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MRI在克罗恩病肛瘘活动性评价与随诊中的研究进展
杨米扬 戚婉 石荣

Cite this article as: YANG M Y, QI W, SHI R. Research progress of MRI in activity evaluation and follow-up of perianal fistulizing Crohn's disease[J]. Chin J Magn Reson Imaging, 2023, 14(4): 181-187.本文引用格式:杨米扬, 戚婉, 石荣. MRI在克罗恩病肛瘘活动性评价与随诊中的研究进展[J]. 磁共振成像, 2023, 14(4): 181-187. DOI:10.12015/issn.1674-8034.2023.04.032.


[摘要] 克罗恩病(Crohn's disease, CD)是一种病因不明的慢性非特异性炎症性肠病。CD肛瘘(perianal fistulizing CD, pfCD)作为CD最常见的并发症,常发生在成人和儿童CD中。随着医学技术的不断发展,多种辅助检查方法应运而生,如内镜、瘘管造影、麻醉下探查、腔内超声、MRI等皆可辅助诊断。其中MRI具有无创、快速、准确等特点,已经成为pfCD影像学诊断的金标准。本文就盆腔MRI在pfCD的诊断价值、鉴别诊断与疗效评估进行综述。同时考虑到pfCD的复杂性,本文还探讨了CD的MRI炎症活动评分、影像学指标和基于MRI的新技术,以期为pfCD患者诊治策略的进一步优化提供理论依据。
[Abstract] Crohn's disease (CD) is a chronic nonspecific inflammatory bowel disease of unknown etiology. Perianal fistulizing Crohn's disease (pfCD) is the most common complication of CD and frequently occurs in both adults and children. With the continuous development of medical technology, a variety of imaging-assisted examination techniques came into being, such as endoscopy, fistula angiography, examination under anesthesia, endoscopic ultrasonography, MRI etc., can assist in diagnosis. MRI has become the gold standard for the imaging diagnosis of pfCD due to its non-invasive, rapid and accurate characteristics. This paper reviews the diagnostic value, differential diagnosis and efficacy evaluation of pelvic MRI in pfCD. Considering the complexity of pfCD, this paper also discussed the MRI inflammatory activity score, imaging indicators and new MRI based technology of CD, in order to provide theoretical basis for further optimization of diagnosis and treatment strategies for patients with pfCD.
[关键词] 克罗恩病、肛瘘、肛周疾病、磁共振成像、炎症活动指标;诊断
[Keywords] Crohn's disease;perianal fistula;perianal disease;magnetic resonance imaging;inflammatory activity index;diagnosis

杨米扬 1   戚婉 2*   石荣 3  

1 福建中医药大学第一临床医学院,福州 350122

2 福建中医药大学附属人民医院放射科,福州 350004

3 福建中医药大学附属人民医院肛肠科,福州 350004

通信作者:戚婉,E-mail:742860555@qq.com

作者贡献声明:杨米扬参与本研究的构思与设计,起草和撰写稿件,获取、分析或解释本研究的文献;戚婉参与本研究的构思与设计,起草论文和对稿件重要内容进行了修改;石荣参与论文数据的收集、整理、分析与解释本研究的文献,对稿件重要内容进行了修改,获得了国家自然科学基金的资助;全体作者都同意发表最后的修改稿,同意对本研究的所有方面负责,确保本研究的准确性和诚信。


基金项目: 国家自然科学基金 81973852
收稿日期:2022-11-23
接受日期:2023-04-11
中图分类号:R445.2  R657.16 
文献标识码:A
DOI: 10.12015/issn.1674-8034.2023.04.032
本文引用格式:杨米扬, 戚婉, 石荣. MRI在克罗恩病肛瘘活动性评价与随诊中的研究进展[J]. 磁共振成像, 2023, 14(4): 181-187. DOI:10.12015/issn.1674-8034.2023.04.032.

0 前言

       克罗恩病(Crohn's disease, CD)是一种病因和发病机制尚不明确的慢性非特异性炎症性疾病,近年来在我国发病率显著增加[1]。CD属于炎症性肠病(inflammatory bowel disease, IBD)范畴,以透壁性炎症为主要特点,可以破坏肛管和黏膜的完整性,从而导致瘘管和脓肿等并发症的发生[2]。CD肛瘘(perianal fistulizing CD, pfCD)是CD最常见的并发症,临床通常以腹泻、腹痛、黏液、肠道狭窄、体质量减轻为主要特征[3]。pfCD患者约占CD患者的40%,发作频率与CD病情发展程度呈正相关[4, 5, 6, 7]。pfCD医治难、发病率高、患者会出现疼痛、流脓等表现,严重者会出现大便失禁等症状,不仅降低患者的生活质量,也给社会经济和医疗带来了沉重的负担[8]。目前临床根据疾病活动度将抗生素、生物制剂、免疫抑制剂等药物结合手术作为主要的治疗手段[9]。其中,抗肿瘤坏死因子(TNF-α)单克隆抗体(如英夫利昔单抗、阿达木单抗、赛妥珠单抗等)的出现为手术提供了更多选择,与其他细胞药物、免疫调节剂与抗生素一起共同改善了患者的预后结局[10, 11, 12]

       盆底解剖结构错综复杂,过去对盆腔各疾病进行精确诊断一直都是难题。近二十年来,随着影像技术的不断发展,盆腔MRI具有软组织分辨率高、重复性强、无创、无辐射、多参数任意角度成像等优势,不仅可以细致观察盆底解剖结构,还能联合功能成像共同反映盆底功能状态,在盆底疾病的早期诊断、治疗、降低治疗失败率和复发率等方面起着至关重要的作用[13]。目前出现了许多基于盆腔MRI的影像学评价指标与新技术,这也为pfCD的精确诊断提供了理论与实践依据。因此,对pfCD的MRI研究进展进行整理和归纳具有重要意义。本文将从盆腔MRI的诊断价值、鉴别诊断、活动度评价、随访评价和新技术五个方面进行归纳总结,以期为患者的精准治疗提供充分的信息。

1 盆腔MRI在pfCD的诊断价值

       盆腔MRI具有非侵入性的特点、可以将内口、外口、瘘管、脓肿的位置及其与肛门括约肌之间的关系清晰地显示出来,为pfCD的术前评估提供了准确的参考依据,在诊断及药物治疗期间评估瘘管愈合方面展现出独有的优势[14, 15]

       大量研究表明,pfCD患者在停止治疗后瘘管可能会重新开放,盆腔MRI相较于其他影像学检查在评价瘘管愈合方面具有显著的优势[16, 17, 18, 19]。复杂性肛瘘患者和pfCD患者术前行盆腔MRI检查对手术的指导规划作用比单纯性肛瘘患者和非pfCD患者效果更好[20]。SIDDIQUI等[21]对过去文献总结发现,虽然盆腔MRI和腔内超声(endoanal ultrasound, EUS)诊断pfCD的敏感度均为87%,但是盆腔MRI诊断特异度(69%)要显著高于EUS(43%)。WISE等[22]比较了盆腔MRI与EUS在pfCD的术前评估发现,盆腔MRI对脓肿的检测和瘘管分类都优于EUS并呈现出逐步取代其他影像学检查的趋势。美国结直肠外科医师学会(American Society of Colon & Rectal Surgeons, ASCRS)于2011年11月制订的《肛周脓肿和肛瘘治疗指南》中将影像辅助检查技术如瘘管造影、EUS、CT和MRI推荐等级定为1C[23]。随着影像技术的不断完善与发展,其在2016年发表的《肛周脓肿、肛瘘和直肠阴道瘘治疗指南》中将这一推荐等级提高到1B[24]。2019年欧洲克罗恩病和结肠炎组织(European Crohn's and Colitis Organization, ECCO)和欧洲胃肠和腹部放射学会(European Society of Gastrointestinal and Abdominal Radiology, ESGAR)在IBD诊断与评估指南中指出MRI是诊断和分类肛周CD最准确的影像学方法[25]。同年我国pfCD共识专家组也提出对有症状和体征的pfCD应常规进行盆腔MRI检查,可结合麻醉下探查(examination under anaesthesia, EUA)和EUS,以提高pfCD诊断的准确性[1]。目前,盆腔MRI作为pfCD影像检查的金标准,已广泛应用于瘘管分型、术中规划以及pfCD患者的随访中[26, 27, 28, 29, 30]

2 盆腔MRI在pfCD的鉴别作用

       临床中一些普通肛瘘因处于活动性、周围伴发脓肿等特点,在影像诊断中往往需要与pfCD相鉴别。2019年《克罗恩病肛瘘诊断与治疗的专家共识意见》[1]指出,普通肛瘘主要指肛隐窝腺源性、非特异性感染性肛瘘。为了鉴别pfCD与普通肛瘘,解剖学分类标准常采用Parks分型[31]及St.James分级[32]。pfCD与普通肛瘘的比较详见表1

       CHIN等[33]对既往pfCD研究总结发现,pfCD的瘘管分支数、内口数及脓肿数较普通肛瘘明显增多,直肠炎、肛管炎的发病率明显提高。pfCD较普通肛瘘具有以下影像学特征:马蹄形瘘管,直肠/肛管、直肠/阴道、直肠/阴囊等复杂瘘,更容易发生盆腔积液、活动性直肠炎、肛周蜂窝织炎和腹股沟、直肠周围淋巴结肿大[33]。活动性直肠炎是减少pfCD瘘管愈合和增加复发的重要因素[34]。目前,直肠壁厚度、直肠系膜淋巴结大小、直肠壁内脂肪和爬行脂肪(creeping fat, CrF)被认为与盆腔MRI诊断直肠炎息息相关。其中,肠壁增厚已被证实是与pfCD严重程度高度相关的影像学表现[35]。因此,活动性直肠炎的诊断在鉴别pfCD与非pfCD中发挥着举足轻重的作用。

       活动性直肠炎肠壁因CD活动期而水肿增厚,影像学表现通常为:肠壁增厚、T1WI呈低信号、T2WI呈高信号、T2WI脂肪抑制(T2WI fat suppression, T2WI-FS)序列肠壁仍呈明显高信号、扩散加权成像(diffusion-weighted imaging, DWI)可见高信号;增强可见明显强化,周围血管增多、增粗、紊乱,周围淋巴结肿大,增强部分可见肛提肌上间隙、坐骨直肠间隙或高位括约肌间隙等脓肿聚集;部分肠壁急性期增强可见分层强化,即病变肠壁中央因黏膜下组织水肿呈低信号,处于急性期的黏膜和浆膜层呈高信号,又称“靶征”,慢性期肠壁呈均匀一致的单层强化;部分患者可出现邻近脏器侵犯情况,如直肠阴道瘘、直肠尿道瘘等。多项文献指出[36, 37],肠壁T2WI-FS信号强度明显高于周围正常肠壁可以作为CD活动的预测因子。故而可以通过直肠壁增厚,肠壁T2WI-FS高信号特征来鉴别pfCD和非克罗恩肛瘘。

       化脓性汗腺炎(hidradenitis suppurativa, HS)是一种因毛囊上皮异常破溃而继发局部脓肿的一种慢性、炎症性皮肤病,病变好发于腋窝、乳房下区、肛周等毛囊皮脂腺、顶泌汗腺丰富的部位[38]。多项研究表明[39, 40],与一般人群相比,HS在IBD人群中患病率更高,且在IBD人群中HS合并CD的发病率高达38%。HS在进展过程中当累及肛门括约肌时,会出现类似pfCD的影像学症状,因此需要对肛周HS与pfCD进行鉴别。影像学上通常建议采用MRI对深部肛周HS与pfCD相鉴别[41]。肛周HS与pfCD的比较详见表2

       MONNIER等[42]对23例HS与46例CD患者进行MRI随访发现,相较于pfCD,肛周HS多表现为双侧对称式无分支窦道、直肠壁无增厚、HS主要病变不集中于肛周区域等影像学特点(特异度96%)。其中窦道定义为因化脓性病灶导致的异常皮下腔隙,通常不与皮肤相通。尽管pfCD与肛周HS在MRI影像学表现相互重叠,但肛周窦道双侧对称、肛周区域非病变显著区、无直肠壁增厚这三个特征结合HS的特异性诊断可以对二者进行准确的鉴别[41, 42]

表1  克罗恩病肛瘘与普通肛瘘特点比较
Tab. 1  Comparison of perianal fistulizing Crohn's disease and common perianal fistula
表2  克罗恩病肛瘘与肛周化脓性汗腺炎特点比较
Tab. 2  Comparison of perianal fistulizing Crohn's disease and perianal hidradenitis suppurativa

3 盆腔MRI在评估pfCD活动度的作用

       目前常见的评价pfCD活动性指标有:瘘管引流(fistula drainage assessment, FDA)、肛周疾病活动指数(perianal disease activity index, PDAI)和儿童CD活动指数。对pfCD活动性的评估主要基于临床与影像学两个方面。临床评估有效,但没有比较客观的定量评价标准;影像学评估客观真实,但是成本较大且没有广泛接受的评估体系[20]。随着影像技术的不断发展,MRI作为pfCD诊断的金标准,在pfCD活动度的影像学评估中发挥着越来越重要的作用。临床上常采用PDAI来评价pfCD的活动度。PDAI包括日常活动时疼痛或受限程度、性生活受限程度、瘘管排液、肛瘘类型、肛周硬结情况5个评价项目,总分在0~25分之间,当PDAI>4分则认为瘘管具有活动性[43]。有学者表示,在实际临床中需要将PDAI与影像学评估相结合作为pfCD更加精确的评价标准[44]

       影像学常采用Van Assche评分[27](Van Assche index, VAI)来评价pfCD的活动度。VAI包括6个评价项目:瘘管的数目、位置、范围、T2WI信号强度、是否合并支腔、直肠(肛管)壁情况,总分在0~22分之间(表3)。虽然VAI在pfCD的活动度评价方面提供了一个较为完善的影像学评价指标。然而,VAI本身存在各项目缺乏标准化评分规则、没有在增强序列上对瘘管进行评价、不能有效评估瘘管活动度等问题[45],其准确度仍有待商榷。

       SAMAAN等[28]用100 mm视觉模拟评分对瘘管活动性和复杂程度进行评分。在原有的VAI基础上增加了增强T2WI高信号评分、主要瘘管特征评分和脓肿评分,丰富了范围评分标准和直肠壁情况评分标准,生成了改良VAI评分(modified-Van Assche index, m-VAI),详见表3。相较于VAI,m-VAI对原有评价项目和新纳入的评价项目制订了统一的定义和评分标准,大大提高了评分的准确性。然而,VAN RIJN等[46]对30例接受TNF-α治疗的pfCD患者进行m-VAI和VAI评估发现,虽然大部TNF-α治疗临床应答患者的m-VAI评分明显下降,但是仍有三分之一的应答者评分没有下降。这表明临床上仍需要对m-VAI进行进一步优化以提高其对pfCD随访评价的准确性。

       HINDRYCKX等[29]对原有的VAI和m-VAI评分进行评估并开发了一种新的评分,即MAGNIFI-CD评分。MAGNIFI-CD评分包括瘘管数目、长度、范围、炎性肿块状况、T2WI及增强下信号强度、主要瘘管特征6个评价项目,总分在0~25分之间(表3)。与VAI相比,该评分补充了多项肛周炎症相关指标(增强序列信号强度、瘘管长度、炎性肿块、瘘管特征),大大提高了评价的可靠性;与m-VAI相比,当分支瘘管较多时,MAGNIFI-CD主要对状况最差的瘘管进行评估,具有更好的临床操作性。HINDRYCKX等[29]发现VAI和m-VAI评分中直肠壁的评价与疾病的严重程度无直接关系。VAN RIJN等[47]发现,术后MRI可见瘘管壁纤维化和MAGNIFI-CD评分可准确预测pfCD远期愈合情况,对pfCD的随访有一定价值。其中MRI显示瘘管壁纤维化的征象可作为远期愈合的有力指标。因此,相较于VAI和m-VAI,MAGNIFI-CD可能是一种更有效的pfCD影像学活动度评价指标。

       CHOSHEN等[30]基于小儿盆腔MRI开发了一种新评分,即PEMPAC评分。该评分是首个针对儿童pfCD活动性的盆腔MRI评价指标。通过比较儿童人群中PEMPAC和VAI、m-VAI、MAGNIFI-CD各评价项目发现,PEMPAC评分与VAI具有高度的相关性(r=0.92,P<0.001),首次在儿童人群验证了VAI的准确性。PEMPAC包括瘘管数目、T2WI信号强度、瘘管位置、瘘管长度、是否合并支腔5个评价项目,总分在0~41分之间(缓解4~10分;活动≥10分;严重≥30分),详见表3。然而,国内外暂无其他学者对PEMPAC的准确性进行系统性评价,目前仍需大量高级别的循证医学证据与临床研究予以佐证。

表3  以盆腔MRI为基础的克罗恩病肛瘘活动度量化指标
Tab. 3  Pelvic MRI-based indices for quantifying perianal fistulizing Crohn's disease activity

4 盆腔MRI在pfCD治疗随访的评价

       2021年,美国胃肠协会(American Gastroenterological Association, AGA)[11]认为目前仍缺乏对现有药物与治疗措施进行利弊评估,仍需要对评价患者预后的各项指标进行改进。临床上,盆腔MRI由于可以结合临床治疗准确评价患者瘘管的活动度与愈合状况,对pfCD的长期治疗疗效随访具有重要的意义。

       盆腔MRI对于pfCD的治疗随访通常采用VAI评分。然而KARMIRIS等[48]对59例经英夫利昔单抗治疗的pfCD患者研究发现,与治疗后中短期患者相比(英夫利昔单抗治疗不超过1年),远期治疗患者(英夫利昔单抗治疗超过1年)的VAI评分并没有下降。TOUGERON等[49]发现,经英夫利昔单抗治疗的pfCD患者VAI评分仅仅在(18.5±14)个月时下降。SAMAAN等[28]认为VAI仅描述了T2WI图像特征并通过删除评分者不一致的评价来提高评分的可靠性,没有确定瘘管愈合的准确指标。综上所述,VAI可能是英夫利昔单抗治疗pfCD中短期可靠的随访指标,但在远期随访方面准确性较低。因此临床中仍需要对VAI加以改进以提高其远期随访的准确性。目前,该评分已经于近期提出修改,但尚未得到外部验证[29]

       目前,影像与临床对瘘管愈合的定义仍存较大分歧。影像学愈合定义为盆腔MRI可见瘘管内口消失、T2WI、T2WI-FS序列可见高信号瘘管影消失。然而,影像学愈合通常较临床愈合延迟12个月[50]。THOMASSIN等[51]对49例pfCD患者进行长期随访发现,26例表现为临床愈合的患者(定义为FDA评估正常)中仅有16例达到影像学愈合标准。这表明虽然影像学愈合较临床愈合具有一定的滞后性,但在准确评价pfCD患者瘘管愈合方面优于临床愈合,临床上将各项临床检查与盆腔MRI相结合可能可以改善pfCD患者的预后状况。虽然影像学可以准确评估瘘管的愈合状况,但是临床中pfCD患者停止TNF-α治疗后往往出现瘘管复发的现象。TOZER等[50]对41例pfCD或直肠阴道瘘的患者研究发现,12例接受了英夫利昔单抗的患者和3例接受了阿达木单抗的患者皆表现为影像学愈合,但有7例患者在停止治疗后出现瘘管复发。然而,该研究对影像学愈合的定义中允许病灶部位残存少量细小高信号影,故不能准确反映影像学愈合指标对pfCD预后的评价作用。目前关于影像学愈合对pfCD患者的远期预后评估价值尚不明确,仍需要更多大样本多中心的临床研究对影像学愈合的疗效随访价值加以佐证。

5 基于MRI的新技术在pfCD中的应用

       随着MRI新技术的不断发展,诸如DWI、动态对比增强MRI(dynamic contrast-enhanced MRI, DCE-MRI)、磁化转移(magnetization transfer, MT)成像和T2定量成像(T2 mapping)等技术的出现为pfCD的MRI诊治提供了更多生物学信息,在患者预后、并发症评估方面发挥了举足轻重的作用。

       DWI是一种对组织内液体水分子随机运动敏感的MRI技术。水分子扩散阻抗受组织细胞化程度和完整细胞膜的影响,可以用表观扩散系数(apparent diffusion coefficient, ADC)值来定量评估[52]。有学者对55例pfCD患者研究发现,活动性pfCD患者ADC平均值明显低于非活动性pfCD患者[53]。活动性肛瘘由于瘘管炎症,局部水分子扩散受限,DWI通常表现为高敏感因子(高b值)。相反,非活动性肛瘘由于管壁纤维化,b值较活动性肛瘘明显降低[54]。多项研究表明,与常规T2WI相比,T2WI联合DWI可以显著提高瘘管的诊断率、有助于对瘘管周围的炎性肿块和脓肿加以鉴别[55, 56, 57]。综上,DWI在pfCD的诊断与鉴别诊断中发挥着重要的作用,DWI联合多种动态MRI对pfCD诊断可能会成为未来发展的趋势。

       DCE-MRI是一种注射钆对比剂的动态MRI灌注技术,其通过量化感兴趣区钆对比剂的吸收程度来定量评估组织血管的血流状况[58]。GRASSI等[59]通过测量对比剂从血浆到血管外细胞外空间的容积转运常数(volume transport constant, Ktrans)和对比剂从血管外细胞外空间回流到血浆的速率常数(rate constant, Kep)发现,活动性肠段、pfCD的Ktrans与Kep值较非活动性肠段、普通肛瘘的Ktrans与Kep值显著升高,此现象可能与C反应蛋白相关[60]。ZIECH等[61]首次使用DCE-MRI评估pfCD患者的预后发现,手术应答患者的Ktrans指数在TNF-α治疗后第六周开始显著下降,证明了DCE-MRI与PDAI的相关性。ALYAMI等[36]对各项定量MRI序列研究发现,DCE-MRI可以定量量化组织微血管的功能,在评估pfCD的活动性方面具有很大潜力。LEFRANÇOIS等[62]回顾性分析了43例结合了DCE-MRI的体素内不相干运动(intravoxel incoherent motion diffusion-weighted imaging, IVIM)-DWI检查的肛瘘患者发现,与单独IVIM-DWI序列相比,加入了DCE-MRI的IVIM-DWI序列在区分活动性与非活动性肛瘘中具有显著优势。然而该研究目前缺乏病理学佐证,仍需要大量临床试验来确定其在活动性肛瘘和非活动性肛瘘的鉴别作用。

       MT成像是近几年出现的一种全新的MRI技术。组织中的水分子可以分为自由水(不依附蛋白质分子)和结合水(依附蛋白质分子),在MT成像中先对组织施加一个预脉冲波(约1000~2000 Hz),该脉冲使得组织蛋白质分子与结合水分子中的质子被激发而产生能量,该能量会传递至周围自由水分子中,自由水分子由于能量饱和效应而在正式成像中表现为组织信号强度降低。组织蛋白数量越多,MT传递给自由水分子的能量就越多,信号强度降低越明显,测得的磁化转移率(magnetization transfer ratio, MTR)也越高[63, 64]。PINSON等[64]对29例pfCD患者研究发现,非活动期肛瘘的MTR明显低于活动期肛瘘。其原因可能为活动性瘘管的炎性肉芽组织内蛋白质含量较高,随着pfCD患者治疗后炎症不断消退,瘘管内炎性肉芽组织减少而导致MTR降低。然而,该研究没有对各患者施加相同的预脉冲波,可能会对测量的MTR产生影响。此外,该研究并没有对治疗效果进行MTR评估。因此,目前仍需要更多的临床试验来评估MT在活动性与非活动性肛瘘的诊断作用以及对pfCD的疗效随访作用。

       ALYAMI等[36]认为虽然T2 mapping技术尚未应用于pfCD临床疗效评估,但基于T2WI-FS对液体和炎症的高敏感,T2 mapping结合临床症状有望作为预测pfCD患者预后的测量工具。目前,该技术已经广泛地应用于心肌水肿的诊断之中[65]

       另一个全新领域是3D可视化建模下追踪瘘管的技术。ALYAMI等[36]通过MRI扫描整个瘘管进行简单体积测量,通过比较同一区域治疗前后的定量参数来对pfCD进行疗效随访。LAM等[66]利用区域生长法对3D-T2WI上的瘘管进行分割并得到了首个pfCD的3D模型。该模型通过多平面可视化瘘管解剖图像帮助临床医生了解瘘管的空间定位、瘘管与分支瘘管的走行,有助于临床医生对手术术式进行更加精确的选择。GUZ等[67]将pfCD患者的MRI图像与3D打印结合起来,通过3D打印的个体化模型使患者最大限度地参与到诊疗活动中,有助于医患之间共享决策的施行。然而,目前仍没有专门软件帮助医生观察和定义3D瘘管。3D打印虽然可以为患者提供个性化医疗服务,但是由于其存在技术难度较大、费用较高、时间周期较长、人工勾画瘘管误差以及无法用于临床监测药物疗效、评估挂线疗法的拆线时间和确定性手术时机等问题,目前在临床上开展较少。pfCD的3D建模、基于3D建模的有限元分析、人工智能及影像组学对pfCD瘘管特征的深度学习可能是未来影像学发展的趋势。然而,目前基于上述MRI新技术鉴别和评估pfCD的研究较少,仍需进一步加以深度挖掘。

6 小结

       影像学已成为评估pfCD的重要手段,其中MRI因软组织分辨率高、无创、无辐射、多参数任意角度成像等特点而广泛应用于pfCD的评估中。对pfCD进行影像学鉴别以及评估瘘管活动性对于pfCD的诊断非常重要,同时MRI可以通过VAI、m-VAI、NAGNIFI-CD、PEMPAC评分等影像学指标评估炎症活动性从而指导预后。DWI、DCE-MRI、MT、T2 mapping技术的出现使MRI在诊断和评估pfCD预后中发挥更大的作用。基于MRI的3D可视化建模为MRI在pfCD的诊断和治疗随访提供了更多的思路。但目前这几种新技术都处于起步阶段,其技术问题以及是否能为临床带来更大的帮助等仍需要通过大量临床研究加以佐证。

[1]
克罗恩病肛瘘共识专家组. 克罗恩病肛瘘诊断与治疗的专家共识意见[J]. 中华炎性肠病杂志, 2019, 3(2): 105-110. DOI: 10.3760/cma.j.issn.2096-367X.2019.02.001.
Experts group of consensus on perianal fistulizing Crohn's disease. Experts consensus on the diagnosis and treatment of perianal fistulizing Crohn's disease[J]. Chin J Inflamm Bowel Dis, 2019, 3(2): 105-110. DOI: 10.3760/cma.j.issn.2096-367X.2019.02.001.
[2]
PANES J, REINISCH W, RUPNIEWSKA E, et al. Burden and outcomes for complex perianal fistulas in Crohn's disease: systematic review[J]. World J Gastroenterol, 2018, 24(42): 4821-4834. DOI: 10.3748/wjg.v24.i42.4821.
[3]
凡奎, 熊倩, 吴昊欣, 等. 间充质干细胞及其治疗克罗恩病肛瘘的研究进展[J]. 中国肛肠病杂志, 2022, 42(8): 78-80. DOI: 10.3969/j.issn.1000-1174.2022.08.029.
FAN K, XIONG Q, WU H X, et al. Research progress of mesenchymal stem cells and their treatment of Crohn's disease anal fistula[J]. Chin J Coloproctology, 2022, 42(8): 78-80. DOI: 10.3969/j.issn.1000-1174.2022.08.029.
[4]
SCHWARTZ D A, PEMBERTON J H, SANDBORN W J. Diagnosis and treatment of perianal fistulas in Crohn disease[J]. Ann Intern Med, 2001, 135(10): 906-918. DOI: 10.7326/0003-4819-135-10-200111200-00011.
[5]
SCHWARTZ D A, LOFTUS E V, TREMAINE W J, et al. The natural history of fistulizing Crohn's disease in Olmsted County, Minnesota[J]. Gastroenterology, 2002, 122(4): 875-880. DOI: 10.1053/gast.2002.32362.
[6]
LAPIDUS A, BERNELL O, HELLERS G, et al. Clinical course of colorectal Crohn's disease: a 35-year follow-up study of 507 patients[J]. Gastroenterology, 1998, 114(6): 1151-1160. DOI: 10.1016/s0016-5085(98)70420-2.
[7]
SICA G S, DI CARLO S, TEMA G, et al. Treatment of peri-anal fistula in Crohn's disease[J]. World J Gastroenterol, 2014, 20(37): 13205-13210. DOI: 10.3748/wjg.v20.i37.13205.
[8]
XU F, LIU Y, WHEATON A G, et al. Trends and factors associated with hospitalization costs for inflammatory bowel disease in the United States[J]. Appl Health Econ Health Policy, 2019, 17(1): 77-91. DOI: 10.1007/s40258-018-0432-4.
[9]
陶冉, 黄晓琳, 龚恬韵, 等. 克罗恩病肛瘘中医药治疗研究进展[J]. 陕西中医, 2022, 43(5): 666-669. DOI: 10.3969/j.issn.1000-7369.2022.05.029.
TAO R, HUANG X L, GONG T Y, et al. Research progress of traditional Chinese medicine in the treatment of anal fistula in Crohn's disease[J]. Shaanxi J Tradit Chin Med, 2022, 43(5): 666-669. DOI: 10.3969/j.issn.1000-7369.2022.05.029.
[10]
FEUERSTEIN J D, HO E Y, SHMIDT E, et al. AGA clinical practice guidelines on the medical management of moderate to severe luminal and perianal fistulizing Crohn's disease[J]. Gastroenterology, 2021, 160(7): 2496-2508. DOI: 10.1053/j.gastro.2021.04.022.
[11]
SINGH S, PROCTOR D, SCOTT F I, et al. AGA technical review on the medical management of moderate to severe luminal and perianal fistulizing Crohn's disease[J/OL]. Gastroenterology, 2021, 160(7): 2512-2556.e9 [2022-11-21]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8986997/. DOI: 10.1053/j.gastro.2021.04.023.
[12]
中华医学会消化病学分会炎症性肠病学组儿科协作组. 抗肿瘤坏死因子-α单克隆抗体治疗儿童克罗恩病的专家共识[J]. 中华炎性肠病杂志, 2021(2): 114-124. DOI: 10.3760/cma.j.cn101480-20210105-00001.
Inflammatory Bowel Disease Group-Pediatric Group of Chinese Society of Gastroenterology of Chinese Medical Association. Chinese expert consensus on anti-tumor necrosis factor-αmonoclonal in pediatric Crohn′s disease[J]. Chin J Inflamm Bowel Dis, 2021(2): 114-124. DOI: 10.3760/cma.j.cn101480-20210105-00001.
[13]
GREER M C, CYTTER-KUINT R, PRATT L T, et al. Clinical-stage approaches for imaging chronic inflammation and fibrosis in Crohn's disease[J]. Inflamm Bowel Dis, 2020, 26(10): 1509-1523. DOI: 10.1093/ibd/izaa218.
[14]
HADDOW J B, MUSBAHI O, MACDONALD T T, et al. Comparison of cytokine and phosphoprotein profiles in idiopathic and Crohn′s disease-related perianal fistula[J]. World J Gastrointest Pathophysiol, 2019, 10(4): 42-53. DOI: 10.4291/wjgp.v10.i4.42.
[15]
倪耿欢, 赵宏伟, 亓昌珍, 等. 克罗恩病肛瘘与非克罗恩病肛瘘的MRI特征对比分析[J]. 中华放射学杂志, 2019, 53(4): 305-309. DOI: 10.3760/cma.j.issn.1005?1201.2019.04.012.
NI G H, ZHAO H W, QI C Z, et al. Comparative analysis of MR imaging findings of perianal fistulas in patients with and without Crohn disease[J]. Chin J Radiol, 2019, 53(4): 305-309. DOI: 10.3760/cma.j.issn.1005?1201.2019.04.012.
[16]
SAVOYE-COLLET C, SAVOYE G, KONING E, et al. Fistulizing perianal Crohn′s disease: contrast-enhanced magnetic resonance imaging assessment at 1 year on maintenance anti-TNF-alpha therapy[J]. Inflamm Bowel Dis, 2011, 17(8): 1751-1758. DOI: 10.1002/ibd.21568.
[17]
NG S C, PLAMONDON S, GUPTA A, et al. Prospective evaluation of anti-tumor necrosis factor therapy guided by magnetic resonance imaging for Crohn's perineal fistulas[J]. Am J Gastroenterol, 2009, 104(12): 2973-2986. DOI: 10.1038/ajg.2009.509.
[18]
SPRADLIN N M, WISE P E, HERLINE A J, et al. A randomized prospective trial of endoscopic ultrasound to guide combination medical and surgical treatment for Crohn's perianal fistulas[J]. Am J Gastroenterol, 2008, 103(10): 2527-2535. DOI: 10.1111/j.1572-0241.2008.02063.x.
[19]
GUIDI L, RATTO C, SEMERARO S, et al. Combined therapy with infliximab and Seton drainage for perianal fistulizing Crohn's disease with anal endosonographic monitoring: a single-centre experience[J]. Tech Coloproctol, 2008, 12(2): 111-117. DOI: 10.1007/s10151-008-0411-0.
[20]
周杰, 郭敏翊, 周智洋. 磁共振成像在瘘管型肛周克罗恩病中的应用与进展[J]. 中华炎性肠病杂志(中英文), 2019, 3(4): 316-320. DOI: 10.3760/cma.j.issn.2096-367X.2019.04.009.
ZHOU J, GUO M Y, ZHOU Z Y. Applications and progress of magnetic resonance imaging in fistulizing perianal Crohn′s disease[J]. Chin J Inflamm Bowel Dis, 2019, 3(4): 316-320. DOI: 10.3760/cma.j.issn.2096-367X.2019.04.009.
[21]
SIDDIQUI M R, ASHRAFIAN H, TOZER P, et al. A diagnostic accuracy meta-analysis of endoanal ultrasound and MRI for perianal fistula assessment[J]. Dis Colon Rectum, 2012, 55(5): 576-585. DOI: 10.1097/DCR.0b013e318249d26c.
[22]
WISE P E, SCHWARTZ D A. The evaluation and treatment of Crohn perianal fistulae: EUA, EUS, MRI, and other imaging modalities[J]. Gastroenterol Clin North Am, 2012, 41(2): 379-391. DOI: 10.1016/j.gtc.2012.01.009.
[23]
WHITEFORD M H, KILKENNY J, HYMAN N, et al. Practice parameters for the treatment of perianal abscess and fistula-in-ano (revised)[J]. Dis Colon Rectum, 2005, 48(7): 1337-1342. DOI: 10.1007/s10350-005-0055-3.
[24]
VOGEL J D, JOHNSON E K, MORRIS A M, et al. Clinical practice guideline for the management of anorectal abscess, fistula-in-ano, and rectovaginal fistula[J]. Dis Colon Rectum, 2016, 59(12): 1117-1133. DOI: 10.1097/DCR.0000000000000733.
[25]
MAASER C, STURM A, VAVRICKA S R, et al. ECCO-ESGAR Guideline for Diagnostic Assessment in IBD Part 1: initial diagnosis, monitoring of known IBD, detection of complications[J]. J Crohns Colitis, 2019, 13(2): 144-164. DOI: 10.1093/ecco-jcc/jjy113.
[26]
HAGGETT P J, MOORE N R, SHEARMAN J D, et al. Pelvic and perineal complications of Crohn's disease: assessment using magnetic resonance imaging[J]. Gut, 1995, 36(3): 407-410. DOI: 10.1136/gut.36.3.407.
[27]
VAN ASSCHE G, VANBECKEVOORT D, BIELEN D, et al. Magnetic resonance imaging of the effects of infliximab on perianal fistulizing Crohn′s disease[J]. Am J Gastroenterol, 2003, 98(2): 332-339. DOI: 10.1111/j.1572-0241.2003.07241.x.
[28]
SAMAAN M A, PUYLAERT C A J, LEVESQUE B G, et al. The development of a magnetic resonance imaging index for fistulising crohn′s disease[J]. Aliment Pharmacol Ther, 2017, 46(5): 516-528. DOI: 10.1111/apt.14190.
[29]
HINDRYCKX P, JAIRATH V, ZOU G Y, et al. Development and validation of a magnetic resonance index for assessing fistulas in patients with crohn′s disease[J/OL]. Gastroenterology, 2019, 157(5): 1233-1244.e5 [2022-11-21]. https://linkinghub.elsevier.com/retrieve/pii/S0016-5085(19)41120-7. DOI: 10.1053/j.gastro.2019.07.027.
[30]
CHOSHEN S, TURNER D, PRATT L T, et al. Development and validation of a pediatric MRI-based perianal crohn disease (PEMPAC) index-a report from the ImageKids study[J]. Inflamm Bowel Dis, 2022, 28(5): 700-709. DOI: 10.1093/ibd/izab147.
[31]
PARKS A G, GORDON P H, HARDCASTLE J D. A classification of fistula-in-ano[J]. Br J Surg, 2023, 63(1): 1-12. DOI: 10.1002/bjs.1800630102.
[32]
MORRIS J, SPENCER J A, AMBROSE N S. MR imaging classification of perianal fistulas and its implications for patient management[J]. Radiographics, 2000, 20(3): 623-635. DOI: 10.1148/radiographics.20.3.g00mc15623.
[33]
CHIN KOON SIW K, ENGEL J, VISVA S, et al. Strategies to distinguish perianal fistulas related to Crohn's disease from cryptoglandular disease: systematic review with meta-analysis[J]. Inflamm Bowel Dis, 2022, 28(9): 1363-1374. DOI: 10.1093/ibd/izab286.
[34]
TRUONG A, ZAGHIYAN K, FLESHNER P. Anorectal Crohn's disease[J]. Surg Clin North Am, 2019, 99(6): 1151-1162. DOI: 10.1016/j.suc.2019.08.012.
[35]
PANÉS J, RIMOLA J. Perianal fistulizing Crohn's disease: pathogenesis, diagnosis and therapy[J]. Nat Rev Gastroenterol Hepatol, 2017, 14(11): 652-664. DOI: 10.1038/nrgastro.2017.104.
[36]
ALYAMI A, HOAD C L, TENCH C, et al. Quantitative magnetic resonance imaging in perianal Crohn's disease at 1.5 and 3.0 T: a feasibility study[J/OL]. Diagnostics (Basel), 2021, 11(11): 2135 [2022-11-21]. https://www.ncbi.nlm.nih.gov/pmc/articles/pmid/34829482/. DOI: 10.3390/diagnostics11112135.
[37]
BOUHNIK Y, LE BERRE C, ZAPPA M, et al. Development of a new index to assess small bowel inflammation severity in crohn′s disease using magnetic resonance enterography[J/OL]. Crohns Colitis 360, 2022, 4(1): otac004 [2023-03-12]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9802414/. DOI: 10.1093/crocol/otac004.
[38]
DECKERS I E, BENHADOU F, KOLDIJK M J, et al. Inflammatory bowel disease is associated with hidradenitis suppurativa: results from a multicenter cross-sectional study[J]. J Am Acad Dermatol, 2017, 76(1): 49-53. DOI: 10.1016/j.jaad.2016.08.031.
[39]
YADAV S, SINGH S, EDAKKANAMBETH VARAYIL J, et al. Hidradenitis suppurativa in patients with inflammatory bowel disease: a population-based cohort study in Olmsted County, Minnesota[J]. Clin Gastroenterol Hepatol, 2016, 14(1): 65-70. DOI: 10.1016/j.cgh.2015.04.173.
[40]
VAN DER ZEE H H, VAN DER WOUDE C J, FLORENCIA E F, et al. Hidradenitis suppurativa and inflammatory bowel disease: are they associated? Results of a pilot study[J]. Br J Dermatol, 2010, 162(1): 195-197. DOI: 10.1111/j.1365-2133.2009.09430.x.
[41]
SRISAJJAKUL S, PRAPAISILP P, BANGCHOKDEE S. Magnetic resonance imaging of hidradenitis suppurativa: a focus on the anoperineal location[J]. Korean J Radiol, 2022, 23(8): 785-793. DOI: 10.3348/kjr.2022.0215.
[42]
MONNIER L, DOHAN A, AMARA N, et al. Anoperineal disease in Hidradenitis Suppurativa: MR imaging distinction from perianal Crohn's disease[J]. Eur Radiol, 2017, 27(10): 4100-4109. DOI: 10.1007/s00330-017-4776-1.
[43]
IRVINE E J. Usual therapy improves perianal Crohn's disease as measured by a new disease activity index. McMaster IBD Study Group[J]. J Clin Gastroenterol, 1995, 20(1): 27-32.
[44]
叶孙送, 刘琼琼, 潘一滨. 克罗恩病肛瘘(肛周脓肿)MRI影像分析[J]. 浙江临床医学, 2022, 24(1): 105-106. DOI: 10.3760/cma.j.issn.0578-1426.2012.10.024.
YE S S, LIU Q Q, PAN Y B. MRI image analysis of Crohn's disease anal fistula (perianal abscess)[J]. Zhejiang Clin Med J, 2022, 24(1): 105-106. DOI: 10.3760/cma.j.issn.0578-1426.2012.10.024.
[45]
CHAMBAZ M, VERDALLE-CAZES M, DESPREZ C, et al. Deep remission on magnetic resonance imaging impacts outcomes of perianal fistulizing Crohn's disease[J]. Dig Liver Dis, 2019, 51(3): 358-363. DOI: 10.1016/j.dld.2018.12.010.
[46]
VAN RIJN K L, LANSDORP C A, TIELBEEK J A W, et al. Evaluation of the modified Van Assche index for assessing response to anti-TNF therapy with MRI in perianal fistulizing Crohn's disease[J]. Clin Imaging, 2020, 59(2): 179-187. DOI: 10.1016/j.clinimag.2019.10.007.
[47]
VAN RIJN K L, MEIMA-VAN PRAAG E M, BOSSUYT P M, et al. Fibrosis and MAGNIFI-CD activity index at magnetic resonance imaging to predict treatment outcome in perianal fistulizing Crohn's disease patients[J]. J Crohns Colitis, 2022, 16(5): 708-716. DOI: 10.1093/ecco-jcc/jjab168.
[48]
KARMIRIS K, BIELEN D, VANBECKEVOORT D, et al. Long-term monitoring of infliximab therapy for perianal fistulizing Crohn's disease by using magnetic resonance imaging[J]. Clin Gastroenterol Hepatol, 2011, 9(2): 130-136. DOI: 10.1016/j.cgh.2010.10.022.
[49]
TOUGERON D, SAVOYE G, SAVOYE-COLLET C, et al. Predicting factors of fistula healing and clinical remission after infliximab-based combined therapy for perianal fistulizing Crohn's disease[J]. Dig Dis Sci, 2009, 54(8): 1746-1752. DOI: 10.1007/s10620-008-0545-y.
[50]
TOZER P, NG S C, SIDDIQUI M R, et al. Long-term MRI-guided combined anti-TNF-α and thiopurine therapy for Crohn's perianal fistulas[J]. Inflamm Bowel Dis, 2012, 18(10): 1825-1834. DOI: 10.1002/ibd.21940.
[51]
THOMASSIN L, ARMENGOL-DEBEIR L, CHARPENTIER C, et al. Magnetic resonance imaging may predict deep remission in patients with perianal fistulizing Crohn's disease[J]. World J Gastroenterol, 2017, 23(23): 4285-4292. DOI: 10.3748/wjg.v23.i23.4285.
[52]
HAGMANN P, JONASSON L, MAEDER P, et al. Understanding diffusion MR imaging techniques: from scalar diffusion-weighted imaging to diffusion tensor imaging and beyond[J]. Radiographics, 2006, 26(Suppl 1): S205-S223. DOI: 10.1148/rg.26si065510.
[53]
王绍娟, 唐晓雯, 王中秋, 等. 磁共振弥散加权成像在评估Crohn's肛瘘炎症活动度中的价值[J]. 中南大学学报(医学版), 2019, 44(2): 173-179. DOI: 10.11817/j.issn.1672-7347.2019.02.009.
WANG S J, TANG X W, WANG Z Q, et al. Value of magnetic resonance diffusion-weighted imaging for evaluating the inflammatory activity of perianal Crohn's fistula[J]. J Central South Univ Med Sci, 2019, 44(2): 173-179. DOI: 10.11817/j.issn.1672-7347.2019.02.009.
[54]
BORUAH D K, HAZARIKA K, AHMED H, et al. Role of diffusion-weighted imaging in the evaluation of perianal fistulae[J]. Indian J Radiol Imaging, 2021, 31(1): 91-101. DOI: 10.1055/s-0041-1729673.
[55]
CAVUSOGLU M, DURAN S, SÖZMEN CILIZ D, et al. Added value of diffusion-weighted magnetic resonance imaging for the diagnosis of perianal fistula[J]. Diagn Interv Imaging, 2017, 98(5): 401-408. DOI: 10.1016/j.diii.2016.11.002.
[56]
CATTAPAN K, CHULROEK T, KORDBACHEH H, et al. Contrast- vs. non-contrast enhanced MR data sets for characterization of perianal fistulas[J]. Abdom Radiol (NY), 2019, 44(2): 446-455. DOI: 10.1007/s00261-018-1761-3.
[57]
BAIK J, KIM S H, LEE Y, et al. Comparison of T2-weighted imaging, diffusion-weighted imaging and contrast-enhanced T1-weighted MR imaging for evaluating perianal fistulas[J]. Clin Imaging, 2017, 44: 16-21. DOI: 10.1016/j.clinimag.2017.03.019.
[58]
LEE S, CHOI Y H, CHO Y J, et al. Quantitative evaluation of Crohn's disease using dynamic contrast-enhanced MRI in children and young adults[J]. Eur Radiol, 2020, 30(6): 3168-3177. DOI: 10.1007/s00330-020-06684-1.
[59]
GRASSI G, LAINO M E, FANTINI M C, et al. Advanced imaging and Crohn's disease: an overview of clinical application and the added value of artificial intelligence[J/OL]. Eur J Radiol, 2022, 157: 110551 [2022-11-21]. https://www.sciencedirect.com/science/article/abs/pii/S0720048X22004016?via%3Dihub. DOI: 10.1016/j.ejrad.2022.110551.
[60]
ZHU J G, ZHANG F M, ZHOU J F, et al. Assessment of therapeutic response in Crohn's disease using quantitative dynamic contrast enhanced MRI (DCE-MRI) parameters: a preliminary study[J/OL]. Medicine (Baltimore), 2017, 96(32): e7759 [2022-11-21]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5556235/. DOI: 10.1097/MD.0000000000007759.
[61]
ZIECH M L, LAVINI C, BIPAT S, et al. Dynamic contrast-enhanced MRI in determining disease activity in perianal fistulizing Crohn disease: a pilot study[J]. AJR Am J Roentgenol, 2013, 200(2): W170-W177. DOI: 10.2214/AJR.11.8276.
[62]
LEFRANÇOIS P, ZUMMO-SOUCY M, OLIVIÉ D, et al. Diagnostic performance of intravoxel incoherent motion diffusion-weighted imaging and dynamic contrast-enhanced MRI for assessment of anal fistula activity[J/OL]. PLoS One, 2018, 13(1): e0191822 [2022-11-21]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5784995/. DOI: 10.1371/journal.pone.0191822.
[63]
梁颖茵, 黎规典, 何荣兴, 等. 定量磁共振成像在遗传性肌肉病中的应用[J]. 中国现代神经疾病杂志, 2021, 21(6): 448-453. DOI: 10.3969/j.issn.1672-6731.2021.06.004.
LIANG Y Y, LI G D, HE R X, et al. Advances in quantitative MRI of hereditary myopathies[J]. Chin J Contemp Neurol Neurosurg, 2021, 21(6): 448-453. DOI: 10.3969/j.issn.1672-6731.2021.06.004.
[64]
PINSON C, DOLORES M, CRUYPENINCK Y, et al. Magnetization transfer ratio for the assessment of perianal fistula activity in Crohn's disease[J]. Eur Radiol, 2017, 27(1): 80-87. DOI: 10.1007/s00330-016-4350-2.
[65]
FOTAKI A, VELASCO C, PRIETO C, et al. Quantitative MRI in cardiometabolic disease: from conventional cardiac and liver tissue mapping techniques to multi-parametric approaches[J]. Front Cardiovasc Med, 2022, 9: 991383 [2023-03-12]. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9899858/. DOI: 10.3389/fcvm.2022.991383.
[66]
LAM D, YONG E, D'SOUZA B, et al. Three-dimensional modeling for Crohn's fistula-in-ano: a novel, interactive approach[J]. Dis Colon Rectum, 2018, 61(5): 567-572. DOI: 10.1097/DCR.0000000000001084.
[67]
GUZ W, OŻÓG Ł, AEBISHER D, et al. The use of magnetic resonance imaging technique and 3D printing in order to develop a three-dimensional fistula model for patients with Crohn's disease: personalised medicine[J]. Prz Gastroenterol, 2021, 16(1): 83-88. DOI: 10.5114/pg.2020.101629.

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