The brain is one of the most complex organs of the human body. It has been the subject of study for centuries. Further, the brain and its complex subcortical and cortical structures are highly advanced and interwoven. Understanding the anatomy of the brain can be improved through the study of the major vascular structures of the region studied. For the purpose of this assignment, the author will examine the cerebellum and the major vascular inputs and outputs of the area.
The Cerebellum
The cerebellum is a component region of the brain known as the hindbrain or rhombencephalon and is anatomically located dorsal, immediately inferior to the occipital and temporal lobes, within the posterior cranial fossa, posterior to the pons. This brain region is divided into two distinct regions: the metencephalon and the myelencephalon. The metencephalon is superior whereas the myelencephalon is inferior. The metencephalon region is understood to primarily control motor functions such as balance, standing or walking, and movement of the hands and feet.
The metencephalon is divided medially by the vermis. The cerebellum is divided from the vermis into two hemispheres or zones. Three lobes complete the anatomical structure of the metencephalon: posterior, anterior, and flocculonodular lobes.
Vascularly, the cerebellum receives its primary input and output through three pairs of arteries: the superior cerebellar artery (SCA), the anterior inferior cerebellar artery (AICA), and the posterior inferior cerebellar artery (PICA). The SCA and AICA are components or branches of the basilar artery, and the PICA is a branch of the vertebral artery. Together, these arteries provide venous input and output to the region of the cerebellum. Venous drainage of the cerebellum is performed by the superior petrosal, transverse, and straight dural venous sinuses.
Transient Ischemic Attack (TIA) and Impacts on the Cerebellum
While research is evolving in this area, a transient ischemic attack or TIA is a phenomenon by which a temporary cerebrovascular event occurs, temporarily interrupting arm or leg function on one side of the body, sudden confusion or difficulty understanding, difficulty with vision, dizziness, loss of balance, and or a severe headache with no known cause. Transient ischemic attack (TIA) is a transient neurological dysfunction triggered by focal brain, medulla spinalis, or retinal ischemia, also known as a “small stroke.” Many times, a TIA will present with similar symptoms as a stroke, but by contrast with a stroke, symptoms abate quickly. Evidence shown in previous studies has demonstrated that a TIA can be regarded as one of the main, under-recognized, and modifiable risk factors for stroke (Easton, 2009).
A Swedish study recently attempted to identify biomarkers that could be used to identify the occurrence of a TIA. Diagnosing a TIA is difficult due to the transient symptomology, precisely the speed of onset and abatement. The study aimed to investigate resting-state patients to identify further individual metrics that could differentiate patients who have experienced a TIA from those with healthy controls. (Ma, 2022).
The study aimed to identify biomarkers that could be used to determine individual risks of TIA when compared with healthy individuals without biomarkers present. Furthermore, the researchers’ direct aim was to provide evidence of understanding of the neuropathology of TIAs, thereby enabling a more reliable and predictive clinical diagnosis. Researchers utilized functional MRIs and data from 48 patients by demographically matching healthy controls and comparing the difference in three distinct areas: dynamic amplitude of low-of low-frequency fluctuation (d-fALFF), and dynamic regional homogeneity (d-ReHo).
Researchers utilized ALFF, which measures the signal strength of spontaneous neural activity using low-frequency oscillations (LFOs), fractional ALFF (f-ALFF), which characterizes the relative contribution of an LFO to the entire range (Zoe et al., 2008), and regional homogeneity (ReHo) which reflects the coherence of local neural activity among spatially neighboring regions (Chen, 2016).
Researchers found that biomarkers are indeed present compared to healthy patients in those who have experienced a TIA. The researcher’s findings are clinically relevant to diagnosing a TIA and a predictor for future attacks. Given the spontaneous nature of a TIA, the author concludes that there is no statistically reliable or valid method of predicting a TIA, only the post-episode diagnosis of a TIA. This process can be simplified using the identified biomarkers.
This paper’s author re-engineered our prompt’s final question and inverted the professor’s logic. To clearly understand the area of the cerebellum and its associated arterial pathways, the author found it most logical to identify a disorder and discuss the function associated with it. The author believes the means reached the professor’s end.
Conclusion
The cerebellum is a fascinating brain region that controls many daily activities. The onset of a TIA presents many challenges for researchers and patients. The sudden occurrence of a TIA and abatement leaves little time for researchers to investigate. The author hypothesizes that many TIAs are undiagnosed.
If I were to put my cerebellum to sleep for a day, I highly doubt I would get my studies done. I could not walk confidently to the restroom or find something to eat. I would have difficulty holding my young children.
In summation, the cerebellum controls so much of what we do in our daily lives. Understanding its function, input, and sinus pathways leads to a greater understanding of anatomical directions, profusion, arterial flow, and sinus flow, and the potential impacts disruption of this region may cause in day-to-day life.
Chen, J., Sun, D., Shi, Y., Jin, W., Wang, Y., Xi, Q., et al. (2018). Dynamic Alterations in Spontaneous Neural Activity in Multiple Brain Networks in Subacute Stroke Patients: a Resting-State fMRI Study. Front. Neurosci. 12:994. doi: 10.3389/fnins.2018.00994
Easton, J. D., Saver, J. L., Albers, G. W., Alberts, M. J., Chaturvedi, S., Feldmann, E., et al. (2009). Definition and evaluation of transient ischemic attack: a scientific statement for healthcare professionals from the American Heart Association/American Stroke Association Stroke Council; Council on Cardiovascular Surgery and Anesthesia; Council on Cardiovascular Radiology and Intervention; Council on Cardiovascular Nursing; and the Interdisciplinary Council on Peripheral Vascular Disease. The American Academy of Neurology affirms the value of this statement as an educational tool for neurologists. Stroke 40, 2276–2293. doi: 10.1161/STROKEAHA.108.192218.
Ma, H. (2022). The predictive value of dynamic intrinsic local metrics in transient ischemic attack. APA 6th – American Psychological Association, 6th Edition.