Facial Colliculus Syndrome

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1- Introduction

2- Anatomical Overview

3- Causes

4- Treatment 


Facial colliculus syndrome, also known as facial colliculus syndrome (FCS), is a rare neurological condition that arises from a lesion in the dorsal pons, a part of the brainstem. The facial colliculus is an anatomical landmark in the pons, formed by the internal genu of the facial nerve as it loops around the abducens nucleus. This syndrome affects both the facial nerve (cranial nerve VII) and the abducens nerve (cranial nerve VI), leading to specific clinical manifestations.
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Anatomical Overview

The facial colliculus is a significant anatomical structure located on the dorsal aspect of the lower pons, in the brainstem. It is formed by the internal genu of the facial nerve (cranial nerve VII) looping around the abducens nucleus (cranial nerve VI). Here is a detailed anatomical overview of the facial colliculus:

Location and Structure

  • Dorsal Pons: The facial colliculus is situated on the floor of the fourth ventricle, within the tegmentum of the lower pons. It is visible as a slight elevation in this region.
  • Internal Genu of the Facial Nerve: The fibers of the facial nerve form an internal loop around the abducens nucleus. This looping creates the prominence known as the facial colliculus.
  • Abducens Nucleus: This nucleus lies beneath the facial colliculus and is responsible for innervating the lateral rectus muscle of the eye, which controls its outward movement.


  • Vascular Causes

    1. Stroke:

      • Ischemic Stroke: Caused by a blockage of blood flow to the brainstem, leading to localized damage in the area of the facial colliculus.
      • Hemorrhagic Stroke: Resulting from bleeding into the brainstem tissue, which can directly damage the facial colliculus.
    2. Cavernous Malformations:

      • Abnormal clusters of blood vessels in the brainstem that can bleed or compress adjacent neural structures, including the facial colliculus.


    1. Brainstem Gliomas:

      • Tumors originating from glial cells within the brainstem that can affect the pons and the facial colliculus.
    2. Metastatic Tumors:

      • Secondary tumors that have spread to the brainstem from other parts of the body, potentially impacting the facial colliculus.

    Inflammatory and Demyelinating Conditions

    1. Multiple Sclerosis (MS):

      • An autoimmune disorder causing demyelination in the central nervous system, including the brainstem. Lesions in the pons can affect the facial colliculus.
    2. Neurosarcoidosis:

      • A chronic inflammatory disease that can involve the central nervous system, including the brainstem, leading to granuloma formation and affecting the facial colliculus.


    1. Bacterial Infections:

      • Conditions such as bacterial meningitis can cause inflammation and abscess formation in the brainstem, potentially impacting the facial colliculus.
    2. Viral Infections:

      • Viral encephalitis or other viral infections that cause inflammation of the brainstem can lead to damage in the area of the facial colliculus.


    1. Brainstem Injury:
      • Traumatic injury to the brainstem from head trauma, such as in accidents, can damage the facial colliculus.

    Degenerative and Metabolic Disorders

    1. Multiple System Atrophy (MSA):

      • A neurodegenerative disorder that affects multiple systems, including the autonomic nervous system and motor control, potentially involving the brainstem.
    2. Mitochondrial Diseases:

      • Disorders affecting cellular energy production that can cause widespread neurological symptoms, including damage to the brainstem.


  • Treatment of facial colliculus syndrome depends on the underlying cause:

    1. Medical Management:

      • Steroids: For inflammatory conditions such as multiple sclerosis or neurosarcoidosis.
      • Antibiotics or Antivirals: For infectious causes.
      • Anticoagulants or Thrombolytics: For stroke management.
    2. Surgical Intervention:

      • Tumor Resection: Surgical removal of brainstem tumors if feasible.
      • Vascular Surgery: For cavernous malformations or aneurysms.
    3. Supportive Care:

      • Physical Therapy: To help with facial muscle exercises.
      • Eye Care: Use of eye patches or lubricating drops to manage symptoms of diplopia and protect the eye.
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