1. Spatial Disorientation
Clinical Vignette:
Spatial Disorientation
Good Morning.
MAJ Tim Cho and LCDR Jim Gilson
Occupational/Aerospace Medicine Residents

2. MAJ TIM CHO, LCDR JIM GILSON AND ALL OTHERS INVOLVED IN THE PLANNING, DEVELOPMENT, AND PRESENTATION OF THIS LIVE CME EDUCATIONAL ACTIVITY PROVIDE THE FOLLOWING DISCLOSURE INFORMATION:
“NOTHING TO DISCLOSE”
We have nothing to disclose.

3. OUTLINE Introduction Clinical Presentation Discussion References
History
Differential Diagnosis
Review of Systems
Physical examination
Investigations
Patient Course
Discussion
References
Questions/Comments

4. INTRODUCTION
Spatial Orientation relies on visual cueing, a functioning vestibular organ system, and proprioception
Spatial disorientation occurs when the pilot’s perception of direction (attitude) is miscued to the actual surrounding
Somatogyral (semicircular canals) and somatogravic (utricle and saccule) illusions occur
This is a clinical vignette that teaches us to appreciate the complexities of Spatial Disorientation
SD is a known phenomenon and has 3 components, e.g. visual, vestibular organ and proprioception There are 2 types of illusions e.g., somatogyral and somatogravic The clinical presentation of this patient did not follow the textbook allowing both of us as first year residents to appreciate that complexities of SD.

5. CLINICAL PRESENTATION (History)
31 year old active duty
Apache instructor pilot presents with a chief complaint of a tumbling sensation when the air- craft is in pitch. He is a reliable historian and recollects the initial and transient sensation when deployed 2 years ago, however upon PCS’ing to Fort Rucker, AL, the sensation has now become a distraction when flying, resulting in him being more anxious.
Slide 5: History -31 year old active duty Apache instructor pilot presents with a chief complaint of a tumbling sensation when the aircraft is in pitch. He is a reliable historian and recollects the initial and transient sensation when deployed 2 years ago however upon PCS’ing to Fort Rucker AL, the sensation has now become a distraction when flying, resulting in him being more anxious. Pertinent (+): sensation of tumbling with aircraft in pitch, anxiety Pertinent (-): no acute illness, no drug or ETOH history, no blurry vision/double vision, no ringing of the ears, no musculoskeletal weakness, no cardiac history, no medication history, no psychiatric history, no motion sickness history, no disorientation with turning aircraft

6. CLINICAL PRESENTATION (History)
Pertinent (+): sensation of tumbling when the aircraft is in pitch, anxiety, headaches
Pertinent (-): no acute illness, no drug or ETOH history, no blurry vision/double vision, no ringing of the ears, no musculoskeletal weakness, no cardiac history, no medication, psychiatric or motion sickness history, no disorientation when rotating
Slide 5: History -31 year old active duty Apache instructor pilot presents with a chief complaint of a tumbling sensation when the aircraft is in pitch. He is a reliable historian and recollects the initial and transient sensation when deployed 2 years ago however upon PCS’ing to Fort Rucker AL, the sensation has now become a distraction when flying, resulting in him being more anxious. Pertinent (+): sensation of tumbling with aircraft in pitch, anxiety Pertinent (-): no acute illness, no drug or ETOH history, no blurry vision/double vision, no ringing of the ears, no musculoskeletal weakness, no cardiac history, no medication history, no psychiatric history, no motion sickness history, no disorientation with turning aircraft

7. CLINICAL PRESENTATION (Differential Diagnosis)
vertigo
benign paroxysmal positional vertigo
migraine headaches
anxiety
vestibular neuronitis
labyrinthitis
acoustic neuroma
inner ear anomaly
Slide 7: DDx: motion sickness: acoustic neuroma: meniere’s disease/vertigo: inner ear/vestibular organ trauma: vestibular neuronitis benign paroxysmal positional vertigo migraines: cardiac: medication: anxiety/mental health psych:

8. CLINICAL PRESENTATION (Review of Systems and Physical Exam)
HEENT: chronic wisdom teeth pain
Cardiovascular: unremarkable
Pulmonary: unremarkable
Gastrointestinal: unremarkable
Genitourinary: unremarkable
Skin: unremarkable
Musculoskeletal: unremarkable
Neurological: positional vertigo
Psychiatric: unremarkable
General Appearance: WD, WN M in NAD
Cranial II- XII: WNL
Sensation: WNL
Motor: WNL
Coordination/Cere-bellum: WNL
Gait and Stance: WNL
Reflexes: WNL

9. CLINICAL PRESENTATION (Investigations)
MRI, Brain
Impression: Normal
MRI, Internal Auditory Canals
Impression: Normal
MSDD
(+) abnormal somatogravic perception
(-) abnormal somatogyral perception
Slide 8: Physical Examination General Appearance: well groomed, WD WN M in NAD Cranial II – XII: WNL Sensation: WNL Motor: WNL Coordination/Cerebellum: WNL Gait and Stance: WNL Reflexes: WNL

10. CLINICAL PRESENTATION (MSDD)
Centrifugal
Force
Gravity
Resultant
Gravito-inertial
Subject
Control
Slide 9: Investigations -Multi-station Spatial Disorientation Device (MSDD)* literature review Control: reports pitch up at +30 degrees Subject/Pilot: reports no change in linear acceleration in the vertical MSDD spinning at 120 degrees/sec -Control was able to articulate an angular pitch of 30 degrees. -Subject did not sense any change in direction despite increased linear acceleration towards the vertical.

11. CLINICAL PRESENTATION (Patient Course)
April 2014:
ENT/Otolaryngology Examination
July 2014:
NAMI Neurology examination
MSDD
August 2014:
Battalion staff
Restricted flying w/IP
December 2014:
Eye Movement De-sensitization and Reprocessing (EMDR) therapy,
Wisdom teeth pulled out
Slide 10: Patient Course April 2014: ENT Consult July 2014: NAMI Neurology Consult July 2014: MSDD August 2014: Battalion Staff, restricted flying with another IP Dec 2014: Psychiatric Eye Movement De-sensitization and Reprocessing (EMDR)

12. DISCUSSION Lesson Learned On-going case
Leadership support combined with medical management is a viable course of action
Tri-service waiver process
Vertigo
The way forward
Additional cueing to close the gap between perceived and true orientation of pilot and environment
Slide 11: Discussion Lesson learned: This is an on-going case that involves a collective effort from the medical community as well as the aviation community. Leadership support while undergoing rehabilitation is an ideal and viable course of action. Waiver process: A precise diagnosis is not always possible in cases of vertigo, but the more specific a diagnosis then the easier to determine waiverability. Army Navy Air force CAMI The way forward: In addition to the current management strategy, desensitization should also include consider Spatial disorientation scenarios for pilots to experience, introduce tactile and 3-D audio to assist as additional cueing in order to provide a true orientation for the aviator.

13. AEROMEDICAL WAIVERS (Vertigo) ARMY NAVY AIR FORCE CAMI
Waiver: -provide diagnostic information Comments: -Otolaryngology, and Neurology consults -Audiogram evaluation -AMS
Waiver: -provide diagnostic information
Comments: -Otolaryngology consult -Audiogram evaluation -AMS -Vestibular tests -Vestibular rehabilitation therapy
Waiver: -none granted
Comments: -vestibular neuronitis is the exception -AMS, labs, tests, and Otolaryngology consult
Comments: -Requires FAA decision -Neurologic tests -medications, if any
Waiver process: A precise diagnosis is not always possible in cases of vertigo, but the more specific a diagnosis then the easier to determine waiverability. Army Navy Air force CAMI

14. REFERENCES
Davis, J. R., Johnson, R. & Stepanek, J. (4th ed.). (2008). Fundamentals of aerospace medicine. Lippincott Williams & Wilkins. Federal Aviation Administration. (n.d.). Aerospace medicine dispositions. Retrieved from United States Airforce. (n.d.). Air force waiver guide. Retrieved from United States Army. (n.d.). Flight surgeon’s aeromedical checklists & references. Retrieved from United States Navy. (n.d.). Aeromedical reference and waiver guide. Retrieved from *Special thank you to, CAPT(ret.) Rupert and Casey

15. Questions? Comments?