defect.Patients received follow up observation up to8months after the surgery.ResultThere were4constant perforating arteries in the perineum:inguinal and perineal perforating branches of the superficial external pudendal artery, a perforating branch of the lateral branch of the posterior scrotal (pudendal) artery, and a perforating branch of the anterior cutaneous branch of theobturator artery. These perforating arteries and accompanying veins macthed up with each other and formed the upper, middle, and lower parts of the vascular anastomosis in deep fascia above the adductor wall. There were4 important cutaneous nerves in the region originating from the following nerves:the genitofemoral nerve, ilioinguinal nerve, posterior scrotum (labium) major nerve, and rami perineal esnervicutaneifemorisposterioris.The branch originated from the superficial external pudendal artery, and traveled medially. The branch typically originated from the inferior side of the great saphenous vein, and extended horizontally. It gave rise to many willow-like branches to supply the upper perineal region. After entering the scrotum (labium) from the lateral upper side, the branch turned inferiorly. The length of the artery was5.37±0.16cm. It supplied the upper one third of the scrotum (labium). The main stem anastomosed with the medial and posterior scrotal (labial) arteries.All patients were followed up (mean13.2months; range8to22months), and the flap sensation was assessed by self questionnaires and at the time of physical examinations. All38flaps were deemed viable at the completion of surgery. All patients in the case group recovered except2patient loss of flap sensation. In control group5patients had partial flap necrosis (both healed by secondary intention) and4patients had a temporary loss of sensation of the flap (spontaneously recovered after6months). Compare to control group, case group took on average11.54minutes less operative time, which could be confirmed by the non-paired t test with significance level<0.01(Table1). Besides, comparison of between the two groups also proved better postoperation satisfactions from the case group, as indicated by lower rates of sense loss, partial necrosis and complications (p<0.05).ConclusionThe perineum has abundant blood supply, venous return, and innervation. Due to its covert location and manuevor ability, perforator flaps from this region are good sources of donor tissue for perineal reconstruction.Preoperative assessment of the PTPF’s vascular anatomy using320-row MDCT angiography is a useful non-invasive procedure that allows surgeons to accurately visualize the vascular anatomy of PTPF and in creating a surgical plan.更多还原