Cause Of Intussusception Research Articles

Characteristics of intussusception among children in Korea: a nationwide epidemiological study

BackgroundIntussusception is a gastrointestinal condition in which early treatment is critical. Although its epidemiology and comorbidities have been studied, few studies have included the entire pediatric population of a country. Therefore, we aimed to analyze the epidemiologic features of pediatric intussusception patients and identify comorbidities associated with intussusception in South Korea, using the public health database.MethodsWe analyzed the data of children below 18 years of age, from the national database of South Korea, who were diagnosed with intussusception and managed such as air reduction or surgical methods from 2008 to 2016. Patients were categorized into six groups based on the comorbid diseases. Patients with structural lesion in gastrointestinal tract were divided diagnosis or diagnosis code.ResultsThe number of patients diagnosed with intussusception were 25,023 (16,024 males, 64.0%). Of them, the highest percentage was patients aged between 2 and 36 months (20,703; 82.7%). The incidence per 100,000 individuals aged up to 2 years was 196.7. The number of males were 16,024 (64.0%) and were almost twice the number of 8999 (36.0%) female patients. The maximum number of cases (n = 2517; 10.1%) were seen in September, followed by July (n = 2469; 9.9%). In February, the number of cases was lowest at 1448 (5.8%) patients (P < 0.001). The number of patients with structural lesions of the gastrointestinal tract that could lead to intussusception was 1207 (4.8%), while patients with acute gastrointestinal infectious disease were 4541 (18.1%). Among the structural lesions of the gastrointestinal tract that could be the leading cause of intussusception, lymphadenopathy was the most common, seen in 462 (56.6%) patients and an appendix-related condition was seen in 260 (31.9%) patients. Infectious diseases were more common in the younger children, while systemic diseases were more common in the older.ConclusionWe confirmed that pediatric intussusception in South Korea shows a seasonal tendency, which is age-dependent and is associated with an exposure to infectious agents. Some infectious pathogens and underlying diseases might play an important role in the pathophysiology of intussusception.

Intussusception secondary to inflammatory myofibroblastic tumor of the small intestine. Case report

Introduction: Intussusception occurs when part of the intestine slides into an adjacent intestinal segment. Inflammatory myofibroblast tumor is a rare cause of this condition, and is observed in 5% -16% cases in adults.Case presentation: A 41-year-old woman presented with abdominal pain and distension. A exploratory laparoscopy was performed, finding ileocolic intussusception into the transverse colon. Due to uncontrollable bleeding, the procedure was converted to laparotomy; resection and latero-lateral ileocolic anastomosis were performed. Histopathology reported inflammatory myofibroblastic tumor, with a favorable postoperative evolution. The patient was discharged on the sixth postoperative day.Discussion: When located in the small intestine, 57% of the tumors that cause intussusception are benign, including the myofibroblastic tumor in this patient. The symptoms and signs associated with this neoplasm are cramp-like abdominal pain, nausea and vomiting. Although imaging studies may lead to suspect this diagnosis, in most cases it is made intraoperatively. Surgical resection of the affected intestinal segment is curative, with favorable prognosis.Conclusions: This case is considered as a rare cause of intussusception. It had a benign course and is still under study since its pathophysiology has not been fully understood.

Retrograde intussusception post-total gastrectomy and small bowel resection with Roux-en-Y gastric bypass reconstruction

Intussusception is a rare cause of intestinal obstruction, especially in adult populations. Adult intussusception was traditionally thought to occur secondary to a pathological lead point such as a malignancy, inflammatory bowel disease, or anatomic abnormality; for example, a Meckel’s diverticulum. Intussusception is a rare surgical complication post Roux-en-Y gastric bypass. An increase in incidence is found with increasing demand of bariatric surgeries. The exact cause of intussusception is unclear. We present a 86-year-old female with retrograde small bowel intussusception posttotal gastrectomy and small bowel resection with Roux-en-Y reconstruction.

A rare clinical case of retrograde small-bowel intussusception in pediatric practice

Intestinal intussusception in children is a mixed variant (with elements of obstruction and strangulation at the same time) of intestinal obstruction caused by isoperistaltic insertion of the proximal intestine into the distal. The article describes a rare clinical case of retrograde small bowel intussusception in a teenage girl aged 17 years with severe neurological pathology. Anamnesis, clinical symptoms and results of paraclinical methods of research, methods and results of the conducted treatment are given. The aim of the article is to familiarize doctors of practical health care with an extremely rare variant of intestinal intussusception. Retrograde (antiperistaltic) small bowel intussusception in children is very rare. Given the neurological status of the patient, the probable cause of intussusception was spastic neurogenic small intestinal dyskinesia. The direct cause of the disease was feeding mistakes in the form of feeding large amounts of strained food through the gastrostomy.

Location of Intussusception in Adults Predicts Malignant Etiology

Introduction: Intussusception is defined by a proximal segment of the gastrointestinal tract invaginating into a more distal portion of bowel. This results in obstruction or intestinal vasculature compression which can lead to ischemia, infarction, or even perforation. Adult intussusception is a rare, accounting for 1-5% of the total intussusception cases. Identifiable structural lesions or lead points are identified in up to 30% of cases. In adults, close to 30-50% of all the cases are related to malignancy. Celiac disease has also been reported as a possible etiology for adult intussusception. Methods: We reviewed the records of all patients 18 years and older with an ICD-9 code of intussusception between 01/2010 - 05/2018. Patients with a diagnosis of rectal and gastric intussusception were excluded. Data was obtained from a review of patient charts, operative and pathology reports. Age, gender, race, proximal bowel dilation, and presence of celiac disease were recorded. Cases were categorized based on location and etiology (no neoplasm vs neoplasm). Univariate and multivariate regression analysis were conducted to identify predictors of neoplasm in these cases. Results: A total of 67 cases were identified, with 61% male, mean age of 50 years and 70% white. Small intestine was the site of intussusception in 54 cases (81%) as compared to 13 cases (19%) of colonic intussusception (Table-1). Proximal bowel loop dilation was seen in 25% of cases. 3 patients (4.5%) had associated Celiac disease. Neoplasms were the cause of intussusception in 22% of the cases. 77% of colonic intussusception cases were caused by neoplasms as compared to 9% of the small intestinal intussusception. Patients with neoplasms were older (57.7 versus 49 years). In both univariate and multivariate analysis, colonic location of intussusception was a significant predictor of malignancy with odds ratios of 33 (CI: 6.7-166) and 32 (CI: 6.7-159) respectively. Conclusion: Although small intestinal intussusception is more frequent in adults, colonic intussusception is more frequently associated with neoplasms. Patients with advanced age also have a higher incidence of neoplasms as the cause of intussusception. This reinforces the importance of a more comprehensive investigation for older adults who present with colonic intussusception.160 Figure 1 No Caption available.

Clinical analysis of 23 cases with adult intussusception

Objective To analyze the pathogenesis, type, diagnosis and surgical methods of adult intussusception. Methods The clinical presentation, diagnosis and therapeutic management of 23 patients admitted with the diagnosis of intussusception in Kunshan First People′s Hospital Affiliated to Jiangsu University from January 2014 to March 2017 were reviewed retrospectively. Results For all patients, Symptom included paroxysmal bellyache (22/23), abdominal mass (7/23), nausea and vomit (2/23). Twenty one patients received operation, and all discharged from hospital. Malignant neoplasm, benign tumor, diverticulum, inflammation and fecal stone were main cause for intussusception. Conclusion Most of adult intussusceptions are secondary lesions, with complex pathologic condition and non-specific symptoms. CT scanning has been proved to be the most useful diagnostic radiologic method. Surgery is the main treatment of adult intussusception. As for patients recevied conservative treatment and intraoperative exploration with no obvious lesions, endoscopy is necessary postoperative. Key words: Diagnosis; Treatment; Disease attributes; Adult intussusception; Etiology

Intussusception followed by intestinal obstruction in adults

To evaluate the effectiveness of complex preoperative diagnostics and medication of intussusception followed by intestinal obstruction in adults with the choice of surgical repair and analysis of the outcomes depending on the causes of intussusception. 15 intussusception patients aged 19 - 86 years were enrolled. Mean age was 52.7 years. Patients were hospitalized within 12 hours - 1-2 weeks after onset of the disease. Diagnosis was established on the basis of complaints, anamnesis, objective and additional survey. All patients underwent abdominal X-ray and ultrasound. Intestinal obstruction at admission was diagnosed in all patients, and only 1 (6.7%) of them had intussusception. Medication and additional survey contributed to detection of intussusception followed by intestinal obstruction in 13 (86.7%) out of 15 patients prior to surgery. All patients underwent urgent or delayed surgery. Small intestine resection was performed in 9 patients, 2 patients underwent resection of small intestine with submucosal tumor (1) and Meckel's diverticulum (1) after intussusception repair. Right-sided hemicolectomy was performed in 3 patients, sigmoid colon resection with lymph nodes dissection - in 1 patient. The cause of intussusception followed by intestinal obstruction were epithelial and stromal tumors (9), less often metastasis of melanoma (2), Meckel's diverticulum (1) and functional bowel disorders (1). Postoperative complications arose in high risk patients hospitalized after 24 hours from onset of the disease and present concomitant diseases and malignancies. 1 (6,7%) patient died.

Adult intussusceptions in descending colon: An uncommon occurrence

Intussusception is a rare event in adults which constitutes 1–3% of all cases of intestinal obstruction. Malignant etiology as causes of intussusception is more common in large bowel accounting for 60–65% cases. Intussusception due to colonic lipoma is rare. The present case is a 45-year-old woman who had a polypoidal growth in the descending colon. She was operated and the growth was histopathologically diagnosed as lipoma. Though rare, colonic lipoma should be considered as a probable etiology for intussusceptions.

A Case Report on Post-Operative Intussusceptions in Adult

Intussusception is the prolapse of one part of the bowel into the lumen of the immediately adjoining part. Intussusceptions in adults are much less common, representing 5% of all intussusceptions, 1% of all bowel obstructions, and 0.08% of all abdominal surgery. Surgery as a possible cause of intussusceptions in children is very rare (0.05%) and in adult, there are very few reports. In a report in a mayo clinic only 73 cases were seen within 23 year. This case report will be one of the few case reports on the subject matter. This is a 30 year old female from rural areas who underwent laparotomy and cystectomy for the diagnosis of left side ovarian cystic torsion after she presented with right side abdominal pain of sixth days duration which was squeezing in type. On the fourth post-operative day she started to have abdominal distention, and vomiting which was non projectile bilious matter 4-5 times/day. She came after 4 days of these symptoms with failure to pass both feces and flatus. On the day of admission she has 3-4 episodes of watery diarrhea which was blood tingled. Physical examination she was acutely sick looking and dehydrated. Abdominally she has centrally distended abdomen with palpable bowel loops and visible peristalsis. We investigated her with abdominal X-ray and ultrasound which suggested SBO 2ry to intussusceptions. After stabilizing the patient we did laparotomy. Intraoperativly we found viable ileo- ileal intussusceptions at two sites with distended bowel loops proximal and collapsed bowel loops distal to the intussusceptions. She had smooth post op course and discharged improved. The case is extremely important for the study of this possible differential in post-operative period because a delayed or incorrect diagnosis of acute intussusceptions can have serious consequences. Moreover it serves as an input for future studies in the area.

Invagination Intestinale Aiguë De L’adulte: Aspects Diagnostiqsues, Thérapeutiques Et Étiologiques

Introduction: Acute intussusception is a rare clinical entity in adults where it accounts for only 1-2% of intestinal obstructions. The authors wanted to report cases of acute intussusception in adult patients, their diagnostic aspects, their management, and their etiologies. Patients and Methods: This study is a retrospective study of the medical files of patients of both sexes. They include adults over 15 years of age, operated between January 2010 and December 2014, who were diagnosed with obstruction due to acute intestinal intussusception. Results: Six cases of adult intestinal intussusception were collected. The average age was 26.5 years. The sex ratio was 1 and there were so many men as women. Five out of six patients were unstable on admission. The diagnosis was made preoperative in two cases out of six, 33.3%. Ultrasound revealed a target sign in two cases. The ileo-ileal form was the most frequent (5 cases out of 6) or 83.3%. Also, there were two cases of intestinal necrosis out of six. Intestinal resection was performed in five cases or 83.33%. The cause of intussusception was found in four cases out of six or 66.7%. Here, a tumor was the cause in half of the cases. Immediate surgical follow-up was uncomplicated in all patients. Conclusion: Acute intestinal intussusception of the adult is a very rare condition. The preoperative diagnosis of acute intussusception of the adult remains delicate. The ileo-ileal form is more frequent than the ileo-colic form in adults. Treatment is always surgical in adults.

Salmonella enteritis: A Rare Cause of Adult Intussusception.

Intussusception is a relatively rare condition in the adult population and is commonly secondary to a malignant process. Eight to twenty percent of cases of adult intussusception are thought to be idiopathic. In children, infection has been proven to precipitate intussusception in the absence of any other cause. We present a rare case of intussusception in a healthy adult patient secondary to salmonella infection and discuss infection as a potential explanation for a proportion of the cases of adult intussusception that are thought to be idiopathic. We recommend testing for infective causes of intussusception in adults when more common causes, such as malignancy, have been excluded.

Endoscopic Treatment of Jejunal Heterotopic Gastric Mucosa that Caused Recurrent Intussusception.

Heterotopic gastric mucosa (HGM) is a rare anomaly in the small bowel and may be the cause of intussusception when it gets a lead point in the jejunum. All cases of intussusception due to intestinal HGM have been treated with surgical resection. A 5-year-old girl presented with chief complaints of vomiting and abdominal pain for 2 weeks. A computed tomography scan of the abdomen showed intussusception at the proximal jejunal loops. Three air reductions and one saline reduction were attempted without success. She continued to be symptomatic, and endoscopic evaluation was performed. Enteroscopy revealed some variable-sized polypoid mucosal lesions with erosions on the proximal jejunum. Endoscopic mucosal resection was performed using a snare. The resected tissues histologically showed a hyperplastic polyp arising from the HGM. Her symptoms did not recur within 1 year after the treatment. Our case showed that enteroscopy could be useful for the diagnosis and management of jejunal intussusception caused by HGM.

A5269 - Biliopancreatic blind limb as a rare cause of intussusception at the jejunojejunostomy after Roux-en-Y gastric bypass

A5269 - Biliopancreatic blind limb as a rare cause of intussusception at the jejunojejunostomy after Roux-en-Y gastric bypass

An unusual cause of intussusception in a child

An unusual cause of intussusception in a child

Adenovirus-Associated Acute Appendicitis: An Under-Recognized Relationship?

Acute appendicitis (AA) is one of the most common causes of a surgical abdomen worldwide, occurring most frequently in those age 10 to 29 years. Adenovirus (ADV) is a rare but reported cause of AA in children and a well-recognized cause of intussusception in infants and young children. Annually, about 36,000 basic military trainees (BMTs) undergo initial training at Joint Base San Antonio Lackland, Texas. Before reintroduction of the ADV 4/7 vaccine in November 2011, one-third of BMTs developed an adenoviral upper respiratory tract infection (URI) during the 8.5 weeks of training. We hypothesized that ADV may be a common cause of AA in the BMT population given their young age and high incidence of adenoviral URIs. The objective of this study was to determine the frequency with which ADV, cytomegalovirus (CMV), Epstein-Barr virus (EBV), and enterovirus were associated with AA in a population of young adults. This study was a retrospective review of patient charts and existing pathological tissue specimens of all BMTs who underwent appendectomy at the Wilford Hall Medical Center from January 1, 2003, to August 31, 2011. Pathological tissue samples from 112 BMTs were assayed by quantitative polymerase chain reaction (qPCR) and immunohistochemistry (IHC) for viral targets. ADV DNA was detected in 16 of 112 samples (14%) via qPCR: ADV 4 in 13 cases, ADV B14 in 1 case, and nontypable ADV in 2 cases. IHC was positive in only the ADV B14 case (0.9%). All cases were negative for CMV, EBV, and enterovirus. By using qPCR, this study demonstrated an association between ADV and AA higher than has been previously reported: ADV was detected in 14% of AA cases in this series versus in only 0.23% of AA cases in previous studies (p < 0.01). There was no evidence of CMV, EBV, or enterovirus association with AA in this study. Comparison of qPCR to IHC shows that histologic analysis may overlook evidence of ADV in appendiceal tissue: qPCR is significantly more sensitive than light microscopy and IHC for detecting ADV in this setting. Because ADV 4 was detected in 81% of those with positive qPCR, the recently licensed live oral ADV vaccine might be useful for primary prevention against AA. Prospective studies evaluating young adults presenting with AA for evidence of infection with ADV are needed to determine if a causal relationship exists.

Hospitalization rates for intussusception in children aged 0–59 months from 2009 to 2014 in Italy

ABSTRACTThe real cause of intussusception is not fully understood and a variety of conditions have been associated with it (Meckel diverticulum, polyps, duplication cysts, parasites, Henoch-Schönlein purpura, cystic fibrosis, hemolytic-uremic syndrome and infectious gastroenteritis). Furthermore few European countries, following WHO recommendation to monitor baseline incidence of intussusception before implementation of immunization program for rotavirus, used intussusception rate as a baseline value to compare the same figures in the period before and after introduction of vaccination. In this study, data of intussusception hospitalizations occurred among Italian children aged 0 through 59 months from 2009 to 2014 were analyzed.A total amount of 3,088 children were included, accounting for a hospitalization rate of 20.2 per 100,000. Overall, the hospitalization rate for intussusception had a slight increase in trend from 2009 to 2014 (18%). In particular children 0–11 months had a hospitalization rate higher than 12–59 months with an aggregate value of 36 Vs. 16 per 100,000 respectively. Among all children hospitalized for intussusception a total of 239 (7.7%) had also a previous or concomitant hospitalization for gastroenteritis.This study demonstrates that Italian hospitalizations for intussusception are increasing by time and the role played by different risk factors, including acute gastroenteritis, have to be investigated in the future. These data could be useful to monitor intussusception hospitalization in the perspective of anti-rotavirus vaccination introduction in Italy.

Burkitt lymphoma as a cause of intussusceptions: The significance of positron emission tomography scan in the follow-up

Introduction. Burkitt lymphoma (BL) is a high-grade, highrisk type of non-Hodgkin lymphoma characterized by a very rapid cell progression. Although BL is a rare cause of intussusceptions, it must arouse suspicion if the intussusception occurs outside the characteristic peak. Case report. A previously healthy 7-year-old boy was hospitalized for recurrent abdominal pain, loss of appetite and body weight, a fever of up to 38?C, persistent vomiting and with soft tumefaction ileocecally. Nuclear magnetic resonance (NMR) revealed intussusceptions due to a tumor mass, which was followed by a surgical procedure (right hemicolectomy and terminoterminal anastomosis). Histopathological examination confirmed the diagnosis of primary abdominal Burkitt lymphoma. In spite of the subsequent oncologic treatment lasting for four months, an undifferentiated mass was detected in the retroperitoneal space below the lower pole of the right kidney. Positron emission tomography (PET) scan was performed in order to detect the metabolic activity of the deposit in the retroperitoneal space. A high metabolic activity of Burkitt lymphoma confirmed its presence, as well as the need for additional surgical intervention for tumor extirpation. PET scan undoubtedly contributed to distinguishing the visibility of tumor cells and to the detection of the subcentimeter tumor mass. Conclusion. The timely diagnosis, high tumor sensitivity to chemotherapy as well as the great importance of PET scan in the early detection of tumor recurrence, significantly increase the survival rate in patients with BL.

Failed Intussusception Reduction in Children: Correlation Between Radiologic, Surgical, and Pathologic Findings.

The objective of this study was to identify causes of irreducible intussusception after contrast enema and to correlate imaging findings with surgical and histopathologic findings. Between 2005 and 2013, a total of 543 children underwent reduction of intussusception with the use of an enema technique (hereafter referred to as "enema reduction"). The medical records of 72 children (56 boys [mean age, 24.8 months; range, 3.8 months to 10.9 years] and 16 girls [mean age, 14.2 months; range, 1.5 months to 6.9 years) who underwent unsuccessful reduction and were treated surgically were retrospectively analyzed. The data collected included information on the cause of intussusception, the risk factors noted on ultrasound, operative management, outcome, and the length of the hospital stay. The imaging findings for these patients were compared with findings for statistically similar age-matched control subjects. Ultrasound detected 56 of 57 cases of intussusception, but it failed to detect the lead point in three cases and failed to detect ischemic necrosis in seven cases. Positive predictors of failed enema reduction were the presence of a distal mass and observation of the dissecting sign. Of the 72 patients who underwent surgical treatment of intussusception, 26 (36.1%) underwent laparoscopy, 38 (52.8%) underwent laparotomy, and eight (11.1%) underwent conversion from laparoscopy to laparotomy. Surgical reduction was performed in 61.1% of cases, small bowel resection in 19.4%, ileocecectomy in 12.5%, and self-reduction in 69%. Pathologic lead points (noted in 25% of cases) included lymphoid hyperplasia (n = 7), Meckel diverticulum (n = 3), Burkitt lymphoma (n = 3), enteric duplication cyst (n = 2), juvenile polyp (n = 2), and adenovirus appendicitis (n = 1). The length of the hospital stay was significantly longer after laparotomy. The distalmost location of the intussusception mass and presence of the dissecting sign on images obtained during contrast enema have a higher positive predictive value for failed reduction. Screening ultrasound decreases the number of unnecessary contrast enemas performed; however, classic pathologic lead points, such as Burkitt lymphoma and Meckel diverticulum, may be difficult to diagnose with the use of ultrasound. Laparotomy and laparoscopy are equally safe and efficacious in reducing intussusception, with the length of the hospital stay after laparoscopy significantly shorter than that noted after laparotomy. Most failed enema reductions are idiopathic, and pathologic lead points are noted in 25% of cases.

Is intestinal malrotation the cause of intussusception? Waugh's syndrome, a case report

Waugh's syndrome is the combination of intussusception and intestinal malrotation. The first case was described in 1911, with few cases being reported since then. A 7 month-old infant with fever, vomiting and rectal bleeding. Distension and an abdominal mass was found on examination. An exploratory laparotomy was preformed that found a combination of intussusception and intestinal malrotation, which was treated successfully. We consider that this combination is not sufficiently diagnosed very often, leading to its disappearance. El síndrome de Waugh se define como la asociación de invaginación y malrotación intestinal. Los primeros reportes de este síndrome fueron en el año 1911 y, a pesar de esto, existen muy pocos casos descritos. Conocer la asociación que existe entre la invaginación y la malrotación intestinal como causa de obstrucción intestinal en el lactante. Lactante varón de 7 meses de edad, que ingresa en urgencias por: fiebre, vómito y evacuaciones mucosanguinolentas. En el abdomen con: dolor, distensión, palpándose «morcilla» en cuadrante inferior izquierdo al tacto rectal con evacuaciones en «jalea de grosella». Se realiza laparotomía exploradora encontrando una relación entre invaginación y malrotación intestinal resuelta quirúrgicamente. Consideramos que esta asociación no se diagnostica de forma adecuada, pasando normalmente desapercibida.

Adult Female With Abdominal Pain

A 34-year-old woman with a history of fibroids presented to the emergency department with 4 days of intermittent abdominal pain. She described 1 episode of emesis and 1 loose watery stool. She denied fevers, urinary symptoms, or vaginal complaints. Her physical examination result was notable for mild periumbilical tenderness to palpation without rebound or guarding. Her pelvic examination result was unremarkable. Blood work, urinalysis, and pregnancy test results were negative. The emergency physician initially performed bedside ultrasonography (Figure 1), and computed tomography (CT) was subsequently obtained (Figure 2).Figure 2Coronal (left panel) and sagittal (right panel) CT images demonstrate intussusceptum (short arrow) and surrounding intussuscipiens (long arrow).View Large Image Figure ViewerDownload Hi-res image Download (PPT) Intussusception. Bedside ultrasonography demonstrated a hypoechoic external ring with a hyperechoic crescent, which was confirmed by the CT. Air insufflation was unsuccessful and a hemicolectomy was ultimately performed. Biopsies revealed adenocarcinoma of the colon. Intussusception is an emergent abdominal condition that is characterized by the telescoping of one part of the intestine into an adjacent part during peristalsis. If left untreated, intussusception can lead to bowel obstruction, bowel necrosis, perforation, or infection. Most cases (95%) are diagnosed in children.1Choi S.H. Han J.K. Kim S.H. et al.Intussusception in adults: from stomach to rectum.AJR Am J Roentgenol. 2004; 183: 691-698Crossref PubMed Scopus (66) Google Scholar The majority of adult patients who receive a diagnosis of intussusception require operative intervention because they usually present late in the course of the disease.2Marinis A. Yiallourou A. Samanides L. et al.Intussusception of the bowel in adults: a review.World J Gastroenterol. 2009; 15: 407-411Crossref PubMed Scopus (394) Google Scholar The most common cause of intussusception in adults is a primary neoplasm of the colon. Ideally, the emergency physician uses the curvilinear transducer to evaluate the loops of bowel where the patient is most tender. The “crescent in a doughnut sign,” characterized by a hypoechoic external ring with a hyperechoic crescent, is the most common sonographic appearance of intussusception.3Tiao M.M. Wan Y.L. Ng S.H. et al.Sonographic features of small-bowel intussusception in pediatric patients.Acad Emerg Med. 2001; 8: 368-373Crossref PubMed Scopus (50) Google Scholar