BACKGROUND: Currently, Army aircrews needing refractive correction are issued the HGU-4/P aviator spectacles. However, a recently published survey found dissatisfaction with the current spectacle frame. The Aircrew Flight Frame (AFF) has been used by the Air Force for over 14 yr, with the AFF-OP (Operational) style used the longest. The purpose of this study was to evaluate AFF-OP performance and compatibility among U.S. Army aircrew under operational conditions.METHODS: At 1-, 6-, and 12-wk intervals, 73 Army aircrew members wore the AFF-OP eyewear and completed a Likert scale survey. There were 14 outcome measures surveyed, with the main outcome measure being frame preference.RESULTS: The AFF-OP was preferred significantly more than the HGU-4/P spectacle. Overall, 94% of aircrew responses preferred the AFF-OP and the three highest subjective reasons for AFF-OP preference were: 1) comfort around the ears without helmet or headset; 2) comfort around the ears with helmet or headset; and 3) the effect on ear cup seal. There were no statistically significant differences in responses over the three surveyed time intervals.DISCUSSION: Army aviation aircrew preferred the AFF-OP over the current HGU-4/P spectacles. Two of the top three highest subjective reasons for AFF-OP preference coincided with two of the top three operational eyewear problems reported in the recently published survey. If Army aircrew do not wear their issued eyewear, they may purchase their own frame “out of pocket.” However, this can lead to use of a frame that has not been tested for compatibility and may compromise performance of aircrew life support equipment.Walsh DV, Jurek GM, Capó-Aponte JE, Riggs DW, Ramiccio JA. Assessment of an alternative army aircrew eyewear. Aerosp Med Hum Perform. 2015; 86(12):1014–1019.

BACKGROUND: Personnel responding to a distressed submarine incident require information on likely casualty levels and the severity and progression of decompression illness (DCI). Recompression may not be immediately available. First aid oxygen (FAo₂) can be administered; however, there is no direct evidence of its efficacy in this scenario.METHODS: Trials were conducted between 2004 and 2006. Goats exposed to raised pressure for 24 h (‘saturation’) were either returned directly to atmospheric pressure (Phase A, N = 40) or exposed to simulated submarine escape at a depth of 656 ft (200 m; assumed seawater density = 1019.72 kg · m⁻³; Phase B, N = 39). The pressure during saturation was selected to provoke 50% DCI. Cases of DCI were randomly assigned to receive FAo₂ or air.RESULTS: DCI cases were: limb pain in 39 subjects, neurological in 6, respiratory in 4, and pulmonary barotrauma in 1 subject. In Phase A, 5/12 subjects in the FAo₂ group and 0/11 in the air control group achieved permanent resolution of DCI. In Phase B, 6/8 subjects in the FAo₂ group and 5/8 in the air control group achieved permanent resolution. In both Phases, levels of venous gas bubbles reduced sooner with FAo₂. Of three cases of neurological DCI receiving FAo₂, two showed permanent resolution. In total, four cases of respiratory DCI occurred; none of these resolved, with three being treated with FAo₂ and one in the air control.DISCUSSION: Oxygen can be an effective first aid measure for DCI following submarine escape. However, it should not be used as a replacement for recompression therapy.Loveman GAM, Seddon FM, Jurd KM, Thacker JC, Fisher AS. First aid oxygen treatment for decompression illness in the goat after simulated submarine escape. Aerosp Med Hum Perform. 2015; 86(12):1020–1027.

INTRODUCTION: This study investigated whether the timing of activation affects the utility of an emergency underwater rebreather unit (RBU) when submerged in cold water.METHOD: On two successive occasions, 16 male UK Royal Marines were submerged in stirred water at 12.2°C for up to 78 s. The subjects were lowered (taking 18 s) into the water in a seated position and were instructed to take a large breath in, activate the unit, breath-hold for as long as possible, exhale into the unit, and breathe normally to and from the unit for the remainder of submersion. On one occasion the subjects were instructed to activate the RBU when the water reached chest height (Condition-1) and, on the other, prior to the feet entering the water (Condition-2). Measurements were made of the duration of breath-hold, rebreathing and submersion, exhaled oxygen and carbon dioxide concentrations, skin temperature, and heart rate.RESULTS: In 16 of the 32 submersions, the breath-hold was released before the subject became fully submerged and in 8 submersions the subject requested early withdrawal from the water. Mean (SD) breath-hold duration was 14.0 (13.8) s and the duration of rebreathing was 45.9 (21.9) s. The duration of breath-hold once completely submerged was longer in Condition-1 (9.1 s) than Condition-2 (4.1 s).CONCLUSIONS: The study indicates the RBU should be activated just before the mouth becomes submerged rather than before entering the water, and that the RBU will prolong underwater stay time, thereby increasing survival prospects.House CM, Shaw AM, Roiz de Sa DG. Rebreather unit to prolong underwater survival time. Aerosp Med Hum Perform. 2015; 86(12):1028–1033.

BACKGROUND: Remote-guidance (RG) techniques aboard the International Space Station (ISS) have enabled astronauts to collect diagnostic-level ultrasound (US) images. Exploration-class missions will likely require nonformally trained sonographers to operate with greater autonomy given longer communication delays (> 6 s for missions beyond the Moon) and blackouts. Training requirements for autonomous collection of US images by non-US experts are being determined.METHODS: Novice US operators were randomly assigned to one of three groups to collect standardized US images while drawing expertise from A) RG only, B) a computer training tool only, or C) both RG and a computer training tool. Images were assessed for quality and examination duration. All operators were given a 10-min standardized generic training session in US scanning. The imaging task included: 1) bone fracture assessment in a phantom and 2) Focused Assessment with Sonography in Trauma (FAST) examination in a healthy volunteer. A human factors questionnaire was also completed.RESULTS: Mean time for group B during FAST was shorter (20.4 vs. 22.7 min) than time for the other groups. Image quality scoring was lower than in groups A or C, but all groups produced images of acceptable diagnostic quality.DISCUSSION: RG produces US images of higher quality than those produced with only computer-based instruction. Extended communication delays in exploration missions will eliminate the option of real-time guidance, thus requiring autonomous operation. The computer program used appears effective and could be a model for future digital US expertise banks. Terrestrially, it also provides adequate self-training and mentoring mechanisms.Hurst VW IV, Peterson S, Garcia K, Ebert D, Ham D, Amponsah D, Dulchavsky S. Concept of operations evaluation for using remote-guidance ultrasound for exploration spaceflight. Aerosp Med Hum Perform. 2015; 86(12):1034–1038.

BACKGROUND: When an aircrew member is referred for otosclerosis, his flight fitness may be questionable. The objective of this retrospective study was to describe a case series of otosclerosis in an aircrew population and to discuss the decisions about their flight waivers.METHODS: There were 27 aircrew members who were referred to the ENT-Head and Neck Surgery Department of the National Pilot Expertise Center. Their medical files were retrospectively examined.RESULTS: Out of 16 patients who had surgery, 2 did not obtain a flight fitness waiver afterwards. Among the 14 who received waivers, 12 had no restrictions on their flight fitness. Among the nonoperated patients, 1 of 11 did not obtain a waiver. Seven patients were declared medically fit to fly without a waiver and three obtained a waiver.DISCUSSION: Fitness was based on auditory and balance statuses and the follow-up of these findings. A postoperative CT-scan and the operative report were used to determine the quality of stapes surgery. Professional speech audiometry in noise might be as interesting. The results made it possible to determine a patient’s fitness to fly with a waiver, which is more or less associated with restrictions. In our series, only 3 aircrew members out of 27 did not obtain a flight fitness waiver. The few published studies on the resumption of flight for patients who underwent surgery and our experience in France with similar waivers in commercial and military aviation suggest that under certain conditions and after relevant vestibulocochlear assessment, stapes surgery may allow for a safe recovery of aviation activity.Ballivet de Régloix S, Gauthier J, Pons Y, Maurin O, Genestier L, Kossowski M. Otosclerosis and fitness to fly. Aerosp Med Hum Perform. 2015; 86(12):1039–1045.

BACKGROUND: Parkinson’s disease is a progressive neurodegenerative disorder which is encountered in the pilot population and has clinical features that can impact on the flying role. This retrospective study reviewed the United Kingdom Civil Aviation Authority (UK CAA) experience of Parkinson’s disease. The aeromedical implications of the condition are discussed and the UK CAA policy for the certificatory assessment of pilots with Parkinson’s disease is described.METHODS: A search of the UK CAA medical records database from 1990 to 2015 identified 34 pilots with a diagnosis of Parkinson’s disease. Data was extracted for the class of medical certificate, time from first symptoms to diagnosis, age at diagnosis, the time from diagnosis to loss of certification and the reasons for loss of certification.RESULTS: Of 15 professional (Class 1) and 19 private (Class 2) pilots, the mean time from onset of symptoms to diagnosis was 36 and 19 mo, respectively. The mean ages at diagnosis were 55 and 59 yr, respectively. The mean interval from diagnosis to loss of certification was 21 (0-93) and 37 (0-84) mo, respectively. The reasons for loss of certification are considered.CONCLUSION: In the UK, pilots diagnosed with Parkinson’s disease may be granted medical certification depending on their functional ability and the side effect profile of medication. The aeromedical implications of Parkinson’s disease and the UK CAA policy for the certification of pilots with Parkinson’s disease are discussed.Jagathesan T, O’Brien MD. The aeromedical implications of Parkinson’s disease. Aerosp Med Hum Perform. 2015; 86(12):1046–1051.

BACKGROUND: Helicopter pilots are involved in a complex multitask activity, implying overuse of cognitive resources, which may result in piloting task impairment or in decision-making failure. Studies usually investigate this phenomenon in well-controlled, poorly ecological situations by focusing on the correlation between physiological values and either cognitive workload or emotional state. This study aimed at jointly exploring workload induced by a realistic simulated helicopter flight mission and emotional state, as well as physiological markers.METHOD: The experiment took place in the helicopter full flight dynamic simulator. Six participants had to fly on two missions. Workload level, skin conductance, RMS-EMG, and emotional state were assessed.RESULTS: Joint analysis of psychological and physiological parameters associated with workload estimation revealed particular dynamics in each of three profiles. 1) Expert pilots showed a slight increase of measured physiological parameters associated with the increase in difficulty level. Workload estimates never reached the highest level and the emotional state for this profile only referred to positive emotions with low emotional intensity. 2) Non-Expert pilots showed increasing physiological values as the perceived workload increased. However, their emotional state referred to either positive or negative emotions, with a greater variability in emotional intensity. 3) Intermediate pilots were similar to Expert pilots regarding emotional states and similar to Non-Expert pilots regarding physiological patterns.DISCUSSION: Overall, high interindividual variability of these results highlight the complex link between physiological and psychological parameters with workload, and question whether physiology alone could predict a pilot's inability to make the right decision at the right time.Gaetan S, Dousset E, Marqueste T, Bringoux L, Bourdin C, Vercher J-L, Besson P. Cognitive workload and psychophysiological parameters during multitask activity in helicopter pilots. Aerosp Med Hum Perform. 2015; 86(12):1052–1057.

BACKGROUND: Decompression sickness is an inherent occupational hazard that has the possibility to leave its victims with significant long-lasting effects that can potentially impact an aircrew’s flight status. The relative infrequency of this hazard within the military flying community along with the potentially subtle presentation of decompression sickness (DCS) has the potential to result in delayed diagnosis and treatment, leading to residual deficits that can impact a patient’s daily life or even lead to death.CASE REPORT: The patient presented in this work was diagnosed with a Type II DCS 21 h after a cabin decompression at 35,000 ft (10,668 m). The patient had been asymptomatic with a completely normal physical/neurological exam following his flight. The following day, he presented with excessive fatigue and on re-evaluation was recommended for hyperbaric therapy, during which his symptoms completely resolved. He was re-evaluated 14 d later and cleared to resume flight duties without further incident.DISCUSSION: The manifestation of this patient’s decompression sickness was subtle and followed an evaluation that failed to identify any focal findings. A high index of suspicion with strict follow-up contributed to the identification of DCS in this case, resulting in definitive treatment and resolution of the patient’s symptoms. Determination of the need for hyperbaric therapy following oxygen supplementation and a thorough history and physical is imperative. If the diagnosis is in question, consider preemptive hyperbaric therapy as the benefits of treatment in DCS outweigh the risks of treatment. Finally, this work introduces the future potential of neuropsychological testing for both the diagnosis of DCS as well as assessing the effectiveness of hyperbaric therapy in Type II DCS.Alea K. Identifying the subtle presentation of decompression sickness. Aerosp Med Hum Perform. 2015; 86(12):1058–1062.

BACKGROUND: Varicocele is quite common in the general population, affecting up to 15% of men. It is not considered disqualifying for the pilot’s training program of the Israeli Air Force as long as there are no related symptoms or associated pathologies. During combat flight, increased venous pressure due to acceleration forces and anti-G straining maneuvers, used to counteract high gravitational G forces, can theoretically aggravate the venous blood pooling in varicocele, leading to rupture.CASE REPORT: We describe a case of a young fighter-jet pilot presenting with a painful inguinal hematoma extending to the scrotum a day after participating in centrifuge training. Sonographic examination demonstrated dilated spermatic veins and intratesticular varicocele along with subcutaneous thickening of the scrotal wall consistent with hematoma.DISCUSSION: The effects of high G loads on blood flow in spermatic veins, and especially in varicocele, still need to be determined. Varicocele rupture has been described in relation to increased intra-abdominal pressure and could theoretically occur during anti-G straining maneuvers. Such an acute adverse event during combat flight can be detrimental to flight safety and the pilot’s well-being.Kampel L, Klang E, Winkler H, Gordon B, Frenkel-Nir Y, Shoam YE. Scrotal hematoma precipitated by centrifuge training ina fighter pilot with an asymptomatic varicocele. Aerosp Med Hum Perform. 2015; 86(12):1063–1065.

BACKGROUND: Stroke is a decidedly devastating event for any patient, but particularly for a military aviator in a single-seat aircraft. Incidence of acute ischemic infarct in men ages 25 to 29 ranges from 3.4 to 5.6/100,000. The neurological sequelae of stroke can have a lasting and profound impact on an aviator’s career. Literature review revealed a relatively small number of cases where stroke was attributable to cervical manipulation.CASE REPORT: A 29-yr-old male jet pilot with a 2-wk history of cervicalgia following a mountain bike ride performed self-manipulation of his neck at home following a visit to a chiropractor. He sustained an immediate onset of euphoria, nausea, dysarthria, vertigo, diploplia, and occipital headache, and was transported via ambulance to the nearest emergency department. The patient’s MRI/MRA imaging revealed a dissection of his right vertebral artery, as well as bilateral cerebellar infarcts. During the course of the following months, the patient’s residual symptoms included neck pain, headaches, disequilibrium, and quadrantanopia.DISCUSSION: The ability to recognize the symptoms of stroke and seek treatment in a timely manner are paramount and can drastically reduce the potential for permanent deficit. The evaluation of residual sequelae in military aviators who fly single-seat aircraft is of particular interest to aerospace medicine physicians when it comes time to return a pilot to flight duties. Additionally, the link between cervical manipulation and vertebral artery dissection leading to stroke remains equivocal, and further research is warranted.Mukherjee ST. Cervical manipulation leading to cerebellar stroke in a pilot. Aerosp Med Hum Perform. 2015; 86(12):1066–1069.

ABSTRACT: The paper “Body Mass Changes During Long-Duration Spaceflight” allows a comparison of devices, their application, results obtained and their interpretation from the two programs of such studies to date. There were significant differences in all aspects of the two programs which are briefly commented on here.Thornton W. Comments on body mass changes during long-duration spaceflight. Aerosp Med Hum Perform. 2015; 86(12):1070–1071.

Park B. You're the flight surgeon: white matter hyperintensities. Aerosp Med Hum Perform. 2015; 86(12):1075–1077.

Wolf SJ. You’re the flight surgeon: lateral epicondylitis. Aerosp Med Hum Perform. 2015; 86(12):1077–1080.