Changing clinical and roentgenographic patterns of necrotizing enterocolitis.

Necrotizing enterocolitis (NEC) occasionally deviates from the classical presentation of the disease. Small bowel dilatation and pneumatosis are frequently present prior to the actual onset of the clinical presentation. Pneumatosis intestinalis, an important diagnostic sign of NEC, is quite variable; it may be present, persist, worsen, or disappear; or at times it may not be present at all. A severe complication of necrotizing enterocolitis is perforation which in 50 percent of the cases presented without obvious free intra-abdominal air. Accumulation of fluid in the abdomen is stressed as strong evidence for perforation and a strong indication for surgery. The varying features indicate that NEC has a clinical spectrum that extends from benign to severe, and recognition of all these variations will lead to better diagnosis and to a better understanding of the disease. The clinical and roentgenologic variations make classification difficult but the variety most likely represents the combination of a great number of susceptible children and a greater recognition of the disease.     

Necrotizing enterocolitis

Summary Necrotizing enterocolitis is a serious abdominal disease in infants during the first 2 months of life. The earliest radiographic finding on frontal abdominal films is initially distension of the small bowel, secondly of the colon, and pneumatosis intestinalis. Pneumatosis intestinalis is not pathognomonic for necrotizing enterocolitis; it can occur throughout life in different abdominal diseases. It can be a serious prognostic sign for abdominal ileus, but it may also occur in non-critically ill patients. Radiographic diagnosis in childhood is achieved with a frontal film of the abdomen in the prone position, and to detect a possible perforation, a left lateral abdominal decubitus exposure is necessary. Sonography and duplex sonography are helpful in evaluating progressive changes, the clinical course and the differential diagnosis. Eingegangen am 30. Dezember 1996 Angenommen am 15. Januar 1997     

Gastrointestinal complications of cytosine-arabinoside chemotherapy: findings on plain abdominal radiographs

We analyzed the findings on plain abdominal radiographs in 24 patients who had adverse gastrointestinal reactions after chemotherapy with cytosine-arabinoside (Ara-C) for treatment of acute leukemia or non-Hodgkin lymphoma. Ara-C was given with vincristine, VP 16-213, daunorubicin, amsacrine, adriamycin, or corticosteroids in various combinations and dosages. The abnormalities noted on plain abdominal radiographs included paralytic ileus (73%), cecal distension (38%), pneumatosis intestinalis (27%), thickened loops of small bowel (19%), and pneumoperitoneum (8%). One patient had small-bowel ileus simulating an obstruction. In 23%, death was directly related to gastrointestinal complications. Bowel wall erosions, necrosis, and transmural or submucosal hemorrhage were the main findings at autopsy. This experience suggests that plain abdominal radiographs are useful in the diagnosis of gastrointestinal complications associated with chemotherapy with Ara-C.     

Abdominal ultrasonography in preterm necrotizing enterocolitis. Is it superior to plain radiography?

Purpose

To explore whether abdominal ultrasound (AUS) provide additional information over plain radiography in cases of necrotizing enterocolitis (NEC).

Methods

This study is a prospective study of 30 premature neonates with NEC in our neonatal intensive care unit between August 2010 and November 2011. Fifteen premature control neonates were also included in the study.

Results

Patients were classified into two groups: the first group with suspected NEC (stage I) (n = 14) and the second with definite NEC (stage II or III) (n = 16). In group I abdominal ultrasound (AUS) revealed intramural air (n = 9) and portal venous gas (PVG) (n = 1) while plain radiography showed only gaseous distension. In group II, intramural air (n = 10), PVG (n = 2), free fluid (n = 6) focal fluid (n = 1) and free air (n = 6) detected by AUS compared to pneumatosis intestinalis (PI) (n = 2) PVG (n = 1) and free air (n = 5) by plain radiography. Additionally bowel wall thinning was detected in 2 neonates of group I and 3 of group II.

Conclusion

Our results suggest AUS to be superior to plain radiography in early detection of complication as intestinal perforation by eliciting PVG and fluid collection and so early surgical management. Therefore this may decrease morbidity and mortality rates.     

The plain abdominal radiograph in acute gastrointestinal graft-vs.-host disease

The plain abdominal radiographs of 28 patients with acute gastrointestinal graft-vs.-host disease (GVHD) were examined to determine the plain radiographic findings associated with this disorder. These findings, in order of decreasing frequency, included air-fluid levels, bowel wall/mucosal fold thickening, gasless abdomen, bowel dilatation, pneumatosis intestinalis, and ascites. When a number of these findings are present, the plain abdominal radiographs may be sufficiently characteristic to suggest gastrointestinal GVHD. Differentiating acute gastrointestinal GVHD from small-bowel obstruction is often of major clinical importance. Fortunately, the bowel gas pattern in acute gastrointestinal GVHD rarely suggests obstruction and, thus, bowel obstruction can usually be excluded on the basis of plain radiographs alone.     

小儿肠梗阻的腹部X线平片和CT诊断价值分析

目的：分析腹部X线平片和CT对小儿肠梗阻的诊断价值，重点探讨小儿绞窄性肠梗阻的CT表现。材料和方法：收集2002年1月-2004年6月复旦大学附属儿科医院手术证实肠梗阻23例，术前24h均拍摄腹部正侧位X线平片，其中14例行腹部CT扫描。结果：23例肠梗阻术前诊断正确率：腹部X线平片为69．6％（16／23）：CT为100％（14／14）。其中，绞窄性肠梗阻术前诊断正确率：腹部X线平片为38．9％（7／18）；CT为90．9％（10／11）。11例绞窄性肠梗阻的主要CT表现包括：小肠壁增厚9例；CT平扫肠壁密度增高7例和“靶征，，2例；CT增强扫描肠壁强化低于正常者6例，3例延迟扫描强化。肠系膜血管增粗水肿5例，4、肠壁积气4例，腹水6例。结论：CT诊断小儿肠梗阻，特别是显示肠绞窄，较腹部X线平片优越。     

新生儿坏死性小肠结肠炎的早期X线表现及临床分析

目的通过对新生儿坏死性小肠结肠炎(NEC)X线的征象分析,提高对本病的早期诊断,加深对本病的进一步认识。方法收集我院2005年12月～2011年12月有完整资料经X线诊断的35例NEC患儿,对其X线征象做出总结分析。结果 35例新生儿坏死性小肠结肠炎患儿早期X线征象35例均有肠道动力性改变;肠壁积气21例;肝门静脉积气影5例;肠穿孔气腹7例。结论新生儿NEC早期X线征象为肠管动力性改变为主,而肠壁间积气、肝门静脉积气为NEC的特征性X线征象,而背景模糊,腹腔密度增高是腹腔渗液进行性增多的X线征象,提示NEC进展恶化的表现。因此NEC的早期诊断对治疗和评估有重要意义。     

Pneumatosis intestinalis in bone-marrow transplantation patients: diagnosis on routine chest radiographs

We report seven cases of pneumatosis intestinalis that was initially detected on routine chest radiographs made in adult bone-marrow transplantation patients. The cases were collected over a 13-month period. The chest radiographs generally underestimated the extent of the pneumatosis, as subsequently seen on plain abdominal films. However, the portions of bowel most extensively involved were those seen on the chest radiographs (transverse colon, hepatic and splenic flexures, stomach). One patient had pneumoperitoneum also. Pneumatosis developed within 6-293 days after transplantation. The cause of pneumatosis intestinalis was multifactorial. Three patients were asymptomatic. Clinical management of all seven patients was altered because of the detection of pneumatosis. The dose of steroids was increased in three patients to treat graft-vs-host disease, antibiotic drugs were given to three patients for enteric pathogens, and bowel rest was prescribed for one patient with mucosal injury from intense chemotherapy and radiation therapy. These cases show that the chest radiograph makes early diagnosis of pneumatosis intestinalis possible in posttransplantation patients.     

儿童肠及肠系膜钝性创伤的CT诊断

目的：探讨CT检查对儿童急性肠及肠系膜钝性创伤的诊断价值。方法：分析11例经临床诊断或手术证实的儿童肠及肠系膜钝性创伤CT表现，全部病例均有明确的腹部外伤史，6例手术治疗，5例保守治疗。结果：11例患者中，胃损伤1例，十二指肠损伤3例，小肠及肠系膜损伤7例。CT表现有气腹、腹腔积液、肠壁肿胀、肠系膜模糊、肠管扩张等。在手术治疗的6例中，胃穿孔1例，小肠穿孔4例．肠壁血肿1例。结论：CT诊断肠及肠系膜急性钝性创伤明显优于X线平片和B超检查。不仅可清晰显示少量腹腔积气，估计腹腔积液、积血的量，显示实质脏器损伤，还可直接显示肠壁、肠系膜血肿，对外科医生确定治疗方案有重要意义。     

Hydrocolonic sonography for evaluating inflammatory bowel disease.

OBJECTIVE: The purpose of our study was to compare the usefulness of hydrocolonic sonography and (99m)Tc-hexamethylpropyleneamine oxime (HMPAO)--labeled leukocyte scintigraphy in the examination of patients with inflammatory bowel disease, using precise sonographic criteria of bowel involvement. SUBJECTS AND METHODS: Sixty-eight consecutive patients with active inflammatory bowel disease (34 ulcerative colitis and 34 Crohn's disease), 12 with inactive inflammatory bowel disease, and 10 control subjects were prospectively studied. Patients with active disease underwent clinical assessment, hydrocolonic sonography, scintigraphy, and colonoscopy within 72 hr, whereas patients with inactive disease and control subjects underwent clinical examination and hydrocolonic sonography. RESULTS: Involvement of a colonic segment by active inflammatory bowel disease was best defined by mucosal thickness greater than 1.5 mm, bowel wall thickness greater than 4 mm, mucosal irregularity, or the absence of haustra; and involvement of the terminal ileum by bowel wall thickness greater than 4 mm. Using these criteria, hydrocolonic sonography had 100% sensitivity for identifying patients with active inflammatory bowel disease and a greater overall accuracy (87%) than scintigraphy (77%) in the assessment of disease extension. In addition, strong correlation was shown between a hydrocolonic sonography activity index and clinical and endoscopic activity indexes. CONCLUSION: This prospective study provides precise sonographic criteria for the definition of bowel involvement by active inflammatory bowel disease. Hydrocolonic sonography has a greater accuracy than scintigraphy for assessing disease extension and activity. Therefore, hydrocolonic sonography should be considered a first-choice technique to complete the study of inflammatory bowel disease after confirmation of the diagnosis by histology.     

Massive pneumatosis intestinalis: CT diagnosis.

Pneumatosis cystoides intestinalis is a rare condition characterized by multiple subserosal or submucosal gas filled cysts within the wall of a segment of bowel. It is associated with numerous conditions, both intra and extraabdominal in nature. The condition may be asymptomatic or may present clinically as nausea, vomiting, diarrhea or other signs of intestinal obstruction. With rupture of the cysts, pneumoperitoneum may be a finding. In a patient with vague clinical presentation, this finding radiographically may lead to a clinical dilemma as many of these patients have comorbid conditions which are also associated with intestinal perforation. The authors present the case of a 47-year-old obese black female found to have massive pneumatosis intestinalis of the tranverse colon with a small amount of free intraperitoneal air. This case highlights the importance of recognizing pneumatosis intestinalis as a possible mimic of free intraabdominal air as well as a possible cause of benign pneumoperitoneum.     

Sonographic findings in infants with suspected necrotizing enterocolitis.

During a three-year period, 27 infants with clinical signs of necrotizing enterocolitis (NEC) underwent ultrasonography; 22 of these infants also had abdominal radiographs within a few hours. Sonographically, portal venous gas (PVG) was seen in 10 and intestinal pneumatosis without PVG in 8 infants. Six children underwent laparotomy within 24 hours after ultrasonography and showed evidence of recent NEC. Three other children, laparotomized weeks later were found to have intestinal strictures as signs of previous NEC. None of the patients died from NEC. Nine infants without abnormal gas distribution did not develop overt NEC. With respect to PVG, sonography is able to support the tentative diagnosis of NEC prior to radiography. However, absence of PVG does not exclude NEC.     

Gastrointestinal perforation: ultrasonographic diagnosis

Gastrointestinal tract perforations can occur for various causes such as peptic ulcer, inflammatory disease, blunt or penetrating trauma, iatrogenic factors, foreign body or a neoplasm that require an early recognition and, often, a surgical treatment.Ultrasonography could be useful as an initial diagnostic test to determine, in various cases the presence and, sometimes, the cause of the pneumoperitoneum.The main sonographic sign of perforation is free intraperitoneal air, resulting in an increased echogenicity of a peritoneal stripe associated with multiple reflection artifacts and characteristic comet-tail appearance.It is best detected using linear probes in the right upper quadrant between the anterior abdominal wall, in the prehepatic space.Direct sign of perforation may be detectable, particularly if they are associated with other sonographic abnormalities, called indirect signs, like thickened bowel loop and air bubbles in ascitic fluid or in a localized fluid collection, bowel or gallbladder thickened wall associated with decreased bowel motility or ileus.Neverthless, this exam has its own pitfalls. It is strongly operator-dependant; some machines have low-quality images that may not able to detect intraperitoneal free air; furthermore, some patients may be less cooperative to allow for scanning of different regions; sonography is also difficult in obese patients and with those having subcutaneous emphysema. Although CT has more accuracy in the detection of the site of perforation, ultrasound may be particularly useful also in patient groups where radiation burden should be limited notably children and pregnant women.     

新生儿胃肠道穿孔的特殊X线征象及价值

目的 探讨新生儿胃肠道穿孔的特殊X线征象.资料与方法 对56例经手术病理证实的新生儿胃肠道穿孔患儿的X线表现进行分析.结果 膈下游离气体39例,无膈下游离气体17例.特殊X线征象表现为:新月征5例、线样征2例、假囊肿征6例、网膜囊积气征1例、足球征19例、镰状韧带征12例、铅笔征2例、胃泡征消失11例、肠壁积气征8例、木梳征1例、气粪混合征2例、腹腔积液征26例、肠间隔增宽征22例、三角形积气征9例等.结论 胃肠道穿孔的特殊X线征象可有助于早期诊断本病.     

Inflammatory bowel disease in children and young adults: correlation of sonographic and clinical parameters during treatment

OBJECTIVE: The objective of this study was to evaluate the sonographic findings of inflammatory bowel disease activity in children undergoing treatment. SUBJECTS AND METHODS: Eighty-eight sonograms were obtained of 23 bowel segments in 17 children and young adults (age range, 10-21 years; mean, 16 years) with new or recurrent inflammatory bowel disease. Sixteen segments were involved with Crohn's disease and seven with ulcerative colitis. Serial sonography (range, two to eight examinations; mean, four per segment) was performed while patients underwent treatment. Bowel wall thickness measurements and color and power Doppler sonography grading were recorded and compared with clinical data. RESULTS: All 17 patients had at least one abnormal bowel segment on initial sonography. The correlation was significant (p < 0.01). Agreement was 91% on direction of change over time between bowel wall thickness and Doppler grades, with 100% correlation between color and power Doppler sonography grades. In patients with Crohn's disease, the correlation was significant (p < 0.05) between bowel wall thickness and Doppler grades with two of seven and four of seven clinical parameters, respectively. In patients with ulcerative colitis, the correlation was significant (p < 0.05) between bowel wall thickness and Doppler sonography grades with four of seven and three of seven clinical parameters, respectively. The erythrocyte sedimentation rate correlated with all sonographic measurements in both patient groups. Combining bowel wall thickness and Doppler sonography, the percentage of agreement was significant in the direction of change, with five of seven clinical parameters in both patient groups. CONCLUSION: Gray-scale and color or power Doppler sonography can show changes in disease activity in children and young adults undergoing treatment for inflammatory bowel disease.     

CT findings of small bowel strangulation: the importance of contrast enhancement

The purpose of this study is to illustrate computed tomography (CT) findings suggestive of small bowel strangulation. We have performed the precontrast and postcontrast CT with single and multidetector CT scanners and evaluated the bowel wall changes and mesentery changes and correlated them with the operative findings. The direct CT findings suggestive of small bowel strangulation included high-density bowel wall on precontrast scans; lack of, or diminished contrast enhancement of the involved bowel wall; localized mesenteric fluid accumulation (mesenteric congestion); and localized pneumatosis. The indirect CT signs included C- or U-shaped loops with mesenteric vessels converging toward the obstruction site, ascites, target sign, two adjacent collapsed round loops, and whirl sign. We particularly emphasize the importance of contrast enhancement of bowel mucosa for early diagnosis to differentiate strangulation from a mechanical obstruction without bowel ischemia, and also the importance to differentiate proximal secondary gas-filled dilated small bowel loops from distal primary involved fluid-filled small bowel loops because these two types of small bowel loops are present in the single peritoneal cavity. As early recognition of small bowel strangulation may help improve the patient outcome because the involved bowel loops can be preserved without resection, it is essential to become familiar with the CT signs suggested small bowel obstruction strangulation.     

Necrotizing enterocolitis: assessment of bowel viability with color doppler US

PURPOSE: To determine whether absence of bowel wall perfusion at color Doppler ultrasonography (US) is indicative of bowel necrosis in neonates with necrotizing enterocolitis (NEC). MATERIALS AND METHODS: This study was approved by the research ethics board, and informed consent was obtained. Sixty-two neonates enrolled in the prospective study underwent US of the bowel wall. Neonates were divided into two groups. Group A included 30 control subjects with gestational ages (GAs) ranging from 24 to 41 weeks. Group B included 32 neonates with GAs ranging from 24 to 40 weeks who were clinically proved to have or suspected of having NEC. All neonates in group B underwent abdominal radiography. Normative values were calculated in group A. In group B, the sensitivities and specificities of color Doppler US and abdominal radiography for detection of bowel necrosis were computed by using the modified Bell staging criteria for NEC as the reference standard. RESULTS: Two neonates were excluded from group B; thus, a total of 60 neonates were included in the study. In group A, bowel wall thickness ranged from 1.1 to 2.6 mm. Bowel wall perfusion was detected with color Doppler US in all 30 neonates. Color Doppler signals ranged from one to nine dots per square centimeter. Twenty-two of 30 neonates in group B received a diagnosis of NEC. Mild to moderate NEC was diagnosed in 12 neonates. Color Doppler US depicted an isolated segment of bowel-absent blood flow in two neonates; this finding was confirmed with laparotomy. In 10 neonates with severe NEC, color Doppler US depicted isolated or multiple segments of bowel with absent perfusion. Pneumoperitoneum was present in only four neonates. The remaining eight neonates at risk for NEC had no evidence of loops without perfusion at color Doppler US. The sensitivity of free air at abdominal radiography as a positive sign for severe NEC with necrotic bowel was 40% compared with the 100% sensitivity of absence of flow at color Doppler US (P = .03). CONCLUSION: Color Doppler US is more accurate than abdominal radiography in depicting bowel necrosis in NEC.     

Small bowell volvulus - combined radiological findings]

PURPOSE: We retrospectively evaluated the radiological findings observed at plain abdominal film, abdominal sonography and abdominal CT performed in 66 patients with surgically proven small bowel volvulus. MATERIAL AND METHODS: Sixty-six patients (35 women and 31 men, ranging in age 38-77 years) with surgically proven small bowel volvulus were submitted to plain film, sonography and CT of the abdomen. Abdominal plain film was performed in the upright position (postero-anterior view) in 46 cases, and in the supine position in 20 cases. On plain abdominal film we evaluated the following findings: bowel loops dilatation, air-fluid levels and site of obstruction. At abdominal US, performed with 3.5 e 7.5 MHz probes, we retrospectively searched for: bowel loop dilatation, bowel wall thickening, peristalsis alteration, extraluminal fluid. CT was performed with a helical unit (thickness 4 mm, reconstruction interval 4 mm, pitch 1.5), after intravenous contrast agent (120 ml) infusion (3 ml/s, 55 s acquisition delay from bolus starting) and using a power injector. The following CT findings were searched for: whirl sign, beak sign, extraluminal fluid, bowel loop dilatation, bowel wall thickening, bowel wall or mesenteric alterations. RESULTS: Plain abdominal film showed the following findings: air-fluid levels (92.4% of cases), bowel loops dilatation (71.2%), site of obstruction (42.4%). Abdominal sonography demonstrated bowel loop dilatation (48.5%), extraluminal fluid (48.5%), peristalsis alteration (27.3%), bowel wall thickening (27.3%). The most frequent CT findings were: bowel loop dilatation (95.5%), bowel wall thickening (78.8%), beak sign (69.7%), mesenteric alterations (66.7%), extraluminal fluid (54.5%), whirl sign (13.6%). CONCLUSIONS: Air-fluid levels and bowel loop dilatation were the most frequent radiological findings in our series. Plain abdominal film allowed us to identify signs of obstruction, whereas signs of bowel wall necrosis were accurately shown by abdominal CT.     

绞窄性肠梗阻的螺旋CT增强扫描征象分析

目的:分析螺旋CT增强扫描图像上绞窄性肠梗阻的征象,提高对绞窄性肠梗阻术前诊断的准确性.方法:64例手术证实的绞窄性肠梗阻病例纳入研究,男43例,女21例,年龄23～72岁,平均42岁.采用单排螺旋CT进行全腹部扫描,对比剂以2～3ml/s速度注射,注射后60s扫描,层厚10mm.参照术中所见,回顾性分析上述CT资料,包括:①间接征象:肠腔扩张积液,肠壁增厚及肠壁密度改变(靶征),肠系膜脂肪水肿及渗出(缆绳征),肠系膜血管增粗并肠系膜扭曲(漩涡征),肠壁间、肠系膜间及门静脉积气,腹水;②直接征象:肠系膜上动脉或上静脉充盈缺损.结果:正确诊断54例,正确率82.8％.CT显示肠腔扩张积液47例(73％),其中6例积液呈高密度提示肠腔内积血(9.3％);肠壁水肿增厚19例(29.6％),其中11例增强后肠壁密度不匀,呈“靶征”(17％),8例肌壁未见强化(12.5％);肠系膜脂肪水肿及渗出(缆绳征)43例(67％),肠系膜血管增粗并肠系膜扭曲呈“漩涡”状9例(14％),肠壁间积气、肠系膜积气各1例,门静脉积气2例,腹水31例(48.4％).肠系膜上动脉或上静脉充盈缺损3例.结论:绞窄性肠梗阻CT表现有一定特征,可做出提示性诊断.     

Significance of bowel wall enhancement on CT following blunt abdominal trauma in childhood.

Over a 3-year period, 12 children with blunt abdominal trauma were noted to have intense bowel wall enhancement (BWE) on CT. In four, with fatal CNS injury, there was no evidence of bowel perforation, and the changes may be related to the hypovolemic complex. In the remaining eight patients with a gastrointestinal perforation, BWE was associated with the presence of diffuse or focal bowel wall thickening and free peritoneal fluid. The enhancement and thickening were due to peritonitis secondary to perforation as shown at operation or autopsy. In three further patients with bowel perforation, thickening and enhancement were absent in two with retroperitoneal perforation and thickening, and no enhancement was noted in one patient in whom the study was considered suboptimal in retrospect. Intense BWE, therefore, aids in the diagnosis of the hypovolemic complex: CNS injury and bowel perforation. When combined with bowel thickening and free fluid, perforation and peritonitis should be strongly suggested. Enhancement and thickening should suggest perforation even if other visceral injury is present to account for the free fluid. Surgical intervention should thus be more strongly considered when bowel wall thickening accompanies BWE.