Patients with basilar migraine make up only a small fraction of all migraine sufferers and there are formal International Headache Society (IHS) criteria for diagnosis [15]. Patients are typically younger women who have an occipital headache that is preceded by less than 1 h of aura. The aura can include typical visual auras, visual field defects, vertigo, dysarthria, diplopia, tinnitus, hearing loss, ataxia, bilateral paresthesias, mental status changes, or bilateral limb weakness. The reason basilar migraine can occasionally be confused with MDVM is that MDVM can include symptoms of migraine headache, vertigo, tinnitus, and, rarely, a transient low-frequency sensorineural hearing loss (SNHL) [16, 17].

Idiopathic intracranial hypertension has gone by many previous names such as benign intracranial hypertension and pseudotumor cerebri. It typically presents in women aged 20–40 years with an elevated body mass index (BMI) ≥25 kg/m². Holocephalic headache without migrainous features and low-tone SNHL and vertigo have been reported, explaining why idiopathic intracranial hypertension is included in the differential for MDVM. Up to 25 % of untreated patients can develop vision loss or blindness. Other symptoms include pulsatile tinnitus, nausea, vomiting, nonspecific dizziness, imbalance, and visual flashes of light (scotomas). Patients do not have focal neurologic deficits or mental status changes. An MRI with a partial or completely empty sella turcica is suggestive of elevated intracranial pressure, but the diagnosis requires that the modified Dandy criteria be met, including: symptoms of increased intracranial pressure, non-focal neurologic exam with the exception of abducens palsy, normal mental status, normal imaging studies (not including empty sella on MRI), lumbar puncture opening pressures of greater than 250 mm H₂O without cytological or chemical abnormality, and no other explanation for raised intracranial pressure [18]. Although many physicians rely heavily on the presence or absence of ocular papilledema as a diagnostic screening, it is absent in 5–10 % of confirmed cases [19].

Vertebrobasilar insufficiency (VBI) is an intracranial posterior circulation transient ischemic attack (TIA), which, if left untreated, can lead to posterior cerebral infarction (anterior inferior cerebellar artery (AICA) or posterior inferior cerebellar artery (PICA) infarct). Most patients are over the age of 60 years and also have atherosclerotic risk factors such as smoking, high cholesterol, and hypertension. Multiple spontaneous bouts of vertigo can occur that usually last less than 20 min but can be longer. Clusters of attacks have been reported. Many times vertigo is brought on by neck extension; however, this is not always necessary. Around 19 % of patients present with vertigo without associated symptoms such as diplopia, visual loss, visual field deficit, dysarthria, dysphagia, mental status changes, or extremity weakness or clumsiness. Finally, headaches occur in 14 % of patients, explaining its inclusion in the differential diagnosis of MDVM. If isolated and repetitive vertigo has occurred for over 6 months without additional symptoms appearing, then VBI is unlikely to be the diagnosis [17, 20]. VBI diagnosis is usually confirmed with MRI/MRA or CT angiogram.

Benign recurrent vertigo (BRV) is a diagnosis given to patients with recurrent spontaneous vertigo that demonstrates overlapping features with vestibular migraine, Ménière’s disease, or MDVM; however BRV patients do not meet formal diagnostic criteria for any of these conditions. This is usually due to a lack of documented audiometric hearing loss or consistent timing between vertigo spells and migrainous symptoms. BRV has suffered from a lack of consistent nomenclature (chronic vestibulopathy, recurrent vestibulopathy, vestibular Ménière’s disease) and diagnostic validity. However, the stricter the vestibular migraine and Ménière’s disease criteria get, the more patients will default into this category. A few studies have shown that most of these patient’s symptoms will spontaneously resolve and do not evolve into Ménière’s disease [21, 22]. Similarly, most of these patients have migraine symptoms, such as photophobia, or strong family histories of migraine and, thus, from a practical clinical standpoint should be treated similar to vestibular migraine [14].

A primary difficulty in diagnosing and categorizing Ménière’s disease and vestibular migraine is that some physicians have not adopted the Bárány classification of vestibular symptoms that are at the core of Ménière’s disease and vestibular migraine definition [32]. Furthermore, there is yet no universal agreement as to which vertigo descriptions should be included in “typical” Ménière’s disease and vestibular migraine dizziness attacks. An example of such, Sargent used the Bárány definition of internal vertigo which is described as a “sense of self-motion when no motion is occurring, or the sensation of distorted self-motion during an otherwise normal head movement” when describing Ménière’s disease vertigo [8]. This definition did not include external vertigo, which is “a false sensation that the visual surround is spinning or flowing” which most physicians would also include [32]. Another problem with the definitions when applied to Ménière’s disease and vestibular migraine is that certain descriptions of internal or external vertigo do not likely belong in Ménière’s disease or vestibular migraine disease classification. An example of such includes this description of internal vertigo: “there is a spinning inside of my head; or it feels as if my brain is turning within my skull.” This sensation of internal vertigo is more likely described with conversion disorder and does not fall into most clinician’s definition of Ménière’s disease or vestibular migraine-like vertigo. Lastly, physicians have the problem that the patient may not be able to reliably discriminate these subtleties and relay them accurately. It is the author’s experience that many cannot.

Increasing recognition of vestibular migraine criteria such as the Neuhauser criteria or the most recent Bárány and IHS society definition can only help to better categorize these patients for prognosis and treatment trials [33, 34]. However, there are some issues with these criteria when it comes to treating everyday Ménière’s disease, vestibular migraine, and MDVM patients. The regular temporal pattern of migraine headache and vestibular symptoms is absent in 30–50 % of reported vestibular migraine patients, and up to 30 % of patients eventually diagnosed with vestibular migraine will initially present without headache [12, 35]. Alternatively, vestibular migraine criteria have increasingly demanded this temporal relationship with the exclusion of greater numbers of patients. As mentioned, this will likely be helpful in studying the natural course of vestibular migraine and treatment effects by ensuring a greater purity in vestibular migraine patient inclusion. However, in the clinical arena, this has left an increasing number of patients without a diagnosis or at least an attempt at empirical treatment for vestibular migraine. Hopefully, the increasing exclusion of these patients will lead to the discovery of a new diagnostic phenotype rather than including them in “waste basket” diagnoses such as BRV or shifting them to other vertigo diagnoses that equally do not fit such as Ménière’s disease or BPPV.

Another major clinical challenge is that there is currently no history, physical exam, vestibular test, or imaging finding that is pathognomonic for Ménière’s disease alone, vestibular migraine alone, or MDVM [12]. This may be from a limitation in the current classification systems and limitations in current testing capabilities and technology, or it may be that these two entities are not distinguishable and are slightly different phenotypic presentations of an underlying unifying pathophysiology. More research is necessary to clarify the definitions in the future. Clearly certain historical points build evidentiary support for vestibular migraine, Ménière’s disease, or MDVM, but significant exceptions always exist for the clinician. For example, classic Ménière’s disease symptoms of subjective fluctuating or progressive hearing loss, tinnitus, and aural fullness occur in vestibular migraine patients 36, 55, and 51 % of the time, respectively. Conversely, vestibular migraine symptoms of headache, photophobia episodes, and aura occur in 81, 40, and 22 % of Ménière’s disease sufferers who do not meet formal vestibular migraine criteria [3]. As a common practice, vestibular testing is frequently used to rule Ménière’s disease “in or out,” but this is not really possible since many Ménière’s disease patients have normal vestibular testing results, especially early in the disease process. Additionally, vestibular migraine patients have abnormalities in VNG, rotary chair, VEMP, and ECoG in up to 15–35 % of patients [3, 12, 14, 36, 37]. Newer tests such as ocular VEMP (oVEMP) and intratympanic gadolinium-enhanced MRI scans hold some promise for help in distinguishing vestibular migraine and Ménière’s disease. However, early reports are also showing overlaps in abnormalities in Ménière’s disease and vestibular migraine patients. Zuniga et al. were unable to find any cVEMP or oVEMP test that could distinguish between Ménière’s disease and vestibular migraine [38]. Additionally, 19 consecutive definite and probable vestibular migraine patients without Ménière’s disease or hearing loss were scanned with intratympanic gadolinium-enhanced MRI technique, and 4 (19 %) were found to have endolymphatic hydrops [39]. Currently, the 1995 AAO Ménière’s disease guidelines should be used to diagnose Ménière’s disease, and the Bárány society criteria should be used for vestibular migraine [4, 32]. If the patient meets the criteria for both, then the diagnosis of MDVM should be made. Objective SNHL criteria for low-tone PTA per the 1995 AAO Ménière’s disease guidelines are the most specific criteria for Ménière’s disease diagnosis. Future Ménière’s disease criterion revisions might consider adding speech discrimination score requirements to the audiologic requirements. Finally, a history of moderate or severe headache and photophobia during vertigo spells was the most specific diagnostic history point for vestibular migraine diagnosis [3].