Intergroup differences of POI-8 outcomes in ST- and LT-cohort
Six weeks after parotidectomy, 77,2% of the ST-cohort characterized hypoesthesia as the most disturbing problem, followed by xerostomia (47.4%) and the appearance of the scar (45.6%). Facial palsy was posed as minor problem (87.7%). In the LT-cohort, hypoesthesia (54.1%), followed by fear of revision surgery (44.6%) and appearance of the scar (39.2%) posed the major problems. 95.9% of the patients described facial palsy not as problematic.
42.1% of ST-cohort characterized pain on the site of surgery significantly more problematic with the mean POI-8 score of 0.93 than LT-cohort with the mean POI-8 score of 0.34 (p = 0.002). 77% of LT-patients affirmed no pain or painful sensations 13 years after parotidectomy. Hypoesthesia improved significantly over the years but still posed a problem: 77.2% of ST-patients were disturbed by hypoesthesia six weeks after surgery with the mean POI-8 score of 1.86 and 54.1% of the LT-cohort still named sensation loss as a problem with the POI-8 mean score of 0.88 (p < 0.001).
The ST- and LT-cohort did not differ in POI-8 responses concerning scar (p = 0.07), facial palsy (p = 0.21), substance loss (p = 0.37), Frey’s syndrome (p = 0.64), xerostomia (p = 0.14) and anxiety of revision surgery (p = 0.73). There was a significant change in the mean score of POI-8 detectable (ST-POI-8 of 7.47, LT-POI-8 of 5.15; p = 0.04) (Figure 2).
In the ST-cohort, 64.9% of patients were - predominantly slightly - affected in disease-specific QOL after parotid surgery. 68.4% patients filled out to be “very satisfied” with operation results. In the LT-cohort, 27% of patients still described impairment after parotidectomy, thereof 4.1% as “severe”. There was a long-term satisfaction rate of 81.8%. Negligible doctor visits (6.8%)/days of incapacitation (2.7%) and no rehabilitative measures were documented in the LT-cohort
Intragroup differences in POI-8 outcomes in SLT-cohort
Six weeks after parotidectomy, 84.8% of the SLT-cohort characterized hypoesthesia as the most disturbing problem, followed by the appearance of the scar (54.5%) and pain (51,5%). Facial palsy posed the minor problem (87.9%). At 13 years follow-up, hypoesthesia still bothered 60.6% of them, but only 3% severely, as well as Frey’s syndrome (48,5%) and fear of revision (42,4%). No one suffered from facial palsy in the LT-cohort. In the meantime, from 6 weeks to 13 years after surgery, hypoesthesia (p < 0.001) and pain (p = 0.004) had significantly improved from patient’s perspective. Dissatisfaction with the scar (p = 0.13), appearance due to substance loss (p = 0.17), Frey’s syndrome (p = 0.36), xerostomia (p = 0.09), fear of revision surgery (p = 0.75) and facial palsy (p = 0.08) did not significantly ameliorate after surgery. The total score of POI-8 significantly decreased from the mean POI-8 score of 8.24 six weeks after surgery to the mean POI-8 score of 5.15 13 years after surgery, indicating higher overall satisfaction (p = 0.04; Figure 2).
Six weeks after parotidectomy, 72.7% of patients felt - mostly slightly – impaired by high satisfaction rate of 69.7%. In the long-term interval, 33,3% of patients felt impaired after parotid surgery, the satisfaction rate amounted 78.8%. No days of incapacitation, no rehabilitative measures and nearly no medical doctor visits (6.1%) were necessary in the last 6 months.
All group comparisons are graphically illustrated in Figure 3.
Preservation of the great auricular nerve (GAN)
Based on all available surgical reports (n = 98), 45.9% of the GAN could be technically preserved, 33.7% had been sacrificed and in 20.4% no information was found in the operation report.
All patients of the LT-cohort (n = 40; 23 men, 17 women), who documented a sensation loss in the POI-8 questionnaire, were contacted again and were asked about the location of the numbness. The area overlying the parotid gland and at the angle of the mandibule were slightly more affected than the area of auricle and along the anterior border of the sternocleidomastoid muscle (55% versus 45%). In general, the patients did not feel limited in QOL: the majority of the patients described the hypoesthesia as “marginal” (55%) or “slight” (35%), but 10% of them felt “moderately”/”severely” or “very severely” affected. Concerning this selected collective here (n = 40), there were no correlations between the nerve’s sacrifice, the second POI-8 item, the operation procedure (lateral vs. total) and the affected area detectable (p > 0.05). Sacrifice of the GAN was only associated with the second item of the POI-8 (hypoesthesia) in the ST-cohort (p = 0.028), not in the SLT- or LT-cohort, using chi-square test.