Evaluation of patients with vertigo of vertebrobasilar insufficiency origin using auditory brainstem response, electronystagmography, and transcranial Doppler

ACR Appropriateness Criteria® Dizziness and Ataxia: 2023 Update

Diagnostic evaluation of a patient with dizziness or vertigo is complicated by a lack of standardized nomenclature, significant overlap in symptom descriptions, and the subjective nature of the patient's symptoms. Although dizziness is an imprecise term often used by patients to describe a feeling of being off-balance, in many cases dizziness can be subcategorized based on symptomatology as vertigo (false sense of motion or spinning), disequilibrium (imbalance with gait instability), presyncope (nearly fainting or blacking out), or lightheadedness (nonspecific). As such, current diagnostic paradigms focus on timing, triggers, and associated symptoms rather than subjective descriptions of dizziness type. Regardless, these factors complicate the selection of appropriate diagnostic imaging in patients presenting with dizziness or vertigo. This document serves to aid providers in this selection by using a framework of definable clinical variants. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Intraoperative Brainstem Auditory Evoked Potentials and Postoperative Nausea and Vomiting After Microvascular Decompression

BACKGROUND

We performed this study to investigate the effect of intraoperative brainstem auditory evoked potential (IBAEP) changes on the development of postoperative nausea and vomiting (PONV) after microvascular decompression (MVD) for neurovascular cross compression.

METHODS

A total of 373 consecutive cases were treated with MVD. The use of rescue antiemetics after surgery was used as an objective indicator of PONV. IBAEP monitoring was routinely performed in all.

RESULTS

The use of rescue antiemetics was significantly associated with female sex (OR = 3.427; 95% CI, 2.077-5.654; P < 0.001), PCA use (OR = 3.333; 95% CI, 1.861-5.104; P < 0.001), and operation time (OR = 1.017; 95% CI, 1.008-1.026; P < 0.001). A Wave V peak delay of more than 1.0 milliseconds showed a significant relation with the use of rescue antiemetics (OR = 1.787; 95% CI, 1.114-2.867; P = 0.016) and a strong significant relation with the use of rescue antiemetics more than 5 times (OR = 2.426; 95% CI, 1.372-4.290; P = 0.002).

CONCLUSIONS

A wave V peak delay of more than 1.0 milliseconds might have value as a predictor of PONV after MVD. More detailed neurophysiological studies will identify the exact pathophysiology underlying PONV after MVD.

Benign Paroxysmal Positional Vertigo and the Increased Risk of Ischemic Stroke: A Nested Case-Control Study Using a National Cohort Sample

A recent population cohort study reported that benign paroxysmal positional vertigo (BPPV) was a risk factor for ischemic stroke. This study investigated the risk of ischemic and hemorrhagic strokes in patients with BPPV. A nested case-control study used the data from the Korean National Health Insurance Service-National Sample Cohort between 2002 and 2013. We used data of patients aged ≥50 years obtained from the Korean National Health Insurance Service-National Sample Cohort between 2002 and 2013. A total of 15,610 patients with ischemic stroke and 4,923 patients with hemorrhagic stroke were matched for age, sex, income, residential location, hypertension, diabetes, and dyslipidemia with 62,440 and 19,692 controls, respectively. History of BPPV was evaluated in the stroke and control groups. Crude and adjusted odds ratios (ORs) for stroke in patients with BPPV were analyzed using stratified logistic regression analysis. Subgroup analyses were performed for age and sex. Notably, 3.7% (572/15,610) of patients with ischemic stroke and 2.7% (1,702/62,440) of the control subjects reported a history of BPPV (P < 0.001). The adjusted OR for BPPV in patients with ischemic stroke was 1.35 (95% confidence interval (CI) 1.22-1.49, P < 0.001). Patients with ischemic stroke showed higher ORs for BPPV in the subgroup of women. Patients with hemorrhagic stroke did not show a high OR for BPPV. Ischemic stroke patients demonstrated the increased OR for BPPV in subjects aged ≥50 years old.

Neurosonology Accuracy for Isolated Acute Vestibular Syndromes

OBJECTIVES

The clinical approach to acute vestibular syndromes is often complex for the physician. Neurosonology offers a noninvasive method to study the cervicocephalic circulation when a vascular etiology is suspected. We aim to evaluate the diagnostic accuracy of a vascular neurosonological exam in isolated acute vestibular syndrome.

METHODS

All patients submitted to cerebrovascular ultrasound and magnetic resonance imaging during the period between 2011 and 2015 with acute isolated vestibular syndrome. Those with any clinical sign of brainstem lesion on presentation were excluded. All patients performed the neuroimaging study (brain computed tomography and magnetic resonance imaging) and neurologic surveillance. Neurosonological exam included all intra- and extracranial segments of the vertebrobasilar circulation. Positive ultrasound exam was defined as the presence of stenotic or occlusive disease in any of these segments related to the infarcted area.

RESULTS

A total of 108 patients were included: 60 (53.6%) were males (mean age: 60.75 years (standard deviation, 14.17)). In 27 patients (25.0%) a cerebral ischemic lesion was found to be the cause of the vertigo. Neurosonological assessment showed a sensitivity of 40.7% (95% confidence interval (CI): 22.4; 61.2), specificity of 100% (95% CI: 95.5; 100.0), positive predictive value (PPV) of 100% (95% CI: 71.5; 100.0), and negative predictive value (NPV) of 83.5% (95% CI: 74.6; 90.3).

CONCLUSIONS

Our study suggests that cerebrovascular ultrasound is a highly specific method for the diagnosis of cerebrovascular vertigo. However, its low sensitivity makes it a poor candidate for screening.

The comparative analyses of the auditory evoked potentials and color Doppler sonography findings in patients diagnosed with vertebrobasilar insufficiency

Auditory evoked potentials (AEP) represent an electrophysiological method used in the diagnostics of pathological changes of the brainstem. Patients with vertebrobasilar insufficiency (VBI) show changes in the AEP-caused ischemia of the brain structures that generate their responses. The aim of the study was to determine the diagnostic significance and correlation among the findings of AEP in patients with VBI established by color Doppler sonography. The cross-sectional and prospective research included 48 inpatients and outpatients treated at the Clinic of Neurology, Clinical Center Nis. Ultrasound Doppler of blood vessels in the neck included an examination of the carotid blood vessels, the outcome and all sonographically available parts of the vertebral artery (VA) with particular emphasis on the intravertebral segment (V2). The morphological and hemodynamic characteristics of VA in this segment were monitored, and it was important to test the systolic velocity in two adjacent intervertebral spaces. Auditory evoked potentials were used to monitor the amplitudes, absolute latencies of waves I, II, III, IV, and V, as well as interwave latencies (IWLs) I-III, III-V, and I-V. There is statistically significant difference in the more frequent pathological finding of AEP in patients with higher degree of the reduced flow of VA established by color Doppler (P < 0.05) compared to patients with less reduction in the flow. Pathological findings of AEP are well correlated with pathological findings of VBI in color Doppler, and it may be applied as an additional and useful marker in diagnosis of VBI.

Isolated rotational vertigo due to internal capsular infarction

Isolated rotational vertigo is most often associated with disorders of the semicircular canals, vestibular nerve, brainstem, or cerebellum but rarely observed following a supratentorial stroke. A 64-year-old man developed sudden onset of vertigo and horizontal right-beating nystagmus with a torsional component in primary and eccentric gazes, unsteady gait, and axial lateropulsion to the right side. Magnetic resonance imaging demonstrated an infarction in the posterior limb of left internal capsule, an unusual cause of the patient's signs and symptoms.