1. Characteristics of Congenital Hearing Loss Barbara S. Herrmann, Ph.D. CCC-A Audiology Department Massachusetts Eye and Ear Infirmary Harvard Medical School

2. Examine outcomes of UNHS For one metropolitan nursery: What types/degrees of hearing loss are being identified in newborns referred by UNHS What happens to those hearing losses over the first few months/years

3. My UNHS Background:

4. Data presented: From UNHS program at Massachusetts General Hospital Initiated NICU screening in 1981, UNHS in 1997 Follow-up evaluation at Massachusetts Eye and Ear Infirmary Audiology Department scheduled within 1 to 3 weeks of hospital discharge If hearing loss, usually next evaluation at 4 months of age

5. UNHS Flow in Massachusetts Hearing Screen Audiologist Supervise EBC Notify Parent Pediatrician Notify Parent Pediatrician Make F/U Appt Pass Refer Discharge DPH Pass Refer DPH Parent Liason Keep F/U Appt Phone Call to Parent

6. Critical Elements for Success Hearing Screen Audiologist Supervise EBC Notify Parent Pediatrician Notify Parent Pediatrician Make F/U Appt Pass Refer Discharge DPH Pass Refer DPH Parent Liason Keep F/U Appt Phone Call to Parent 1 3 2 4 5

7. Screening Protocol at MGH ALGO Infant Hearing Screeners (ALGO I to ALGO 3i) Audiologists or Technicians 35 dB HL shaped-click at 37/sec over 25 msec analysis time. Custom ear couplers. Electrode montage; Vertex (+), Nape (-), Forehead (ground). Single Screen

8. All MGH Nursery: 2000 to 2005 N=21,613 babies

9. MGH Level 1 N=19,252 MGH Level 3 N=1,371 MGH Statistics by Nursery Level

10. Follow-up between 1 and 4 weeks after discharge

11. Bone-Conduction Right Ear Threshold Left Ear Threshold AER Estimated Audiogram

14. First follow-up test N=393 of 455 refers (12% transferred or lost to follow-up) Normal hearing = AER thresholds of 20 dB HL or better

15. First follow-up by refer type Bilateral RefersUnilateral Refers

16. Type of Neonatal Hearing Loss Percent of Babies with Hearing Loss ( N=135) Incidence of Hearing Loss overall - 0.6% Incidence of sensorineural loss – 0.15% 60% bilateral loss; 40% unilateral loss

17. Degree of Hearing loss: Classified by threshold at 2000 Hz toneburst Classification rules: Normal: 20 dB HL or better at 2000 and 4000 Hz Borderline: 25 db HL Mild: 30 to 40 dB HL Moderate: 45 dB to 65 dB HL Severe: 75 to 85 dB HL Profound: 90 dB HL or greater

18. No response at 102 dB HL BorderlineMild ModerateSevere Profound Range of thresholds for each degree

19. Degree of Hearing Loss: all loss ears N=215 ears 23%28%32%5%12% 51% of refers have 2000 Hz thresholds between 25 and 40 dB HL

20. Degree of Hearing Loss: by type N=215 ears 3% 21% 20% 3% 10% 20% 7% 12%2% 65% conductive/unknown type 35% known sensorineural component

21. Further details: Unknown or type not determined Conductive hearing losses Sensorineural / mixed hearing loss Insight into current issues

22. Unknown/ Type not determined

23. Degree of loss for Unknown/ Type not determined 56%20%18% 3% N=66 ears

24. Primarily symmetric Left ear Right ear

25. Conductive hearing loss Right masked bone

26. Conductive hearing loss 10%46%41% 3% N=71 ears

27. Again, primarily symmetric Left ear Right ear

28. Conductive and Unknown ears similar, so have grouped them 3% 21% 20% 3% 10% 20% 7% 12%2% 65% of all loss are conductive or unknown origin: 41% of those are mild or better

29. What have we learned About 60% of ears with conductive or type not determined hearing loss identified within 1 month of newborn screen have mild or borderline degree of loss. Most of the babies have similar degrees of loss in each ear

30. Sensorineural / Mixed Losses

31. Sensorineural / Mixed Loss Ears 8% 20%36% 9%28% N=76 ears

32. Again, mostly symmetric

33. What have we learned 66% of ears with sensorineural hearing loss identified within 1 month of newborn screen have moderate hearing losses or better. 30% of sensorineural hearing loss identified by UNHS have hearing thresholds better than 40 dB HL

34. What happens over time…. Infants scheduled for another AER evaluation three months after initial test After that usually seen at 3 month intervals using behavioral audiometry Many with borderline hearing do not keep appointment Have re-evaluation data for 65 of 135 infants

35. Sensorineural / Mixed Losses N=65 babies 46% 26% 22% 7% 9% 82% 9% Most conductive losses resolve to normal within 3 months Most sensorineural loss do not change

36. Questions that have arisen in UNHS Are we identifying mild losses with ABR? What about unilateral refers with bilateral loss? Will any screening technique catch all losses? Should we follow unilateral refers?

37. Are we identifying mild losses with ABR? 8% 20%36% 9%28% N=76 ears

38. Yes First follow-up at 2 days, now 18 months hearing stable First follow-up at 3 days, now 7 years hearing stable Bilateral Refer

39. What about unilateral refers with bilateral loss? 3 cases of sensorineural/mixed loss on first follow-up in this cohort

40. Case 1 and Case 2 No response left ear at 85 dB HL Identified at 3 weeks, now 3 years old Hearing stable Identified at 6 weeks, now 12 months Hearing stable

41. Case 3 First AER Follow-up AER Which was correct – the screen or first follow-up bone?

42. Will any screening technique catch all losses? ABR bilateral refers; present OAEs

43. First follow-up by refer type Bilateral RefersUnilateral Refers Should we follow unilateral refers?

44. Yes Unilateral Refer Age 6 months First Behavioral Age 1 year

45. YES Age 2.6 years Age 3.5 years

46. Things to keep in mind….

47. Fluctuating conductive always an issue in follow-up studies 3 weeks of age 5 months of age

48. Fluctuating conductive always an issue in follow-up studies 5 months of age8 months of age

49. Fluctuating conductive always an issue in follow-up studies

50. Lots of confusion over earphones….. ALGO ear coupler has the least variation from baby to baby than any earphone Voss and Herrmann 2005

51. What we have learned: 66% of bilateral refers have hearing loss at about one month 80% of unilateral refers have normal hearing at about 1 month. About 60 to 65% of ears with hearing loss are conductive. About 60% of ears with conductive or type not determined hearing loss identified within 1 month of newborn screen have mild or borderline degree of loss. 66% of ears with sensorineural hearing loss identified within 1 month of newborn screen have moderate hearing losses or better. 30% of sensorineural hearing loss identified by UNHS are borderline of mild (hearing thresholds better than 40 dB HL) Most of the babies have similar degrees of loss in each ear

52. What else... Almost half of the conductive hearing losses are normal by 3 months of age. Most sensorineural hearing losses do not change over first few years. We are identifying mild losses with ABR. Unilateral refers with bilateral loss tend to be borderline cases No current screening technique catch all losses; one must chose which to miss. We should follow unilateral refers