Hydrocephalus is the growth and expansion of the chambers or ventricles in the brain tissue that are filled with cerebrospinal fluid, as a result of the increasing amount of this fluid. In normal healthy individuals, the cerebrospinal fluid is produced by specialized cells in these chambers and is reabsorbed after flowing through and around the chambers and the cortex of the brain and the spinal cord. Sometimes the fluid can accumulate in the ventricles and hydrocephalus may develop as a result of an increase in the production, decrease in the absorption of this fluid or due to congestion on the way to the area where it is absorbed.
Hydrocephalus may develop at any age. Hydrocephalus seen in adults has slightly different characteristics compared to childhood hydrocephalus. Adult hydrocephalus can usually develop after tumors and/or brain hemorrhages and traumas. Another specific type of hydrocephalus is normal pressure hydrocephalus which is seen in adults (also known as Hakeem-Adams syndrome).
Hydrocephalus After Tumor
This situation can be seen in tumors that compress the liquid flow spaces, especially those that compress or settle into the liquid cavities of the cerebrospinal fluid. In these cases, removal of the tumor is an effective method in the treatment of hydrocephalus because it will open up the liquid flow pathways. However, the content of certain specific tumors, such as vestibular schwannoma and epidermoid tumor, may cause hydrocephalus. In these cases, hydrocephalus may not be cured even if the tumor is surgically removed. In this case, a separate treatment for hydrocephalus may also be necessary.
Hydrocephalus After Bleeding
After the cerebrospinal fluid is released from the ventricles in the brain, it circulates around the brain and around the spinal cord and is absorbed from the small canaliculi. The cerebrospinal fluid is located between the brain and the arachnoid membrane, which is one of the membranes covering the brain. No matter where they come from in the brain, bleedings that occur into cerebrospinal fluid almost always get in the chamber where this fluid is located and gets mixed with the whole fluid matter circulating in the canals. After these subarachnoid hemorrhages (SAH), hydrocephalus develops because blood and blood products obstruct the pathways of fluid flow or blocks the canaliculi that ensure fluid absorption. The rate of hydrocephalus development is higher if this hemorrhage is related to a vein bubble (aneurysm). In rare cases where hemorrhage occurs into the brain tissue (parenchymal) due to blood pressure in middle-aged and elderly patients, blood may flow into the subarachnoid space or ventricles, resulting in hydrocephalus.
Normal Pressure Hydrocephalus (Hakeem Adams syndrome)
Although this type of hydrocephalus occurs usually in elderly patients, sometimes it can also occur in middle-aged and young patients. Characteristic symptoms of this disease include gait disorder (walking in short steps, impaired balance), forgetfulness (especially recent events), and urinary incontinence. The symptoms of this disease can often be confused with dementia. A lumbar puncture (fluid removal from the waist) is recommended for patients presenting normal pressure hydrocephalus symptoms in Brain Magnetic Resonance images to confirm the diagnosis. For patients whose complaints regress after lumbar puncture, diagnosis becomes clear and shunt surgery may be recommended for these patients.
Symptoms of hydrocephalus in adult patients
In middle-aged adults, balance disorder, urinary incontinence, dementia may be seen as well as headaches, difficulty in waking up or staying awake, personality disorders, and visual impairment. Elderly patients may experience imbalance while walking, difficulty in remembering, urinary incontinence, as well as impaired communication and headaches.
- Magnetic Resonance Imaging (MRI) is the gold standard. With these examinations, the brain’s own tissue can be evaluated in detail. In addition, the movement of cerebrospinal fluid in the brain tissue between cells and the flow of this fluid within and around the brain and the ventricle and channels can also be evaluated. In addition, pathologies such as tumors causing hydrocephalus can also be detected.
- Magnetic resonance imaging (MRI) methods that show the flow of cerebrospinal fluid: These examinations are especially used in situations that prevent the flow of cerebrospinal fluid. Although large tumors and other large-scale pathologies that obstruct fluid flow can be diagnosed by regular MRI, small sized tumors and in some cases narrownesses and obstructions in the way of fluid flow, that are congenital or acquired later, may not be seen in regular MRI. In such cases, MRI examinations that show cerebrospinal fluid flow may also be used.
- Computed Tomography (CT) is also frequently used in hydrocephalus, although it is better in showing the bone tissue. It also shows the hemorrhaging in patients who recently experienced hemorrhaging.
- Inserting a shunt: The purpose of shunt insertion is to transfer the accumulated excess fluid in the brain cavities to different spaces of the body. In this process, a catheter is inserted into the ventricles in the head, this catheter is connected with a pump, a second and longer catheter is connected to the other end of the pump, then this catheter is guided to the abdominal cavity under the skin and its tip is placed inside the abdomen. In this way, the excess fluid in the brain is transferred into the abdomen. The excess fluid is absorbed from the abdomen. Combining the catheters that lead to the brain and to the abdomen just above the skull, the pump allows the cerebrospinal fluid to flow in a controlled manner above a certain pressure value. Thus, the fluid accumulated in the brain is discharged to another part of the body. The abdominal cavity is often used to drain this fluid. The other end of the catheter that goes to the abdomen may also be connected to different parts of the body. In some cases, this fluid may be discharged into the chest cavity or into the heart with the help of a vein in the neck that leads to the heart. The shunt pumps that are used can have a fixed pressure setting or this pressure can be adjusted from the outside after insertion. The choice is made according to the clinical status of the patients. Patients with a shunt are closely monitored. Failure in shunt operation or infection may be encountered. Infection usually occurs in the first 6 weeks after surgery, but also may be observed later. Shunts with antibiotics may be used in patients with a recurrent shunt infection.
- Endoscopic third ventriculostomy: This treatment option may be used in case of the mechanical obstruction of the pathways that ensure fluid transfer. Not all patients with hydrocephalus may be suitable for this treatment. In this treatment option, to ensure fluid flow in the ventricles (fluid-filled spaces of the brain), a new hole is opened with an endoscope by accessing these spaces and the flow of accumulated fluid is ensured.