Hemispherotomy is a highly specialized neurosurgical procedure primarily performed on children and young adults suffering from severe epilepsy that originates from one hemisphere of the brain. It is often the last-resort treatment option when medications and less invasive therapies fail. While this surgery has the potential to significantly reduce or even eliminate seizures, understanding the symptoms after hemispherotomy is crucial for patients, caregivers, and healthcare providers.

A hemispherotomy is not a routine operation. It is typically reserved for patients with severe drug resistant epilepsy caused by conditions like Rasmussen’s encephalitis, hemimegalencephaly, Sturge Weber syndrome, or large cortical malformations. These are rare but debilitating disorders that severely impact a person’s ability to lead a normal life.

What Is Hemispherotomy?

Before diving into the symptoms, it’s important to understand the procedure itself. A hemispherotomy involves disconnecting one hemisphere of the brain (usually the side responsible for generating seizures) from the other. This is done without actually removing brain tissue. The goal is to isolate the dysfunctional hemisphere and stop seizure propagation.

This procedure is mainly performed for conditions such as Rasmussen’s encephalitis, hemimegalencephaly, Sturge Weber syndrome, and intractable epilepsy confined to one side of the brain. Though highly effective, hemispherotomy is a life-altering surgery that leads to both positive improvements and certain neurological symptoms post surgery.

Common Symptoms of Hemispherotomy

Every patient reacts differently to hemispherotomy. The symptoms post-surgery are largely determined by the age of the patient, the side of the brain operated upon, and pre existing neurological damage. Here are the most common symptoms associated with hemispherotomy :-

Hemiparesis or Hemiplegia :- One of the most expected symptoms after hemispherotomy is hemiparesis (partial weakness) or hemiplegia (complete paralysis) on the side of the body opposite to the disconnected brain hemisphere. This occurs because one hemisphere controls the motor functions of the opposite side of the body.

For example, if the left hemisphere is disconnected, weakness or paralysis may appear on the right side of the body. In many children, especially those who already had some motor deficits before surgery, this symptom doesn’t severely impact daily function. Intensive rehabilitation can significantly improve mobility and coordination over time.
Visual Field Loss :- Another frequently observed symptom after hemispherotomy is hemianopia, or loss of vision in half of the visual field in both eyes. This typically affects the side opposite the surgical hemisphere. So, a right-sided hemispherotomy may result in left visual field loss.

Although this condition may not be noticeable in very young children, it can affect older patients’ navigation and reading abilities. However, many patients learn to compensate for this loss through adaptation strategies and occupational therapy.
Temporary Speech and Language Difficulties :- Depending on the hemisphere involved, speech and language function may be affected after surgery. If the dominant (usually left) hemisphere is disconnected, patients may experience aphasia, which includes difficulties in speaking, understanding language, or forming sentences.

In children under the age of 5, however, the brain exhibits a remarkable plasticity, allowing the right hemisphere to gradually take over language functions. Speech therapy plays a vital role in helping patients recover and enhance communication skills post surgery.
Fatigue and Drowsiness :- Following surgery, most patients feel fatigued, drowsy, and require extended rest. This is a common response of the brain and body to major neurosurgery. It may last for a few weeks and gradually improve as the patient regains strength. Proper sleep, hydration, and nutrition support faster recovery.
Behavioral and Cognitive Changes :- Behavioral symptoms are not uncommon after hemispherotomy. Some children may become irritable, anxious, or emotionally sensitive. Cognitive changes can also occur, especially if the dominant hemisphere was involved. These changes may include :-
- Slower processing speed
- Difficulty in problem solving
- Short attention span
However, many of these challenges improve with time, especially with early intervention, cognitive therapies, and consistent support from caregivers and educators.

Positive Outcomes: Seizure Control and Cognitive Improvement

While the symptoms mentioned above may sound concerning, it’s important to emphasize the remarkable benefits of hemispherotomy, especially in cases of intractable epilepsy.

Studies show that up to 80-90% of patients experience significant reduction or complete cessation of seizures after the surgery. For children, this improvement often translates into better sleep, greater attention, improved behavior, and overall enhanced quality of life.

In many cases, the child was already suffering from severe seizures, developmental delay, or loss of function due to constant seizure activity. Stopping the seizures gives the remaining healthy hemisphere a chance to grow and rewire, offering unexpected developmental gains over time.

Long Term Symptoms and Adaptation

Long-term symptoms largely depend on pre-existing conditions and age at the time of surgery. Most children undergoing hemispherotomy are already coping with some degree of motor or cognitive disability due to their underlying neurological condition. Post-surgery symptoms may slightly intensify initially but often stabilize or improve within 6 months to a year.

With a combination of physical therapy, occupational therapy, speech therapy, and special education, many children achieve near normal developmental milestones.

Emotional Impact on Parents and Caregivers

Parents often experience mixed emotions post-surgery relief from seizures coupled with concern about new or intensified symptoms. Understanding the nature of hemispherotomy and setting realistic expectations with the help of a neurology team can ease emotional stress. Support groups and counseling services are also highly beneficial during the recovery phase.

When to Seek Medical Help?

While most symptoms after hemispherotomy are expected and manageable, certain signs require immediate medical attention :-

Persistent high fever
Uncontrolled vomiting
Severe or increasing headache
Swelling, redness, or discharge from the surgical site
New or different types of seizures
Sudden weakness worsening beyond the initial few days

Always follow your neurosurgeon’s guidance for post operative care and routine follow up imaging.

Conclusion

Hemispherotomy is a powerful surgical option for children and adults with severe, drug-resistant epilepsy localized to one hemisphere. While the surgery does come with some predictable symptoms like weakness, vision loss, or speech delay, the benefits especially in terms of seizure control and developmental recovery often outweigh these challenges.