Skillnader

Här visas skillnader mellan den valda versionen och den nuvarande versionen av sidan.

--- leversteatos [2026/01/13 09:03] – [Differential diagnosis] akestorck
+++ leversteatos [2026/01/13 09:28] (aktuell) – akestorck
@@ Rad 1: / Rad 1: @@
 ====== Liver steatosis ======
-**Hepatic steatosis**, also known as **fatty liver disease**, refers to abnormal accumulation of fat within hepatocytes, most commonly manifesting as **non-alcoholic fatty liver disease (NAFLD)**. It represents a spectrum from simple steatosis to steatohepatitis and cirrhosis, frequently identified incidentally on imaging.
+**Hepatic steatosis**, also known as **fatty liver disease**, refers to abnormal accumulation of fat within hepatocytes, most commonly manifesting as **non-alcoholic fatty liver disease (NAFLD)**.
 ===== Epidemiology =====
-Hepatic steatosis affects up to 30% of the general population in Western countries, with rising prevalence linked to obesity, diabetes, and metabolic syndrome. Prevalence exceeds 70% in patients with type 2 diabetes and reaches 90% in those undergoing bariatric surgery. Risk factors include insulin resistance, hyperlipidemia, rapid weight loss, total parenteral nutrition, and certain medications.
+Hepatic steatosis affects up to 30% of the general population in Western countries, with rising prevalence linked to obesity, diabetes, and metabolic syndrome. Prevalence exceeds 70% in patients with type 2 diabetes and reaches 90% in those undergoing bariatric surgery.
 ===== Clinical presentation =====
-Most cases remain asymptomatic and are detected incidentally on ultrasound or other imaging. Symptomatic patients may report right upper quadrant discomfort, fatigue, or elevated liver enzymes. Advanced disease can progress to non-alcoholic steatohepatitis (NASH), fibrosis, cirrhosis, or hepatocellular carcinoma.
+Most cases remain asymptomatic and are detected incidentally on ultrasound or other imaging. Symptomatic patients may report right upper quadrant discomfort, fatigue, or elevated liver enzymes.
 ===== Pathology =====
-Steatosis results from impaired fat metabolism, with triglycerides accumulating in >5% of hepatocytes. Macrovesicular steatosis predominates, featuring a single large cytoplasmic fat droplet displacing the nucleus; microvesicular involves multiple small droplets. Focal forms occur due to variant venous drainage, while diffuse patterns predominate.
+Steatosis results from impaired fat metabolism, with triglycerides accumulating in >5% of hepatocytes. Macrovesicular steatosis predominates, featuring a single large cytoplasmic fat droplet displacing the nucleus.
 ===== Radiographic features =====
 ==== Ultrasonography ====
-* **Hyperechoic liver parenchyma** ("bright liver") compared to kidney or spleen
-* Grading:
+  * **Hyperechoic liver parenchyma** ("bright liver") compared to kidney or spleen
-^ Grade ^ Features ^
+  * **Grading**:
-| Mild  | Slight echogenicity increase |
-| Moderate | Impaired vessel wall visualization |
+^ Grade     ^ Features                                      ^
-| Severe | Poor diaphragm/portal vein visibility |
+| Mild      | Slight echogenicity increase                   |
+| Moderate  | Impaired vessel wall visualization             |
+| Severe    | Poor diaphragm/portal vein visibility          |
 ==== Computed tomography ====
-* **Unenhanced CT**: Liver attenuation <40 HU absolute or >10 HU lower than spleen
-* **Contrast-enhanced**: Focal sparing appears hyperdense relative to steatotic parenchyma (gallbladder fossa, segment IV)
+  * **Unenhanced CT**: Liver attenuation <40 HU absolute or >10 HU lower than spleen
-* Dual-energy CT improves quantification.
+  * **Contrast-enhanced**: Focal sparing appears hyperdense relative to steatotic parenchyma (gallbladder fossa, segment IV)
+  * Dual-energy CT improves quantification
 ==== Magnetic resonance imaging ====
-* **Chemical shift imaging** (in/out-of-phase): Signal dropout on opposed-phase images (>5% fat)
-* **Proton density fat fraction (PDFF)**: Gold standard for quantification (linear, reproducible)
+  * **Chemical shift imaging** (in/out-of-phase): Signal dropout on opposed-phase images (>5% fat)
-* **Spectroscopy**: Measures fat fraction directly.
+  * **Proton density fat fraction (PDFF)**: Gold standard for quantification
+  * **Spectroscopy**: Measures fat fraction directly
 ===== Treatment and prognosis =====
@@ Rad 36: / Rad 40: @@
 ===== Differential diagnosis =====
-* Glycogen storage disease (US: hyperechoic but vessels clear)
-* Acute hepatitis (diffuse hypoechoic)
+  * Glycogen storage disease (US: hyperechoic but vessels clear)
-* Focal fat sparing/deposition mimics mass
+  * Acute hepatitis (diffuse hypoechoic)
-* Iron overload (high attenuation on CT)
+  * Focal fat sparing/deposition mimics mass
+  * Iron overload (high attenuation on CT)
+===== References =====
+* [[https://pubs.rsna.org/doi/full/10.1148/rg.266065004|RadioGraphics 2006: Fatty Liver]]
+* [[https://pmc.ncbi.nlm.nih.gov/articles/PMC6824276/|Ultrasound Med 2019]]
+* [[https://ajronline.org/doi/10.2214/AJR.11.7838|AJR Am J Roentgenol 2012]]
+* [[https://pubs.rsna.org/doi/full/10.1148/radiol.2021204288|Radiology 2021]]
+* [[https://pmc.ncbi.nlm.nih.gov/articles/PMC4064084/|World J Gastroenterol 2014]]
+* [[https://www.sciencedirect.com/science/article/abs/pii/S0720048X06004451|Eur J Radiol 2007]]
 > **Medical Disclaimer**: Portions of this content were AI-generated to facilitate rapid knowledge synthesis. Radiologists and clinicians must independently verify all information against peer-reviewed literature, institutional protocols, and patient-specific factors before clinical application.