Brief Answer:
A few other possibilities listed

Detailed Answer:
Hello sir and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. In my opinion the most common and possibly causes for the hematoma you have been experiencing are the following:

+Accidental eye rubbing at night: This is one of the most common cause and can be avoided by using eye blinds
+Raise in blood pressure
+Medications: Like aspirin
+Vitamin K deficiency

Please discuss these causes with your doctor and I am sure you should be able to avoid the hematoma; your doctor may also consider a few other precautions so please do consider discussing these options with him/her.

Please also feel free to write back to me for any further clarifications, I am always here to help.

Best wishes.

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