Diagnosis
Cecal bascule with concurrent acute appendicitis
Findings
A supine abdominal radiograph with distended bowel loops in the right
flank and epigastric region. Lateral CT/scout shows distended large
bowel with fluid levels (note haustra) (Figure 2). Scanogram shows
distended bowel with haustra oriented vertically at the epigastrium, and
measuring > 9 cm in diameter. Note stomach with feeding tube in left
upper quadrant (LUQ). Scanogram shows distended bowel with haustra
oriented vertically at the epigastrium, and measuring > 9 cm in
diameter (Figure 3). Note stomach with feeding tube in LUQ. CT image
with IV contrast shows gaseous distended cecum anterior to collapsed
stomach containing a feeding tube (residual oral contrast after multiple
emesis) (Figure 4). A 1-cm diameter appendix interposed between the
malpositioned, distended cecum anteriorly and the displaced terminal
ileum posteriorly (Figure 5). The curvilinear course of superior
mesenteric vein (SMV) tributary veins is also noted. This image captures
the ascending colon coursing anteriorly to meet the air-filled cecum
(Figure 6). However, the classic bowel tapering (“beak”) at the point of
twist is not well seen. Note the characteristic, malpositioned, and
fluid-filled ileum to the right of the ascending colon. A CT coronal
reconstruction image (Figure 7) shows malpositioned, distended proximal
ascending colon and cecum anteriorly. A more posterior CT coronal
reconstruction image (Figure 8) shows the distended cecum superiorly as
well as the collapsed transverse colon inferiorly. The further posterior
CT coronal reconstruction image (Figure 9) shows the nasogastric (NG)
tube in the collapsed stomach. Moreover, a 11-mm diameter appendix is
seen curling toward the midline in the right upper quadrant (RUQ).
Discussion
This case is a rare presentation of two common entities. Although the worldwide incidence of acute appendicitis is 7% to 12%,
1 and
cecal volvulus causes 5% of large bowel obstructions, we found no
concurrent cases in English medical literature, and only 2 cases in
non-English literature.
2-4 The average age of patients at presentation with cecal volvulus is 53 years.4
Symptoms include colicky pain of sudden onset, vomiting, borborygmus,
and often dehydration with electrolyte disturbance. Leukocytosis may
also be present. Early diagnosis is essential to reduce the reported
high mortality rate. Volvulus is essentially a closed-loop obstruction
that may lead to vascular compromise with gangrene and perforation.
Cecal
volvulus occurs in patients with a mobile, defectively fixed right
colon, often while they are asleep. The volvulus occurs in the ascending
colon, above the ileocecal valve, and takes one of 2 forms. Axial
torsion, the more common form, is a twist of 180-360 degrees along the
longitudinal axis of the ascending colon. This form has a high mortality
rate, with immediate vascular occlusion occurring along with the
obstructive process. The second type (making up as much as 30% of
cases), illustrated by this case, is the bascule type, where the cecum
folds anteriorly and cephalad to the ascending colon, with the
production of a flap-valve occlusion at the site of flexion.
Defective
peritoneal fixation permitting abnormal mobility of the ascending colon
and cecum occurs in 10% to 25% of the population.2 Any sudden colonic distention may precipitate volvulus in these individuals.5
Associations include trauma, constipation, distal colonic obstruction
(ie, colonic carcinoma or diverticulitis), atony (colonic
ileus/pseudo-obstruction), colonoscopy, postpartum abdomen, and
postoperative abdomen. Traction due to a diseased appendix is also
implicated.2
In this case, colonic atony due to
appendicitis with traction of the diseased appendix seemed probable. At
surgery there was a non-ischemic, mobile ascending colon with the cecum
twisted around it in the epigastrium. The appendix was inflamed.
In
practice, differentiating between the 2 types of cecal volvulus is not
clinically important as their presentation and treatment are the same.
However, recognition of different radiographic appearances is important
for early diagnosis. Delay increases complications; these include 20%
mortality with perforation, and 45% mortality with gangrene. Distention
occurs in up to 65% of cases, with distention of more than 10 to 12 cm
placing patients at high risk for perforation. It has been suggested
that the duration of distention is as significant as the absolute size.2
In
diagnosis, bowel gas patterns may not be characteristic as the right
colon/cecum may be displaced to any part of the abdominal cavity.The
distended cecal loop may be confused with a sigmoid volvulus or even a
distended stomach. In fact, in one large review with abdominal
radiographs alone, cecal volvulus was suggested in 46% of patients, but
diagnostic in only 17%.4 If the positive diagnosis is not made on the abdominal series, follow-up films, contrast enema, or CT exam is required.
In
most patients, obstruction is almost complete; thus, the distal colon
is usually empty and the small bowel is frequently
distended.Occasionally, the folded, bascule-type volvulus may be
associated with signs of incomplete obstruction. The ileocecal valve may
be identified, and occasionally the point of torsion may be outlined by
intraluminal gas as an area of cone-like narrowing, or the so-called
“beak” sign.
In the cecal bascule form of volvulus, the distended,
air-filled cecum is located more centrally. The ileum may passively
twist with the cecum such that the small bowel is not obstructed. If the
appendix is gas filled and attached to a distended cecum in an unusual
location, the diagnosis can be made readily. In our case, care was taken
not to mistake the CT appearance of the inflamed appendix for a
displaced ileal loop.
On CT, the axial twist volvulus demonstrates
a U-shaped, distended bowel segment and signs of ischemia
(antimesenteric border),including mural thickening, infiltration of the
mesenteric fat, and pneumatosis intestinalis. A whirl sign may be
apparent with a tight torsiono of the mesentery caused by the twist
between the afferent and efferent loops.
Single-contrast barium
enema (BE) examination is used for the evaluation of cecal volvulus. As
little barium as possible should be allowed to flow proximal to the site
of obstruction as flooding proximal to the obstruction site might
precipitate complete obstruction. An attempt should be made to reduce
the volvulus. Reduction may be achieved during colonic filling by
barium, yet reduction occasionally occurs during barium evacuation.
In
the presence of a double obstruction of the colon (left colon
obstruction associated with a cecal volvulus), evaluation of the right
colon may not be possible with BE, and the diagnosis may need to be made
by plain radiographic findings or CT.
Definitive treatment is
surgical, particularly if reduction by barium enema fails. Colonoscopy
is unlikely to reduce the volvulus and risks colonic perforation.
Surgery is urgent when peritoneal tenderness or leukocytosis develops to
suggest ischemia. Cecopexy, cecostomy, and resection are all surgical
options. The highest rates of recurrence and complication are associated
with cecostomy. Cecal resection is favored in most patients due to
improvements in perioperative care and modern surgical techniques.
Ileocecectomy can be performed with low morbidity.4
Conclusion
Volvulus is not a rare condition. The various imaging appearances must
be recognized and considered immediately on plain film exams. High
morbidity can be reduced by early treatment. CT scans and barium enema
examinations are useful in diagnosis. Cecal resection is suggested
surgically.
- Khan AN, MacDonald S, Al-Khattab Y, et al. Cecal
volvulus. Medscape.
http://emedicine.medscape.com/article/364967-overview. Last Updated: May
25, 2011. Accessed July 21, 2011.
- Henisz AK, Silverman PM, Miller D; Reyelt P. Cecal volvulus. Applied Radiology. 2000;29: No. 11.
- D’Egidio A, Lipschitz J. Acute appendicitis associated with caecal volvulus. A report of 2 cases. S Afr J Surg. 1988;26:27-28.
- Bonis PAL, Hodin RA. Cecal volvulus. http://www.tuftsmedicalcenter.org/ForHealthCareProfessionals/GraduateMedicalEducation/InternalMedicineResidency/DeptofMedicine/default/2007DOMAnnualReport10-02-07BibOnly.pdf.Updated:
March 5, 2009. Accessed July 21, 2011.
- Gore RM, Levine MS. Textbook of gastrointestinal radiology, 2nd ed. Philadelphia, Pa: WB Saunders Co; 2000:704-725.