Neuroanatomy
Dr Raymond Chang
Subtitles in English for this video can be displayed by clicking on (first button on the bottom right hand corner of the video). Stereopsis (three dimensional vision) is important in our every day lives. This ability is dependent on aligning both foveae on the same object with slightly dissimilar perspectives to give a perception of depth….
In the first video, the patient has both horizontal nystagmus and vertical “down-beat” nystagmus. In the second video, the patient has a torsional nystagmus when looking to her right hand side. Discussion of the sign Nystagmus is defined as a rhythmic oscillation of the eyes. It usually consists of a slow drifting phase in one direction and a…
As one can appreciate in this video, this middle-aged man has right-sided intention tremor. The right index finger shows exaggerated tremor when approaching the target, i.e. his nose and physician’s finger. Please note that the examiner should place his finger at around one arm’s length from the patient. This is so that the patient could…
Intention tremor can be elicited by the finger-nose test. In normal patients, the movements between the physician’s finger and patient’s nose should be smooth, but adjustment is allowed according to the patient’s upper limb power. This man has intention tremor and impaired finger-nose test on the right side, whilst the left side is normal. Discussion on intention…
Bilateral watershed infarct The non-contrast CT brain shown is from a patient with bilateral watershed infarct. Here, chronic ischaemic changes can be seen along the external or cortical watershed zones (Figures 1 and 2). These “borderzones” is where the terminal vasculature of the anterior cerebral artery and middle cerebral artery meet as well as where the middle…
Subtitles in English for this video can be displayed by clicking on (first button on the bottom right hand corner of the video). The size of the pupillary aperture at any point in time is dependent on a balance between sympathetic tone, parasympathetic tone, the light reflex and the near reflex. The light reflex is an…