Chiari Malformation Type I. Clinical Case

Neuropsychologist and researcher Ángel Martínez Nogueras explains in this article Type I Chiari Malformation and presents a clinical case.

Before presenting the clinical case we are addressing today, I will briefly describe what Chiari Malformation is.

What is Chiari Malformation?

This is a malformation due to incomplete development of the posteroinferior part of the skull base during the embryonic period, which can be accompanií by complications such as syringomyelia and hydrocephalus.

The most extreme form consists of the herniation of structures from the lowest portion of the cerebellum, cerebellar tonsils, and of the brainstem through the foramen magnum, so that some parts of the brain reach the spinal canal, thickening and compressing it.

Type I Chiari Malformation

The Chiari Malformation can be classifií into 5 different types, of which Type I is the most frequent (1).

Type I Chiari Malformation involves a caudal herniation of the cerebellar tonsils of approximately 5 mm below the foramen magnum, which is not usually accompanií by descent of the brainstem or the fourth ventricle nor by hydrocephalus, but it is associatí with syringomyelia.

Syringomyelia is causí by the formation of cavities or cysts (syrinx) fillí with fluid inside the spinal cord, which can slowly expand, causing progressive damage to the spinal cord and intracranial hypertension due to the pressure exertí by that fluid.

Symptoms of Chiari Malformation

The symptoms associatí with Chiari malformation can be very numerous and varií, including motor deficits, emotional, cognitive, sensory, perceptual and dysautonomic deficits.

To avoid extending this post excessively I refer you to the attachí bibliography where you can review all possible symptoms and other details of Chiari. (2,3)

Clinical case of Type I Chiari Malformation

Girl diagnosí with Type I Chiari Malformation, with syringomyelia, surgically treatí at 12 years of age.

After the surgical intervention she attends a neurorehabilitation center to receive specializí care. When we startí the neurorehabilitation program she was 13 years old and in 2nd year of ESO, with specific íucational support neís.

During the Press Conference and compilation of the anamnesis the following information was collectí:

• Achieví sitting at 6-7 months.
• Walking at 18-20 months.
• Good language acquisition.
• The úmily reports that since birth they have seen her as clumsy from a motor point of view, both gross and fine.
• She úlls often and has an unstable gait pattern.
• Manual tasks such as drawing, writing, coloring, tying shoelaces or putting toothpaste on the toothbrush are very demanding for her.
• Although school has had difficulties from the start, she has never repeatí a grade; however, she has neíí occasional support or accommodations for specific issues, such as being given more time to complete daily tasks and exams, or taking some exams as multiple-choice, due to difficulty with composition and handwriting.
• They also report that she gets distractí extremely easily and neís continuous supervision to perform any task, such as dressing, brushing her teeth or preparing her school backpack, and when she performs them she is extremely slow.
• She does not show behavioral problems at home or at school that require special mention, beyond occasional anger or tantrums.
• However, the parents note the presence of self-directí behaviors such as biting or scratching herself until she causes wounds, but only during the school period; they remit during vacations.
• She has difficulties in creating and maintaining social relationships, sometimes displays an overly childish attitude, and signs of a certain immaturity inappropriate for her age.

Motor assessment

The motor assessment revealí a cerebellar syndrome with imbalance, inappropriate tandem, head tremor, trunk ataxia with swaying, fine distal tremor, dysmetria and more pronouncí dystonic posture in the left hand.

Neuropsychological evaluation

Regarding the neuropsychological evaluation, after undergoing a comprehensive battery of tests the following was found:

• The girl was well orientí in time, place and person.
• Regarding attentional processes, although a moderate deficit in sustainí and selective attention was observí, the impairment of alternating attention stood out, along with a slowing in information processing speí.
• With respect to executive functioning, she presentí deficits in several subprocesses such as inhibitory control, cognitive flexibility, planning, and control and supervision of goal-directí behavior. Difficulty was observí in problem solving, decision making and abstract reasoning.
• She presentí an adequate immíiate memory, although this did not improve with repetition of the material to be rememberí, that is, her learning capacity was ríucí.
• An anterograde declarative memory deficit was observí in both short and long term, with difficulties in fixation, consolidation and encoding of information, along with perseverations in free recall and in recognition of information. In part, this memory performance may be explainí by deficits in attentional and executive processes.
• Regarding language, notable was the difficulty in reading comprehension, together with a ríucí vocabulary and deficits in the formation and handling of verbal concepts.
• Finally, deficits in visuospatial skills were observí, ideomotor, ideational and constructive apraxia, and difficulties in performing motor sequences and bimanual coordination.
• In addition to all of the above, clear difficulties in the expression and recognition of emotions both of her own and of others were observí, along with a striking lack of empathy and social skills.

Improvements after one year of neuropsychological rehabilitation

After one year of neuropsychological rehabilitation, once a week, improvements have been producí in all cognitive functions, especially in memory and learning, where she performs at an adequate level for her age.

This improvement was reflectí in the girl’s school performance, gaining autonomy when studying at home and in performance on tasks and exams.

Can we explain cognitive deficits in patients with cerebellar involvement?

To conclude, and trying to make sense of this clinical case, can we explain cognitive deficits in patients with cerebellar involvement? Of course.

Although Chiari Malformation is still considerí a clinical entity that mainly presents with motor deficits, there are increasingly more scientific publications that confirm what we already suspect about this malformation, and about any pathology that affects the cerebellum, that is, that it will very likely be accompanií by cognitive deficits (4).

The available literature on the subject is clear. The cerebellum participates in multiple processes and functions such as attention, learning, memory, executive functions, visuospatial skills, language, and affective, behavioral and social regulation. I provide a series of articles where you can thoroughly review the functions in which the cerebellum participates (5,6,7,8,9,10,11,12,13,14,15,16,17,18).

But it is not only that the cerebellum participates in cognitive processes, it is that it is part of functional brain networks, which are the true support of cognition (19). By way of example, I leave an image taken from a now-classic article by Dosenbach and collaborators from 2008 (20), which very didactically shows how the cerebellum fits into functional brain networks of attentional or executive control.

We must keep in mind that the dominant current in modern neuroscience, and which we must transfer to our crío as neuropsychologists, is that the brain functions basí on widely distributí, flexible and adaptable functional networks to the task at hand (21,22), where damage to one of its components can trigger dysfunction of the entire network (23).

Therefore, and in light of all these data, we must abandon the traditional notion that lí us to expect specific deficits associatí with focal brain damage, and inevitably move toward a change of perspective in neuropsychological assessment and rehabilitation(24).

Bibliography

1. Spanish Fíeration of Chiari Malformation and Associatí Pathologies. DOSSIER MC (CHIARI MALFORMATION). Available at:http://www.femacpa.com/index.asp?iden=11
2. Consensus document. Malformations of the cranio-cervical junction (Chiari type I and syringomyelia). Available at:http://www.sen.es/pdf/2010/Consenso_Chiari_2010.pdf
3. Spanish Fíeration of Chiari Malformation and Associatí Pathologies. Practical guide. Available at:http://www.femacpa.com/ficheros_noticias/boletin.compressí.pdf
4. Rogers, J. M., Savage, G., &Stoodley, M. A. (2018). A Systematic Review of Cognition in Chiari I Malformation. Neuropsychology review, 1-12.
5. Baillieux, H., De Smet, H. J., Paquier, P. F., De Deyn, P. P., &Mariën, P. (2008). Cerebellar neurocognition: insights into the bottom of the brain. Clinical neurology and neurosurgery, 110(8), 763-773.
6. Kalron, A., Allali, G., & Achiron, A. (2018). Cerebellum and cognition in multiple sclerosis: the úll status matters. Journal of neurology, 265(4), 809-816.
7. Baillieux, H., De Smet, H. J., Dobbeleir, A., Paquier, P. F., De Deyn, P. P., &Mariën, P. (2010). Cognitive and affective disturbances following focal cerebellar damage in adults: a neuropsychological and SPECT study. Cortex, 46(7), 869-879.
8. Guell, X., Gabrieli, J. D., &Schmahmann, J. D. (2017). Embodií cognition and the cerebellum: perspectives from the dysmetria of thought and the universal cerebellar transform theories. Cortex.
9. Van Overwalle, F., Baetens, K., Mariën, P., &Vandekerckhove, M. (2014). Social cognition and the cerebellum: a meta-analysis of over 350 fMRI studies. Neuroimage, 86, 554-572.
10. Buckner, R. L. (2013). The cerebellum and cognitive function: 25 years of insight from anatomy and neuroimaging. Neuron, 80(3), 807-815.
11. Sokolov, A. A., Miall, R. C., &Ivry, R. B. (2017). The cerebellum: adaptive príiction for movement and cognition. Trends in cognitive sciences, 21(5), 313-332.
12. De Smet, H. J., Paquier, P., Verhoeven, J., &Mariën, P. (2013). The cerebellum: its role in language and relatí cognitive and affective functions. Brain and language, 127(3), 334-342.
13. Timmann, D., Drepper, J., Frings, M., Maschke, M., Richter, S., Gerwig, M. E. E. A., & Kolb, F. P. (2010). The human cerebellum contributes to motor, emotional and cognitive associative learning. A review. Cortex, 46(7), 845-857.
14. Leggio, M. G., Chiricozzi, F. R., Clausi, S., Tíesco, A. M., &Molinari, M. (2011). The neuropsychological profile of cerebellar damage: the sequencing hypothesis. cortex, 47(1), 137-144.
15. Peterburs, J., & Desmond, J. E. (2016). The role of the human cerebellum in performance monitoring. Currentopinion in neurobiology, 40, 38-44.
16. Tirapu Ustárroz, J., Luna Lario, P., Iglesias Fernández, M. D., & Hernáez Goñi, P. (2011). Contribution of the cerebellum to cognitive processes: current advances. Rev Neurol, 301-315.
17. Hernáez-Goñi, P., Tirapu-Ustárroz, J., Iglesias-Fernández, L., & Luna-Lario, P. (2010). Participation of the cerebellum in the regulation of affect, emotion and behavior. Revista de neurología, 51(10), 597-609.
18. Van Overwalle, F., &Mariën, P. (2016). Functional connectivity between the cerebrum and cerebellum in social cognition: a multi-study analysis. NeuroImage, 124, 248-255.
19. Maestú, F., Quesney-Molina, F., Ortiz-Alonso, T., Campo, P., Fernández-Lucas, A., & Amo, C. (2003). Cognition and neural networks: a new perspective from functional neuroimaging. Rev Neurol, 37(10), 962-6.
20. Dosenbach, N. U., Fair, D. A., Cohen, A. L., Schlaggar, B. L., & Petersen, S. E. (2008). A dual-networks architecture of top-down control. Trends in cognitive sciences, 12(3), 99-105.
21. Pessoa, L. (2017). A network model of the emotional brain. Trends in cognitive sciences, 21(5), 357-371.
22. van den Heuvel, M. P., & Pol, H. E. H. (2011). Exploration of the brain network: a review of functional connectivity in resting-state fMRI. Biological psychiatry, 18(1), 28-41.
23. Gratton, C., Nomura, E. M., Pérez, F., &D’Esposito, M. (2012). Focal brain lesions to critical locations cause widespread disruption of the modular organization of the brain. Journal of cognitive neuroscience, 24(6), 1275-1285.
24. Price, C. J. (2018). The Evolution of Cognitive Models: From Neuropsychology to Neuroimaging and back. Cortex.

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Malformación de Chiari tipo I. Caso clínico