Nevrologisk undersøkelse - Amboss Flashcards

Question

Hvordan tester man fargesynet?

Answer 1

Pupillerefleks Bevegelse av øynene Visuell akkomodasjon: - Akkommodasjon er en prosess som øker lysbrytingen i øyet og dermed gjør det mulig å lese liten skrift og se enda mindre objekter klart på nært hold. Øyelokks ptose: - M.levator palpebrae superior dysfunksjon

Answer 2

**Pupillary light reflex** The afferent pathway (blue tract) is initiated when light hits the retina: - Retinal photoreceptors → ipsilateral optic nerve → nuclei of bilateral pretectal areas (nasal fibers of the optic nerve cross to the contralateral side at the optic chiasma) The efferent pathway (green tract) transmits neural impulses to the iris sphincter muscle: - Nuclei of pretectal area → bilateral Edinger Westphal nuclei (parasympathetic preganglionic nucleus of the oculomotor nerve) → bilateral oculomotor nerves (synapse at the ciliary ganglion) → bilateral iris sphincter muscle (and ciliary muscle) → bilateral pupillary constriction (and accomodation). Shining a light into one eye causes constriction of the ipsilateral pupil (direct pupillary reflex) as well as that of the contralateral pupil (indirect or consensual pupillary reflex).

Answer 3

**Characterization of nystagmus by direction** In jerk nystagmus, there is a slow drift phase followed by a fast corrective phase. The name of the nystagmus is determined by the direction of movement in the fast phase (left horizontal, right horizontal, downbeat, upbeat, clockwise, or counterclockwise).

Answer 4

**Clinical testing of the extraocular muscles** A quick clinical examination of extraocular muscle function can be performed by asking the patient to follow the examiner's finger with the eyes while keeping the head immobile. Tracing the letter “H” in the air (dark grey arrows) will prompt the patient to move through the 6 cardinal positions of gaze. In these positions, a single muscle is the primary mover for each eye. Some examiners find it beneficial to return to the center between each cardinal position, drawing a star shape (dark grey horizontal arrow plus light grey arrows), while others combine the complete “H” and diagonal movements. Note that for all muscles except the lateral- and medial recti, the directions in which these muscles are tested clinically (shown here) differ from the direction they would move the eyeball if acting in isolation. The difference arises because eye movements are the result of complex interactions between several extraocular muscles. Therefore, the movement used to test a particular muscle clinically is the movement that most effectively excludes the participation of other muscles. For example, while the superior oblique (SO) depresses and abducts the eye when acting in isolation, depression is also produced by the inferior rectus (IR), and abduction is also produced by the lateral rectus (LR). However, due to their different points of insertion, the IR is the more efficient depressor of the eye in abduction, while the SO is the more efficient depressor in adduction. Looking down and inwards, therefore, allows the isolated clinical examination of the SO (as shown here). Similar principles apply to the movements used for clinical testing of the IR, SR, and IO.

Answer 5

Følesanser i ansiktet Muskelfunksjon

Answer 6

Motorfunksjon: - Ansiktets mimiske uttrykk Smakssans

Answer 7

**Examination findings in facial nerve palsy** Symptoms in central facial palsy are caused by a contralateral upper motor neuron (UMN) lesion. Because muscles responsible for eyelid and forehead movements are innervated by upper motor neuron fibers from both hemispheres, their function is preserved in central facial palsy. In peripheral facial palsy, damage to lower motor neuron (LMN) fibers results in ipsilateral paralysis of all facial muscles. Because sensory and autonomic fibers join the lower motor neuron fibers of the facial nerve in its peripheral course, peripheral facial palsies can also manifest with non-motoric symptoms.

Answer 8

**Hørselstest** **Vestibulocochlear refleks:** A brainstem reflex elicited by activating the vestibular system (e.g., via head movement or caloric stimulation). Normally, the eyes move in the opposite direction to the head movement/caloric stimulation with warm water to stabilize the image in the center of the visual field. The reflex is mediated by the afferent sensory pathway of CN VIII and the efferent motor pathway of the contralateral CN VI and the ipsilateral CN III. **Balansetester** | VIII

Answer 9

**Head impulse test:** A maneuver to examine the vestibuloocular reflex and clinically differentiate between peripheral and central causes of acute vestibular syndrome. Considered abnormal if the patient is unable to maintain central visual fixation, in which case a corrective saccade (quick eye movement) occurs to fixate on the target again. This indicates a deficient vestibuloocular reflex on the side of the head turn.

Answer 10

**Fasciculation** A twitching of muscle caused by involuntary, asynchronous contraction of muscle fascicles within a single motor unit (i.e., all fascicles supplied by a single motor neuron). Usually benign but can signify a lower motor neuron lesion when accompanied by other motor deficits.

Answer 11

**Spasticity** A physical finding of increased, involuntary, velocity-dependent muscle tone, which causes stiffness, and/or tightness of the muscles and manifests as resistance to movement. Occurs following damage to the primary motor cortex or the corticospinal tract (e.g., stroke, neurodegenerative disease, cerebral palsy). **Clonus** A series of rapid, rhythmic, involuntary muscular contractions. ## Footnote [https://www.youtube.com/watch?v=J3cGY58x5JM](http://)

Answer 12

Hvile Intensjon Postural

Answer 13

## Footnote [https://www.youtube.com/watch?v=2MkNKTXp7L8](http://)

Answer 14

## Footnote [https://www.youtube.com/watch?v=P98BISwkuw0](http://) [https://www.youtube.com/watch?v=nvOYn5uZWwM](http://)

Answer 15

## Footnote [https://www.youtube.com/watch?v=t89lKK52zLo](http://)

Answer 16

## Footnote [https://www.youtube.com/watch?v=Ll8r5i0eaT8&t=28s](http://)

Answer 17

## Footnote [https://www.youtube.com/watch?v=NTQcbhoeJ1Q](http://) [https://www.youtube.com/watch?v=R7NBn0aG6AA](http://)

Answer 18

**Stretch reflex** Striking the patellar tendon results in two reflexes that occur simultaneously: (a) Monosynaptic reflex: Stretching of the patellar tendon is detected by muscle spindles in the quadriceps femoris muscle. An impulse is passed to the spinal cord via somatic afferent (Ia) fibers of pseudounipolar neurons, the somata of which are located in the dorsal root ganglion. In the anterior horn, the afferent neurons synapse directly with α motor neurons that innervate the same muscle and thus cause contraction. (b) Polysynaptic reflex: The afferent neurons synapse with inhibitory interneurons in a different segment of the spinal cord. These interneurons then inhibit the α motor neurons of the antagonistic muscle.

Nevrologisk undersøkelse - Amboss Flashcards

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