Question:  A 74 year old male undergoes total auriculectomy, lateral temporal bone resection, and parotidectomy for an auricular squamous cell carcinoma.  Reconstruction is performed using an anterolateral thigh fasciocutaneous free flap.  Serial examination reveals progressive venous congestion that does not improve with aspirin and heparin administration.  A decision is made to use medicinal leeches.  After a therapy session, a leech is removed and persistent bleeding is noted from the site.  What is the mechanism of the ongoing bleeding?  [Answer will be posted with next week's new question]

Answer to last week's question, "Triangulating..." (June 13, 2016): 

The posterior border of the mylohyoid muscle, digastric tendon sling, and hypoglossal nerve form the boundaries of Lesser's triangle.