To determine if two-dimensional and volumetric imaging parameters in vestibular schwannomas (VS) correlate with hearing loss at presentation.
Forty-one cases of pathologically confirmed sporadic VS were analyzed. Maximal tumor dimensions in anteroposterior (AP), coronal (ML), and craniocaudal (CC) dimensions were obtained along with tumor-fundus distance and internal auditory canal (IAC) porus diameters. Volumetric analysis was done on 37 cases. Tumors volumes were calculated through both 3-D volumetric and ABC/2 [AP × ML × CC/2] methodology. With the 3-D method, total tumor volume (TTV), and cerebellopontine angle (CPA) tumor volume were separately calculated and IAC volumes obtained by subtracting CPA tumor volumes from TTV. Pure tone average (PTA) and speech discrimination scores (SDS) were correlated with tumor dimensions.
Non-volumetric analysis was performed on 41 tumors. The AP and ML dimensions correlated with both PTA and SDS (p < 0.05). No significant correlations were seen between hearing loss and tumor-fundus distance or porus diameters. The tumor volume calculated through ABC/2 methodology correlated with PTA and SDS (p < 0.05). The 3-D TTV and CPA volumes only correlated with PTA. IAC tumor volumes did not correlate with hearing loss.
Maximal AP and ML dimensions are the only non-volumetric variables, which significantly correlate with hearing loss. Tumor volume calculated through ABC/2 method significantly correlates with hearing impairment while the 3-D TTV and CPA tumor volumes only correlated significantly with PTA scores but not SDS scores.
*Department of Radiology, University of Iowa Hospitals and Clinics, Iowa City
†Iowa Methodist Medical Center, Des Moines
‡Department of Otolaryngology–Head and Neck Surgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa
Address correspondence and reprint requests to Girish Bathla, FRCR, Department of Radiology, University of Iowa Hospitals and Clinics, 200 Hawkins Drive, Iowa City, IA 52242; E-mail: Girishemail@example.com
Source of funding: None.
Author contributions: Guarantor of integrity of the entire study—GB, BP, KB; Study concepts and design—GB, BP; Study design—GB, BP; Definition of intellectual content—BP, MRH; Literature research—GB, MRH, BP; Clinical studies—N/A; Experimental studies—N/A; Data acquisition—BC, GB, MRH; Data analysis—GB, BC, KB; Statistical analysis—KB; 11 Manuscript preparation—GB, BC, KB, BP; Manuscript editing—KB, BP, MRH, GB; Manuscript review—KB, BP, MRH, GB
The authors disclose no conflicts of interest.