April 29, 2009

Japanese Guidelines for Treatment of Hepatocellular Carcinoma

Child-Pugh Score Online Calculator: Link

The algorithm is based on three factors
  1. Severity of liver damage (by Child-Pugh score)
  2. Number of tumors
  3. Diameter of tumors
Based on this algorithm:
  • Resection is considered if only one tumor of any size or two-to-three tumors of any size
  • Ablation is considered if 1) single tumor of less than 2 cm + Child-Pugh class 'B', 2) two-to-three tumors of equal or less than 3 cm.
  • Embolization is considered when 1) 4 or more tumors, 2) two-to-three tumors of > 3 cm
  • Interventional radiology Rx is considered in patients with class 'A' or 'B', not class 'C'
Reference:
Kokudo N, Makuuchi M. Evidence-based clinical practice guidelines for hepatocellular carcinoma in Japan: the J-HCC guidelines. J Gastroenterol 2009;44[Suppl XIX]:119-121.


April 26, 2009

Suspected Pulmonary Embolism in Pregnant Patient (2)


Potential algorithm for pulmonary embolism diagnosis in pregnant women (adapted from Pahade JK, et al. Radiographics 2009; 10.1148/rg.293085226)

First-Line Imaging Tests
Why Perform Chest Radiography?
  • Search for other causes of symptoms
  • Use to triage for further test, ie to perform lung scintigraphy or CT pulmonary angiography as the next test
  • Normal chest radiograph does not exclude PE
Why Perform Lower Extremity Ultrasound?
  • Positive result can be used to justified anticoagulation without further imaging
  • Negative result should warrant further imaging in the setting of clinically suspected PE because PE may occur in the absence of DVT, isolated pelvic DVT may occur without DVT in lower extremities
  • DVT is more common in the left lower extremity (more than right)
Reference:

Pahade JK, et al. Imaging pregnant patients with suspected pulmonary embolism: what the radiologist needs to know. Radiographics 2009; 10.1148/rg.293085226 (March 30, 2009)



April 24, 2009

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April 23, 2009

Jones Fracture


Jones Fracture
  • Fracture at proximal 5th metatarsal at metadiaphyseal junction (within 1.5 cm distal to tuberosity of 5th metatarsal)
  • Usually involve 4th-5th intermetatarsal joint
  • Sharp fracture margins without intramedullary sclerosis indicate acute fracture.
  • May present acutely or in a chronic phase
  • Acute Jones fracture has sharp margin without intramedullary sclerosis - usually Rx nonoperatively with NON weight baring cast
  • Persistent delayed union fracture will show fracture line in both cortices, callus, intramedullary sclerosis - usually Rx surgically
Reference:
Nunley JA. Fractures of the base of the fifth metatarsal the Jones fracture. Orthop Clin N Am 2001; 32:171-180.

April 20, 2009

Complications of Radiofrequency Ablation of Liver Tumors


Complications of RFA
  1. Vascular
  2. Biliary
  3. Extrahepatic

Major complication = those that if left untreated will threaten patient's life, causing substantial morbidity and disability, resulting in hospital admission or lengthen the hospital stay

Frequency of Complications
  • 4% per complete treatment or 1.9% per treatment session (Major)
  • 1.7% per complete treatment or 0.8% per treatment session (Minor)
  • In a series of 1000 patients with hepatocellular carcinoma, tumor seeding was the most common complication (1.5%), followed by liver abscess (0.7%), biloma (0.7%), portal vein thrombosis (0.4%) and bleeding requiring blood transfusion (0.4%).
Image Credit:
http://www.radiologyinfo.org/en/photocat/photos_more_pc.cfm?pg=rfa

Reference:
Akahane M, Koga H, Kato N, et al. Complications of percutaneous radiofrequency ablation for hepatocellular carcinoma: imaging spectrum and management. Radiographics 2005; 25:S57-S68.

April 17, 2009

Suspected Pulmonary Embolism in Pregnant Patient (1)


Figure: Transverse ultrasound image of the right femoral vein shows no evidence of deep vein thrombosis in a pregnant patient (7-week gestational age) presenting with acute dyspnea. Her subsequent CT pulmonary angiography shows multiple subsegmental pulmonary emboli.

Pulmonary Embolism in Pregnancy
  • One in 1,000 to 10,000 pregnancies in prenatal period
  • Risk of PE increases five fold during pregnancy
  • Risk of PE increases with successive trimester and puerperal period (some studies demonstrated equal risks among different trimesters)
  • Mortality up to 15-30%
  • PE is a preventable cause of maternal death
Clinical Problems
  • Difficult clinical diagnosis because of several conditions can mimic PE in pregnant patients, including normal physiologic change of pregnancy
  • D-dimer assay not helpful if positive
Imaging Diagnosis
  • No current standard guideline for imaging of PE in pregnant patients
  • Algorithm depends on institutional preference, resource availability and individual radiologist/physician practice pattern
  • Usual first-line imaging tests are chest radiography and lower extremity ultrasound
Reference:

Pahade JK, et al. Imaging pregnant patients with suspected pulmonary embolism: what the radiologist needs to know. Radiographics 2009; 10.1148/rg.293085226 (published online ahead of print on March 30, 2009)

April 11, 2009

Hangman's Fracture

Fig. 1: Lateral view of a cervical spine radiograph of an 18-year-old woman who sustained a motor vehicle accident shows anterolisthesis of C2 over C3 (arrowhead) and fracture lines involving the C2 pars interarticulares. The anterior and posterior spinal lines are disrupted.
Fig. 2: Axial CT image of the cervical spine at C2 level shows fractures of bilateral C2 pars interarticulares. The fracture on the right extends to the transverse foramen where the right vertebral artery is located. The examination also demonstrates an abrupt narrowing of the right vertebral artery, consistent with dissection.

Hangman's Fracture
  • Traumatic spondylolisthesis of C2
  • Fractures of the lamina, articular facets, pedicles or pars interarticulares of C2 with disruption of C2-C3 junction
  • Common etiology: fall, diving, motor vehicle collision
  • Treatment options depend on the stability of the fracture. Stable injuries without neurological deficit and signs of later instability - usually require only immobilization for a period of time.

Look for:
  • If there is anterior translation of C2 over C3, if translation >3 mm with >10 degree angulation -- likely unstable
  • If there is dislocation of facet joints -- likely unstable
  • Other associated C-spine pathology (found in up to 1/3 of cases)

Reference:
Li XF, Dai LY, Lu H, Chen XD. A systematic review of the management of hangman's fractures. Eur Spine J 2006;15:257-269.

April 8, 2009

Fulminant Candida Esophagitis

Fig: Double contrast barium esophagography shows innumerable pseudomembranes and plaques (arrows) "shaggy esophagus" in a patient with AIDS.

Candida Esophagitis
  • Most common cause of infectious esophagitis
  • Usually opportunistic infection in immunocompromised hosts, particularly AIDS
  • Can be seen in patients with esophageal stasis i.e. achalasia, scleroderma
  • Absence of oral thrush does not exclude this condition! (50% of patients with Candida esophagitis do not have thrush)
Radiographic Findings
  • Better with double-contrast barium esophagography (over single contrast)
  • Plaque (95% of cases) > abnormal motility = thickened folds = ulcers > "shaggy" contour
  • "When patients with esophageal symptoms are clinically immunosuppressed or have underlying obstructive disease of the esophagus, discrete plaque-like lesions should strongly suggest candidiasis on the double-contrast study"
Our case - fulminant Candida esophagitis.

References:
1. Levine MS, Macones AJ, Laufer I. Candida esophagitis: accuracy of radiographic diagnosis. Radiology 1985;154:581-587.
2. Levine MS, Rubesin SE. Diseases of the esophagus: diagnosis with esophagography. Radiology 2005;237:414-427.

April 5, 2009

Pelvic Congestion Syndrome

Fig. 1: Axial CT image of a 42-year-old woman with chronic pelvic pain shows dilatation of bilateral ovarian veins (arrows).
Fig. 2: Axial CT image of the same patient at the level of the uterus shows multiple dilated veins in the pelvic cavity, indicating pelvic varices.

Pelvic Congestion Syndrome
  • Multifactorial disease that may be from anatomical obstruction of ovarian veins, or secondary to other diseases such as valvular incompetence, portal hypertension.
  • Dilated, tortuous and congested veins with retrograde flow through ovarian veins
  • Signs and symptoms: deep, dull chronic pelvic pain, dyspareunia, dysmenorrhea, postcoital pain, varicose veins, tenderness on palpation
Imaging Findings
  • Not all pelvic varices represent pelvic congestion syndrome!
  • Dilated ovarian veins (normal 3-4 mm, borderline 4-8 mm, abnormal > 8 mm)
  • Reflux of contrast into ovarian vein(s)
  • Slow (3 cm/s) or reverse flow in ovarian veins
  • Polycystic changes of ovary
References:
1. Kuligowska E, et al. Pelvic pain: overlooked and underdiagnosed gynecologic conditions. Radiographics 2005;25:3-20.
2. Karaosmanoglu D, et al. MDCT of the ovarian vein: normal anatomy and pathology. AJR 2009;192:295-299.

April 2, 2009

FDG-PET: False Positive for Cancer

Fig. 1: Scout CT image shows a right hilar mass with right upper lobe opacity and volume loss. Findings are concerning for obstructive pneumonia due to carcinoma in the right hilum.
Fig. 2: Axial CT image shows right hilar lymphadenopathy (arrow) with consolidation, air bronchograms and cavities in the posterior segment of the right upper lobe (star)
Fig. 3: FDG-PET image shows markedly increased uptake of the right upper lobe consolidation, however the right hilar lymph node is not FDG avid.

False Positives FDG-PET in Lung Lesions
  • Infection: Pneumonia, mycobacterium avium complex infection, TB, fungal infection
  • Inflammation: Sarcoidosis, lipoid pneumonia, aspiration pneumonia, organizing pneumonia, amyloidosis, radiation pneumonitis
Why False Positive?
  • 18F-FDG is not specific for tumor.
  • Tissues with glucose uptake also takes FDG, especially tissues with metabolically active macrophages
  • High expression of gene such as GLUT-1 may also be a reason for high FDG uptake in inflammatory lesions

Our case - surgical resection shows organizing pneumonia in the right upper lobe.

Reference:
Gilman MD, Aquino SL. State-of-the-art FDG-PET imaging of lung cancer. Semin Roentgenol 2005;40:144.