Symposium 2003

The Influence of Periventricular Leukomalicia on Child Development: An N or 1 Study

by Sarah Pachulicz


“Baba!” “Would you like to have the ball? Here is your walker. Come on, Alex, let’s walk to the ball!” Alex is two years old, yet he does not walk, sit up or speak. He suffers from Periventricular Leukomalicia (PVL). This means death of the white matter of the brain, caused by oxygen deprivation before, during or shortly after birth (NINDS, 2002). The impact of this condition on his motor and language abilities shall be examined in the following discussion.

Introduction

Starting at the moment of conception, the developing life is very susceptible to teratogens that can severely impact the mental and physical abilities of the newborn baby. All organs and body parts have a critical period during which the influence of teratogens is especially harmful. The central nervous system has the longest critical period, lasting throughout the entire pregnancy (Berger, 2001).


The intrauterine life can be hazardous for the baby, but the real work begins after
birth: the newborn has to make sense of all the incoming stimuli, and learn to orient him/herself in the great big world. Theorists once argued whether infants perceive a "blooming, buzzing confusion", as Wm. James put it, or whether they arrive with a "tabula rasa" and have to learn everything from scratch (Berger, 2001).


We know now that neither one of these theories holds up. Instead we found that "the neonate has been grossly underestimated in the past. Thinking of him as a 'passive lump of clay' has shut our eyes to his complexity. He offers many complex responses from the first for generating attachment from his caregivers" (Brazelton, 1990). This complexity is only possible because of the wonderful construction of the brain. The first reflexes are hardwired in order to elicit a care giving response from the parent. This first attachment to the caregiver can be an important factor for the psychosocial development later in the children's life. (Berger, 2001). That is why disturbances in this process, either of organic
or environmental nature, can be so very harmful. Especially for prematurely born infants, the brain is most susceptible to injuries due to stress during birth, rupturing of blood vessels and lack of oxygen. The most vulnerable area is around the ventricles, where the tissue is especially fragile and likely to rupture. Any scarring in this area shows up white on an MRI, so the name for damage around the ventricles is "periventricular leukomalaicia" (leuko = white, malaicia = softening) (Carter, 2001). The fibers that control voluntary movement in the legs run through this area, which means that children with this kind of neurological damage often have difficulty controlling their legs. Other
common symptoms include auditory processing problems, cortical visual impairment, increased muscle tone and speech problems. In severe cases mental retardation can occur (Carter, 2001).


PVL is a subcategory of Cerebral Palsy (CP), which has first been described over a hundred years ago by W.J.Little. He documented approximately 200 cases, describing "spastic rigidity" due to "abnormal parturition and asphyxia at birth" (Hanesian, Paez and Williams, 1990). CP can have either prenatal, perinatal or postnatal onset and is characterized by the following six components: spasticity (stiffness of musculature and slow movement), athetosis (abnormal amount and type of involuntary movement), rigidity (decreased motion, the muscles are partially contracted all the time), ataxia (incoordination due to disturbance in the sense of balance), tremor (involuntary movements in a rhythmical manner), and atonia (lack of tone and failure of muscles to respond to stimulation) (Hanesian, Paez, and Williams, 1990).


Since most newborns have very limited voluntary movement, an impairment in motor development may not be obvious until the child fails to reach the developmental milestones on time. Yet it is crucial to detect developmental abnormalities early, because the brain's ability to generate new pathways is greatest the younger the infant (Carter, 2001). In order to fully comprehend the impact of neurological damage on the child's development one must first have an understanding of the abilities that a normally developing infant is expected to have. For the purpose of this study we will mainly consider sitting, walking , and language development. A more extensive list can be found in Appendix A. The ages given are only averages, a child can show moderate deviation in
either direction and still be considered normal:

By three months of age the child should lift the head and chest when lying on his/her stomach and wiggle and kick with arms and legs. They should make cooing, gurgling sounds and communicate hunger, fear and discomfort through crying or facial expressions (Smith and Powell, 1994).


By six months of age children should pull up to a sitting position if an adult holds their hands, sit with very little support and roll over. They should babble, make "sing-song" sounds, laugh and squeal with delight, and scream if annoyed (Smith and Powell, 1994).


By 12 months of age children should sit well without support, crawl on hands and knees, pull themselves to stand or take steps holding onto furniture, and stand alone for a few seconds. They should make noises that resemble language, say their first word, understand simple commands and try to "talk" with parents (Oesterreich, 1995).

By 24 months of age children are very mobile, run, can go up steps, and can take steps backward. They have a vocabulary of several hundred words, try to hum and sing, and enjoy imitating adults, e.g. "talking on the phone" (Smith and Powell, 1994).

The question

Given that the development of a human baby from zygote to newborn is a complex process, many factors have to act together in an almost miraculous way to form a new life. When one of these factors is missing, or other, harmful factors come into play, the result can be a disturbance in normal development.
The objective of this longitudinal study is to determine the effects of PVL on the
motor development of Alex S., age two.Alex was born on December 2, 2000, five weeks prematurely. His birth weight was 3048 grams, which is in the normal range. His mother suffered from placenta previa (a condition where the placenta blocks the vaginal opening) and experienced some vaginal bleeding during the last three months of pregnancy. Alex was delivered by emergency C-section after his mother started losing large volumes of blood in the 35th week. Despite
the circumstances Alex received an Apgar-score of 10 and seemed to be doing fine. When he was 28 days old he caught a virus that affected his respiratory system and spent 5 days on a respirator in the Intensive Care Unit; he had to be on oxygen for one month after he returned home. He also wore a sleep apnea monitor during naps and at night.


His parents first became concerned when he did not attempt to sit at six months.
When he still had not shown any improvement in motor abilities at nine months, a more thorough examination was performed and Alex was diagnosed with Periventricular Leukomalaicia.He now receives physical therapy twice a week, occupational therapy twice a week, and speech therapy twice a month. While this study was in progress Alex received treatment with Botox.

At the beginning of the study the author hypothesized that the Botox treatment would help Alex gain control over his leg muscles so that he would be able to take at least 10 steps by himself by the end of the study.

Method

The timeframe of the study was September 15, 2002 to November 15, 2002. Alex' age at the beginning of the study was 21 months 2 weeks (1.9 years). He was weighed and measured at the beginning and end of the study, with results in the normal range. His therapists and parents agreed that the skills he was most deficient in were standing, walking and talking. In order to monitor his development in these areas a data sheet was developed that would allow us to record five measurements: the number of steps taken with a walker, the number of steps taken alone, the time (in seconds) he can stand alone, the number of spoken words and the number of signed words (his parents are teaching him rudimentary sign language). The observers were also asked to record
behaviors such as stacking blocks, understanding commands, and responses to spoken words on the Data Sheet in a more general fashion.
In order to avoid biased results these data were collected every Tuesday and Friday by three different people: The occupational therapist, Alex' mother, and the author herself. All three data collections showed good inter-rater reliability. (for Sample Data Sheet see Appendix B)
 

Results


 

Conclusion/discussion


The data show a substantial deficit in motor and language development. At the end of the study two-year old Alex was able to say 11 words and sign 11 (different) words, stand alone for two seconds, walk 21 steps with his walker and two without his walker. The normal range for children his age is having a vocabulary of several hundred words, walking alone and running alone. The author's hypothesis that Alex would be taking 10 steps alone by the end of the study was clearly an overestimate, yet it seems that with further therapy Alex will be able to reach this goal within the near future.


The graph above shows a summary of Alex' improvements over the two-months
period of this study. During the first two weeks of the study Alex' muscles were very rigid, resulting in extreme stiffness in leg-, arm-, and torso muscles. He had, however, learned to use the tense muscles to his advantage and to take a few, stiff-legged steps with the walker. The red line on the graph indicates the number of steps taken with the walker, and the great dip is when the Botox treatment started. Botox is often used for non-invasive face-lifts, it reduces wrinkles by paralyzing facial muscles. This paralyzing property was utilized to reduce the rigidity in Alex' muscles. Botox was injected into his hamstrings and significantly reduced the tenseness. However, since Alex had incorporated the stiff muscles in his walking mechanics, he did not know how to flex or relax his muscles, rendering his legs limp and useless. This is why for a few days he was not able to take
steps at all, and after that had to relearn how to use his legs. His balance seems to
continue to be problematic, but with a walker to hold on to his walking skills have
improved greatly. Since the wiring in the brain for walking skills is usually far advanced by age two, it is harder for him to learn it now; and it is crucial that he learns fast while the brain is still young enough to rewire.

His speech shows a slow but steady improvement and is not affected by the Botox treatment. Even though the data seem to imply that he is very much behind in all areas we must be careful to remember that they do not represent a comprehensive picture of his
abilities. In other areas that are more complicated to assess and have therefore be
excluded from this study he shows age-appropriate behavior: in contrast to his very limited speech his understanding of language is immense. He was able to point correctly to 12 body parts upon command, including hair, eyes, teeth, tongue, ears, and others. This is a skill that is only expected at age two-and-a-half to three.

He also displays very advanced block-stacking, color-recognition and shape-sorting skills. From the fact that he develops intellectually normal in some areas we can assume that he does not have mental retardation, but that only a few areas of the brain are damaged. From the pattern of his speech development and his ability to understand language we might pose the hypothesis that there could be some damage to Broca's area, whereas Wernicke's area seems to be intact.
Alex is fortunate enough to receive the care and therapy that will enable him to fully develop his maximum potential. It is a reasonable assumption that he will one day be able to walk unassisted. His story is a wonderful illustration of the nature-nurture interrelation: nature has given him certain limitation, but with the right nurture these limits can be stretched very far.




Bibliography
Berger, Kathleen Stassen. (2001). The Developing Person Through the Life Span. 5th Edition. Worth Publishers. New York, NY.
Brazelton, T. Berry. (1990). Neonatal Assessment. In: The Course of Life, Volume I, Infancy. Greenspan, Stanley I. and Pollock, George H., editors. US Government Printing Office. Washington, DC.
Carter, Sheena L. (2001). Motor Impairment Associated with Neurological Injury in Premature Infants.
URL Document http://www.comeunity.com/disability/cerebral_palsy/cerebralpalsy.html
Hanesian, Helen, Paez, Patricio, and Williams, Daniel T. (1988). The Neurological Impaired Child and Adolescent. Handbook of Clinical Assessment of Children and Adolescents. New York University Press. New York, NY.
National Institute of Neurological Disorders and Stroke (NINDS).(2002). What is Periventricular Leukomalacia? National Institutes of Health. Bethesda, MD.
Oesterreich, Lesia. (1995). Ages & stages - newborn to 1 year. In L. Oesterreich, B. Holt, & S. Karas, Iowa family child care handbook [Pm 1541] (pp. 192-196). Ames, IA: Iowa State University Extension.
Smith, Charles A. and Powell. Joyce. (1994). The 1st year. In *Developmental milestones: A guide for parents*. Manhattan, KS: Kansas State University Cooperative Extension Service.