Benign Paroxysmal Positional Vertigo (BPPV): This condition is characterized by brief, episodic vertigo triggered by specific head movements, which can occur in both sitting and standing positions. The vertigo episodes are typically short-lived, lasting a few seconds to a minute, which aligns with the patient's report of episodes lasting about 10 seconds. BPPV is a common cause of vertigo and can cause presyncopal symptoms due to the intense, brief vertigo spells.

Vestibular Migraine: This condition can cause episodic vertigo that may last from seconds to days, and it can be accompanied by headache, sensitivity to light and sound, and other migraine symptoms. However, some patients may experience vertigo without headache. The presyncopal feeling could be related to the migraine aura or the vertigo itself.
Labyrinthitis: An inner ear disorder characterized by inflammation of the labyrinth, which can cause sudden onset of vertigo, hearing loss, and sometimes tinnitus. The vertigo can be severe and may lead to presyncopal symptoms.
Meniere's Disease: A disorder of the inner ear that causes episodes of vertigo, tinnitus, hearing loss, and ear fullness. The episodes can be unpredictable and may lead to a feeling of presyncope due to the severity of the vertigo.

Posterior Circulation Stroke or Transient Ischemic Attack (TIA): Although less common, vertigo can be a presenting symptom of a posterior circulation stroke or TIA, especially if accompanied by other neurological symptoms such as dysarthria, diplopia, or ataxia. Missing this diagnosis could be catastrophic.
Multiple Sclerosis: In rare cases, vertigo can be a presenting symptom of multiple sclerosis, particularly if it's associated with other neurological symptoms such as optic neuritis, weakness, or sensory deficits.
Cardiac Arrhythmias: Certain arrhythmias, such as atrial fibrillation, can cause presyncopal symptoms and, less commonly, vertigo due to decreased cardiac output and subsequent cerebral hypoperfusion.

Perilymphatic Fistula: A rare condition where there's an abnormal connection between the inner and middle ear, leading to vertigo, hearing loss, and sometimes tinnitus. The symptoms can be triggered by changes in pressure.
Superior Canal Dehiscence: A rare condition where there's an abnormal opening in the bone overlying the superior canal of the inner ear, leading to vertigo and hearing symptoms that can be triggered by sound or pressure changes.
Chiari Malformation: A structural defect in the cerebellum that can cause vertigo among other neurological symptoms, due to the compression of the cerebellum and brainstem.