What Is Millard Gubler Syndrome?
Millard Gubler syndrome is a disease of the pons, the section of the brainstem that connects the thalamus and medulla oblongata. Millard Gubler syndrome is a condition characterized by a unilateral lesion of the basal region of the caudal pons involving fascicles of the abducens nerve and the facial cranial nerve, along with the fibers of the pyramidal tract. The abducens nerve is the sixth cranial nerve, and the facial nerve is the seventh. Therefore, the diagnosis of Millard Gubler syndrome is confirmed by examination of these nerves and the presence of hemiplegia (paralysis on one side of the body) in the upper or lower extremities. The condition is known as Millard Gubler syndrome after two French doctors, Auguste Louis Jules Millard, who first recognized it in 1855, and Adolphe-Marie Gubler, who wrote about it in a medical journal the following year.
What Are the Other Names of Millard Gubler Syndrome?
Alternate names for Millard Gubler syndrome are:
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Facial abducens hemiplegia syndrome.
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The ventral pontine syndrome.
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MGS (Millard Gubler syndrome).
What Causes Millard Gubler Syndrome?
The cause of Millard Gubler syndrome differs with age. The common causes of Millard Gubler syndrome in the young population include:
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Tumors.
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Infectious diseases like tuberculosis (a serious bacterial infection affecting the lung), neurocysticercosis (an infection caused by the tapeworm, damaging the brain, muscular system, and other body tissues), etc.
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Demyelinating diseases like multiple sclerosis. Demyelinating diseases are diseases that cause damage to the myelin sheath covering the nerve fibers.
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Viral infections like rhombencephalitis (an inflammatory disease that affects the brainstem and the cerebellum).
The common causes of Millard Gubler syndrome in the older population include:
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Hemorrhage (internal bleeding).
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Ischemia (reduced or restricted blood flow to a body part).
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Due to the prepontine subarachnoid hematoma (a condition caused by the bursting of blood vessels in the brain) compressing the arteries.
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Aneurysm (it is an uncommon bulge and a weak part of a blood vessel, artery) of the basilar artery (rare cause).
What Are the Symptoms of Millard Gubler Syndrome?
The common signs and symptoms of Millard-Gubler syndrome include:
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Symptoms primarily occur due to the functional loss of various structures of the pons, including the sixth and seventh cranial nerves and the corticospinal tract fibers.
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Due to the involvement of the pyramidal tract, the extremities became hemiplegic on the opposite side (except the face).
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Lateral rectus paralysis on the same side results in diplopia (double vision). In addition, this diplopia is further increased when the patient sees the lesion side.
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Loss of ability to rotate the afflicted eye outward due to sixth cranial nerve involvement.
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Peripheral facial nerve paresis (muscular weakness due to nerve damage) leads to flaccid paralysis (a syndrome associated with loose and flabby extremities) of the facial expression muscles, and seventh cranial nerve involvement causes loss of corneal reflux.
How Is Millard Gubler Syndrome Diagnosed?
Millard Gubler syndrome can b diagnosed in the following ways:
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Clinical Evaluation: The examination of the sixth and seventh cranial nerves and the presence of hemiplegia (a condition resulting in single-sided muscle weakness) in the upper or lower extremities are major clinical criteria to confirm the diagnosis of Millard-Gubler syndrome. However, a thorough medical history is important to rule out additional reasons like infection or vascular problems because Millard-Gubler syndrome may occur due to various causes.
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Imaging Tests: The lesion can be identified using neurological imaging techniques, including computed tomography (CT) and magnetic resonance imaging (MRI). In addition, a brain MRI is more sensitive and accurate than a CT scan to detect infarcts early, particularly when there are minor pontine lesions. However, there have been rare cases reported where Millard-Gubler syndrome was present, but there were no imaging findings. Imaging tests can also be used to find other related lesions, such as tumors, tuberculomas (a firm, round mass that varies in size from 2 cm to 10 cm), etc.
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Angiography: Vertebral angiography is done in cases where the lesion develops due to basilar artery occlusion.
How Is Millard Gubler Syndrome Treated?
The treatment modalities depend primarily on the cause of the disease. Patients who present with numerous impairments often need early conservative interventions in addition to multidisciplinary rehabilitation.
What Are the Conditions Similar to Millard Gubler Syndrome?
Differential diagnosis of Millard Gubler syndrome includes:
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Ataxic Hemiparesis: It refers to muscle weakness, and ataxia (it is a condition that affects speech, coordination, and balance) occurs on the same side of the body.
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Dysarthria: Dysarthria is the weakness of the speech-related muscles, which frequently results in slurred or slowed speech and other speech difficulties.
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Locked-in Syndrome: Locked-in syndrome occurs due to damage to a specific part of the brainstem. Individuals with this condition have total paralysis but are still conscious and have average cognitive abilities.
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Raymond Syndrome: It refers to a condition occurring due to the blockage of the basilar artery’s circumferential branches.
What Is the Prognosis of Millard Gubler Syndrome?
The severity and cause of the disease have a major impact on the prognosis. Typically, a vertebrobasilar stroke results in serious neurologic disability, which affects the prognosis of the condition. Early intervention and management also play a major role in improving the prognosis of Millard Gubler syndrome. The prognosis of patients with minor lesions is typically better than those with large and complex lesions. Moreover, high fatality rates are reported in patients with acute basilar artery occlusion.
Conclusion:
Millard Gubler syndrome is a rare lesion of the pons. It is a disease that affects the part of the brainstem connecting the thalamus and the medulla oblongata. The disease is known to have variable causes depending on the age. Younger patients have been reported to develop the disease due to tumors, infections, etc. Whereas older individuals usually develop it due to ischemia, aneurysm, hemorrhage, etc. The rate of incidence and the treatment of the condition also depend on the underlying cause.
