OBJECTIVE: To compare the results between auditory steady-state response (ASSR) and 40 Hz auditory event related potential (AERP), and explore the accuracy of hearing thresholds by using ASSR and AERP and the clinic forensic value. METHODS: Thirty seven ears were tested with pure-tone audiometer, 40Hz AERP and ASSR, respectively. All the volunteers in our study were awake during 40 Hz AERP test and ASSR test. RESULTS: Thresholds acquired with ASSR and 40Hz AERP test had a close correlativity and showed higher than those acquired with PTA test. There was no significant difference between the accuracy of ASSR and 40Hz AERP in estimating pure-tone thresholds. CONCLUSION After determining the correct value, ASSR can be used directly to evaluate hearing loss objectively.
Acoustic Stimulation ; Adult ; Audiometry, Evoked Response ; Audiometry, Pure-Tone/methods* ; Auditory Threshold ; Evaluation Studies as Topic ; Evoked Potentials, Auditory, Brain Stem/physiology* ; Female ; Hearing Loss, Sensorineural/physiopathology* ; Humans ; Male ; Middle Aged ; Predictive Value of Tests ; Sleep/physiology* ; Wakefulness ; Young Adult

BACKGROUND AND OBJECTIVEProton magnetic resonance spectroscopy (MRS) of the liver in vivo is in experimental phase. MRS observation on liver cancer after transcatheter arterial chemoembolization (TACE) has seldom been reported. This study was to investigate the value of MRS in assessing the metabolic changes of hepatocellular carcinoma (HCC) after TACE.

METHODSTwenty-five consecutive patients with pathologically-confirmed HCC received 1H MRS of all hepatic lesions using 1.5T whole body MR scanner before TACE and at 3-10 days after TACE. Choline-to-lipid (Cho/Lip), glucogen/glucose-to-lipid (Glu/Lip), and glytamine/glutamate-to-lipid (Glx/Lip) ratios were measured and analyzed statistically.

RESULTSThe Cho/Lip, Glu/Lip, and Glx/Lip ratios were 0.21 +/- 0.08, 0.11 +/- 0.05, 0.28 +/- 0.10 before TACE, respectively, and were 0.10 +/- 0.08, 0.07 +/- 0.07, 0.18 +/- 0.12 after TACE, respectively, with significant differences (P < 0.05).

CONCLUSIONSUsing MRS can evaluate the early metabolic responses of HCC to TACE.

Adult ; Aged ; Carcinoma, Hepatocellular ; metabolism ; therapy ; Chemoembolization, Therapeutic ; Choline ; metabolism ; Female ; Glucose ; metabolism ; Glutamic Acid ; metabolism ; Glutamine ; metabolism ; Glycogen ; metabolism ; Humans ; Lipids ; analysis ; Liver Neoplasms ; metabolism ; therapy ; Magnetic Resonance Spectroscopy ; methods ; Male ; Middle Aged