Overview

The trigeminal nerve is a mixed cranial nerve, and the afferent and efferent projections of cranial nerve V (CN V) provide sensorimotor inputs and outputs to the face ( Ia.bleJ.0-1 ).[1] The multimodal sensory components (pain, temperature, position, and light touch) of the trigeminal system send projections via the thalamus to primary sensory cortices (Brodmann areas 3, 1, 2). The three primary sensory nerves of the trigeminal system are named for the facial regions they innervate (e.g., ophthalmic

[V1], maxillary [V2], and mandibular [V3]) ( Fig 10-1 A). The unilateral cutaneous sensory distributions of these nerves overlap slightly in the facial midline, which has clinical relevance especially in assessing patients with nonorganic sensory loss (see later). In contrast, first order motor efferents originate in primary motor cortex (area 4) and project bilaterally to the pontine trigeminal motor nucleus. Axon collaterals extend to the thalamus and cerebellum. The motor projections innervate the muscles of mastication including the masseter, medial and lateral pterygoid, temporalis, mylohyoid, and anterior belly of the digastric muscles, as well as the tensors tympani and vela palatini. The motor portion of the trigeminal nerve runs with the mandibular (V3) sensory branch in the face.

Alcohol No More

Alcohol No More

Do you love a drink from time to time? A lot of us do, often when socializing with acquaintances and loved ones. Drinking may be beneficial or harmful, depending upon your age and health status, and, naturally, how much you drink.

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