Signs and Symptoms of Acoustic Neuroma at Initial Presentation: An Exploratory Analysis

Abstract

Introduction The objective of this study was to describe the most common clinical features associated with an acoustic neuroma diagnosis and to identify those features associated with larger tumour size at initial diagnosis. Methods The clinical information of 945 consecutive patients diagnosed with acoustic neuroma at a single centre between 1992 and 2015 was analysed. Clinical features were examined and the relationship between these features and tumour size (>2.5 cm) was analysed using descriptive statistics and logistic regression analysis. Statistical analysis was performed in R version 3.1.1. Results The most common presenting symptom was a unilateral hearing loss in 752 patients (80%), with a progressive pattern in 90% of these cases. The second most common presenting symptom was unilateral tinnitus, accounting for 6.3%, while ataxia, vertigo and headache accounted for 3.8%, 3.4% and 2%, respectively. The diagnosis of acoustic neuroma was an incidental finding in 20 patients (2.1%). Temporal analysis demonstrated a downward trend in the number of patients presenting with hearing loss and an increased proportion of patients presenting with other symptoms. On multivariate analysis, larger tumour size was associated with abnormal tandem gait (odds ratio 8.9, p=0.02), subjective facial weakness (odds ratio 5.3, p< 0.001), abnormal facial sensation on examination (odds ratio 3.0, p=0.03) and headache (odds ratio 2.6, p< 0.001). Conclusion The majority of patients with acoustic neuroma present with the classic, progressive, unilateral hearing loss. However, the pattern of presentation in acoustic neuroma patients is changing. Features in the history indicative of a larger tumour are headaches and subjective facial weakness, whilst concerning features on examination are abnormal tandem gait and altered facial sensation.

Keywords: acoustic neuroma; diagnosis; epidemiology; signs and symptoms.

Figure 1. Trends in initial presentation with regards to unilateral hearing loss (A) and primary presenting symptom (B)

(A) The proportion of patients presenting with hearing loss as the main presenting symptom is shown on the x-axis (e.g., 0.75 corresponding to 75% of patients). The blue dashed line shows the smoothed pattern over time following a time series analysis. (B) The trend in presenting symptoms other than hearing loss. This demonstrates that in the later years of the study (right side of the graph), there has been an increase in patients presenting with ataxia, vertigo and incidental tumours.

Figure 2. Tumour size in the total cohort (A) and the trend in the proportion of tumours within the larger size categories (B)

The breakdown of larger tumour sizes (i.e., >2.5 cm) is shown in (B), with a decreasing trend in these larger tumours evident over the study period.