History: A 65-year-old man presents to the emergency room (ER) with generalized abdominal pain. The patient has a history pulmonary sarcoidosis but no prior history of abdominal surgeries.
病史：65岁男性，急腹痛；有肺结节病病史，无腹部手术史。
Chest and abdominal radiographs were ordered by the ER physician. Frontal view, upright radiographs of the chest and abdomen are shown below.
急诊拍摄胸腹部平片，胸部正位片及腹部立位片如下所示。
腹平片示有无肠梗阻？（答案：无）
CT images：There was a continued concern for an intra-abdominal process. A CT scan of the abdomen and pelvis with oral contrast was performed. Multiple axial and coronal images of the abdomen and pelvis are shown below.
为进一步了解腹腔内情况，行口服造影剂腹盆部CT扫描，轴位及冠状图像如下所示。
Findings
Abdominal radiograph: There is a moderate amount of gas and stool throughout the colon with no definite evidence of adynamic ileus or obstruction.
CT of the abdomen and pelvis:
- There is displacement of the cecum anteriorly and superiorly, located near the midline.
- There is a defect in the mesentery in the right abdomen with herniation of small-bowel loops through the mesenteric defect.
- There is no evidence of obstruction at this time, although oral contrast has not yet reached the involved loops of bowel.
- There is no pneumatosis or free air.
影像表现：
腹平片：结肠内可见中等量的气体及粪便，无麻痹性肠梗阻征象。
腹盆部CT：
- 盲肠向前上移位，靠近中线处；
- 右腹部局部肠系膜缺失，小肠袢经肠系膜缺损处形成疝；
- 此时仍未出现肠梗阻，尽管口服造影剂仍然没有抵达受累肠袢；
- 腹腔内未见游离气体。
Differential diagnosis
- Internal hernia
- Small-bowel obstruction
- Intussusception
- Volvulus
鉴别诊断：
- 腹内疝
- 小肠梗阻
- 肠套叠
- 肠扭转
Diagnosis: Right abdominal internal hernia
最后诊断：右侧腹内疝
There is no evidence of obstruction at this time. However, given the patient’s pain, surgical consultation is recommended.
此时仍无梗阻征象，然后如果患者出现疼痛，仍推荐进行手术。
Key points
Internal hernia 内疝
Pathophysiology
An internal hernia is a protrusion of abdominal viscera through an opening within the confines of the peritoneal cavity.
腹内脏器自其原来的位置，经过腹腔内一个正常或异常的孔道或裂隙脱位到一个异常的腔隙者称为腹内疝。
Internal hernias are divided into three categories based on the type of hernia orifice:
- Normal foramen
- Unusual peritoneal fossa or recess in the retroperitoneum
- Abnormal opening in a mesentery or peritoneal ligament
腹内疝可分为三种（基于疝孔）：
- 正常孔道
- 腹膜后少见的腹膜隐窝
- 肠系膜或腹膜韧带的异常孔道
Abnormal opening types of internal hernias have two categories:
- Transmesenteric or fenestra type, which involves both peritoneal layers
- Intramesenteric or pouch type, which involves a single peritoneal layer
腹内疝的异常孔道有两型：
- 经肠系膜型或窗型：累及双层腹膜；
- 肠系膜内型或袋型：累及单层腹膜。
Epidemiology
The estimated lifetime risk of a spontaneous abdominal hernia is 5%. Hernia repair is the second most common abdominopelvic operation in the U.S. Internal hernias are relatively rare, comprising less than 1% of all hernias. Complicated internal hernias have high mortality rates, up to 50% in some series, especially when associated with strangulation. Paraduodenal hernias are more common in men than women by a 3:1 ratio. 75% of paraduodenal hernias occur on the left side.
流行病学
- 自发性腹内疝的患病风险为5%；
- 疝修复是美国第二常见的腹盆腔手术；
- 腹内疝相对罕见，占所有疝的比例不足1%；
- 复杂的腹内疝致死率较高，合并肠绞窄时高达50%；
- 十二指肠旁疝更多见于男性（男女比例3:1）；
- 75%的十二指肠旁疝发生在左侧。
Clinical presentation
Clinical signs and symptoms of internal hernia are nonspecific and overlap with other abdominal pathologies. Nausea, vomiting, abdominal pain, and abdominal distention are most common.
临床表现：腹内疝的临床症状无特异性，与其他腹部病变有重叠，多表现为恶心、呕吐、腹痛及腹胀。
Imaging features
CT will demonstrate the following:
- Abnormal displacement of anatomic landmarks surrounding structures and vessels around the hernia sac
- Sac-like appearance, suggesting intestinal closed loop
- Convergence, engorgement, and twisting of mesenteric vessels in the hernia orifice
影像表现：
CT：
- 疝囊周围的腹部结构及血管等解剖标志位置异常；
- 囊样表现，提示肠道环封闭；
- 疝孔处肠系膜血管聚集、充血、扭转。
Differential diagnoses
- Small-bowel obstruction
- Intussusception
- Volvulus
鉴别诊断：
- 小肠梗阻
- 肠套叠
- 肠扭转
Treatment and management
Early surgical intervention is indicated to reduce the high morbidity and mortality rates associated with internal hernia.
治疗及处理：早期手术干预可以降低腹内疝的高发病率及死亡率。