Objectives/Hypotheses:
An eyewear mounted visual display (“User-worn see-through display”) projecting an artificial horizon aligned with the user's head and body position in space can prevent or lessen motion sickness in susceptible individuals when in a motion provocative environment as well as aid patients undergoing vestibular rehabilitation. In this project, a wearable display device, including software technology and hardware, was developed and a phase I feasibility study and phase II clinical trial for safety and efficacy were performed.

Study Design:
Both phase I and phase II were prospective studies funded by the NIH. The phase II study used repeated measures for motion intolerant subjects and a randomized control group (display device/no display device) pre–posttest design for patients in vestibular rehabilitation.

Methods:
Following technology and display device development, 75 patients were evaluated by test and rating scales in the phase II study; 25 subjects with motion intolerance used the technology in the display device in provocative environments and completed subjective rating scales, whereas 50 patients were evaluated before and after vestibular rehabilitation (25 using the display device and 25 in a control group) using established test measures.

Results:
All patients with motion intolerance rated the technology as helpful for nine symptoms assessed, and 96% rated the display device as simple and easy to use. Duration of symptoms significantly decreased with use of the technology displayed. In patients undergoing vestibular rehabilitation, there were no significant differences in amount of change from pre- to posttherapy on objective balance tests between display device users and controls. However, those using the technology required significantly fewer rehabilitation sessions to achieve those outcomes than the control group.

Conclusions:
A user-worn see-through display, utilizing a visual fixation target coupled with a stable artificial horizon and aligned with user movement, has demonstrated substantial benefit for individuals susceptible to motion intolerance and spatial disorientation and those undergoing vestibular rehabilitation. The technology developed has applications in any environment where motion sensitivity affects human performance. Laryngoscope, 121:S17–S35, 2011

Controlling motion sickness and spatial disorientation and enhancing vestibular rehabilitation with a user‐worn see‐through display

A polypoid, pedunculated tumour of the left palatine tonsil was incidentally detected in a 42-year-old female. It was composed of mature fat and was covered by a nonkeratinizing squamous epithelium with an underlying rim of fibrous tissue. The literature on tonsillar lipoma is reviewed and the differential diagnosis of polypoid lesions of the tonsil is discussed.

Polypoid lipoma of the palatine tonsil

Benign tumours of the tonsils are rare. Only a few cases of tonsillar lipoma have been previously reported. The case of a pedunculated polypoid lipoma of the palatine tonsil in a 44-year-old Japanese woman is presented. The 'polyp' was excised and an histopathological examination was carried out. The 'polyp' contained dilated lymphatics in the dense fibrous connective tissue beneath the overlying mucosal epithelium and below the mature fat tissue with intervening strands of fibrous tissue.

Tonsillar lipoma: a case report.

Electrical unipolar monoaural stimulation of the labyrinth led to body sway mainly on a frontal plane in normal human subjects in a standing position. Early and late stages of response with latencies of 120–200 and 200–500 msec respectively changing in size in accordance with conditions of visual control were distinguished in the stabilographic response. Maximum response was recorded when the eyes were closed. Response declined upon opening the eyes, fixing the gaze on a static target, and with visual feedback according to stabilograms. The early and late components declined by 10–20 and 50–70% respectively in all cases. Fixing the gaze, in darkness, on an illuminated light spot stationary in relation to the head had no effect on level of response. Once the expected direction of body sway had been imparted, a significant and almost identical decrease of 70–80% in both components took place with the gaze fixed, however. Early and late components of vestibulomotor response are thought to be mediated by regulatory mechasisms with differing time courses and functional connections.

Changes in vestibular postural response determined by information content of visual feedback

Hamartomatous polyps of the palatine tonsil are very rare. They have been variously termed as a lymphangiectatic fibrous polyp, lipoma, pedunculated tonsil etc. in the English literature. We present here a case of hamartomatous polyp of the tonsil occurring in a 32-year-old male who presented with bilateral enlarged palatine tonsils with recurrent tonsillitis. Surgical excision showed two pale brown nodular tissue bits, larger measuring 4×3×1 cm and smaller measuring 3.5×2.5×1.5 cm. An irregular pedunculated polypoidal tissue measuring 1.5×1×0.8 cm was seen attached to the smaller mass, the cut surface of which showed pale white, lobulated areas. On histological examination, the polyp showed lining by stratified squamous epithelium and was composed of fibrocollagenous stroma with many dilated blood vessels, adipocytes, subepithelial lymphoid aggregates and benign mucinous glands suggestive of a hamartomatous polyp. Both tonsils showed features of chronic tonsillitis.

A Pedunculated Hamartomatous Polyp of the Palatine Tonsil

Benign tumors of the pharynx are very rare. The authors report on the remarkable case of a tonsillar angiofibrolipoma.

Angiofibrolipoma of the tonsil

The nystagmus of 20 normal subjects was compared by means of the rotatory test in the dark, in respect of visual fixation, and with stabilization of vision. Visual fixation was tested by means of a small lamp placed at a distance of 40 cm in front of the eyes of the subject. This point of fixation was attached to the rotating chair. Stabilization of vision was attained through a box placed above the head of the test person. This box - covering the whole visual field - moved synchronously with the rotating chair. Contrary to the test with fixation, the eye received no information about the real movement. The question was whether there would be any differences between the fixation test and the stabilization of vision. In both test conditions, fixation overrides the vestibular stimulus and results in suppressing both per- and postrotational nystagmus. This proves that the foveal vision and not peripheral vision is responsible for the suppression of fixation.

Ch. Krausen

Papers

Angiofibrolipoma of the tonsil

Effect of stabilization of the visual field on rotatory testing