An Approach to the Examination of the Lumbar Plexus for Neurosurgical Residents: A Video Manuscript.

The lumbar plexus provides innervation to the lower limbs and is essential in enabling motor movement and sensation in the lower limbs. Some of its branches also innervate the muscles in the pelvic girdle. Compared to the brachial plexus in the upper limbs, the lumbar plexus appears to garner less recognition among physicians and surgeons. However, it is important to understand the anatomy of the lumbar plexus and its branches along with the innervation they enable, as injury to them can cause plexopathies and pathologies that should be recognised by any treating clinician. Lumbar disc herniation, trauma and entrapment by muscles or hypertrophic ligaments are common causes of lumbar plexus or nerve injuries. A video was produced to demonstrate the examination techniques explained in this article. To provide comprehensive examination of the lower limbs, the sciatic nerve and its branches are also included in the examination video.

A case of cerebral toxoplasmosis: "Eccentric and concentric sign" in MRI.

Central nervous system (CNS) toxoplasmosis is an opportunistic infection caused by the intracellular protozoan parasite Toxoplasma gondii. This organism typically causes disease in immunocompromised patients with human immunodeficiency virus (HIV). We reported a case of a 52-year-old woman with neurology symptoms and Magnetic resonance imaging (MRI) brain shows both eccentric and concentric target signs, which are typical signs in a patient with cerebral toxoplasmosis but rarely displayed in the same lesion. The MRI played a crucial role in diagnosing the patient and distinguishing CNS diseases commonly found in HIV patients. Our objective is to discuss the imaging findings that aided in the patient's diagnosis.

Dorsal Column Bedside Examination Test: Tips for the Neurosurgical Resident.

The dorsal column medial lemniscus (DCML) system is a sensory pathway of the central nervous system; it carries sensations of soft touch, vibration, proprioception, two-point discrimination, and pressure from the skin and joints. The clinical signs of the DCML pathway lesions include loss of soft touch, vibratory sense, proprioception, discrimination sense, and a positive Rhomberg test. Diseases that affect this pathway are usually degenerative, for example, spinal cord degeneration due to vitamin B12 deficiency; it can also be affected by trauma or infarction of the posterior spinal artery causing posterior cord syndrome. This video manuscript provides a step-by-step examination technique of the dorsal column examination, specially catered for Malaysian medical students and trainees. A series of videos show the techniques for soft touch sensation examination, examination of the vibratory sense, examination of the joint position sense, examination of two-point discrimination and the Rhomberg test. We hope that students can adhere to these techniques and apply them in their daily neurological assessments.

Motion characteristics of subclinical tremors in Parkinson's disease and normal subjects.

The characteristics of the Parkinson's disease tremor reported previously are not applicable to the full spectrum of severity. The characteristics of high- and low-amplitude tremors differ in signal regularity and frequency dispersion, a phenomenon that indicates characterisation should be studied separately based on the severity. The subclinical tremor of Parkinson's disease is close to physiological tremor in terms of amplitude and frequency, and their distinctive features are still undetermined. We aimed to determine joint motion characteristics that are unique to subclinical Parkinson's disease tremors. The tremors were characterised by four hand-arm motions based on displacement and peak frequencies. The rest and postural tremors of 63 patients with Parkinson's disease and 62 normal subjects were measured with inertial sensors. The baseline was established from normal tremors, and the joint motions were compared within and between the two subject groups. Displacement analysis showed that pronation-supination and wrist abduction-adduction are the most and least predominant tremor motions for both Parkinson's disease and normal tremors, respectively. However, the subclinical Parkinson's disease tremor has significant greater amplitude and peak frequency in specific predominant motions compared with the normal tremor. The flexion-extension of normal postural tremor increases in frequency from the proximal to distal segment, a phenomenon that is explainable by mechanical oscillation. This characteristic is also observed in patients with Parkinson's disease but with amplification in wrist and elbow joints. The contributed distinctive characteristics of subclinical tremors provide clues on the physiological manifestation that is a result of the neuromuscular mechanism of Parkinson's disease.

Deep Tendon Reflex: The Tools and Techniques. What Surgical Neurology Residents Should Know.

The deep tendon reflex (DTR) is a key component of the neurological examination. However, interpretation of the results is a challenge since there is a lack of knowledge on the important features of reflex responses such as the amount of hammer force, the strength of contraction, duration of the contraction and relaxation. The tools used to elicit the reflexes also play a role in the quality of the reflex contraction. Furthermore, improper execution techniques during the DTR assessment may alter the findings and cloud the true assessment of the nervous system. Therefore, understanding the basic principles and the key features of DTR allows for better interpretation of the reflex responses. This paper discusses the brief history of reflexes, the development of the reflex hammer, and also the key features of a reflex response encompassing the amplitude of force needed to elicit a reflex response, the velocity of contraction, the strength of contraction, and the duration of contraction and relaxation phases. The final section encloses the techniques of eliciting DTR in the upper extremities, trunk, and lower extremities, and the interpretation of these reflexes.

Seizures among young adults consuming kratom beverages in Malaysia: A case series.

We report a case series of young adults who were admitted to hospital with seizures after regular kratom beverage consumption. This study aimed to determine kratom consumption habits and seizure characteristics and to explore whether chronic kratom ingestion without concomitant drug abuse leads to recurrent seizure or epilepsy. All patients underwent blood investigations, a brain computed tomography (CT) scan, electroencephalography, and urine testing for mitragynine and drug toxicology. Eleven participants who had a positive urine mitragynine test were included in the study. The longest duration of kratom consumption was 84 months: - most drank more than eight times per month (>200 mL/drink). Seizure developed within 10 minutes or up to 72 hours post-ingestion. Seizure occurred one to three times per year in most cases. Four patients had a focal to bilateral tonic-clonic seizure whereas the remaining participants had a generalized tonic-clonic seizure. Four patients mixed kratom with diphenhydramine syrup, and one patient took methamphetamine. Two patients had positive urine results for recreational drugs (opioid and amphetamine). This study provided indirect evidence that chronic kratom use with or without concomitant drug abuse can cause recurrent seizures in susceptible individuals, which may progress to epilepsy or require antiepileptic medication.

Disconnecting surgery at alveus and cornu ammonis of hippocampus, amygdala superficialis, and amygdala medial nuclei for epilepsy associated with attention deficit hyperactivity disorder.

The neural basis for epilepsy and attention deficit hyperactivity disorder (ADHD) is currently incompletely known. We reported a young girl with both epilepsy and ADHD, who had a calcified lesion in the right basolateral amygdalo-hippocampal region extending to the ventral striatum. The child underwent disconnecting surgery and biopsy of the lesion. Fascinatingly, the child's behavior changed immediately after the surgery from inattentive and impulsive to nearly normal behavior experiencing no more breakthrough seizures since after 3 years of surgery. The Schaltenbrand Wahren Brain Atlas revealed alveus, cornu ammonis, amygdala superficialis, and medium as the disconnected region in this surgery.

Examination Techniques of the First Cranial Nerve: What Neurosurgical Residents Should Know.

Olfactory or smell dysfunction is often overlooked by clinicians despite being prevalent in the population. To date in Malaysia, there is no standard and reliable test to examine the function of olfaction. Tests used at developed countries such as the Sniffin' Sticks Test (SST), the Connecticut Chemosensory Clinical Research Center (CCCRC) test, the University of Pennsylvania Smell Identification Test (UPSIT) and the Brief Smell Identification Test (B-SIT) are not readily available in this region and may be costly to procure. The first cranial nerve can be tested using commonly available materials to assess: i) the function of odour detection; ii) the odour discrimination; and iii) the odour identification. An abnormal odour detection threshold test generally indicates a peripheral olfactory problem while the odour discrimination and identification test attribute the problem to the cerebral cortex. An olfactory complaint should not be taken lightly and a proper olfactory function examination is important: i) to determine the legitimacy of a patient's complaint; ii) to monitor the progress of patient's olfactory function; iii) to establish insurance payout for disability; and iv) to characterise the specific nature of the problem. A video has been produced to demonstrate the examination techniques explained in this article.

The Neurological Exam of a Comatose Patient: An Essential Practical Guide.

A thorough examination of a comatose patient is essential given the spectrum of clinical diagnoses. The most immediate threat to patients is airway, breathing and circulation. All attending physician should employ a structured and focused approach in dealing with a comatose patient. It is important to recognise the urgent steps needed at the time to prevent further deterioration, followed by the final diagnosis of patient's neurologic status. Here we provide the essential practical guide to the neurological exam of a comatose patient that would assist to determine the aetiology, location and nature of the neurological lesion.

An In-Laboratory Validity and Reliability Tested System for Quantifying Hand-Arm Tremor in Motions.

Despite the advancement of the tremor assessment systems, the current technology still lacks a method that can objectively characterize tremors in relative segmental movements. This paper presents a measurement system, which quantifies multi-degrees-of-freedom coupled relative motions of hand-arm tremor, in terms of joint angular displacement. In-laboratory validity and reliability tests of the system algorithm to provide joint angular displacement was carried out by using the two-degrees-of-freedom tremor simulator with incremental rotary encoder systems installed. The statistical analyses show that the developed system has high validity results and comparable reliability performances using the rotary encoder system as the reference. In the clinical trials, the system was tested on 38 Parkinson's disease patients. The system readings were correlated with the observational tremor ratings of six trained medical doctors. The moderate to very high clinical correlations of the system readings in measuring rest, postural and task-specific tremors add merits to the degree of readiness of the developed tremor measurement system in a routine clinical setting and/or intervention trial for tremor amelioration.

Deep Brain Stimulation (DBS) for Movement Disorders: An Experience in Hospital Universiti Sains Malaysia (HUSM) Involving 12 Patients.

Deep brain stimulation (DBS) was first introduced in 1987 to the developed world. As a developing country Malaysia begun its movement disorder program by doing ablation therapy using the Radionics system. Hospital Universiti Sains Malaysia a rural based teaching hospital had to take into consideration both health economics and outcomes in the area that it was providing neurosurgical care for when it initiated its Deep Brain Stimulation program. Most of the patients were from the low to medium social economic groups and could not afford payment for a DBS implant. We concentrated our DBS services to Parkinson's disease, Tourette's Syndrome and dystonia patients who had exhausted medical therapy. The case series of these patients and their follow-up are presented in this brief communication.

Epilepsy Surgery in Hospital Universiti Sains Malaysia: Our Experiences since 2004.

Epilepsy surgery has been performed by a few centres in Malaysia, including Hospital Universiti Sains Malaysia (HUSM). To date, a total of 15 patients have undergone epilepsy surgery in HUSM. The epilepsy surgery included anterior temporal lobectomy (ATL) with amygdalohippocampectomy (AH) and Vagal nerve stimulation (VNS). The surgical outcomes of the patients were assessed using the International League Against Epilepsy (ILAE) outcome scale. The ILAE scores for patients who underwent ATL with AH were comparatively better than those who underwent VNS. One of the patient who underwent ATL with AH and frontal lesionectomy was found to have psychosis during follow up. Epilepsy surgery has proven to be an important treatment for medically resistant epilepsy. Thus it is important to raise public awareness regarding epilepsy and its treatment.