The Macrocephaly Is a neurological disorder in which there is an abnormal increase in head size (National Institute of Neurological Disorders and Stroke, 2015).
Specifically, there is an increase in the cranial perimeter, that is, the distance around the widest or upper area of the skull is greater than Expected for the age and sex of the affected person (National Institutes of Health, 2015).
At a more clinical level, macrocephaly occurs when the perimeter or cranial circumference is above the average of that age and sex in 2 Standard deviations or is greater than the 98th percentile (Erickson Gabbey, 2014).
These signs may be evident from birth or develop in the early years of life (National Institute of Neurological Disorders and Stroke, 2015).
In general, it is a rare disorder that affects men more frequently than women (National Institute of Neurological Disorders and Stroke, 2015).
Although not all cases of macrocephaly are cause for alarm, it is often accompanied by various symptoms or medical signs: generalized delay Of development, seizures, corticospinal dysfunctions, among others (National Institute of Neurological Disorders and Stroke, 2015).
Characteristics of macrocephaly
The Macrocephaly Is a neurological disorder that falls within the Cranial growth disorders .
In pathologies or disorders of cranial growth anomalies occur in cranial size due to different alterations in the bones of the Cranial vault or in the Central Nervous System (Martí Herrero and Cabrera López, 2008).
Specifically, macrocephaly is defined as an anomalous increase in the cranial perimeter that is above the expected value for age and sex Of the person affected (García Peñas and Romero Andújar, 2007).
This type of alterations may be due to an excess of volume of cerebrospinal fluid , An increase in the size of the brain or even a
Thickening of the cranial vault (García Peñas and Romero Andújar, 2007).
Although a large number of macrocephalic sufferers do not present significant signs or symptoms derived from the pathology, many others Have significant neurological abnormalities.
About us
There are no specific statistical data on the prevalence of marocephaly in the general population.
However, the clinical studies consider that it is a rare or rare disease, which occurs in approximately 5% of the population
(Mallea Escobar et al., 2014).
It is usually a disorder that affects the male sex in greater proportion and is usually present at birth or develops in the first
Years of life, therefore infant macrocephaly is common.
Symptoms and signs
Derived from the definition of this pathology, the most characteristic symptom of macrocephaly is the Presence of an abnormally large head size.
As in the case of other pathologies or disorders affecting cranial growth, head size is measured through the circumference or Cranial perimeter, the measurement of the contour of the head at the top (Microcephaly, 2016).
The size of the head or skull is determined either by brain growth, cerebrospinal fluid (CSF) volume or blood, or by The bone thickness of the skull (Mallea Escobar et al., 2014).
A variation in some of these factors may cause important neurological consequences, therefore it is crucial that a control and Measurement of cranial perimeter growth in newborns and children, especially during the first years of life (Mallea Escobar et al. Al., 2014).
The standard growth patterns show the following values (Mallea Escobar et al., 2014):
- Cranial perimeter in term newborns : 35-36cm.
- Approximate growth of the cranial perimeter during the first year of life : Approximately 12cm, more pronounced in males.
- Rate of increase of the cranial perimeter during the first three months of life : Approximately 2cm per month.
- Rate of increase of the cranial perimeter during the second trimester of life : Approximately 1cm per month.
- Speed of increase of the cranial perimeter during the third and fourth quarter of life : About 0.5cm per month.
The values obtained from head size measurement in medical and health checks should be compared to a Standard or expected growth. Children with macrocephaly present values significantly higher than the mean of their age and sex.
Due to the different etiologies that will lead to increased head size, different medical complications may appear Affect both the neurological functioning and the general functional level of the affected.
Complications or possible consequences
The medical conditions associated with macrocephaly will depend on the etiologic cause, despite this, there are some clinical manifestations Frequent (Martí Herrero and Cabrera López, 2008):
- Asymptomatic macrocephaly.
- Convulsive episodes.
- Generalized delay in development, cognitive and intellectual deficits, hemiparesis, etc.
- Vomiting, nausea, headache, drowsiness, irritability, lack of appetite.
- Alterations and deficits of gait, visual deficits.
- Signs of endocranial hypertension, anemia, biochemical alterations, systemic bone pathologies.
Causes
As we pointed out earlier, macrocephaly may appear due to different alterations affecting the Brain size, cerebrospinal fluid volume or due to bone abnormalities.
One of the publications of the Spanish Association of Pediatrics Microcephaly, makes a detailed classification of Causes of macrocephaly (Martí Herrero and Cabrera López, 2008):
Cerebral and cerebrospinal fluid (CSF) pathology
In the case of macrocephaly due to the presence or development of a cerebral pathology and / or cerebrospinal fluid, Macrocephaly of primary or secondary origin .
to) Primary macrocephaly
Primary microcephaly occurs as a consequence of an increase in brain size and weight.
Generally, in this type of microcephaly can be observed a greater number of nerve cells or a greater size. When determining the presence of This etiological cause, the pathology is renamed Macroencephaly.
This type of alterations usually have a genetic origin and therefore, are part of this classification the Family macrocephaly and the Hemimegalencephaly.
In addition, it is common for macroencephaly to form the set of clinical manifestations of other pathologies such as: bone dysplasias, fragile X, Sotos syndrome, Beckwith syndrome, chromosomopathies, etc.
B) Secondary microcephaly
Secondary microcephaly, or Progressive or evolutionary microcephaly May be due to changes in the volume of Cerebrospinal fluid, and the presence of occupant lesions or substances.
- Increased level and volume of cerebrospinal fluid (CSF) : Anomalies in the production, drainage or reabsorption of fluid Cerebrospinal fluid may cause an accumulation of the latter and therefore lead to Hydrocephalus .
- Presence of occupant injuries : These types of alterations refer to the presence of structural and vascular malformations Intracerebral, masses or collections. Some of the pathologies leading to this type of injury are: Cysts , Tumors, hematomas, malformations Arteriovenous, etc.
- Presence of anomalous substances : These types of alterations refer to the presence of deposit or metabolic diseases Such as Alexander's disease, Canavan's disease, metabolopathies, etc.
Bone anomalies
As for cases of macrocephaly that are due to bone abnormalities, we can find:
- Macrocephaly due to early closure of cranial sutures .
- Macrocephaly due to systemic bone alterations : Rickets, osteogenesis, osteoporosis, etc.
Diagnosis
Macrocephaly is a neurological pathology that can be detected during the gestation phase.
Routine health checks through ultrasound ultrasound are able to detect abnormalities in cranial Early stages of gestation, when macrocephaly has a congenital or prenatal origin.
However, it is not always possible to detect it before birth, because many cases of macrocephaly occur secondary to others Medical pathologies.
It is usually detected in pediatric consultations through the measurement of the cranial perimeter. In addition, different analyzes To determine the etiologic cause.
Specifically, clinical examination should include (Martí Herrero and Cabrera López, 2008):
- Physical examination of the skull : An accurate measurement of the cranial perimeter should be performed and a comparison with the standards Of growth.
- Neurological examination : It will also be necessary the evaluation of different neurological factors (gait, motor coordination, Sensory deficits, cerebellar signs, reflexes, etc.).
- Pediatric examination : In this case, the study will focus on the etiological cause of macrocephaly through analysis of Genetic pathologies, neurological, etc.
- Complementary tests : In addition to the physical and neurological examination, some explorations may be required Complementary measures such magnetic resonance , Computed tomography, X-rays , lumbar puncture , Electroencephalography , etc. Especially in those Macrocephaly of unknown origin.
Is there treatment for macrocephaly?
At present there is no curative treatment for macrocephaly. Generally, the treatment is symptomatic and will depend on the diagnosis Precise etiology.
After detecting macrocephaly, it is necessary to determine the underlying cause to design the best therapeutic approach, since in the cases in the That hydrocephalus is the main cause of macrocephaly, it will be necessary to use surgical interventions.
Therefore, the treatment will have a marked palliative value. Pharmacological approaches may be used to control medical complications, As non-pharmacological approaches to the neurological and cognitive sequelae.
In all cases of macrocephaly and other disorders of cranial development, it is essential that a neurological examination and / or Neuropsychological to examine the level of general functioning: developmental deficits, cognitive functions, linguistic deficits, motor skills, etc. (National Institute of Neurological Disorder and Stroke, 2016).
Some of the non-pharmacological interventions that can be used in the symptomatic cases of macrocephaly are (Martí Herrero and Cabrera López, 2008):
- Neuropsychological rehabilitation .
- Early stimulation .
- Special education.
- Occupational Therapy .
Forecast
The prognosis and evolution of this pathology depends fundamentally on the origin and associated symptomatology.
In children who have a Microcephaly Benign, the absence of significant symptoms or medical complications will allow them to develop all the Areas with normality (Erickson Gabbey, 2014).
However, in many other cases future prospects will depend on the presence of medical complications (Erickson Gabbey, 2014). In general, Children who suffer from macrocephaly will present significant generalized developmental delays and will therefore require therapeutic intervention To promote the acquisition of new skills and the achievement of an efficient functional level.
Bibliography
- AAN. (2016). Chapter 13. Common Problems in Pediatric Neurology . Retrieved from the American Academy of Neurology.
- Erickson Gabbey, A. (2014). What is Macrocephaly? Retrieved from Healthline.
- García Peñas, J. J., & Romero Andújar, F. (2007). Alterations of the cranial perimeter: microcephaly and macrocephaly. Pediatr Integral , eleven (8), 701-716.
- Martí Herrero, M., & Cabrera López, J. (2008). Macro- and microcephaly. Cranial growth disorders. Spanish Association of Pediatrics .
- Mellea Escobar, G., Cortés Zepeda, R., Avaria Benaprés, M.A., & Kleinsteuber Sáa, K. (2014). Clash of Macrocephaly in Children . Retrieved from Journal Electronic Pediatrics.
- Microcephaly. (2016). Microcephaly . Retrieved from Mycocephaly.org.
- Network, M.-C. (2016). Macrocephaly-capillary malformation . Obtained from M-CM Network.
- NIH. (2003). Cephalic Disorders Fact Sheet . Retrieved from the National Institute of Neurological Disorders and Stroke.
- NIH. (2015). Increased head circumference . Obtained from MedlinePlus.
- Vertinsky, A. T., & Barnes, P. (2007). Macrocephaly, Increased Intracranial Pressure, and Hydrocephalus in the Infant and Young Child. Top Magn Reson Imaging , 18 (1).