The Effect of Chinese Herbal Medicine as an Adjuvant Therapy in the Treatment of Traumatic Anosmia

The Effect of Chinese Herbal Medicine(Tailored Guizhi Decoction) as an Adjuvant Therapy in the Treatment of Traumatic Anosmia

Objective: To investigate the effect of Chinese herbal medicine (CHM) as an adjuvant therapy in the treatment of traumatic anosmia. Methods: Patients with a clear history of loss of smell after head injury, and whose phenyl ethyl alcohol (PEA) odor detection threshold remained -1 after treatment with steroid, zinc, and olfactory training (OT) for one month, were included in this study between September of 2018 and November of 2020. They were randomly divided into 2 groups, with patients in the CHM group taking CHM (tailored Guizhi decoction) and performing OT, and those in the OT group receiving OT only for 6 months. After 3 months' and 6 months' treatment, the olfactory function was evaluated by both the PEA threshold test and the traditional Chinese version of the University of Pennsylvania Smell Identification Test (UPSIT-TC). Magnetic resonance imaging was performed to measure the volume of olfactory bulbs after 6 months' treatment.

Chinese herbal medicine, Guizhi decoction, Olfactory training, Phenyl ethyl alcohol threshold test, Traumatic anosmia, University of Pennsylvania Smell Identification Test

Treatment with steroid, zinc, and olfactory training for one month. And then, take CHM(Chinese herbal medicine) (tailored Guizhi decoction) and perform OT(olfactory training) for 6 months

Treatment with steroid, zinc, and olfactory training for one month. And then, perform OT(olfactory training) only for 6 months.

Tailored guizhi decoction powder is a compound Chinese herbal medicine which contains 7.0g of guizhi, 1.5g of chuanxiong, 1.5g of zhimu, 1.5g of xinyi, 0.3g of mahuang, 1.0g of baizh, 2.0g of jili, 1.5g of fuling, and 1.0g of danshen.

Four odorant bottles of PEA, lemon, eucalyptus, and clove oils were given. Patients were instructed to sniff the liquid in each bottle for 10 seconds, twice a day.

The PEA threshold test consists of different concentrations of a rose-like PEA odorant to measure the odor threshold. A 2-alternative forced-choice single-staircase procedure is used in the PEA test.

The PEA threshold test consists of different concentrations of a rose-like PEA odorant to measure the odor threshold. A 2-alternative forced-choice single-staircase procedure is used in the PEA test.

UPSIT-TC is an odor identification test that is modified from the North American version of University of Pennsylvania Smell Identification Test(UPSIT). In the UPSIT-TC, 8 Odorants have been replaced to reflect the culture of the test-takers [20]. The UPSIT-TC is composed of 40 tests. In each test, an odorant is embedded in microcapsules and positioned on the brown bottom strips of the test page. The patient scratches the strip with a pencil tip to release the odorant. Then he or she sniffs the released odorant and chooses from a set of 4 odor descriptors to identify the odorant. The test is scored as the number of odors identified correctly

UPSIT-TC is an odor identification test that is modified from the North American version of University of Pennsylvania Smell Identification Test(UPSIT). In the UPSIT-TC, 8 Odorants have been replaced to reflect the culture of the test-takers [20]. The UPSIT-TC is composed of 40 tests. In each test, an odorant is embedded in microcapsules and positioned on the brown bottom strips of the test page. The patient scratches the strip with a pencil tip to release the odorant. Then he or she sniffs the released odorant and chooses from a set of 4 odor descriptors to identify the odorant. The test is scored as the number of odors identified correctly

MRI was performed to measure the volume of olfactory bulbs (OB) at the end of the treatment using a 1.5-Tesla Exite MRI system (GEMS, Milwaukee, WI, USA) with a quadrature head coil. The imaging pulse sequences included axial T1-weighted images, FLAIR images, along with axial and coronal T2-weighted fast spin-echo images. Contrast-enhanced T1-weighted images with axial and coronal sections were acquired. After a sagittal localizing scan, 2-2.5-mm-thick T2-weighted coronal and sagittal (both TR = 5,000 ms, TE = 106 ms, NEX = 2, Matrix = 256 9 256) images without an interslice gap were taken with a 12-cm field of view, as per the standardized protocol for OB analysis. OB volumes were measured using Mimics Medical 21.0 (Materialise, Leuven, Belgium).

Inclusion Criteria: a clear history of loss of smell after an episode of head injury PEA threshold was -1, which is assumed to be anosmic Exclusion Criteria: One month later, they received birhinal and unirhinal PEA threshold tests. Any patient whose birhinal or unirhinal threshold was below -1 was excluded from the study.