Application of bedside HINTS, ABCD2 score and truncal ataxia to differentiate cerebellar-brainstem stroke from vestibular neuritis in the emergency room

BACKGROUND AND PURPOSE

Acute vestibular syndrome (AVS) typically manifests as isolated dizziness or vertigo with no apparent neurological impairments. However, distinguishing life-threatening stroke from innocuous peripheral vestibular lesions in the emergency room (ER) remains challenging. This study aimed to explore the ability of the head impulse-nystagmus-test of skew (HINTS) combined with truncal ataxia or ABCD2 score to differentiate stroke from peripheral vestibular disease in patients with AVS in the ER.

METHODS

We prospectively recruited 121 patients with AVS from December 2022 to June 2023, 69 of whom presented with vestibular neuritis (VN) and the remaining with posterior circulation stroke (PCS). We analysed the HINTS results, truncal ataxia and ABCD2 score and compared the sensitivity and specificity among HINTS, truncal ataxia, ABCD2 score and their combinations using the McNemar test for paired samples.

RESULTS

HINTS combined with grade 2-3 truncal ataxia achieved significantly higher sensitivity than that of isolated HINTS in differentiating PCS from VN (100% vs 88.5%, p=0.031). The specificity of HINTS plus grade 2-3 truncal ataxia did not significantly differ from that of isolated HINTS (p=0.125); however, the combination of ABCD2 score and HINTS did not improve the diagnostic accuracy. The sensitivity of ABCD2 score ≥4 plus grade 2-3 truncal ataxia was significantly higher than those of isolated ABCD2 score ≥4 or isolated grade 2-3 truncal ataxia (p=0.016 and p<0.001, respectively) and not significantly lower than that of isolated HINTS (p=0.508).

CONCLUSION

Compared with the ABCD2 score, the truncal ataxia is of more valuable assistance to HINTS in differentiating PCS. Although the combination of ABCD2 score and truncal ataxia has a significant implication, it is not a replacement for HINTS.

Bedside Testing in Acute Vestibular Syndrome-Evaluating HINTS Plus and Beyond-A Critical Review

Acute vertigo and dizziness are frequent presenting symptoms in patients in the emergency department. These symptoms, which can be subtle and transient, present diagnostic challenges because they can be caused by a broad range of conditions that cut across many specialties and organ systems. Previous work has emphasized the value of combining structured history taking and a targeted examination focusing on subtle oculomotor signs. In this review, we discuss various diagnostic bedside algorithms proposed for the acutely dizzy patient. We analyzed these different approaches by calculating their area-under-the-curve (ROC) characteristics and sensitivity/specificity. We found that the algorithms that incorporated structured history taking and the use of subtle oculomotor signs had the highest diagnostic accuracy. In fact, both the HINTS+ bedside exam and the STANDING algorithm can more accurately diagnose acute strokes than early (<24 to 48 h after symptom onset) MRI with diffusion-weighted imaging (DWI). An important caveat is that HINTS and STANDING require moderate training to achieve this accuracy. Therefore, for physicians who have not undergone adequate training, other approaches are needed. These other approaches (e.g., ABCD2 score, PCI score, and TriAGe+ score) rely on vascular risk factors, clinical symptoms, and focal neurologic findings. While these other scores are easier for frontline providers to use, their diagnostic accuracy is far lower than HINTS+ or STANDING. Therefore, a focus on providing dedicated training in HINTS+ or STANDING techniques to frontline clinicians will be key to improving diagnostic accuracy and avoiding unnecessary brain imaging.

A Unique Case with Oral Dyskinesia, Chorea, Ataxia, and Mild Cognitive Impairment with Caudate Atrophy and Characteristic Brain Calcifications

The authors report a man who developed oral dyskinesia at 46 years of age, followed by slowly progressive choreic movement and mild cognitive impairment over 20 years. He showed caudate atrophy and four types of intracranial calcification in the hippocampus (dot-like), cerebellar white matter (vague-mass), occipital cortices (laminar), and cerebral white matter (linear). Linear-calcification in the corona radiata seems to be deposition along small veins, which may be related to the white matter changes and to the decreased regional cerebral blood flow in the frontal and parietal lobes. The present case shows a slowly progressive disease with caudate atrophy and characteristic brain calcifications.

Clinical Study of Seven Patients with Infarction in Territories of the Anterior Inferior Cerebellar Artery

BACKGROUND

The prominent features of anterior inferior cerebellar artery (AICA) infarction are vertigo, cerebellar ataxia, and impaired hearing. The present study investigated neurological characteristics associated with AICA infarction.

MATERIALS AND METHODS

The locations of infarcts in 7 patients (age, 32-72 years) with AICA infarction were divided into the lower lateral pons, the middle cerebellar peduncle (MCP), and the cerebellum.

RESULTS

Ischemic lesions were located in the MCP in 6 patients, spread to the lower lateral pons in 3, and involved the cerebellum in 4 patients. Standing posture and gait were impaired in all patients. Five and 4 patients had impaired hearing and vertigo, respectively. Two patients had only symptoms of labyrinthine disease, and 1 had these symptoms accompanied by impaired hearing. The symptoms in 2 patients with the lesion in the lateral pons were consistent with those in Gasperini syndrome. Two of 3 patients without vertigo had ataxia of the extremities. Stenosis of the vertebral artery or basilar artery in 5 patients indicated that the etiology was branch atheromatous disease.

CONCLUSIONS

The most prominent symptom of truncal and gait ataxia and the frequent association between vertigo and impaired hearing were consistent with the characteristics of AICA infarction. Two patients without vertigo had ataxia of the trunk and extremities that might have been due to involvement of the dorsal spinocerebellar tract in the inferior cerebellar peduncle.

The Diagnostic Accuracy of Truncal Ataxia and HINTS as Cardinal Signs for Acute Vestibular Syndrome

The head impulse, nystagmus type, test of skew (HINTS) protocol set a new paradigm to differentiate peripheral vestibular disease from stroke in patients with acute vestibular syndrome (AVS). The relationship between degree of truncal ataxia and stroke has not been systematically studied in patients with AVS. We studied a group of 114 patients who were admitted to a General Hospital due to AVS, 72 of them with vestibular neuritis (based on positive head impulse, abnormal caloric tests, and negative MRI) and the rest with stroke: 32 in the posterior inferior cerebellar artery (PICA) territory (positive HINTS findings, positive MRI) and 10 in the anterior inferior cerebellar artery (AICA) territory (variable findings and grade 3 ataxia, positive MRI). Truncal ataxia was measured by independent observers as grade 1, mild to moderate imbalance with walking independently; grade 2, severe imbalance with standing, but cannot walk without support; and grade 3, falling at upright posture. When we applied the HINTS protocol to our sample, we obtained 100% sensitivity and 94.4% specificity, similar to previously published findings. Only those patients with stroke presented with grade 3 ataxia. Of those with grade 2 ataxia (n = 38), 11 had cerebellar stroke and 28 had vestibular neuritis, not related to the patient’s age. Grade 2–3 ataxia was 92.9% sensitive and 61.1% specific to detect AICA/PICA stroke in patients with AVS, with 100% sensitivity to detect AICA stroke. In turn, two signs (nystagmus of central origin and grade 2–3 Ataxia) had 100% sensitivity and 61.1% specificity. Ataxia is less sensitive than HINTS but much easier to evaluate.