Brain with an air-pocket lesion in a rare case report of an elderly man

By Dr. Ananya Mandal, MDMar 15 2018

An 84 year old was complaining of repeatedly losing his balance and falling over. He visited his primary physician in Northern Ireland from where he was referred to the emergency room. On MRI, the team of doctors found a 3½-inch pocket of air in his brain. This has never been reported before in any case and thus the detailed report titled, “The man that lost (part of) his mind,” was published in the journal BMJ Case Reports.

The man was complaining of losing his balance and falling recurrently. Over the three days before he presented to the physicians, he was complaining of weakness of the left arm and leg. He had no other significant neurological problems with his vision, speech or hearing. There was no mental clouding or confusion or weakness of the facial muscles write the authors.

Dr. Finlay Brown, a leading author of the report and a general practitioner in Belfast was treating this man. Brown said they were suspecting some form of stroke because of the sudden appearance of the limb weakness and disturbance of balance. They then performed the scans of the brain expecting bleeding or brain damage that is caused due to stroke or blocked or bleeding brain arteries. They ended up finding a small benign tumour in the brain and an air pocket called a pneumatocele. This pocket of air was located at the patient’s right frontal lobe of the brain behind the frontal sinus and was situated above the cribriform plate the team writes. This cribriform plate is the plate that separates the cranial cavity (holding the brain) from the nasal cavity. It spanned over 3½ inches or 9 cm.

Brown said that the team was thinking along the lines of the air pocket being a residual damage from an earlier operation or an abnormality present since birth. But none of these were corroborated by the patient.

Presence of a pneumatocele is a very rare condition say experts and it is called pneumocephalus. The air pocket presses on the frontal lobe. This leads to problems with the workings of the voluntary muscles. In this case the team found a small benign or non-cancerous tumour within the paranasal sinus of the man. This osteoma or tumour was breaking through the walls of the cranium and this was what led to the air gathering in the brain matter from the sinuses. This gathered air from the leaking sinus had caused the air pocket believe the doctors. However the air that went in could not get out due to the non-return valve like opening of the leak.

The doctors treating the patient write that the air pressure from the air pocket was responsible for the stroke in the patient. This stroke caused the weakness of the limbs and problems with walking and maintaining balance.

After diagnosis the patient was offered to be treated surgically wherein the part of the bone and tumour would be removed and the leak would be closed. Decompression to ease the air pressure would be undertaken as part of the surgery too. The patient however declined to undergo the surgery due to his age and poor health. Conservative management to prevent stroke and manage its complications was opted for.

Source: http://casereports.bmj.com/content/2018/bcr-2017-222892.full?sid=dc43cb31-06f4-440b-8895-5087d9fe74ca