Category: Brain

Dec 09

Epilepsy and the Corpus Callosotomy

The corpus callosum, an intricate band of nerve fibers deeply ensconced within the brain, plays a pivotal role in bridging the two cerebral hemispheres. This neurological superhighway facilitates the exchange of information between the brain’s halves, but it also harbors a darker aspect—it can act as a conduit for the spread of debilitating seizure impulses from one hemisphere to the other. A corpus callosotomy, a surgical procedure involving the severing of this neural bridge, emerges as a profound intervention that effectively disrupts the propagation of seizures between brain hemispheres. Though this procedure does not render seizures completely impotent, it significantly mitigates their intensity by confining them to their originating hemisphere. Identifying Candidates for Corpus Callosotomy Referred to colloquially as split-brain surgery, corpus callosotomies are reserved for individuals grappling with the most severe and uncontrollable forms of epilepsy. Such cases typically involve relentless seizures affecting both cerebral hemispheres, and often occur in patients unresponsive to conventional antiseizure medications. Therefore, the procedure is recommended when other treatment avenues have proven futile. Preparations Before Corpus Callosotomy Before embarking on the surgical journey, potential candidates undergo an extensive pre-surgery evaluation. This in-depth assessment includes seizure monitoring, electroencephalography (EEG), magnetic resonance imaging (MRI), and positron emission tomography (PET) scans. These diagnostic tools enable medical professionals to precisely identify the point of seizure origination and map out the patterns of seizure propagation within the brain. Such critical information informs the decision-making process, ensuring the appropriateness of a corpus callosotomy. A Glimpse into the Surgical Procedure The corpus callosotomy itself is an intricate and highly delicate surgical endeavor. It necessitates the meticulous exposure of the brain through a procedure known as a craniotomy. Prior to the surgery, the patient is placed under anesthesia to ensure they remain unconscious and free from pain. Subsequently, an incision is made in the scalp, followed by the removal of a piece of bone and the retraction of the dura, the protective membrane encapsulating the brain. This procedure provides a clear “window” through which specialized instruments are inserted to disconnect the corpus callosum. With great care and precision, the surgeon gently separates the cerebral hemispheres to access and sever the corpus callosum. To aid in this delicate process, surgical microscopes are employed to provide a magnified view of the intricate brain structures. In certain scenarios, a corpus callosotomy is conducted in two stages. In the initial operation, the anterior two-thirds of the corpus callosum is severed, while the posterior section is preserved to enable the continued sharing of visual information between hemispheres. However, if this initial intervention fails to control the severe seizures, the remaining portion of the corpus callosum may be cut in a second surgical session. Once the corpus callosum is effectively severed, the dura and bone are securely repositioned, and the scalp is meticulously closed using either stitches or staples. Post-Operative Care and Recovery Following a corpus callosotomy, patients typically remain in the hospital for a period spanning two to four days. Subsequently, most individuals can resume their usual activities, including work or school, within six to eight weeks post-surgery. The hair surrounding the incision site eventually conceals the surgical scar, allowing for a semblance of normalcy. Patients will continue to take antiseizure medications as part of their ongoing treatment plan. Efficacy of Corpus Callosotomy A corpus callosotomy has proven to be highly effective in curtailing drop attacks or atonic seizures, characterized by sudden loss of muscle tone and resultant falls. In approximately 50% to 75% of cases, these seizures are successfully suppressed, thereby reducing the risk of injury and significantly enhancing the patient’s quality of life. Unveiling the Side Effects of Corpus Callosotomy Although corpus callosotomies are undeniably life-altering in their positive impact, they can give rise to certain side effects, albeit typically temporary in nature. These may include: 1. Scalp Numbness: Some patients may experience numbness in the scalp following the surgery. 2. Nausea: Post-surgery, feelings of nausea may be experienced. 3. Fatigue and Depression: A temporary sense of fatigue or emotional distress may occur in the wake of the procedure. 4. Headaches: Headaches are a potential side effect of the surgery. 5. Cognitive Impairments: Patients may encounter difficulties with speaking, memory, or word retrieval. 6. Motor Impairments: Corpus callosotomy can lead to paralysis, muscle weakness, or loss of sensation. 7. Personality Changes: Patients may exhibit alterations in personality characteristics following the procedure. Exploring the Risks Associated with Corpus Callosotomy While serious complications are relatively rare with corpus callosotomies, they are not without risks. These potential risks encompass: 1. Surgical Risks: Such as infection, bleeding, or adverse reactions to anesthesia. 2. Brain Swelling: An unfortunate outcome of the surgery can be swelling in the brain. 3. Hemispatial Neglect: Some patients may experience a lack of awareness on one side of their body. 4. Coordination Issues: Post-surgery, a loss of coordination may manifest. 5. Speech Problems: Stuttering or other speech issues can be a consequence of the procedure. 6. Partial Seizure Increase: On occasion, corpus callosotomy may lead to an increase in partial seizures confined to one side of the brain. 7. Stroke: There is a slight risk of stroke associated with the surgery, although it is relatively uncommon. In conclusion, corpus callosotomy, or split-brain surgery, stands as a remarkable medical intervention that can dramatically improve the quality of life for individuals with intractable epilepsy. Despite potential side effects and risks, the procedure’s effectiveness in mitigating seizures and preventing drop attacks underscores its importance in the field of neurosurgery. As medical science continues to advance, it is likely that corpus callosotomies will continue to evolve, offering new hope and improved outcomes for those suffering from this debilitating condition.

Sep 05

Signs and Symptoms of Alzheimer’s Disease

Alzheimer’s disease is a neurological condition that profoundly impacts cognitive functions such as memory, reasoning, and language. In the United States, over 6 million individuals aged 65 and above are affected by this disease. It’s important to distinguish between Alzheimer’s disease and the term “dementia.” While dementia is a broad term encompassing cognitive decline, including memory, thinking, and reasoning issues, Alzheimer’s specifically refers to a distinct disease. In the early stages of Alzheimer’s, individuals may encounter difficulties with memory, word retrieval, and occasional lapses in judgment. The disease typically progresses from mild (early-stage) to moderate and eventually severe (late-stage) Alzheimer’s. Symptoms The symptoms of Alzheimer’s disease primarily involve disruptions in cognitive functions. When diagnosing Alzheimer’s, healthcare professionals consider the following major categories of symptoms:4 In addition to these major symptom categories, individuals with Alzheimer’s may also experience the following: Early Warning Signs As you age, it’s normal to experience some memory changes. However, if you or those around you notice the following issues occurring more frequently, it’s important to consider speaking to a healthcare provider for a comprehensive evaluation:6 Mild (Early-Stage) Alzheimer’s Disease Symptoms During the early stage of Alzheimer’s disease, individuals often receive a diagnosis as symptoms become noticeable. In this mild stage, cognitive, behavioral, and personality changes begin to affect daily life on a frequent basis Cognition: Other cognitive issues may include difficulties with: Behavior: Individuals with mild Alzheimer’s may display the following behaviors: Personality: In the early stage of Alzheimer’s, individuals may experience new or intensified manifestations of: Moderate Alzheimer’s Disease Symptoms In moderate Alzheimer’s disease, the areas of the brain responsible for language, reasoning, thought processes, and sensory perception are further affected. Individuals at this stage require increased assistance and supervision. As the symptoms that were present in the early stage progress, new concerns arise. Cognitive, behavioral, and psychological changes become more pronounced, including difficulties in: Additionally, individuals may experience physical symptoms, including: Severe (Late-Stage) Alzheimer’s Disease Symptoms In the late stage of Alzheimer’s disease, significant changes occur in the brain, resulting in physical shrinkage of brain tissue. Individuals with severe Alzheimer’s are typically unable to communicate effectively and require full assistance with their daily care. They experience a wide range of physical concerns and rely entirely on their caregivers. They are often bedridden or spend most of their time in bed. At this stage, individuals with late-stage Alzheimer’s may struggle or be unable to perform the following tasks: In addition to the cognitive and functional challenges, individuals in the late stage of Alzheimer’s may also experience various physical issues, including: When to See a Healthcare Provider If you are experiencing memory or cognitive issues that are interfering with your daily life, it is important to seek guidance from a healthcare provider. Additionally, if people around you have noticed changes in your mood, personality, or ability to complete tasks, it is worth considering a conversation with a healthcare professional. To begin, you can schedule an appointment with a primary care doctor who can assess your condition and provide initial guidance. Depending on their evaluation, they may refer you to a neurologist, who specializes in brain and spinal cord conditions, or a geriatrician, who specializes in aging and care for older adults. A neuropsychologist can conduct memory and cognitive assessments, while a geriatric psychiatrist can evaluate any emotional difficulties you may be experiencing. Seeking medical attention as soon as you or others observe changes in your cognitive abilities can lead to earlier and more effective Alzheimer’s treatment. It is also possible that the symptoms may be caused by another treatable or curable condition, such as vitamin D deficiency or medication side effects. Remember, consulting with a healthcare provider will help provide a proper evaluation, diagnosis, and appropriate care for your specific situation. Rapid recap While occasional memory or cognitive issues are common with aging, Alzheimer’s disease leads to dementia and significant cognitive loss that interferes with daily life. Initially, Alzheimer’s affects cognition, personality, and behavior, eventually progressing to difficulties with basic tasks and a loss of communication and self-care abilities. If you or those around you notice changes in thinking, personality, or mood, it is important to seek advice from a healthcare provider. This can include a primary care doctor, neurologist, or geriatrician, who can help rule out other potential causes and initiate early Alzheimer’s treatment and planning as necessary. Taking action and seeking professional guidance can lead to appropriate support and care.

Sep 05

How Is Alzheimer’s Disease Diagnosed?

Alzheimer’s disease (AD) is a progressive neurological condition that leads to a significant decline in cognitive abilities, including memory, thinking, and judgment. Early detection is crucial for effective symptom management and improved quality of life. AD is most prevalent among individuals aged 65 and older and is distinguishable from normal age-related memory changes. Unlike typical memory changes, AD symptoms disrupt daily life and impair independent functioning. Diagnosing AD involves a comprehensive assessment using multiple tests, as there is no single diagnostic tool available. If you observe changes in your own memory or notice symptoms of AD in a loved one or caregiver, it is advisable to seek medical attention promptly. During the appointment, the healthcare provider will conduct a thorough medical history review, physical examination, psychiatric evaluation, and may order additional tests such as neurological exams, blood tests, and imaging scans. Undergoing testing for AD can be intimidating, and it is normal to feel apprehensive. If you are experiencing memory changes, having a loved one accompany you to the appointment can provide support. Similarly, if you believe a loved one requires testing, gently encouraging them to bring a trusted companion can be beneficial. Having support during the appointment aids in creating a comfortable environment and facilitates the provider’s understanding of recent changes in cognition and behavior reported by others. Medical History Obtaining a comprehensive medical history is an essential part of the evaluation process conducted by healthcare providers. During your initial appointment, your provider may inquire about the following aspects:45 During the appointment, healthcare providers may also request to interview a loved one to gather their perspective on any cognitive, behavioral, or psychological changes they have noticed before proceeding with additional tests. Cognitive and Neurological Exams Cognitive and neurological exams are essential in detecting changes in memory, thinking, and behavior. These tests provide valuable insights into an individual’s cognitive abilities and are typically conducted by neurologists, psychiatrists, or psychologists. The exams can be comprehensive and may require multiple sessions or several hours to complete. The primary goal is to assess various brain functions using a range of tests. Some of the functions that may be evaluated include: To examine these functions, healthcare providers may employ different types of exams, such as: Spinal Tap A spinal tap, also known as a lumbar puncture, is a procedure used to collect a small sample of cerebrospinal fluid (CSF) for analysis. CSF is a fluid that surrounds the brain and spinal cord and can provide valuable information about various neurological conditions, including Alzheimer’s disease (AD). During a spinal tap, a healthcare provider inserts a needle into the lower back to access the spinal canal and collect a sample of CSF. In the case of AD, specific proteins in the CSF, known as biomarkers, can indicate the presence or progression of the disease. Abnormal levels of these biomarkers, such as amyloid-beta and tau proteins, can help support an AD diagnosis. However, it’s important to note that CSF biomarker analysis is not a definitive diagnostic test for AD and is often used in combination with other assessments. Ongoing research in the field aims to explore alternative methods for detecting biomarkers associated with AD. One area of focus is the development of blood-based biomarkers, which would be easier and less invasive to obtain than CSF samples. In May 2022, the U.S. Food and Drug Administration (FDA) approved a new CSF test for AD, indicating ongoing advancements in diagnostic techniques. It’s important to be aware that not all hospitals offer spinal tap exams, and the availability and coverage may vary depending on your healthcare insurance. If you and your healthcare provider believe that a spinal tap may be beneficial in your case, it is advisable to discuss the procedure with your provider and insurance company to determine feasibility and coverage options. Brain Imaging There are additional exams and measures that healthcare providers may utilize, each with its own scoring guidelines and criteria. The results of these exams contribute to determining the subsequent steps and appropriate diagnosis or treatment plan for you or your loved one. Brain imaging tests and lab tests play an important role in the diagnostic process for Alzheimer’s disease (AD) by providing additional information and ruling out other conditions. The main types of brain imaging tests include: It is important to note that imaging tests alone cannot diagnose AD, but they can help rule out other conditions and provide insights into the brain’s structure. Therefore, they are often used in combination with cognitive exams. Lab Tests While blood and urine tests cannot directly diagnose AD, they can help identify related conditions that may be causing symptoms. These tests can check for infections, vitamin deficiencies, and other underlying conditions that may contribute to cognitive impairment. Screening for Related Conditions Screening for related conditions is also an important part of the diagnostic process. Symptoms of AD can overlap with other conditions, and healthcare providers will often screen for these conditions to rule them out. Some of the conditions or situations that can cause similar symptoms to AD include: If a provider suspects a different condition may be responsible for the symptoms, they may order additional tests or refer you or your loved one to a specialist for further evaluation and treatment.

Sep 05

9 Surprising Memory Loss Causes Later in Life

Genetics and aging are significant factors that contribute to memory loss and dementia, which refers to the decline in cognitive functions such as thinking, remembering, and reasoning, as highlighted by the National Institute on Aging (NIA). It is estimated that around one-third of individuals aged 85 and older may experience dementia, underscoring the importance of recognizing early signs and risk factors associated with the condition. While Alzheimer’s disease is the primary cause of dementia, there are other conditions that can also lead to memory and cognitive impairments. Although the exact causes of cognitive issues are not fully understood, researchers have identified several factors that are associated with an increased risk of dementia. Interestingly, some of these factors, such as depression, can both contribute to the development of dementia and serve as potential indicators of the condition. Therefore, it is crucial to be vigilant and address these risk factors and signs early on for optimal management and support. Poor Sleep Poor sleep has various detrimental effects on the brain, and prolonged sleep disturbances may contribute to processes that increase the risk of Alzheimer’s disease. In addition to Alzheimer’s, other sleep-related issues such as insomnia, sleep apnea, inadequate sleep duration (less than 5 hours or more than 10 hours per night), and overall poor sleep quality have also been associated with an increased risk of dementia, as stated in an August 2018 publication in Sleep Medicine Reviews. Interestingly, Alzheimer’s disease itself can further disrupt sleep patterns, exacerbating symptoms of the condition. A July 2020 report published in Lancet Commissions highlights the bidirectional relationship between Alzheimer’s and sleep disturbances, indicating that disrupted sleep can negatively impact the symptoms and progression of the disease. Taken together, these findings underscore the crucial role of sleep in brain health and emphasize the importance of addressing sleep issues as a potential risk factor and target for intervention in preventing or managing dementia and Alzheimer’s disease. Loneliness Social isolation has been identified as a potential contributor to the decline of certain cognitive functions, including memory. On the other hand, engaging in social activities and having larger social networks in later life have been associated with better cognitive functioning, as noted in an August 2019 review published in the Journal of Alzheimer’s Disease. It is important to consider that social isolation may not necessarily cause dementia, but could be an early symptom of the condition. The March 2021 review published in Alzheimer’s & Dementia suggests that individuals experiencing memory loss may withdraw from social interactions due to challenges in participating in hobbies or keeping up with their interests, potentially leading to social isolation. These findings highlight the potential protective effects of socializing and maintaining social connections in maintaining cognitive health. While the relationship between social isolation and dementia is complex and may involve bidirectional influences, prioritizing social engagement and maintaining social networks may contribute positively to cognitive well-being. Head Injuries Head injuries, or traumatic brain injuries (TBIs), have been associated with an increased risk of dementia, as highlighted in the March 2021 review. This risk is particularly elevated in individuals who have experienced multiple TBIs or a severe TBI, as indicated by an April 2018 study published in Lancet Psychiatry. The exact mechanisms underlying the link between head injuries and dementia are not fully understood and may vary depending on the severity of the injury, as suggested by a September 2018 study published in JAMA Neurology. Further research is needed to better comprehend the specific reasons why head injuries contribute to the development of dementia. It is important to prioritize prevention and proper management of head injuries, seeking medical attention and following appropriate protocols for evaluation and treatment. Taking steps to minimize the risk of head injuries, particularly repeated or severe ones, can potentially help reduce the associated risk of developing dementia. Air Pollution Exposure to air pollutants, as indicated by the August 2019 review in the Journal of Alzheimer’s Disease, has been associated with an increased risk of dementia. Specifically, high levels of PM2.5 (particulate matter) and NO2/NOx (harmful gases) in the air can lead to brain inflammation. PM2.5 refers to tiny particles in the air that can originate from various sources including power plants, construction sites, and fires, according to the United States Environmental Protection Agency (EPA). On the other hand, NO2/NOx are gases emitted from burning fuel in vehicles and power plants, also per the EPA. Exposure to high levels of NO2 can result in respiratory issues such as asthma, as highlighted by the EPA. Furthermore, PM2.5 air pollution has been linked to various health problems, including heart disease, kidney disease, high blood pressure, and type 2 diabetes, as stated in a November 2019 study published in the journal JAMA Network Open. Reducing exposure to air pollutants, such as through improved air quality regulations, minimizing personal exposure in polluted areas, and using air filtration systems, may play a role in mitigating the associated health risks, including the potential impact on dementia. Heavy Alcohol Use and Smoking Heavy alcohol use, as noted in the July 2020 report, can lead to changes in brain structures that may contribute to cognitive issues. Drinking more than 21 units of alcohol per week (equivalent to about two bottles of wine) can increase the risk of cognitive decline. However, there is no evidence to suggest that light or moderate drinking has detrimental effects on cognitive functioning later in life. A review published in January 2019 in the journal Alzheimer’s Research & Therapy proposed that reducing alcohol consumption could be a strategy for preventing dementia, although further research is needed to establish a definitive link. It is generally recommended to limit alcohol intake to about 14 units per week (equivalent to approximately 6 pints of average-strength beer), spread out over multiple days. Smoking is also associated with an increased risk of dementia. However, quitting smoking has been shown to potentially reduce this risk, as indicated by a September 2018 study published in the journal Annals of Clinical and Translational Neurology. Quitting smoking

Sep 05

What is Cerebellar Agenesis?

Causes and symptomsEpidemiologyCase reportDiagnosis and treatmentReferencesFurther reading Cerebellar agenesis is a condition in which the normal formation of the hindbrain is disrupted. Patients with this disorder have very few pieces of cerebellar tissue – frequently the remains of lower cerebellar peduncles, anterior vermal lobules, and flocculi. Cerebellar agenesis is a condition in which the normal formation of the hindbrain is disrupted. Image Credit: Peter Porrini/Shutterstock.com Both genetically mediated and disruptive causes can cause cerebellar agenesis (CA). Cerebellar agenesis can manifest itself in various ways, with symptoms ranging from mild to severe. Cerebellar agenesis affects not only physical abilities but also cognitive abilities, linguistic impairments, and affective issues. Causes and symptoms Cerebellar agenesis is caused by a variety of factors (heterogeneous). Cerebellar damage caused by bleeding, lack of or decreased blood flow (ischemia), or other conditions are acquired (prenatal/perinatal) causes. Cerebellar agenesis (CA) can be caused by both genetically mediated and disruptive causes. CA can be caused by a genetically mediated pathomechanism (e.g., mutations in the pancreatic transcription factor 1 gene, PTF1) or a disruption (e.g., intrauterine/neonatal damage with the disappearance of the developing cerebellum). Sener used the phrase “vanishing cerebellum” to describe cerebellar disruptive lesions in children with Chiari II malformation. Prenatal hindbrain herniation through the foramen magnum can induce parenchymal injury, resulting in the resolution of a portion of the cerebellum (usually asymmetric). The cerebellum vanishes totally in disruptive CA due to direct or indirect damage. Cerebellar agenesis can manifest itself in various ways, depending on the person. According to the medical literature, some people with cerebellar agenesis have only modest symptoms. It has been suggested that motor performance may be nearly normal in some cases, possibly due to partial compensation from other brain areas. Individuals with cerebellar agenesis whose mental capacities were undamaged and who did not exhibit any symptoms of cerebellar agenesis have also been reported (asymptomatic cases). Cerebellar agenesis most likely represents a spectrum of diseases ranging from severe disability to milder manifestations of the disorder. Earliness, localization, and degree of cerebellar agenesis appear to be linked to the severity and range of motor, cognitive, and psychiatric deficits. Patients with congenital anomalies have more severe and less specific impairments than those who develop cerebellar lesions later in life. Patients with phylogenetically more ancient structures involved (complete or partial cerebellar vermis agenesis) have a more severe clinical picture. This includes severe, pervasive impairments in social and communication skills (autism or autism-like behavior), behavior modulation (self-injury and aggressiveness), and a marked delay in language acquisition, especially in language comprehension. Related Stories When lesions are limited to phylogenetically more recent structures, such as the cerebellar hemispheres, the clinical picture is marked by minor cognitive impairment or borderline IQ, adequate social functioning, context adjustment abilities, and a better prognosis. Epidemiology Cerebellar agenesis is extremely uncommon, with only a few documented cases. CA appears to afflict both men and women in about equal percentages. The disorder’s exact frequency and prevalence in the general population are unknown. The occurrence of congenital solitary cerebellar agenesis is extremely unusual. Case report In 2020, Dennison et al. described a case of cerebellar agenesis recently encountered and diagnosed in Orlando, Florida, United States. At 37 weeks and two days, a 25-year-old mother gave birth to a 5 lb 11 oz, somewhat preterm child via C-section. Polyhydramniosis and a positive chlamydia test during early pregnancy affected the pregnancy, which later tested negative after therapy. The fetus was breech at birth, necessitating a cesarean section. The amniotic fluid was stained with meconium, and the umbilical cord was found to be short. The infant was microcephalic, hypertonic, and spastic at birth and was in significant respiratory distress with irregular breathing. At one and five minutes after birth, the APGAR scores were 5/10 and 7/10, respectively. The infant’s breathing problems persisted, necessitating an emergency transfer to the newborn intensive care unit (NICU), where they were put on continuous positive airway pressure (CPAP). The infant was hypertonic and had excessive deep tendon reflexes, according to a medical assessment performed in the NICU. All primitive reflexes were missing, including Moro, rooting, and sucking. A systolic cardiac murmur of grade I to II was also present in the baby. Bilaterally, coarse breath sounds were heard. The infant had twitching and spastic motions during their time in the NICU. The infant had echocardiography on day one of life, which revealed a massive, bidirectional patent ductus arteriosus. A patent foramen ovale with left-to-right shunting was also present. Because of the aberrant neurological test, a brain computed tomography was performed, which revealed that the cerebellum was almost completely absent, with only traces of the cerebellar hemispheres and vermis remaining. There was also partial corpus callosum agenesis and extensive cerebral and brain stem atrophy. Brain magnetic resonance imaging (MRI) verified these results, prompting additional neurological testing. During waking and sleep, continuous electroencephalography indicated significantly aberrant background activity with burst suppression and extended clusters of infantile spasms, consistent with early infantile epileptic encephalopathy (also known as Ohtahara syndrome). Topiramate was prescribed for the infant’s epileptic activity, considerably reducing symptoms. The infant had a tracheostomy and a gastrostomy tube before being discharged. The infant’s spasms persisted despite a visit to the neurology department, although they showed modest improvement following a course of high-dose steroids. To date, follow-up electroencephalography has revealed that epileptiform discharges have persisted. The infant’s spastic quadriplegia remained severe, necessitating a ventilator and g-tube. The infant experienced sudden cardiac arrest at six months of age and was brought to a hospital after multiple rounds of cardiopulmonary resuscitation and recovery of spontaneous circulation. The infant was eventually declared brain dead, and life support was turned off. Diagnosis and treatment Diagnosis is largely based on the neuroimaging findings of MRI. Regarding diagnosis, prognosis, and genetic counseling, it is also critical to distinguish cerebellar disturbances from cerebellar abnormalities. The treatment for cerebellar agenesis focuses on the specific symptoms that each person experiences. Collaboration with a group of professionals might be necessary for treatment. Pediatricians, neurologists, speech pathologists, and other