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Explanation:
Extraosseous myelomatous masses are rare and found in less than 5% of patients with multiple myeloma. Although hepatic involvement in multiple myeloma has been described at autopsy in up to 30% of patients, clinical diagnosis is significantly less common. Diffuse and nodular patterns of plasma cell infiltration have been reported. Most often, focal liver lesions have been observed as non- or mildly enhancing on CT scan and as moderate or minimally enhancing on MRI
References:
– Patlas M, Khalili K, Dill-Macky MJ, Wilson SR. Spectrum of imaging findings in abdominal extraosseous myeloma. AJR Am J Roentgenol. 2004 Oct;183(4):929-32. doi: 10.2214/ajr.183.4.1830929. PMID: 15385283.
– Marcon M, Cereser L, Girometti R, Cataldi P, Volpetti S, Bazzocchi M. Liver involvement by multiple myeloma presenting as hypervascular focal lesions in a patient with chronic hepatitis B infection. BJR Case Rep. 2016 May 8;2(3):20150013. doi: 10.1259/bjrcr.20150013. PMID: 30459962; PMCID: PMC6243346.
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Explanation:
Lost appendicoliths (as well as gall stones) can cause delayed abscesses years after the surgical procedure. Due to a tilted position of the patient during surgery, the lost stones may “travel” towards the upper abdomen and can cause abscesses in the Morison pouch.
Therapy consists of surgical or interventional removal of the stone and drainage of the abscess.
References:
– Singh AK, Hahn PF, Gervais D, Vijayraghavan G, Mueller PR. Dropped appendicolith: CT findings and implications for management. AJR Am J Roentgenol. 2008 Mar;190(3):707-11. doi: 10.2214/AJR.07.2917. PMID: 18287442.
Diarrhea, postprandial dizziness and weakness
Weight loss of 20 kgs in the last 2 years
CT imaging was acquired
Mesenteric mass with calcifications surrounded by tethered small bowel loops
Retroperitoneal lymphadenopathy
Hypodense hepatic lesion, most likely metastasis
Mesenteric, retroperitoneal lymph node and hepatic metastasis of small bowel neuroendocrine tumor (NET)
Most commonly, this tumor originates in the terminal ileum, but in many cases, the submucosal primary lesion can’t be identified on CT
The mesenteric mass shows both calcifications and tethering of the surrounding bowels due to the characteristic desmoplastic reaction of the mesentery
For further work-up, the radiotracer Ga-68 DOTATATE is shown to be the most accurate at identifying NET
Diffuse abdominal pain
Worsened in the previous days, now unbearable
Previously had multiple surgeries in the abdomen (cholecystectomy, splenectomy after trauma, aorto-femoral bypass because of left AIC stent occlusion)
The emergency team did not have the impression that the cause might be bowel obstruction
Abdominal X-ray at that time was reported as normal
An ultrasound of the abdomen was requested
The diagnosis of small bowel obstruction (presumably because of post-operative adhesions) with at least one point of obstruction in the left lower quadrant was made
A CT scan was arranged for better anatomical delineation and to assess for complications
Closed loop small bowel obstruction, presumably because of adhesions after previous surgeries. Mesenteric edema indicates ischemia
No evidence to suggest that the cause of bowel obstruction would be a tumor, hernia or other etiology
SMA patent
No signs of perforation
The radiological diagnosis of small bowel obstruction is most commonly made with abdominal radiography
Occasionally, patients will present to the ultrasound department because of various justified and sometimes less justified reasons
The diagnosis of small bowel obstruction can be readily made on ultrasound, as demonstrated in this case. However, finding the cause and location of the point of obstruction is often difficult. The precise localisation of the point of obstruction, as seen in this case, is infrequently seen in real life practice
The CT scan excels compared to other modalities in finding the point of obstruction, the cause and associated complications in small bowel obstruction
It is almost always the next step in diagnostic management after positive abdominal X-ray or ultrasound findings
The most common complications of small bowel obstruction are bowel ischemia and perforation
A useful mnemonic for the cause of small bowel obstruction is ABC:
Adhesions – think of them after abdominal surgery
Bulge (i.e., hernias) – most commonly external like inguinal, femoral, and umbilical hernias (these are usually apparent clinically/can be seen with ultrasound), less commonly internal
C – Cancer or other tumors, which obstruct the bowel
If the point of obstruction is found, and a tumor is not differentiated and the point is not located in an external hernia, then it is presumed that the causes are adhesions (especially if the history mentions abdominal surgeries in the past)
A special type of bowel obstruction where the bowel is obstructed at two points in the immediate vicinity, thus forming a closed loop
The two points of obstruction compromise more easily; first, the venous and later the arterial blood flow to the closed loop of bowel
Associated with worse prognosis, as it leads more quickly to ischemia
A simple small bowel obstruction due to adhesions may be managed conservatively. A closed loop obstruction, however, is a surgical emergency
The CT signs in small bowel obstruction are:
Finding two points of obstruction in immediate vicinity (the collapsed bowel segments here are often hook-shaped and pointing to each other)
An odd C- or U-shaped configuration of bowel loops
Dilated bowel loops and mesenteric vessels converging to a central point
Mesenterial edema, bowel wall thickening and regional ascites indicate ischemia. A hyperdense bowel wall on non-contrast scan (due to intramural hemorrhage) and air in the bowel wall (pneumatosis intestinalis) are late signs of ischemia
For more information on this topic, I recommend the excellent closed loop obstruction articles and videos on radiologyassistant.nl
59-year-old female:
– Presented with weight loss (35 kg weight loss in 1 year)
– Diagnosed with celiac disease 2 years ago
– Laboratory findings: low levels of sodium, potassium, chloride, and calcium in the blood
Multiple mesenteric lymphadenopathies that contain fat-fluid levels (red arrows)
Splenic atrophy (red arrows)
Cavitating mesenteric lymph node syndrome
– Cavitating mesenteric lymph node syndrome is associated with celiac disease
– It is characterized by the triad:
(a) low attenuation lymphadenopathies that may contain fat-fluid levels
(b) splenic atrophy
(c) villous atrophy
– Cavitating mesenteric lymph node syndrome is associated with poor prognosis
– Many patients die of complications of cachexia and intestinal hemorrhage. Patients are prone to sepsis, often due to infections commonly associated with clinical hyposplenism, such as pneumococcal infection
– Treatment: Correction of electrolyte abnormalities, strict gluten-free diet, steroid therapy
– In our case, US-guided biopsy of one of the mesenteric lymphadenopathies was performed. Histopathologic examination showed acellular, chylous fluid. It was negative for malignancy or mycobacterial infection. The diagnosis of cavitating mesenteric lymph node syndrome was made in the clinical setting of celiac disease
73-year-old female patient:
* Abdominal pain
* Suspicion for ileus
Small bowel obstruction, with small bowel wall distension and transition point in the pelvis. At the point of transition there is a metal structure visible with the lumen of the bowel
No signs of bowel wall ischemia, no perforation
Acute small bowel obstruction due to migrated stomach tube plate
Requires surgery within 24 h
Possible complications: Perforation, abscess, ischemic changes
Treatment in this case: Laparotomy and surgical removal of the metal plate
2-year-old girl:
– Intermittent abdominal pain during the last 3 days
– Ultrasound exam of the abdomen was performed
Ileocolic intussusception
– Most common in small children (6 months–2 years)
– Proximal bowel (intussusceptum) invaginates into the distal bowel (intussuscipiens), most commonly ileocecal (90%)
– Classic triad of intermittent abdominal pain, vomiting and palpable right upper quadrant mass
– Red-currant jelly stool in late phase (signs of ischemia)
– Ultrasound is the imaging modality of choice
a) axial: alternating hyper- and hypoechoic concentric layers (target sign), sometimes with hyperechoic crescent-like mesentery (crescent in a doughnut sign)
b) longitudinal: pseudokidney sign (hilum = hyperechoic mesentery, cortex = hypoechoic bowel)
-US can identify lead points (e.g. lymph nodes, tumor, Meckel diverticulum), presence of trapped or free fluid
Imaging-guided reduction
– avoids surgery
– absolute contraindications: perforation, peritonitis, hemodynamic instability
– pneumatic or hydrostatic – increases the intraluminal pressure in the colon
– under fluoroscopic or ultrasound guidance (US better because of the lack of ionizing radiation)
Hydrostatic reduction under ultrasound guidance was performed
Fluid-distended cecum with gaping ileocecal valve and reflux of fluid in the terminal ileum as a marker of successful reduction
Pušnik L, Slak P, Nikšić S, Winant AJ, Lee EY, Plut D. Ultrasound-guided hydrostatic reduction of intussusception: comparison of success rates between subspecialized pediatric radiologists and non-pediatric radiologists or radiology residents. Eur J Pediatr. 2023 Jul;182(7):3257-3264. doi: 10.1007/s00431-023-04987-1. Epub 2023 May 6. PMID: 37148276; PMCID: PMC10354123.
78-year-old male:
-Presented with fatigue and weight loss
-Laboratory findings: low levels of total protein and albumin in the blood
– Periaortic soft tissue (red arrows)
– Bilateral pleural effusions (green arrows)
– Bilateral perirenal soft tissue thickening (blue arrows)
– Bilateral perirenal soft tissue thickening extending to the renal sinus, encasing the renal arteries and veins (blue arrows) There is mild dilatation of bilateral renal calyces from the retroperitoneal infiltration
– Soft tissue encasement of the descending aorta (red arrows)
– Left renal cyst (green arrow)
Erdheim-Chester disease
Teaching points
– Erdheim-Chester disease (ECD) is a non-Langerhans cell histiocytosis characterized by multiorgan xanthomatous infiltration
– The diagnosis is based on clinical, imaging, and histopathological features
– Patients with ECD may present with bone pain, diabetes insipidus, exophthalmos, constitutional symptoms, interstitial lung disease, ureteral obstruction, renal impairment, cardiac dysfunction and tamponade, cerebellar or pyramidal symptoms, and xanthelasma.
– ECD has a wide range of manifestations throughout the body
– Skeletal involvement is the most common. At imaging, there is bilateral patchy or diffuse symmetric osteosclerosis of the lower extremity metaphyses and diaphyses, with relative sparing of the subchondral surfaces. Radiographically, cortical thickening, coarsened trabeculae, medullary sclerosis, and loss of the corticomedullary differentiation may be demonstrated
– Kidneys and retroperitoneum are often involved
– CT and MRI may show ‘hairy kidney sign’ that is demonstrated as irregular symmetric infiltration of the bilateral perirenal and posterior pararenal spaces
– Obstructive uropathy may result from medial displacement of the ureters
– Periaortic soft tissue is often shown, which is known as ‘coated aorta sign’
– Pulmonary involvement has been reported in 15-35% of patients with ECD and includes smooth interlobular septal thickening, micronodules, ground-glass opacities, thickening of interlobar fissures, and parenchymal consolidation
– Chest radiographs will often show interstitial edema pattern with cardiomegaly and pleural effusions that do not respond to diuretics
– Orbital and central nervous system involvement are common findings. Retrobulbar masses that can cause proptosis and optic nerve edema may be present
– The hypothalamic-pituitary axis is the most common site affected within the central nervous system. Absence of the normal T1 hyperintense signal of the neurohypophysis occurs with enhancing nodular soft tissue of the pituitary stalk and posterior pituitary gland that results in central diabetes insipidus. Intra- and extra-axial cerebral and spinal lesions may be observed
– Treatment: Targeted therapy such as BRAF inhibitors, MEK inhibitors, interferon alfa, steroid therapy, radiotherapy, and surgery may be performed. There is no known cure for ECD and historically the prognosis has been poor
– In our case, a biopsy from the perirenal soft tissue was performed. The histopathological findings confirmed the diagnosis of ECD
