Neuroanatomy
Dr Raymond Chang
Similar Posts
Osmotic Demyelination Syndrome
This is a set of cranial MRIs from a patient with osmotic demyelination syndrome, formerly called central pontine myelinolysis. Osmotic demyelination syndrome occurs when wide fluxes in serum sodium levels are induced by too rapid correction of hyponatremia. Oligodendrocytes, which forms the myelin sheaths, are particularly vulnerable to osmotic changes. If the osmotic stress is…
Ischaemic Changes of Different Anatomical Regions or Vascular Territories
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…
Sixth Nerve Palsy
In this patient, there is a mild esotropia on neutral gaze as the left eye is slightly deviated medially. There is impaired left eye abduction resulting in diplopia when the patient is instructed to look towards the left. Discussion of the sign Abduction of the eye is controlled by the lateral rectus muscle, which is…
Ocular Alignment and Extra-ocular Movement Examination
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….
Horizontal Nystagmus
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…
Intention Tremor
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…
