Pulmonary barotrauma during hookah diving: a case report.

When commercial sea harvesters have dive accidents, it is sometimes difficult to obtain an accurate dive history and make a definitive diagnosis. We report a sea harvest diver who dived to collect sea snails (Rapana venosa) by using a hookah dive system. He experienced mediastinal and subcutaneous emphysema due to interruption of breathing airflow. Thoracic computed tomography performed one year prior to the accident revealed paramediastinal subpleural blebs on both lung apices. Emphysema was resolved by administering normobaric oxygen.

Incidence of decompression sickness in hypobaric hypoxia training.

Simulated flight in a hypobaric chamber is a fundamental component in the physiological training of aviators. Although rare, there is always a risk of decompression sickness (DCS) in trainees during hypobaric hypoxia training. In this study we aimed to determine the incidence of altitude-induced DCS and the symptoms manifested in trainees and inside chamber observers (ICOs) during the training sessions. We retrospectively reviewed the records of DCS cases during the period of January 1, 2011, and October 1, 2018. The records of 6,657 trainees and 615 ICOs were evaluated. The gender distribution in 6,657 trainees was 6,578 (98.81%) male and 79 (1.19%) female. The numbers of DCS cases in trainees and ICOs were six (0.09%) and two (0.33%), respectively [(ICOs versus trainees - odds ratio (OR): 3.574; 95% CI 0.720-17.744; (p > 0.05)]. All ICOs were male; no DCS incident was observed among female trainees. Recompression treatments were applied on site, and complete recovery was achieved in all cases. Overall DCS incidence was found to be 0.11% among the 7,193 male subjects, which included trainees and ICOs. The higher incidence of DCS in ICOs was attributed to the physical activities performed at altitudes by ICOs. In such training, established instructions have to be strictly followed by physicians, ICOs and trainees. All trainees and ICOs should be aware of the symptoms and signs of DCS, and medical support including a recompression facility, should be provided on site during hypobaric hypoxia training.

Evaluation of fatal diving accidents in Turkey

In any kind of diving there is a risk of accidents, as the move from the topside environment to underwater can affect a diver's physiological and psychological condition. It is important to investigate dive accidents to clarify the causative factors and determine preventive measures. In this study, autopsy files of fatal dive accident cases were reviewed to evaluate demographic data, type of diving, purpose of dive, seasonal distribution, autopsy findings, and causes of death. We reviewed 56 fatal dive accident files from autopsy units in cities where dive activities are concentrated and from the archive of the Turkish Underwater Federation. Four cases were excluded from the study since we were unable to obtain autopsy reports. Of 52 cases there were 20 scuba divers, two surface-supplied divers and 30 breath-hold divers. The majority of cases involved males (94%). The average age of 50 cases was 38.6; age estimation for two cases could not be determined due to advanced putrefaction. Of these fatal dive accidents 75% took place over a period of six months between May and October. Drowning was recorded as the primary cause of death in these cases. X-ray imaging was used in four (8%) cases. A special autopsy technique was used for nine (17%) cases, to detect possible pulmonary barotrauma and arterial gas embolism. The forensic specialist who is planning to conduct the autopsy for a dive fatality should have knowledge and experience about dive physics and physiology as well as physiopathology of dysbaric injuries.

Eurasian Tunnel Project: the first saturation dives during compressed-air work in Turkey.

The Eurasian Tunnel is a 5.64-km crossroad tunnel that connects Europe and Asia. Located under the seabed for the first time, 3.34 km of the tunnel that crosses the Bosphorus was built by advanced tunneling techniques. An exclusively designed tunnel boring machine (TBM), which has an operating pressure of 11 bars and a diameter of 13.7 meters was used for boring the seabed tunnel. The deepest point was 106 meters below sea level. One bounce diving period and seven saturation diving periods were needed for the repair and maintenance of the TBM during the project. Total time spent under pressure was 5,763 hours. A saturation decompression chamber for four divers was used for the saturation interventions, and divers breathed trimix at storage and excursion depths. The longest saturation run was the second, with storage at 10 bars and excursions to 10.4 bars. Twenty-three professional divers who were all experienced in compressed-air work were assigned to work on the project. Four dive physicians provided medical support, which included screening of divers before and during the hyperbaric interventions as well as on-site supervision. There were no diving-related accidents. A minor hand trauma, an external otitis and occasional insomnia were non-diving-related health issues that occurred during saturation and bounce diving. To our knowledge, the Eurasian Tunnel was the first project to perform TBM repair operations at such depths under the seabed and the first saturation diving in Turkey. In this report, we aimed to share our experiences of hyperbaric medical consulting in support of this type of tunneling project.

Hyperbaric oxygen therapy for five days increases blood-brain barrier permeability.

This study aimed to explore the effects of hyperbaric oxygen (HBO2) on blood-brain barrier (BBB) integrity in rats, when administered for one (at 2.5 ATA, 3 HBO2 sessions a day) and five days (at 2.5 ATA, 3 HBO2 sessions a day for the first two days, and twice a day for the last three days). Horseradish peroxidase (HRP) was used to evaluate the BBB permeability. Superoxide dismutase (SOD) activity, glutathione (GSH) and malondialdehyde (MDA) levels were measured in the cerebral cortex and hippocampus regions. Frequent vesicles containing HRP reaction products were observed in capillary endothelial cells in the cerebral cortex and hippocampus of rats subjected to HBO2. The accumulation of HRP reaction products in these brain regions was significantly higher than that of control animals (P ⟨ 0.01). In animals that received HBO2, MDA levels (P ⟨ 0.01 for five days) and GSH (p ⟨ 0.05 for one day, and P ⟨ 0.01 for five days) were decreased in the cerebral cortex, whereas SOD activities slightly increased in this region. In animals that received HBO2 significant decreases in MDA (P ⟨ 0.05 for one day; P ⟨ 0.01 for five days) and GSH (P ⟨ 0.05 for five days) levels were observed in the hippocampus region, but SOD activities decreased in this region. We showed that HBO2 administered with the doses described above impaired BBB integrity in otherwise healthy rats. Therefore, we suggest that the results of this study should be taken into consideration when patients are exposed to HBO2 with the same doses.

Effect of hyperbaric oxygen treatment on pilonidal disease surgery.

Surgical excision and lay-open is a well-known technique for the treatment of sacrococcygeal pilonidal disease, which impairs a patient's quality of life considerably since wound healing takes a substantial amount of time. It is known that with this method total healing period is longer, but recurrence rate of the disease is lower. The beneficial effects of hyperbaric oxygen (HBO2) therapy on wound healing have been well established since it was first put into in clinical use. The purpose of this prospective randomized clinical trial was to investigate the effects of HBO2 therapy on wound healing in the patients who had sacrococcygeal pilonidal disease and surgical treatment. Total epithelialization times of 12 patients (Group 1) who received surgical intervention were compared with those of 10 patients who had surgical intervention and HBO2 therapy (Group 2). In both groups excised tissue volume, excised skin area, body mass index, blood hemoglobin, albumin levels, ages and duration of the complaints were recorded and there was no statistically significant difference in these parameters except albumin levels when compared. The complete epithelialization time was significantly shorter in Group 2 (50 ± 11 vs. 83 ± 18, p⟨0.001). We conclude that HBO2 had beneficial effects on wound healing, in the patients who had sacrococcygeal pilonidal disease and were treated with surgical excision applying lay-open technique.

Effects of topical nasal steroids and diclofenac on the nasal mucosa during hyperbaric oxygen therapy: a double-blind experimental study.

We aimed to evaluate nasal mucosal changes and efficiency of nasal steroids and diclofenac on nasal mucosa during hyperbaric oxygen (HBO) treatment. Forty adult Albino-Wistar rats were randomized into four groups. Group 1 (control group) (n = 10) not exposed to hyperbaric or enhanced oxygen concentrations; group 2 (HBO group) (n = 10) underwent only HBO treatment; group 3 (n = 10) received HBO and intranasal mometasone furoate (10 µl/day); group 4 (n = 10) treated with HBO and diclofenac sodium (10 mg/kg/day ip). Specimens of nasal mucosa were collected after sacrificing and dissection of animals. The specimens were processed for light microscopic evaluation, and then evaluated histopathologically for fibroblastic proliferation and inflammation. Regarding the scores of inflammation, the level of inflammation in the control group was significantly less severe than the other groups (p < 0.05). Evaluation of the fibrosis scores showed that the scores of both groups 2 and 4 were significantly increased (p < 0.05). There were no statistically significant differences between groups 2, 3, and 4 as for fibrosis and inflammation (p > 0.05). Chronic HBO treatment induced mild inflammation of the nasal mucosa. These effects cannot be prevented adequately by administration of nasal steroids and diclofenac.

Decompression sickness cases treated with recompression therapy between 1963 and 1998 in Turkey: review of 179 cases.

The purpose of this study was to review the cases diagnosed as decompression sickness (DCS) with recompression therapy treament between 1963 and 1998 in Turkey. The records of 179 cases were analyzed for age, gender, type of DCS, presenting signs and symptoms, time to onset of symptoms, time to recompression therapy, recompression table used, total number of treatments and outcomes. The diving depth on the day of injury ranged between 60 and 215 fsw (18 and 65 msw). The symptoms developed during ascent or within 10 minutes after surfacing in 47% of divers and within the first hour in 87% of the divers. The most frequent symptom was sensory loss in the extremities. The dive before the symptoms was a repetitive dive in 50% of the cases and the diagnosis was Type II DCS in 79% of these divers. Most of the divers (84%) received recompression therapy after a delay of more than 12 hours. Healing rate was 68% with the air recompression tables and 86% with the oxygen tables. Repetitive dives were associated with a higher incidence of Type II DCS than single dives (79% and 66%, respectively). The results using recompression tables with oxygen were more successful than the treatment with air tables.

Development of underwater and hyperbaric medicine as a medical specialty in Turkey.

Underwater and hyperbaric medicine focuses on diving physiology, prevention and treatment of health problems related to the exposure to high ambient pressure and therapeutic use of hyperbaric oxygen for several medical conditions. Adequate educational standards should be developed for physicians working in the field of underwater and hyperbaric medicine. In Turkey, underwater and hyperbaric medicine is one of the medical specialties. The history of underwater and hyperbaric medicine as a medical specialty is dated back to the 1960s. In this paper, we review standards and the development of underwater and hyperbaric medicine as a medical specialty in Turkey.

Hyberbaric oxygen increases atresia in normal & steroid induced PCO rat ovaries.

BACKGROUND: In this study, we investigated the effect of hyperbaric oxygen therapy (HBOT) on the morphology of estradiol valerate (EV) induced polycystic ovary (PCO) to find a new treatment modality for improvement of PCO. METHODS: The rats were divided into four groups. Group1, control; group 2, PCO group; group 3, PCO with HBOT group and group 4, normal ovary with HBOT. PCO was induced by a single intramuscular injection of 4 mg EV in adult cycling rats. Other rats with normal ovaries had oil injection as placebo. HBOT was applied to third and fourth groups for six weeks. Histopathologic evaluation of ovaries of all groups were performed & compared. RESULTS: Six weeks of HBOT was resulted in increase in follicular atresia, decrease in the number of primary, secondary, tertiary follicles and decrease in the number of fresh corpus luteum in normal rat ovary. HBOT on polycystic rat ovary, resulted in significant increase in atretic follicles which were already present. CONCLUSIONS: HBOT of six weeks itself, changed ovarian morphology in favor of atresia both in PCO group and control group. This result of aggravated follicular atresia after HBOT on EV induced PCO may be due to long-term exposure in our protocol which with this state seems to be inapplicable in the improvement of PCO morphology.

Post COVID-19 fitness to dive assessment findings in occupational and recreational divers.

INTRODUCTION: It is now known that COVID-19 has long term effects that may not correlate with clinical severity of disease. The known pulmonary and cardiovascular changes as well as thrombotic tendency could predispose to diving accidents. We aimed to investigate COVID-19 related changes that may cause disqualification from diving among divers who recovered from the disease. METHODS: Occupational and recreational divers who applied for fitness to dive (FTD) assessment after COVID-19 infection were included. Routine FTD assessments were performed. Details of COVID-19 history were evaluated. Lung computed tomography (CT) scans were advised if not previously performed or if there were COVID-19 related changes in previous scans. Divers with pathological findings were restrained from diving and followed prospectively. RESULTS: Forty-three divers were analysed. Thirteen divers were restrained from diving, all due to persistent COVID-19 related changes in lung CT. The prevalence of CT with at least one lung lesion was 68.2% at the time of diagnosis, 73.3% in the first three months after diagnosis and 19.2% later. The most common CT findings were glass ground opacities and fibrotic changes. Demographic characteristics and COVID-19 history of divers deemed 'unfit' were similar to those deemed 'fit'. CONCLUSIONS: Divers who recover from COVID-19 should undergo FTD assessments before resuming diving. A chest CT performed at least three months after diagnosis may be suggested.

A COVID-19 infection incidentally detected during hyperbaric oxygen treatment and preventive measures for COVID-19 transmission in a multiplace hyperbaric chamber.

INTRODUCTION: SARS-CoV-2 (COVID-19) was declared a global pandemic on 11 March 2020 and has become a serious threat to public health. As it can easily be transmitted through droplets and aerosols, there is an increased risk of transmission in enclosed environments such as hyperbaric oxygen treatment (HBOT) units if preventive measures are not taken. CASE REPORT: A 16-year-old female tested positive for SARS-CoV-2 during HBOT for idiopathic sudden sensorineural hearing loss. The other patients and the inside attendant who attended the sessions with her were regarded as contacts, tested for SARS-CoV-2, and quarantined until the test results were available. Ultimately, none of them tested positive. DISCUSSION: As HBOT in multiplace chambers entails a high risk of SARS-CoV-2 transmission, we strictly adapted our practice to consider that every patient could be a potential asymptomatic carrier. Therefore, the negative results of all contacts in this case and the fact that no confirmed cases of COVID-19 were reported suggests that these measures successfully prevented SARS-CoV-2 transmission in our HBOT clinic. SARS-CoV-2 transmission can be prevented if sufficient protective measures are taken.

Factors influencing the outcome of idiopathic sudden sensorineural hearing loss treated with hyperbaric oxygen therapy.

Idiopathic sudden sensorineural hearing loss (ISSNHL) is an otologic emergency with an incidence of about 5-20 per 100,000 of the population per year. There is no universally accepted standard protocol for the treatment of patients with ISSNHL. Hyperbaric oxygen therapy (HBOT), was first reported to improve the outcome following acute inner ear disorders during the late 1960s by both French and German authors. The increase in perilymph oxygenation produced by HBOT provides logical basis for the use of this treatment modality in ISSNHL. We reviewed the records of 97 cases that received HBOT for SSNHL to identify the factors that may affect the treatment outcomes. The effects of age, gender, affected ear, status of the contralateral ear, symptoms associated with hearing loss, presence of a cardiovascular disease, dyslipidemia, history of diabetes mellitus, seasonal factor, smoking, degree of hearing loss, audiogram type, medical treatments provided prior to HBOT, onset time, and number of HBOT sessions were evaluated. The mean hearing gain in all cases after the HBOT was 29.5 dB. The gains were statistically significant in the following cases: early onset of HBOT (p = 0.016), higher number of HBOT sessions (p < 0.01), steroid usage (p = 0.009), low frequency-ascending and total audiogram configuration (p < 0.01) and profound hearing loss (p = 0.011). The success rate was significantly lower in cases with high frequency-descending audiogram configuration (p < 0.001). The most important factor affected the prognosis favorably was found as steroid therapy. This retrospective study and our clinical experience suggest that HBOT has beneficial effects when administered in the early phase of the disease together with steroids. HBOT is a safe practice when used properly by an experienced hyperbaric team. In the treatment of ISSNHL, 20 sessions of HBOT at 2.5 ATA can be tolerated well besides some minor side effects. HBOT should be considered for the cases especially with total or profound hearing loss.

Paranasal sinus mucosal hypertrophy in experienced divers.

INTRODUCTION: Due to the increasing popularity in recreational diving long-term health consequences of this sport have aroused interest in the diving community. Although not as important as dysbaric osteonecrosis, ischemic brain lesions, or neurophysiological symptoms, paranasal sinus mucosal hypertrophy (PSMH) has also been discussed as being more prevalent among divers. In this study, we used magnetic resonance imaging (MRI) to compare asymptomatic divers with control subjects for PSMH. METHODS: We enrolled 79 male divers (34.0 +/- 5.7 yr) and 79 nondiving age- and sex-matched controls (33.8 +/- 6.1 yr). We used a questionnaire to elicit diving history. Divers with a history of sinus barotrauma, subjects with a history of chronic sinusitis or nasal allergies, and those with retention cysts, nasal polyps, or mastoiditis were excluded. T1-, T2-weighted axial and coronal images of the paranasal sinuses were taken with a 1.5-T MRI device. The threshold for PSMH was defined as mucosal thickness above 3 mm. RESULTS: MRI revealed PSMH in 33 (41.8%) divers and 18 (22.8%) controls. There were no significant differences between the groups with respect to age, smoking history, or alcohol consumption. PSMH identified in divers did not show an association with age or diving history. DISCUSSION: The higher rate of PSMH identified in divers suggests that diving may cause changes in the paranasal sinus mucosa.

The evaluation of in-chamber sound levels during hyperbaric oxygen applications: Results of 41 centres.

INTRODUCTION: Noise has physical and psychological effects on humans. Recommended exposure limits are exceeded in many hospital settings; however, information about sound levels in hyperbaric oxygen treatment chambers is lacking. This study measured in-chamber sound levels during treatments in Turkish hyperbaric centres. METHODS: Sound levels were measured using a sound level meter (decibel meter). All chambers were multiplace with similar dimensions and shapes. Eight measurements were performed in each of 41 chambers; three during compression, three during decompression, and two at treatment pressure, one during chamber ventilation (flushing) and one without ventilation. At each measurement a sound sample was collected for 25 seconds and A-weighted equivalent (LAeq) and C-weighted peak (LCpeak) levels were obtained. Recorded values were evaluated in relation to sound level limits in regulations. RESULTS: The highest sound level measured in the study was 100.4 dB(A) at treatment pressure while ventilation was underway and the lowest was 40.5 dB(A) at treatment pressure without ventilation. Most centres had sound levels between 70 dB and 85 dB throughout the treatment. Ventilation caused significant augmentation of noise. CONCLUSIONS: The chambers were generally safe in terms of noise exposure. Nevertheless, hyperbaric chambers can be very noisy environments so could pose a risk for noise-related health problems. Therefore, they should be equipped with appropriate noise control systems. Silencers are effective in reducing noise in chambers. Thus far, hyperbaric noise research has focused on chambers used for commercial diving. To our knowledge, this is the first study to investigate noise in hospital-based chambers during medical treatments.

Sponge divers of the Aegean and medical consequences of risky compressed-air dive profiles.

Historically, Turkey once had a substantial number of professional sponge divers, a population known for a relatively high incidence of diving-related conditions such as decompression sickness (DCS) and dysbaric osteonecrosis (DON). Sponge diving ended in the mid-1980s when nearly all of the sponges in the Aegean and Mediterranean Seas contracted a bacterial disease and the occupation became unprofitable. We reviewed the records of Turkish sponge divers for information on their level of knowledge, diving equipment, dive profiles, and occupational health problems. Information was collected by: 1) interviewing former sponge divers near Bodrum, where most of them had settled; 2) reviewing the relevant literature; and 3) examining the medical records of sponge divers who underwent recompression treatment. These divers used three types of surface-supplied equipment, including hard helmets, Fernez apparatus, and hookahs; the latter were preferred because they allowed divers the greatest freedom of movement while harvesting sponges underwater. These divers used profiles that we now know involved a high risk for DCS and DON. We were able to access the records of 58 divers who had received recompression treatment. All of the cases involved severe DCS and delays from dive to recompression that averaged 72 h. Complete resolution of symptoms occurred in only 11 cases (19%). Thus, we were able to document the several factors that contributed to the risks in this occupational group, including unsafe dive profiles, resistance to seeking treatment, long delays before recompression, and the fact that recompression treatment used air rather than oxygen.

Protective effect of hyperbaric oxygen treatment on rat intestinal mucosa after mesenteric ischaemia and reperfusion.

INTRODUCTION: Mesenteric ischaemia results from a lack of adequate blood flow to and oxygenation of the mesentery and intestines. The aim of the present study was to evaluate the effect of hyperbaric oxygen treatment (HBOT) on the healing process in intestinal mucosa of rats undergoing mesenteric ischaemia and reperfusion. METHODS: Thirty-two Wistar-Albino rats were divided into four groups of eight: 1) ischaemia/reperfusion (I/R); 2) sham operation; 3) I/R+HBOT started 6 hours after reperfusion; 4) I/R+HBOT started 12 hours after reperfusion. In the I/R groups, a vascular clamp was placed across the superior mesenteric artery to occlude arterial circulation for 60 minutes, followed by reperfusion. A dose of HBOT consisted of 100% oxygen breathing for 90 minutes at 2.5 atmospheres absolute pressure. Thirteen doses of HBOT were administered after ischaemia. The rats were sacrificed on the eighth day, and their intestinal tissues were harvested for histopathologic analysis. The tissue levels of catalase, malondialdehyde, and glutathione were determined. RESULTS: The histopathological scores (HSCORE) were consistent with macroscopic examinations. The scores were significantly higher (worse) in Group 1 compared to Group 2, Group 3, and Group 4 (for all comparisons, P < 0.05). Group 4's HSCORE was significantly higher than those of Group 2 and Group 3 (for both comparisons P < 0.05). Group 3's HSCOREs were only marginally higher than Group 2. Group 3 exhibited higher glutathione levels than Group 1 (P < 0.05). There were no significant differences across the groups with respect to malondialdehyde and catalase levels. CONCLUSION: A beneficial effect of HBOT was observed on oxidative stress and inflammation in acute mesenteric ischaemia-reperfusion.

Hyperbaric oxygen treatment of chronic refractory radiation proctitis: a randomized and controlled double-blind crossover trial with long-term follow-up.

PURPOSE: Cancer patients who undergo radiotherapy remain at life-long risk of radiation-induced injury to normal tissues. We conducted a randomized, controlled, double-blind crossover trial with long-term follow-up to evaluate the effectiveness of hyperbaric oxygen for refractory radiation proctitis. METHODS AND MATERIALS: Patients with refractory radiation proctitis were randomized to hyperbaric oxygen at 2.0 atmospheres absolute (Group 1) or air at 1.1 atmospheres absolute (Group 2). The sham patients were subsequently crossed to Group 1. All patients were re-evaluated by an investigator who was unaware of the treatment allocation at 3 and 6 months and Years 1-5. The primary outcome measures were the late effects normal tissue-subjective, objective, management, analytic (SOMA-LENT) score and standardized clinical assessment. The secondary outcome was the change in quality of life. RESULTS: Of 226 patients assessed, 150 were entered in the study and 120 were evaluable. After the initial allocation, the mean SOMA-LENT score improved in both groups. For Group 1, the mean was lower (p = 0.0150) and the amount of improvement nearly twice as great (5.00 vs. 2.61, p = 0.0019). Similarly, Group 1 had a greater portion of responders per clinical assessment than did Group 2 (88.9% vs. 62.5%, respectively; p = 0.0009). Significance improved when the data were analyzed from an intention to treat perspective (p = 0.0006). Group 1 had a better result in the quality of life bowel bother subscale. These differences were abolished after the crossover. CONCLUSION: Hyperbaric oxygen therapy significantly improved the healing responses in patients with refractory radiation proctitis, generating an absolute risk reduction of 32% (number needed to treat of 3) between the groups after the initial allocation. Other medical management requirements were discontinued, and advanced interventions were largely avoided. Enhanced bowel-specific quality of life resulted.

Are pulmonary bleb and bullae a contraindication for hyperbaric oxygen treatment?

BACKGROUND: Air cysts or blebs in the lungs may predispose pulmonary barotrauma (PBT) by causing air trapping when there is a change in environmental pressure. The changes in the environmental pressure are also seen during hyperbaric oxygen treatments (HBOT). AIM: The aim of this study was to determine how patients were evaluated for pulmonary blebs or bullae, and PBT prevalence in different HBOT centers. METHODS: HBOT centers were asked to participate in this study and a questionnaire was send via e-mail. A total of 98 centers responded to our questionnaire. RESULTS: Sixty-five HBOT centers (66.3%) reported that they applied HBOT to the patients with air cysts in their lungs. X-ray was the most widely used screening method for patients with a history of a lung disease. The prevalence of PBT in theses centers was calculated as 0.00045%. CONCLUSIONS: Our survey demonstrated that (1) a significant portion of the HBO centers accept patients with pulmonary bleb or bullae, (2) although insufficient, X-ray is the mostly used screening tool for patients with a history of pulmonary disease and (3) the prevalence of pulmonary barotrauma is very low in HBOT.

Dysbaric osteonecrosis screening in Turkish Navy divers.

INTRODUCTION: Dysbaric osteonecrosis (DON) is regarded as an occupational disease for caisson workers, commercial, and military divers. Magnetic resonance imaging (MRI) was suggested for the surveillance of military divers for DON. This study aimed to determine the prevalence of DON in Turkish Navy divers. METHODS: The shoulder, hip, and knee joints of 106 male divers were screened for DON with MRI. A questionnaire was used to obtain information about subjects' medical history and diving experience. RESULTS: The mean age of divers was 34.3 +/- 5.8 yr. The divers had spent an average of 12.1 +/- 6.1 yr at their occupation. The average of total hours of diving was 834 +/- 458 h. The maximum diving depth was 53.0 +/- 18.4 m (175 +/- 61 ft) and the average diving depth was 13.3 +/- 8.4 m (44 +/- 28 ft). MRI examinations of divers did not reveal bone lesions consistent with osteonecrosis. DISCUSSION: We concluded that the risk of DON is very low for military divers who strictly obey the decompression rules and who undergo periodic medical examination. The use of MRI for routine screening of military divers is not justified.