Introduction

The human brain is made up of irregular folds called gyri and grooves known as sulci. These irregularities increase the brain’s surface area, allowing it to accommodate more neurons without expanding in size. Imagine a brain with none of these structures—no folds, just a smooth surface? This condition is called lissencephaly, a rare neurodevelopmental disorder also known as “smooth brain.”
Lissencephaly is a congenital condition, meaning it is present at birth. It is primarily associated with genetic mutations. It has been found that non-genetic factors also contribute to the condition. This condition mostly has neurological symptoms such as developmental delay and seizures, but its damage extends beyond the nervous system.
One of the most missed complications in lissencephaly is the feeding difficulties and digestive complications.¹ These issues can significantly affect growth, development, and quality of life. This article explains the causes, symptoms, and management of feeding difficulties and gastrointestinal complications in babies with lissencephaly.

Neurological basis of feeding difficulties

The cerebral cortex is the part of the brain that has voluntary control over our muscles required for eating. The brain transmits neural signals to the muscles of the face and mouth, which aids in swallowing and also the coordination between eating and swallowing. Babies with lissencephaly have an underdeveloped brain cortex, which makes it difficult to control their muscles.² So, they require more time and effort to do things that others can do very easily. Another issue is the incoordination between eating and breathing. This causes choking and aspiration of food into the windpipe. Lissencephaly causes hypotonicity of muscles ,resulting in a  weak suckling reflex. Some may have increased muscle tone (Hypertonicity) in the musculature of the jaw and tongue, with deficient coordination of breathing and swallowing. Feeding in an upright position reduces the risk of choking.

Common feeding difficulties

Delayed feeding time due to weak sucking reflex makes it harder for the baby to concentrate. This may tire out the baby and the caretaker. The baby gets frustrated and may resist feeding, bottle, breast or spoon.³ They may also experience aspiration, causing choking, gagging, coughing and breathing obstruction in worst cases. The infant may even forget to swallow and keep the food in the mouth for a long time. Food may dribble or leak due to improper lip closure, which can be caused by a low tonicity of facial muscles. The babies refuse to eat and cry from hunger. This will be stressful for both the child and parent.⁴ The most challenging phase is the transition to solids. Just when the parent gets accustomed to the feeding practices, the baby reaches this milestone, making it very difficult for the parent to adapt. The hypertonicity of tongue muscles hinders chewing and swallowing. All of these can result in malnourishment as well as weight loss in babies. 

Gastrointestinal complications

Babies born with lissencephaly have a lot of digestive problems. They often deal with gastro-oesophageal reflux disease (GERD), which is common in kids with brain issues.⁵ It starts because their oesophagus loses its tonicity and delays stomach emptying. This leads to a lot of spit-up, vomiting, crankiness when eating, and arching of the back. As a result, the baby may experience food aversion and develop an inflamed oesophagus, also known as oesophagitis. Babies face a lot of risk during infancy due to this, as well as low muscle tone, slow movement of food in the intestines, and minimal feeding. The infant will frequently become dehydrated and have reduced bowel movement, resulting in constipation. Generally, the stomach takes longer to clear its contents, and the babies feel bloated or full.⁶ There's a huge overlap between feeding issues and their associated swallowing problems, and there’s a risk of aspiration pneumonia as a result of feeding problems. Breathing difficulties in some babies can present as silent, frequently overlooked conditions where food or water enters the lungs without being detected, often without coughing. Malnutrition and deficiencies of iron and calcium slow down growth and development.

Diagnostic approaches

The first step in diagnosis is clinical examination. Watch for symptoms such as choking, coughing, arching of the back, prolonged feeding durations, and weight loss. These suggest that the babies need medical attention. Feeding evaluations assess how the infant sucks, swallows, breathes, and manages various textures during feeding. A Videofluoroscopic Swallow Study (VFSS) is an essential test for swallowing assessment.⁷ It demonstrates the movement of food or liquid through the infant's mouth and throat in real-time via X-ray imaging. Another valuable assessment is the FEES (Fibreoptic Endoscopic Evaluation of Swallowing), which employs a small camera to directly visualise the swallowing process.  An upper GI contrast X-ray is used to assess the structure and function of the GI tract. Additionally, pH probe monitoring can measure acid levels in the oesophagus over a 24-hour timeframe, aiding in the diagnosis of gastroesophageal reflux. For nutritional evaluation, physicians may conduct blood tests to identify deficiencies in vitamins, iron, and calcium, while also monitoring anthropometric data such as weight, length, and head circumference.

Management strategies

Since this condition manifests in early human life, parents should be well aware of it. Always keep the child upright or lying on their side while feeding. This reduces the reflux and also prevents aspiration. Feed slowly and with care. Switching to semi-solid foods such as purees greatly helps in swallowing without risk of aspiration. High-calorie foods ensure the child gets enough nutrition. When mouth feeding is risky or impossible, G-tube or gastric feeding is administered as a last option. Medications such as proton pump inhibitors (PPIs) or H2 blockers help with reflux. Laxatives for constipation and stool softeners to help with bowel movements are also prescribed. In some cases, gut motility drugs like pyridostigmine might be used, but only under a doctor's watch. The treatment often requires a team, including a neurologist, gastroenterologist, nutritionist, speech and language therapist (SLT), and occupational therapist (OT).⁸ Working together and keeping up with check-ups are key to better feeding, good nutrition, and a better life overall.

Prognosis and quality of life

The feeding difficulties caused by lissencephaly not only affect the babies, but also take a toll on the mental health of the parents. Addressing the initial signs is crucial for early diagnosis and prompt management. This ensures that the baby is well-nourished and comfortable. It also reduces the risk of hospitalisation. Proper education and awareness among parents are essential for both the babies and the caretakers. Babies affected by this condition exhibit delayed milestones. Constant love and support, along with proper dealing, can make their lives so much better.

Conclusion

Lissencephaly, also known as "smooth brain," is a brain disorder that changes how the brain forms. This condition doesn't just affect the brain; it also makes it hard for babies to eat and digest food. Issues like reflux, hard stools, and food going into the lungs are common, but these can be handled with the right medical help. Prompt diagnosis, strategic management, and education for caregivers can significantly influence the physical and mental development of the affected babies.