Incision of the Internal Membrane Under an Endoscope for Advanced Organized Chronic Subdural Hematoma: A Case Report

Craniotomy with membranectomy is recommended for advanced organized chronic subdural hematomas (CSDH) that do not resolve with burr-hole irrigation and drainage. Nevertheless, the procedure remains controversial because of its potential complications, which include postoperative acute subdural hematomas and epileptic seizures. At present, for advanced organized CSDH, there is no clear consensus on whether complete membrane removal or incisions are the optimal management. We have obtained good results by performing a small craniotomy and making incisions in the thick, organized inner membrane with a sharp blade, without dissecting the inner membrane. Here, we report a case of organized CSDH that was successfully resolved by the same procedure performed with an endoscope through the burr-hole. An 81-year-old man was referred to our hospital with twice-recurrent CSDH after two burr-hole surgeries, accompanied by persistent left-sided motor weakness. A magnetic resonance imaging revealed an organized inner membrane, so an endoscopic incision of the inner membrane was performed through the previously opened burr-hole. After the clots in the hematoma cavity were cleanly removed, incisions were made randomly in the inner membrane using a sharp blade, with care not to damage the cortex, until pulsation of the brain tissue was observed endoscopically. A follow-up head computed tomography scan on the third postoperative day confirmed brain expansion. The patient recovered completely from the left-sided paralysis and was discharged home on the 20th postoperative day. In an advanced organized CSDH, the brain will not expand without treatment of the inner membrane, and CSDH will invariably recur. Detaching the hard inner membrane is not necessary, and once multiple incisions are made with a scalpel and the brain pulsation is confirmed, expansion can be expected after drainage of the hematoma cavity over multiple days. Several reports of successful treatment for organized CSDH have been reported, but absolute treatment has not yet been established. Incision of the inner membrane in endoscopic burr-hole surgery is a viable treatment option, with the need for large-scale pragmatic studies to prove safety and efficacy.