What Causes Hypodensity in Liver? Comprehensive Guide

What causes hypodensity in liver doesn't have a single answer. Liver hypodensity refers to areas in computed tomography (CT) scans that appear darker than the surrounding liver tissue, These findings may suggest a range of conditions from extremely harmless (benign) to serious conditions (e.g., cancer or infection). Timely and proper diagnosis is important to know which action to take after. Most liver hypodensities are discovered incidentally (discovered by accident), which are benign and require no treatment.

Key Takeaways

• What causes hypodensity in liver is mostly benign and incidentally found during CT scans

• Hypodensities found don’t require treatment

• Common benign lesions (abnormal area of tissue) include cysts, hemangiomas, and local (focal) fatty changes

• Malignant causes are less common, such as metastases and primary liver cancers, but would require prompt management

• Symptoms like upper right abdominal pain, jaundice, and unexplained weight loss require medical investigation

• The risk factors include cirrhosis, chronic hepatitis, obesity, and alcohol abuse

What is Hypodensity in the Liver?

Hypodensity in the liver shows up as areas that look darker than the rest of the liver tissue on CT. These focal areas can mean a lot of things — some less serious and common and others requiring further investigation. Hypodensities look like shadows within the liver tissue, which has their own significance about liver health.

What does hypodensity mean in medical terms?

Medically speaking, hypodensity means areas that don’t take up as much X-rays during the scan. Hence, these spots would look darker on the resulting images than the normal liver tissue. Doctors interpret these areas in varying ways to figure out what is going on in your liver. It can signify to be the first clue that something needs further investigation.

How is hypodensity detected in the liver?

CT scans are the primary way that doctors find hypodensities in the liver. Often, they use an approach called “portal venous phase” (a method that uses dye as contrast) to identify lesions that don’t have many blood vessels. 

If doctors want more details, magnetic resonance imaging (MRI) is another method as necessary.

But ultrasound is primarily the first approach to check first (incidental or not) or to monitor the status of the lesion over time.

These imaging techniques are tools that can work singly or in combination to determine what causes hypodensity in liver.

Common Causes of Liver Hypodensity

Hypodensities in the liver can stem from things that are not cancerous (benign) or from malignant (cancerous) issues. Hepatic cysts, for instance, show up in about 1-14% of autopsies (after death examination of the body). Cancer that spreads to the liver from elsewhere in the body (metastasis) is more common at nearly 97% in patients without cirrhosis (scarring of the liver tissue) than those with cirrhosis (63.2%). So, getting the correct diagnosis matters to know what your treatment plan is.

What are benign causes of liver hypodensity?

Things that cause liver hypodensity are mostly not dangerous or cancerous. It may be caused by things like:

• Hepatic (liver) cysts that are fluid-filled sacs, which are mostly not a cause of concern (depending on what caused its growth in the first place)

• Bile duct hamartomas are tiny growths that form when bile ducts develop abnormally

• Focal steatosis (localized fatty buildup) is a condition where fat accumulates in local areas of the liver

• Hemangiomas are clumps of blood vessels, which are quite common, existing at about 0.4-20% of the general population.

• Adenomas are non-cancerous growths that occur mostly in women who are taking birth control pills

Most of these causes don’t need management or treatment. Exceptions of which are those that cause pain or are particularly problematic.

What are malignant causes of liver hypodensity?

Primary cancer of the liver is uncommon with only 63.2% incidence as mentioned previously. Hepatocellular carcinoma (HCC) is the most common primary liver cancer (cancer that starts in the liver). About 90% of HCCs are associated with a known cause including:

• Chronic viral hepatitis

• Long-term alcohol abuse

• Non-alcoholic fatty liver disease

Cholangiocarcinoma is another type of cancer that starts in the bile ducts and later affects the liver.

Common cancer that spreads to the liver from elsewhere include colon, lung, or breast cancer.

Early detection of these growths can make a significant difference when it comes to treatment and intervention.

Can infections cause liver hypodensity?

Yes, infections can cause focal hypodensities (darker spots) on liver scans, among other reasons. Liver abscesses are spots of pus resulting from bacterial infections, needing antibiotics and sometimes drainage. Parasitic infection, such as from echinococcus, form cysts in the liver that also appear hypodense on scans as well.

Benign vs. Malignant Liver Lesions

Cancerous and non-cancerous spots in the liver would look different on scans. But for the inexperienced and without medical background, these may look the same.

How can you tell if a liver lesion is benign or malignant?

For trained professionals, non-cancerous lesions usually have smooth edges and don’t grow beyond their localized regions. If they do grow, it is slow but the majority remains stable over the years. Each type of benign lesions (depending on the exact cause) has their own way of taking up contrast dyes. For example, hemangiomas take up the dye from outside in. Most importantly, these lesions don’t spread to other parts of the body.

For cancerous lesions, they often grow fast, beyond their point of origin, and have rough edges. These lesions can take up contrast dyes during scans in odd patterns. They grow fast and some parts of the lesion die off (become necrotic). They can grow into nearby blood vessels as well.

But to confirm if the lesion is cancerous or benign does not solely depend on their appearance on scans like CT or magnetic resonance imaging (MRI). The confirmatory test is always a biopsy (getting a sample from the lesion and sending it to the laboratory for reading).

The impact on your health is also significantly different. Benign lesions are rarely a cause of concern while malignant ones need immediate and prompt medical attention.

How is Hypodensity Diagnosed?

What imaging tests are used to diagnose liver hypodensity?

The main tool used to diagnose liver hypodensity is CT scan. It shows the size, location, and basic features of the lesion. If contrast is used, the liver is viewed in various phases as the dye moves through it. It is then viewed in the arterial phase, the portal venous phase, and the delayed phase.

MRI doesn’t use hypodensity but instead uses the word hypointensity. The meaning is basically the same, just different for varying imaging techniques. It gives more detail about the insides of the lesions and how they relate to the surrounding tissues.

The term for hypodensity in ultrasound is “hypoechoic” or decreased echogenicity. Ultrasound is best for screening and monitoring the lesions over time since it costs less than the two previously mentioned imaging.

In PET (positron emission tomography), the term used to describe these lesions is “increased or decreased uptake.”

Each of these imaging modalities have their own strengths. Often doctors use more than one if the diagnosis remains inconclusive.

What role does a biopsy play in diagnosis?

When imaging results don’t point out a specific pathology, doctors often resort to a more invasive approach, which is biopsy. This test, as mentioned, is confirmatory. This involves getting a sample from the liver lesion (usually imaging guided). The sample goes to the laboratory where experts examine it under a microscope.

Biopsies are necessary to determine the specific cause of the lesion. It is particularly done when scans show something concerning the lesion — be it malignant or benign. Knowing exactly what it is will make a difference in planning out a management and treatment plan.

Are there blood tests that can help diagnose liver hypodensity?

Generally, blood tests are not directly used to diagnose liver hypodensity. But they give helpful clues that will aid in the diagnosis.

• Liver function tests allow you to know whether your liver is working properly (as it should be)

• Tumor markers like AFP may help diagnose certain cancers

• Hepatitis panels can find infections that increases your risk for liver issues like cirrhosis

While not diagnostic, these tests support the images that scans show. However, these tests cannot replace diagnostic imaging.

Symptoms and When to See a Doctor

Many liver lesions that cause hypodensity are found by chance. They don’t usually cause problems depending on what type they are. But there are certain lesions that may cause symptoms. Learn what they are so you know when to see a doctor.

What symptoms might indicate a problem with the liver?

There are symptoms that may suggest problems with the liver. But even when they are present don’t necessarily mean you have it. The following are non-specific symptoms (in terms of cause whether malignant or benign):

• Right upper abdomen pain or discomfort

• Bloating or always feeling full

• Nausea and vomiting

• Loss of appetite or unintentional weight loss

• Fatigue and feeling weak

Not all liver lesions or problems will manifest these signs. In fact, some people with serious liver disease feel fine for a very long time. 

When should you seek medical attention for liver issues?

There are also serious symptoms that you should not ignore. Rather, it should prompt immediate medical attention. These symptoms include:

• Severe abdominal pain or pain that doesn’t go away even with pain medications

• Sudden onset of jaundice (yellowish discoloration of the skin and eyes)

• Confusion or disorientation (or other signs of altered mental status)

• Signs of internal bleeding (hemorrhage) specifically if you have been diagnosed with large simple cysts that ruptured

• Fever with severe fatigue or weakness (this could indicate infection)

• Sudden palpable mass under the right ribs

If you have any of these symptoms, you need urgent medical care and evaluation. It may reflect serious complications of your liver lesion. Prompt treatment or hospitalization may be required in these cases. Early intervention often leads to better outcomes.

Are there any risk factors for developing liver hypodensity?

Yes, there are risk factors that can increase your chances of developing liver hypodensity.

• Chronic (long-term) hepatitis infection with B or C can cause damage over time

• Cirrhosis (liver scarring) from any cause

• Heavy alcohol drinking

• Overweight or obesity

• Diabetes

• Exposure to poison or toxins

Knowing if you have these risks is important for you to take precaution or stay vigilant about your liver health.

Treatment Options for Liver Hypodensity

Treatment options depend on the exact cause of liver hypodensity. Benign lesions need to be monitored every now and then. On the other hand, cancer lesions are more aggressive. So more aggressive management is necessary. Treatment option also depends on how big the lesions are and if they have spread.

Do all cases of liver hypodensity require treatment?

No, not all liver hypodensities require treatment. Like mentioned, most benign hypodensities only require occasional or periodic monitoring. Cancerous liver hypodensities need a treatment plan right away.

Your doctor will know what to do as soon as the exact cause of the hypodensity is known. It also depends on the size and your overall health.

What Treatments Are Available for Liver Hypodensities?

If what you have is benign liver hypodensity, doctors often recommend watchful waiting. That is, you just keep an eye on them with occasional or periodic scans. However, this also depends on the size. If the lesions are large and cause pain, surgery may help. Treatment options include:

• Ablation (burning the lesion)

• Cutting off their blood supply (embolization)

Fortunately, most benign liver hypodensities don’t grow or cause trouble over time.

On the other hand, cancerous lesions may be treated with the following:

• Surgical resection

• Liver transplant

• Ablation

• Chemotherapy

• Targeted therapy

• Immunotherapy

• Radiation

Often the treatment for cancerous growth is multiple or more than one approach.

Conclusion

Most liver lesions that show up on CT scans are benign. Hepatic cysts at 5.8% and hemangiomas at 3.3% of cases are the most common findings. Hemangiomas is the most common benign tumor in the liver, which appears as sharply defined hypodense lesions. Knowing exactly what causes hypodensity in the liver allows you to stay informed about your liver health. It will also guide you on what to do next or whether it should cause worry.

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Frequently Asked Questions

What exactly does "hypodensity" mean when doctors talk about my liver scan?

The term hypodensity means areas that appear darker on CT scans. These are areas that absorb less X-ray radiation compared to the surrounding liver tissue.

Can liver hypodensity go away on its own?

No. Liver hypodensities do not go away on their own. Even when the cause is benign, they don’t resolve without treatment like infection or inflammation. However, this does not mean that they need to be treated right away. 

Should I be worried if my doctor found a hypodense lesion in my liver?

Not entirely. Most hypodense liver lesions are only accidentally found and asymptomatic at the time of discovery. It still depends on the exact cause whether you should be worried or not.

Can diet or lifestyle changes help with liver hypodensity?

Diet and lifestyle changes won’t make liver hypodensities go away. But they can improve liver function and may help in conditions like fatty liver disease. They can also improve the outcome of treatment in some cases.

Written by Jaclyn P. Leyson-Azuela, RMT, MD, MPH
Jaclyn P. Leyson-Azuela, RMT, MD, MPH, is a licensed General Practitioner and Public Health Expert. She currently serves as a physician in private practice, combining clinical care with her passion for preventive health and community wellness.

References

Azizaddini, S., & Mani, N. (2021). Liver Imaging. PubMed; StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK557460/ 

Baba, Y. (2023, March 23). Portal venous phase | Radiology Reference Article | Radiopaedia.org. Radiopaedia. https://radiopaedia.org/articles/portal-venous-phase 

Cleveland Clinic. (2023, October 4). Liver Disease: Types. Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/17179-liver-disease

Galvão, B. V. T., Torres, L. R., Cardia, P. P., Nunes, T. F., Salvadori, P. S., & D’Ippolito, G. (2013). Prevalence of simple liver cysts and hemangiomas in cirrhotic and non-cirrhotic patients submitted to magnetic resonance imaging. Radiologia Brasileira, 46(4), 203–208. https://doi.org/10.1590/s0100-39842013000400005 

Ghenciu, L. A., Mirela Loredana Grigoras, Rosu, L. M., Sorin Lucian Bolintineanu, Sima, L., & Cretu, O. (2025). Differentiating Liver Metastases from Primary Liver Cancer: A Retrospective Study of Imaging and Pathological Features in Patients with Histopathological Confirmation. Biomedicines, 13(1), 164–164. https://doi.org/10.3390/biomedicines13010164 

Hepatocellular Carcinoma - Hepatic and Biliary Disorders. (n.d.). MSD Manual Professional Edition. https://www.msdmanuals.com/professional/hepatic-and-biliary-disorders/liver-masses-and-granulomas/hepatocellular-carcinoma 

Joo Hyun Oh, & Dae Won Jun. (2023). The latest global burden of liver cancer: A past and present threat. Clinical and Molecular Hepatology, 29(2), 355–357. https://doi.org/10.3350/cmh.2023.0070 

Kaltenbach, T. E.-M., Engler, P., Kratzer, W., Oeztuerk, S., Seufferlein, T., Haenle, M. M., & Graeter, T. (2016). Prevalence of benign focal liver lesions: ultrasound investigation of 45,319 hospital patients. Abdominal Radiology, 41, 25–32. https://doi.org/10.1007/s00261-015-0605-7 

N Bajenaru, Balaban, V., F Săvulescu, I Campeanu, & T Patrascu. (2015). Hepatic hemangioma -review-. Journal of Medicine and Life, 8(Spec Issue), 4. https://pmc.ncbi.nlm.nih.gov/articles/PMC4564031/ 

Radiological Descriptive Terms. (n.d.). Radiology at St. Vincent’s University Hospital. http://www.svuhradiology.ie/diagnostic-imaging/radiological-descriptive-terms/ 

Salam, H. M. A. (n.d.). Focal hypodense hepatic lesions on non-enhanced CT (differential) | Radiology Reference Article | Radiopaedia.org. Radiopaedia. https://radiopaedia.org/articles/focal-hypodense-hepatic-lesions-on-non-enhanced-ct-differential 

The Radiology Assistant : Common Liver Tumors. (n.d.). Radiologyassistant.nl. https://radiologyassistant.nl/abdomen/liver/common-liver-tumors 

What Are Liver Lesions? (n.d.). WebMD. https://www.webmd.com/hepatitis/liver-lesions