[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) › Vermis [Nervous system](https://durgical.com/en/anatomy/system/nervous-system/) · [Head and neck](https://durgical.com/en/anatomy/region/head-and-neck/) # Vermis The vermis is the narrow middle strip of the [cerebellum](https://durgical.com/en/anatomy/anterior-quadrangular-lobule/); it controls trunk balance and walking and is the first part damaged by alcohol. Official name: Central lobule [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=head_neck&select=cerebellar_vermis&side=r) Opens in the Durgical app, no sign-up needed. ## What it is The narrow middle strip of the cerebellum. ## What it does Controls trunk balance and walking; alcohol damages it first. ## Key points - Midline lesions cause truncal ataxia: a broad-based, staggering gait and swaying when sitting or standing, while finger-to-nose may be normal - Chronic alcohol use degenerates the upper front vermis first, so walking and heel-to-shin fail while the arms are spared - In children, medulloblastoma usually arises in the vermis, fills the fourth ventricle and causes obstructive hydrocephalus with morning vomiting and unsteadiness - The fastigial nucleus lies under it; with the nodulus (flocculonodular lobe) it controls balance and eye movements through the vestibular nuclei ## Key facts **Where** Midline of the cerebellum **Blood supply** SCA, PICA **Function** Trunk balance and gait (damaged first by alcohol) ## Relations **Lateral** Cerebellar hemispheres, through the paravermal zone **In front** Roof of the [fourth ventricle](https://durgical.com/en/anatomy/fourth-ventricle/): superior medullary velum above; nodulus and inferior medullary velum below **Above** [Tentorium cerebelli](https://durgical.com/en/anatomy/tentorium-cerebelli/) at its junction with the [falx cerebri](https://durgical.com/en/anatomy/falx-cerebri/), which holds the [straight sinus](https://durgical.com/en/anatomy/straight-sinus/); the great cerebral vein in front **Below** Vallecula between the [cerebellar tonsils](https://durgical.com/en/anatomy/tonsil-of-cerebellum/), opening onto the cisterna magna **Behind** Posterior cerebellar notch with the falx cerebelli and the internal occipital crest ## How to find it It cannot be felt. On midline sagittal MRI it is the branching central strip of the cerebellum behind the fourth ventricle; front to back its lobules are lingula, central lobule, culmen, declive, folium, tuber, pyramid, uvula and nodulus, the primary fissure lying between culmen and declive. Surgeons reach it through a midline suboccipital opening, between the hemispheres. ## Examination - Tandem gait (heel to toe along a straight line): a vermis lesion makes it fail early, with a wide-based, lurching walk, even when finger-to-nose and heel-to-shin are nearly normal - Balance sitting and standing with the eyes open: swaying of the trunk or the need to stand with the feet far apart points to a midline cerebellar problem - Romberg test: with a vermis lesion the person is already unsteady with the eyes open and closing them adds little; clear worsening only when the eyes close points instead to loss of position sense ## On imaging Sagittal MRI shows its full outline. Dandy–Walker malformation: a small or absent vermis with a cystic fourth ventricle in an enlarged posterior fossa. Joubert syndrome: vermis hypoplasia with a 'molar tooth' [midbrain](https://durgical.com/en/anatomy/midbrain/) on axial images. ## Clinical notes - Splitting the vermis to reach the fourth ventricle in children can be followed, a day or more later, by cerebellar mutism (posterior fossa syndrome): loss of speech with irritability that usually improves over weeks to months - Dandy–Walker malformation: a small, upwardly rotated vermis with a cystic, enlarged fourth ventricle and a large posterior fossa; often seen on prenatal ultrasound, and many children develop hydrocephalus - A stroke or bleed in the vermis can present as sudden vertigo with inability to stand or walk while the limbs move well; it mimics an inner ear disorder and is easily missed ## Development The two cerebellar plates, from the rhombic lips of the hindbrain, fuse in the midline to form the vermis; failure of this growth underlies vermian hypoplasia. ## Memory aid Vermis = midline = trunk; hemispheres = limbs on the same side. ## Related conditions - [Wernicke encephalopathy (thiamine deficiency)](https://durgical.com/en/conditions/wernicke-encephalopathy/) - [Ataxia-telangiectasia](https://durgical.com/en/conditions/ataxia-telangiectasia/) - [Childhood brain tumours (medulloblastoma, pilocytic astrocytoma, craniopharyngioma)](https://durgical.com/en/conditions/childhood-brain-tumours/) - [Spinocerebellar ataxias (autosomal dominant ataxias)](https://durgical.com/en/conditions/spinocerebellar-ataxias/) ## Test yourself Think of the answer, then tap the question to see it. ## What does a lesion of the cerebellar vermis cause? Truncal ataxia: a broad-based, staggering gait and swaying when sitting or standing, while finger-to-nose may be normal. ## Which part of the vermis does chronic alcohol use damage first, and what fails? The upper front vermis: walking and heel-to-shin fail while the arms are spared. ## How does a medulloblastoma of the vermis present in a child? It fills the fourth ventricle and causes obstructive hydrocephalus, with morning vomiting and unsteadiness. [Add to my cards (3)](https://durgical.app/estudiar/?add=/en/anatomy/central-lobule/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** lobulus centralis vermis TA2 5821 **Official Spanish (DeCS)** Vermis Cerebeloso DeCS D065814 **English (TA2)** Central lobule **Also called** lobus centralis vermis ## Related - [Cerebellar arteries](https://durgical.com/en/anatomy/superior-cerebellar-artery/) Sources: Terminologia Anatomica (TA2); [DeCS](https://decs.bvsalud.org/es/ths/resource/?id=55496); [Neuroanatomy, Cerebellum](https://www.ncbi.nlm.nih.gov/books/NBK538167/); [Neuroanatomy, Nucleus Fastigial](https://www.ncbi.nlm.nih.gov/books/NBK547738/); [16.5 The Coordination and Gait Exams](https://openstax.org/books/anatomy-and-physiology-2e/pages/16-5-the-coordination-and-gait-exams) (OpenStax (Rice University), 2022) · adapted, [CC BY 4.0](https://creativecommons.org/licenses/by/4.0/); Tratado de anatomía humana (9.ª ed.), tomo II, Libro V, sección 2 (Encéfalo), capítulos I-V: bulbo, protuberancia, cerebelo, cuarto ventrículo, mesencéfalo. ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/central-lobule/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/central-lobule/