Human Anatomy at Colby

Spina bifida arises from abnormalities in the process that is responsible for the development of the central nervous system. It is apparent visually as a defect in the posterior of the vertebrae, which results in a protrusion of the meninges. Essentially, the spinal column does not close completely. While documentation of this disease dates back to the 17^th century, it was understudied until recently. In this presentation, we will discuss spina bifida and show how the diagnosis and treatment has changed over time, as well as touch upon new, cutting edge techniques for treatment.

There are multiple types of spina bifida, including myelomeningocele, which is the most common and also one of the most severe. Myelomeningocele can be diagnosed in utero, or seen at birth. Children born with spina bifida can experience a range of physical impairments, from bladder and bowel dysfunction to lower limb paralysis. Due to the defect of the vertebrae, other clinical diagnoses are linked to spina bifida, including hydrocephalus and meningitis which feed into a staggeringly high early mortality rate. In truth, the treatment of spina bifida occurs through the treatment and prevention of other disorders linked to the disease in order to ensure a long, fulfilling life for the patient.

             Though the term spina bifida was coined in the 17^th century, no effective treatment was found for hundreds of years. At one point, it was determined that spina bifida was untreatable due to the overwhelming amount of failed attempts by surgeons to treat the disease. It wasn’t until the 1950’s, with the case of Casey Holter, that a shunt which helped to relieve the fluid on the brain was created. The shunt worked by implanting a tube with one end in the brain, the other in the jugular vein. Via this channel, the cerebrospinal fluid was able to drain from the brain and enter the bloodstream. The 1960’s showed the first drastic progress in spina bifida treatment due to this Spitz-Holter shunt. While previous survival rates were 10-12%, the introduction of this shunt caused early mortality rates to rapidly declined to about 20%.

            Although the future for spina bifida seemed bright with the drastic shift in mortality rates, the 1970s and 80s proved as challenging times for parents and the medical community. While shunts had allowed early mortality rates to decline, the life expectancy for children of spina bifida were not living long lives and the medical community questioned the quality of life as well. This led to discussions about whether children born with more severe forms of spina bifida should receive treatment. With the help of research which tracked parental input, it was decided that treatment would be standard for children born with spina bifida.

            In 2003, the National Institutes of Health broke group with more medical advancements to better treat spina bifida. In this study, 183 fetuses were randomized and 91 received fetal repair, 92 postnatal. Repair includes such procedures as closing the defect over the spinal cord or reconstructing any spinal deformities. This study was promising, showing that children who had undergone fetal repair were 50% as likely to need a ventricular shunt, were less likely to develop a Chiari malformation, a condition in which the cerebellum and brainstem push into the spinal canal. Additionally, children that underwent fetal repair showed higher standardized test scores, indicating a lesser cognitive impairment.  

            New advancements in the field with spina bifida include eliminating the need for patients to need shunts, which have not been updated since the 1950s when they were created. This treatment, ETV/CPC treatment, was developed by Benjamin Ward from Boston Children’s Hospital. In ETV/CPC treatment, ETV is used to create a passageway in the third ventricle of the brain, which allows cerebrospinal fluid to drain. CPC is then used to reduce the choroid plexus so less cerebrospinal fluid is produced.

Kiana Chabot, Kacey LaBonte, Merel van Gijzen, Annabelle Fischer

Sources:

About Fetal Surgery for Spina Bifida (Myelomeningocele). Children’s Hospital of Philadelphia. (Accessed 17 January, 2018 at http://www.chop.edu/treatments/fetal-surgery-spina-bifida/about)

Fletcher JM, Brei TJ. Introduction: Spina Bifida: A Multidisciplinary Perspective. Developmental Disabilities Research Review 2011; 16(1)

ETV/CPC Procedure. Boston Children’s Hospital. (Accessed 17 January, 2018 at http://www.childrenshospital.org/conditions-and-treatments/treatments/etv-cpc-procedure)

Laurence KM. The Natural History of Spina Bifida Cystica. Archives of Diseases in Childhood 1964;39.

Mertens P. Spina Bifida and primary prevention. Orphanet Journal of Rare Diseases 2012; 7(2).

Mohd-Zin SQ, Marwan AI, Abou Chaar MK, Ahman-Annuar A, Abdul-Aziz NM. Spina Bifida: Pathogenesis, Mechanisms, and Genes in Mice and Humans. Scientifica 2017; 2017.

Pruitt LJ. Living With Spina Bifida: A Historical Perspective. Pediatrics 2012; 130(2).

I believe that all humans who have access to education should be required to learn about what exists inside our bodies and how they work. Isn’t who we are also what we are? I approached human anatomy and physiology more as a discovery of myself. There was this deep-rooted desire to explore each groove of the vertebrae and each curvature of the organs. I knew that in class we were learning a basic template for the body, and that in reality, each individuals’ anatomy had its own features that made us unique, such as the shapes of our skulls or the muscular divots in our backs.

One way I experienced this was during the pig heart dissection. I compared my pig heart, which was tightly packed with adipose tissue and had narrow pulmonary arteries, to a classmate’s, which in turn had a large aortic arch and clear coronary arteries that wrapped around the base. We concluded that these characteristics were not only important in making each individual pig, or organism in general, unique, but also because it gave us information about its superficial appearance and the life it had.

We further challenged this idea on a skull we had in the laboratory. The date of the skull and the presence of a rare sutural bone suggested the person was indigenous to a certain Peruvian tribe that has been historically known for sutural bones and laboratory donations. Additionally, the loss of teeth in the skull implied that the person had been a mouth breather, which was further explained by a crooked nasal bone, which had potentially been broken during his or her life time. As I continued to compare the special characteristics that distinguished each individual’s anatomy, I was brought back to this feeling of curiosity about myself.     

It struck me that, although I saw the class as more of a self-discovery, I would never actually be able to see these unique features that made up my own body on the anatomical and physiological level at which I was learning about them. In fact, the only people that had the opportunity to actively witness and handle the billions of possible variations our bodies take are surgeons. On January 31, Obstetrics and Gynecology Specialist Dr. K. Nathan Parthasarathy presented as a guest speaker and talked a little about the benefits of being a surgeon. One especially powerful story he told was about perhaps the only man ever to have safely handled and observed his own deep anatomy. Leonid Rogozov, 27 years old at the time, was the only surgeon stationed at the Soviet base in Antarctica in 1961. He had the misfortune of getting appendicitis and, being the only surgeon, saved his own life by performing an appendectomy on himself. Dr. Parthasarathy mentioned Rogozov’s story to make the point that a doctor is not more skilled because he or she has had the experience, and therefore, empathizes with the patient. If this is true, I thought, then a skilled physician must be the product purely curiosity, and originally, the innate desire to understand the self.   

January, 2018 – Annabelle Fischer