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Answer
Cecal volvulus: The initial scout image (see Image 1) demonstrates a markedly dilated segment of bowel with a kidney- or coffee-bean appearance. The vector of the C-loop points toward the right lower quadrant and suggests a cecal volvulus. The axial CT image (see Image 2) demonstrates a colon dilated to 8 cm, with an air-fluid level. The collapsed ascending and transverse colon are adjacent to the dilated bowel (arrow).
The patient underwent exploratory laparotomy for the bowel obstruction and suspected cecal volvulus without a preoperative attempt at reduction. The cecum was edematous, with a dusky appearance (see Image 3). A floppy segment of bowel not adherent to the lateral wall had folded upward into the upper abdomen and twisted around; these observations were consistent with a final diagnosis of cecal volvulus. The volvulus was reduced, and the color of the involved bowel improved ("pinked up") nicely (see Image 4). Right colonic resection was performed (because of risk of recurrence and underlying ischemic damage having already occurred even though flow may be restored) with stapled ileocolostomy without complication. Pathology revealed ischemic changes, with marked dilatation and serosal adhesions; no perforation was observed. The patient recovered uneventfully.
Cecal volvulus is a condition characterized by twisting or folding of the right colon. Volvulus of the large bowel is the cause of approximately 10% of large-bowel obstructions. Cecal volvulus represents approximately 1-2% of intestinal obstructions and about one third of all cases of colonic volvulus. (Most cases are due to sigmoid volvulus.) Cecal volvulus occurs predominantly in patients with poor right colon xation (found in 10-25% of the general population) and is due to excessive cecal mobility.
Patients with cecal volvulus usually present with an acute onset of severe, colicky pain with nausea and vomiting unless partial obstruction is present or unless the volvulus is intermittent; in these cases, the onset may be relatively insidious. Abdominal distention may or may not develop. Sudden distention of the cecum due to trauma, laxative use, constipation, postpartum ligamentous laxity, or distal colonic obstruction are proposed etiologies. Cecal volvulus also occurs in a variety of other clinical situations, such as after colonoscopy or barium enema study and in pregnancy.
An abdominal series alone helps in diagnosing approximately 50% of all cases of cecal volvulus. Radiographs show a single air-fluid level in a dilated air-filled cecum in the mid abdomen or left upper quadrant. The cecal valve may produce a soft-tissue indentation, creating a coffee-bean or kidney-shaped appearance to the air-filled cecum. The small bowel should be dilated or fluid filled unless the process is early in its course and collapsed. If abdominal radiographs are nondiagnostic, CT scanning or contrast enema study helps in further defining the condition. Barium enema study can show beaking at the point of the volvulus in the mid ascending colon. CT scans show the volvulus itself and progressive tapering of the afferent and efferent limbs, which leads to a twist; this is described as the whirl sign.
Approximately 90% of patients with cecal volvulus have an axial twist of an ascending segment of the colon; this has been called a type 2 volvulus. About 10% have a cephalic fold of the cecum across the ascending colon in the transverse plane, or a type 1 volvulus (also referred to as a cecal bascule). The etiology of type 1 is controversial. Some believe that patients with type 1 volvulus have a focal adynamic ileus of the cecum, whereas some think that the cause is an adhesive band due to previous abdominal surgery.
Treatment usually consists of surgical reduction with or without colonic resection and ileocolostomy. Nonsurgical techniques, such as barium enema and colonoscopy, are less successful for reducing cecal volvulus than for sigmoid volvulus, and the rate of associated perforation is higher with a cecal volvulus than with a sigmoid volvulus. Nonsurgical reduction may be most successful in type 1, or cecal bascule type. Although treatment and management of both types is the same, a type 2 volvulus increases the risk of vascular compromise and perforation. Perforation occurs in 65% of cases involving mechanical distention combined with a vascular compromise. Gangrene is observed in as many as 20% of patients, and the mortality rate is estimated to be as high as 20-40% in the elderly.
For more information on cecal volvulus, see the eMedicine articles Cecal Volvulus (within the Radiology specialty) and Obstruction, Large Bowel (within the Emergency Medicine Specialty).
References
- Brant WE, Helms CA. Fundamentals of Diagnostic Radiology. Philadelphia, Pa: Lippincott Williams & Wilkins; 1999.
- Ferderle M, Jeffrey RB, Anne VS, Erasco A. Diagnostic Imaging: Abdomen. Amirsys: Salt Lake City, UT; 2004.
- Khan AN. Cecal volvulus. eMedicine Journal [serial online]. Available at: http://www.emedicine.com/radio/topic137.htm. June 29, 2005. Accessed July 18, 2006.
- Weissleder R, Wittenberg J, Harisinghani MG. Primer of Diagnostic Imaging. St Louis: Mosby; 2003.
A 46-year-old woman presents to the emergency department with a history of worsening, constant right upper quadrant pain that radiates to her back and side. She has had nausea and vomited twice the past several hours. She underwent laparoscopic cholecystectomy 2 weeks ago, without complications, and returned to her normal diet. She has not had any bowel movements or the passage of flatus since the pain began. She denies having fever, chills, or rigors. Her medical history is significant only for high blood pressure, high cholesterol levels, and gallbladder disease. She takes lisinopril, aspirin, multivitamins, and ginseng. She denies smoking or drinking alcohol.
On physical examination, the patient is awake, alert, and oriented. Her vital signs are in the normal range, with a heart rate of 84 beats per minute and a blood pressure of 124/76 mm Hg. She appears to be in mild distress. Cardiorespiratory examination yields normal findings, with clear lungs and a regular heart rhythm. Her abdomen is soft, but her bowel sounds are decreased, and she has marked tenderness in the right upper quadrant. The rest of her abdomen is minimally tender, with no evidence of guarding or rebound and no palpable masses. Other physical findings are normal.
Laboratory investigation reveals an elevated WBC count of 14.0 X 109/L (14.0 X 103/µL) with a left shift of 87% neutrophils. Her liver function tests, lipase level, and basic chemistry panel are unremarkable.
Contrast-enhanced CT of the abdomen and pelvis is ordered. Images 1 and 2 show an anteroposterior (AP) scout image and a selected axial section, respectively.
What is the diagnosis?
Hint
This entity is commonly described as various foods, specifically "beans".
Author: Craig Johnson, DO, Diagnostic Radiology Residency Program, Northeastern Ohio Universities College of Medicine-Canton Affiliated Hospitals
Rathachai Kaewlai, MD, Emergency Radiology Fellow, Massachusetts General Hospital-Harvard Medical School
Kenneth Nazinitsky, MD, Assistant Professor of Radiology, Diagnostic Radiology, Northeastern Ohio Universities College of Medicine-Canton Affiliated Hospitals
eMedicine Editor: Rick G. Kulkarni, MD, Assistant Professor, Yale School of Medicine, Section of Emergency Medicine, Department of Surgery, Attending Physician, Medical Director, Department of Emergency Services, Yale-New Haven Hospital, Conn
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