[vc_row row_type=”row” use_row_as_full_screen_section=”no” type=”full_width” oblique_section=”no” text_align=”left” css_animation=””][vc_column][ultimate_heading main_heading=”Candidate brief” main_heading_color=”#000000″ sub_heading_color=”#000000″ main_heading_style=”font-weight:bold;” main_heading_font_size=”desktop:36px;”]

“This patient has complained of double vision. ┬áPlease examine their eyes to determine the cause.”

[/ultimate_heading][vc_empty_space image_repeat=”no-repeat”][vc_video link=”https://vimeo.com/149972950″][vc_empty_space image_repeat=”no-repeat”][vc_row_inner row_type=”row” type=”full_width” use_row_as_full_screen_section_slide=”no” text_align=”left” css_animation=””][vc_column_inner width=”1/4″][stat_counter icon_size=”32″ counter_title=”Station Time” counter_value=”20″ counter_suffix=” minutes” speed=”3″][/vc_column_inner][vc_column_inner width=”1/4″][stat_counter icon_size=”32″ counter_title=”Time for this encounter” counter_value=”10″ counter_suffix=” minutes” speed=”3″][/vc_column_inner][vc_column_inner width=”1/4″][stat_counter icon_size=”32″ counter_title=”Maximum time to examine your patient” counter_value=”6″ counter_suffix=” minutes” speed=”3″][/vc_column_inner][vc_column_inner width=”1/4″][stat_counter icon_size=”32″ counter_title=”Minimum time for discussion and questions” counter_value=”4″ counter_suffix=” minutes” speed=”3″][/vc_column_inner][/vc_row_inner][vc_empty_space image_repeat=”no-repeat”][/vc_column][/vc_row][vc_row row_type=”row” use_row_as_full_screen_section=”no” type=”full_width” oblique_section=”no” text_align=”left” css_animation=””][vc_column][vc_accordion style=”accordion”][vc_accordion_tab title=”Common examiner questions”][vc_column_text]Common examiner questions include the following:

  1. What do you think this patient has?
  2. How would you like to investigate this patient next?
  3. What do you think the underlying cause of this patient’s signs is?

[/vc_column_text][/vc_accordion_tab][vc_accordion_tab title=”Diagnosis and clinical signs”][vc_column_text]This patient has a right VIth cranial nerve palsy and is unable to abduct their right eye.[/vc_column_text][/vc_accordion_tab][vc_accordion_tab title=”Discussion”][vc_column_text]

Clinical Features:

A patient with 6th nerve (also called Abducens nerve) palsy will present paralysis of the lateral rectus muscle. Subsequently esotropia may be present, with the eye deviated towards the nose. The patient will complain of horizontal diplopia and may employ head tilting, a manoeuvre that reduces the doubling of images through alignment of binocular vision.

Initial investigation:

Initial investigations include a comprehensive ocular exam to assess the basic functions of the muscles, other ocular nerves and pupillary function. Other nerves should be tested for functionality to see assess the level of lesion. For example, a lesion of the cavernous sinus which will produce altered sensation of the sensory part of the trigeminal nerve.

The 6th cranial nerve starts its course from the pons, where its nucleus is located, traverses through the subarachnoid area and enters the cavernous sinus. From there, it the nerve enters the superior orbital fissure to supply the lateral rectus muscle. An injury at any of these levels can produce a palsy and require different investigations.

Underlying pathology:

It is important to note that the palsy can be either congenital, due to mal-development of the nerves (Duane syndrome), or acquired form that occurs in the setting of a variety of conditions. Stretching or compression of the nerve by a mass lesion such as with tumour and vascular growth or in the setting of raised intracranial pressure. In this case a CT scan or an MRI will be the modality of choice. In case of meningitis, a lumbar puncture should be carried out. Ischemic injuries, those occurring within the setting of diabetes mellitus or hypertension will require monitoring of the blood sugar and pressure levels.

Common treatment:

In children, patches are used to occlude one eye to reduce the chances of development of amblyopia. In adults, patching is employed to reduce the diplopia. Usually, evaluation of esotropia can be done through prismatic measurements. This is important in the assessment of correction and return of functionality or worsening of condition.

[/vc_column_text][/vc_accordion_tab][vc_accordion_tab title=”Specimen case presentation”][vc_column_text]”This patient is unable to abduct their right eye in keeping with a right VIth cranial nerve palsy.”[/vc_column_text][/vc_accordion_tab][/vc_accordion][/vc_column][/vc_row]