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At least 163 records · Page 9Linked to original sources

PubMed2004

Comparison of limited monitoring using a nasal-cannula flow signal to full polysomnography in sleep-disordered breathing.

STUDY OBJECTIVES: Evaluate the utility of overnight monitoring limited to nasal cannula airflow and oximetry in the diagnosis of obstructive sleep apnea-hypopnea syndrome (OSAHS). DESIGN: Prospective randomized study, blinded analysis. SETTING: Sleep disorder center, academic institution. PARTICIPANTS: 56 patients with suspected OSAHS, 10 normal volunteers. MEASUREMENTS AND RESULTS: In-laboratory full nocturnal polysomnography (NPSG) and unattended ambulatory study with monitoring of only airflow and oximetry performed in randomized order. Obstructive respiratory events were scored on the full NPSG while visualizing all signals and then rescored on the full NPSG and on the ambulatory study while visualizing only airflow and oximetry signals. Respiratory disturbance indexes (RDI) for the limited studies (RDIFlowNPSG and RDIFlowAmbulatory) were calculated as the sum of the apneas and hypopneas (defined using airflow amplitude and O2 desaturation) divided by the valid flow-signal time. The reference RDIFullNPSG was calculated from the sum of the apneas and hypopneas (defined using flow amplitude, O2 desaturation and electroencephalographic arousal) identified on the full NPSG divided by the total sleep time. RDIFullNPSG was greater than RDIFlowNPSG (bias = 5.6 events per hour) and RDIFlowAmbulatory (bias = 10.9 events per hour), but the differences were mainly in subjects with an RDI > 40 events per hour. The diagnostic sensitivity and specificity for the diagnosis of OSAHS using a cutoff of 18 events per hour were 96% and 93% using the flow signal from the NPSG and 88% and 92% using the flow signal from the ambulatory study performed on a separate night. CONCLUSIONS: In subjects with OSAHS, analysis of the flow signal from a nasal cannula can provide an RDI similar to that obtained in a full NPSG.

Adult↗

PubMed2006

Validation a portable monitoring device for sleep apnea diagnosis in a population based cohort using synchronized home polysomnography.

SUBJECT OBJECTIVE: To assess the accuracy of a portable monitoring device based on peripheral arterial tonometry to diagnose obstructive sleep apnea (OSA). To propose a new standard for limited-channel device validation using synchronized polysomnography (PSG) home recordings and a population-based cohort. DESIGN: Single-night, unattended PSG and Watch_PAT 100 (WP_100). SETTING: Home environment. PARTICIPANTS: Ninety-eight subjects (55 men; age, 60 +/- 7 year; body mass index, 28 +/- 4 kg/m2) consecutively recruited from the Skaraborg Hypertension and Diabetes Project. MEASUREMENTS AND RESULTS: The WP_100 records peripheral arterial tone, heart rate, oxygen saturation and actigraphy for automatic analysis of respiratory disturbance index (RDI), apnea-hypopnea index (AHI), oxygen desaturation index (ODI), and sleep-wake state. The accuracy of WP_100 in RDI, AHI, ODI, and sleep-wake detection was assessed by comparison with data from simultaneous PSG recordings. The mean PSG-AHI in this population was 25.5 +/- 22.9 events per hour. The WP_100 RDI, AHI, and ODI correlated closely (0.88, 0.90, and 0.92; p < .0001, respectively) with the corresponding indexes obtained by PSG. The areas under the curve for the receiver-operator characteristic curves for WP_100 AHI and RDI were 0.93 and 0.90 for the PSG-AHI and RDI thresholds 10 and 20 (p < .0001, respectively). The agreement of the sleep-wake assessment based on 30-second bins between the 2 systems was 82 +/- 7%. CONCLUSIONS: The WP_100 was reasonably accurate for unattended home diagnosis of OSA in a population sample not preselected for OSA symptoms. The current design, including simultaneous home PSG recordings in population-based cohorts, is proposed as a reasonable validation standard for assessment of simplified recording tools for OSA diagnosis.

Body Mass Index↗

PubMed1996

Polysomnography after adenotonsillectomy in mild pediatric obstructive sleep apnea.

OBJECTIVES: a) To determine the need for intensive monitoring on the first operative night of surgery in children undergoing adenotonsillectomy for mild obstructive sleep apnea; b) to examine the effect of narcotics on postoperative obstructive sleep apnea. DESIGN: Randomized, prospective study. SETTING: University hospital. PATIENTS: Children, ranging in age between 1 and 18 yrs, presented to the Pediatric Otolaryngology Clinic for adenotonsillectomy for mild obstructive sleep apnea defined as from one to 15 obstructive apnea events per hour on preoperative polysomnogram. INTERVENTIONS: Patients were assigned to receive either a narcotic- or a halothane-based anesthetic for adenotonsillectomy. A postoperative polysomnogram was performed in the pediatric intensive care unit on the first operative night. MEASUREMENTS AND MAIN RESULTS: Eighteen patients were recruited, 15 of whom met inclusion criteria: nine patients received a halothane-based anesthetic and six patients received a fentanyl-based anesthetic. When the data were analyzed by pooling both groups, the differences between pre- and postoperative sleep studies demonstrated a reduction in the number of obstructive events and less severe oxygen desaturations on the operative night. Total sleep time between the two sleep studies decreased from 371 +/- 13 to 304 +/- 14 mins. The number of obstructive apnea events/hr decreased as well. The lowest oxygen saturation measured during rapid eye movement sleep was 78 +/- 5% preoperatively and 92 +/- 1% postoperatively. CONCLUSIONS: Our data suggest that children without underlying medical conditions, neuromotor diseases, or carniofacial abnormalities, 1 to 18 yrs of age, who suffer from mild obstructive sleep apnea, have improvements documented by polysomnography on the night of surgery following adenotonsillectomy and do not necessarily need to be monitored intensively. These findings were not significantly affected by the choice of intraoperative anesthetic.

Adenoidectomy↗

PubMed1996

Characterization of postoperative edema following laser-assisted uvulopalatoplasty using MRI and polysomnography: implications for the outpatient treatment of obstructive sleep apnea syndrome.

Laser-assisted uvulopalatoplasty (LAUP) has been introduced as an alternative to uvuloplatopharyngoplasty for the treatment of snoring. Despite limited study, the use of this procedure has been expanded to include patients with obstructive sleep apnea syndrome. Although the potential cost-savings of performing sleep apnea surgery on an outpatient basis are self-evident, concern exists regarding the safety of this practice. In an effort to characterize the risk of performing LAUP on an outpatient basis, eight patients with mild or no sleep apnea were identified and intensively studied before and after the first stage of LAUP to cure snoring. Assessment included preoperative magnetic resonance imaging (MRI) scans, polysomnography, and videoendoscopy. Each of these diagnostic studies was then repeated between 48 and 72 hours after LAUP. Complete polysomnographic data were available for seven of the eight patients. The mean ( +/- SD) preoperative respiratory disturbance index (RDI) was 11.3 +/- 10.9, and the mean oxygen saturation nadir (LSAT) was 87.7 +/- 6.2% (n = 7). The mean airway cross-sectional area at the palate (by MRI) was 49.8 +/- 22.8 mm2 (n = 8). After LAUP, the mean RDI nearly doubled to 21.7 +/- 9.9 (P > .1). The apnea index increased fourfold from 3.3 +/- 3.5 to 14.8 +/- 10.9 (P < .03). The mean LSAT remained stable at 87.4 +/- 4.1% (P > .5). The cross-sectional area of the airway decreased to a mean of 47.9 +/- 22.4 mm2 (P > .5). These data suggest that LAUP may temporarily worsen obstructive sleep apnea. Although the clinical significance of this degree of worsening is uncertain, it would be prudent to consider perioperative use of nasal continuous positive airway pressure in patients with more than mild obstructive sleep apnea who undergo ambulatory LAUP.

Adult↗

PubMed2004

Magnesium treatment of primary alcohol-dependent patients during subacute withdrawal: an open pilot study with polysomnography.

BACKGROUND: Sleep electroencephalogram alterations and insomnia complaints persist after alcohol withdrawal in dependent patients and are considered strong predictors of relapse. Although disturbances of magnesium household due to alcohol consumption are well known, the relationship of magnesium metabolism and sleep disturbances has not been investigated in this patient group. We conducted an open pilot study to evaluate the effects of magnesium treatment on the sleep of primary alcohol-dependent patients during subacute withdrawal. METHODS: Patients were treated with 30 mmol magnesium daily over 4 weeks. Eleven of the 14 included patients were evaluated. Patients were free of any kind of psychotropic medication or other substances known to influence sleep. Polysomnographic recordings with monitoring of periodic leg movements in sleep (PLMS) were performed for two consecutive nights 2 weeks after acute withdrawal (baseline) and 4 weeks later at the end of the treatment period. After the baseline polysomnography, patients were investigated by the magnesium loading test to verify magnesium depletion. RESULTS: We found a significant decrease of sleep onset latency from 40.6 to 21.7 min (p = 0.03) and a significant improvement of subjective sleep quality, as assessed by the Pittsburgh Sleep Quality Index, from 8.1 to 5.8 (p = 0.05) during magnesium treatment. Changes in PLMS indices revealed two subgroups of patients: one with an increase of PLMS from 30.7 to 39.4 per hour of sleep (n = 4) and the other one with a decrease of PLMS from 8.9 to 2.1 per hour of sleep (p = 0.04). Patients with PLMS decreases seemed to have a more favorable prognosis: total sleep time, gamma-glutamyltransferase, carbohydrate-deficient transferrin, and Beck Depression Inventory scores improved significantly during treatment in this group. The magnesium loading test revealed a magnesium deficiency in only one patient, five patients showed normal retention values, and the remaining five patients had an increased magnesium excretion, indicating a possible continued renal magnesium loss during abstinence. CONCLUSIONS: The results of this study should be interpreted with caution, because no control group with placebo was investigated. Both subjective and, partly, objective parameters of sleep improved during the 4-week study period. Further research is needed to clarify the relationship of magnesium metabolism and sleep alterations.

Adult↗

PubMed2001

An arrhythmia detector and heart rate estimator for overnight polysomnography studies.

We present an algorithm for automatic on-line analysis of the electrocardiography (ECG) channel acquired during overnight polysomnography (PSG) studies. The system is independent of ECG morphology, requires no manual initialization, and operates automatically throughout the night. It highlights likely occurrences of arrhythmias and intervals of bad signal quality while outputting a continual estimate of heart rate. Algorithm performance is validated against standard ECG databases and PSG data. Results demonstrate a minimal false negative rate and a low false positive rate for arrhythmia detection, and robustness over a wide range of noise contamination.

Algorithms↗

PubMed2004

Symptomatic gastro-oesophageal reflux, arousals and sleep quality in patients undergoing polysomnography for possible obstructive sleep apnoea.

INTRODUCTION: Nocturnal acid reflux is common and could disturb sleep by causing arousals that fragment sleep. AIM: To determine the prevalence of gastro-oesophageal reflux symptoms and their association with arousals, stages of sleep and quality of life in patients undergoing evaluation for excessive daytime sleepiness and obstructive sleep apnoea. METHODS: Ninety-four consecutive patients with excessive daytime sleepiness were prospectively studied. Patients completed the gastrointestinal symptom rating scale, a validated symptom questionnaire for reflux disease and a disease-specific quality of life questionnaire, the sleep apnoea quality of life index and then underwent overnight polysomnography, which was read in a blinded manner. RESULTS: There were 40 males and 54 females with a mean age of 47 +/- 13 years. Reflux symptoms were present in 63 of the 94 (67%) patients. Patients with reflux symptoms had significantly more arousals from sleep 43 +/- 70/h than those without (20 +/- 24/h; P = 0.03). The sleep duration during the second stage of sleep was shorter (44 +/- 21%) for those with reflux symptoms than those without (52 +/- 12%; P = 0.03). Patients with reflux spent significantly shorter periods in stage II sleep (44 +/- 21%) than those without (52 +/- 12%; P = 0.03). The sleep-related quality of life score in patients with gastro-oesophageal reflux (3.1 +/- 1.1) was significantly lower than in patients without reflux (3.7 +/- 1.0; P = 0.02). Regression analysis demonstrated a significant inverse correlation between quality of life and reflux symptom score (P =0.002) and total spontaneous arousals (P = 0.04). CONCLUSIONS: Gastro-oesophageal reflux is common in patients with sleep disorders, is associated with increased arousal, decreased durations spent in the deeper stages of sleep and poorer sleep-related quality of life.

Arousal↗

PubMed1998

Prolonged polysomnography in a case with recurrent hypersomnia.

An 18-year-old male patient with recurrent hypersomnia (RH) was evaluated using prolonged polysomnography (PSG). During symptomatic period (SMP), the patient showed both 'dissociated stage REM' (DREM), REM sleep without muscle atonia and 'dissociated stage 1' (DSt-1), and stage 1 sleep with rapid eye movement. These stages were observed in the morning or following daytime record. They decreased during asymptomatic period (ASMP). It has been said that RH is caused by dysfunction of the hypothalamus and midbrain limbic system. The present result suggests also that RH involves dysfunction of the brain stem.

Adolescent↗

PubMed1998

Polysomnography and body temperature changes by phototherapy in a delayed sleep phase syndrome case.

We examined polysomnography (PSG) and body temperature in a patient with delayed sleep phase syndrome who responded to phototherapy. The patient was a 31-year-old woman whose condition had slightly improved by a vitamin B12 administration. Phototherapy was administered to her in combination with the vitamin B12 medication, and this combined treatment successfully advanced her delayed sleep phase. On PSG, the regimen showed shortened sleep latency, decreased total sleep time and stages 1 and 2 sleep, and increased slow wave sleep. Phototherapy also improved temporal distribution of delta half-waves (0.5-2.0 Hz, > or = 31 microV) as well as phase relationship between sleep and body temperature.

Adult↗

PubMed1996

Comparison of partially attended night time respiratory recordings and full polysomnography in patients with suspected sleep apnoea/hypopnoea syndrome.

BACKGROUND: Laboratory full polysomnography (PSG) is considered to be the gold standard for the diagnosis of the sleep apnoea/hypopnoea syndrome (SAHS), but it is expensive and time consuming. A study was undertaken to evaluate the diagnostic usefulness of a partially attended night time respiratory recording (NTRR) and a clinical questionnaire in patients with suspected SAHS in comparison with full PSG. METHODS: Seventy six patients (54 men) of mean (SD) age 51 (11.5) years with a body mass index of 31 (5.7) kg/m2 were studied at random on two different nights with full PSG at the sleep laboratory and with NTRR on a respiratory ward. NTRR records oximetry, airflow, chest and abdominal motion. All signals were continuously displayed on a computer screen throughout the night and respiratory events were scored automatically the following morning. All patients completed a clinical questionnaire. RESULTS: Mean values of the apnoea/hypopnoea index (AHI) using NTRR were lower than those obtained with full PSG (22.7 (2.4) versus 32.2 (3) events/hour) which was mainly due to underrecognition of hypopnoeas. Sensitivity and specificity of NTRR for the diagnosis of SAHS were 82% and 90%, respectively, taking as reference AHI > 10 on full PSG (AHI-PSG > 10). The mean (+/-2SD) difference in AHI between the two methods was 9.6 (range -5.4-24.6) (95% confidence interval 6.2 to 13). Symptoms of witnessed apnoeas, impotence, the overall clinical impression of a trained physician, and a neck size over 40 cm were significantly more prevalent in patients with AHI-PSG of > 10, but impotence was the only clinical feature significantly more prevalent in patients with false negative compared with true negative NTRR results that helped to distinguish patients with NTRR < 10 but AHI-PSG > 10. CONCLUSIONS: NTRR is a helpful and easy complementary diagnostic tool in clinical practice because it detects patients with moderate to severe SAHS reasonably well and therefore can be useful for confirming a diagnosis of SAHS and also for treatment decisions. It is suggested that patients with suspicion of SAHS should be initially studied by NTRR. When NTRR is negative, a full PSG should be performed if witnessed apnoeas, impotence, systemic hypertension, ischaemic heart disease, and a trained physician's clinical impression of SAHS are present.

Adult↗

PubMed1999

Nocturnal oximetry for the diagnosis of the sleep apnoea hypopnoea syndrome: a method to reduce the number of polysomnographies?

BACKGROUND: Polysomnography (PSG) is currently the "gold standard" for the diagnosis of the sleep apnoea hypopnoea syndrome (SAHS). Nocturnal oximetry (NO) has been used with contradictory results. A prospective study was performed to determine the accuracy of NO as a diagnostic tool and to evaluate the reduction in the number of PSGs if the diagnosis of SAHS had been established by this method. METHODS: Two hundred and seventy five patients with a clinical suspicion of SAHS were admitted to undergo, in the same night, full PSG and NO. Desaturation was defined as a fall in the haemoglobin saturation level (SaO(2)) to lower than 4% from the baseline level and an oxygen desaturation index per hour (ODI) was obtained in each patient with three cut off points: >/= 5 (ODI-5), >/= 10 (ODI-10), and >/= 15 (ODI-15). RESULTS: SAHS was diagnosed in 216 patients (194 men). After withdrawing patients with abnormal lung function (forced expiratory volume in one second (FEV(1)) lower than 80% predicted), sensitivity (SE), specificity (SP), positive and negative predictive values (PPV and NPV) of NO were: ODI-5 (80%, 89%, 97%, 48%); ODI-10 (71%, 93%, 97%, 42%); ODI-15 (63%, 96%, 99%, 38%). The accuracy for each ODI was 0.81, 0.75, and 0.70, respectively. If NO had been considered as a diagnostic tool and PSG had been performed only in patients with a negative NO (false negative and true negative) and those with a positive NO and abnormal pulmonary function tests, 135/275 (ODI-5), 156/275 (ODI-10), and 170/275 (ODI-15) PSGs would have been performed, a reduction of 140, 119, and 105, respectively. CONCLUSION: Nocturnal oximetry in patients with suspected SAHS and normal spirometric values permits the institution of therapeutic measures in most patients.

Female↗

PubMed2006

[Video-polysomnography in preterm infants with birth weight under 1,800 g].

INTRODUCTION: Neonatal video-polysomnography (VPSG) in preterm infants is indicated to rule out sleep-related respiratory disturbances before discharge from neonatal units and to study neonatal sleep patterns and associated pathologic conditions. OBJECTIVE: To study the presence of apnea, hypopnea, and periodic breathing in preterm infants with low birth weight (< 1,800 g) and to describe their cardio-respiratory variability, electroencephalogram (EEG) abnormalities, and brain maturity in connection with sleep stages. METHOD: We performed a cross-sectional, descriptive study through review of the clinical histories of preterm infants with a birth weight < 1,800 g who had undergone VPSG (2001-2003). The most common indication for VPSG was the presence of sleep apneas and oxygen desaturation. The data obtained were used for descriptive statistical analysis. RESULTS: Thirty-one infants were studied, with a mean gestational age of 27.8 weeks and a mean birth weight of 1,158 g. The most frequently associated condition was hyalin membrane disease (68 %). Cardiorespiratory impairment was detected in 65 %, altered sleep pattern in 6 %, immature EEG recording in 32 %, abnormal pattern in 13 %, and immature plus abnormal pattern in 3 %. Sixty-nine percent of the infants required home monitoring and 23 % needed oxygen at home. Four infants were readmitted on several occasions due to apnea. CONCLUSION: We wish to stress the importance of carrying out VPSG with suitable methodology in preterm infants with cardiorespiratory or neurological impairment in order to detect abnormalities on EEG and to assess brain maturity and sleep-related abnormal respiratory events.

Birth Weight↗

PubMed2000

Human sleep EEG under the influence of pulsed radio frequency electromagnetic fields. Results from polysomnographies using submaximal high power flux densities.

Former exploratory investigations of sleep alterations due to global system for mobile communications (GSM) signals have shown a hypnotic and REM-suppressive effect under field exposure. This effect was observed in a first study using a power flux density of 0.5 W/m(2), and the same trend occurred in a second study with a power flux density of 0.2 W/m(2). For the present study, we applied a submaximal power flux density of 50 W/m(2). To investigate putative effects of radio frequency electromagnetic fields (EMFs) of cellular GSM phones on human sleep EEG pattern, all-night polysomnographies of 20 healthy male subjects both with and without exposure to a circularly polarized EMF (900 MHz, pulsed with a frequency of 217 Hz, pulse duration 577 microseconds) were recorded. The results showed no significant effect of the field application either on conventional sleep parameters or on sleep EEG power spectra.

Adaptation, Physiological↗

PubMed1996

The effect of polysomnography on sleep position: possible implications on the diagnosis of positional obstructive sleep apnea.

This prospective study was designed to determine if physical constraint due to the polysomnography (PSG) apparatus affects PSG results by inducing subjects to sleep in the supine position. Twelve patients found to have positional obstructive sleep apnea (OSA) during standard PSG returned for two additional nights of study during which no PSG leads were attached. The time spent supine was 56% greater during the PSG night than the non-PSG nights, 195 +/- 88.6 min during the baseline PSG and 125 +/- 84.6 min during the non-PSG nights (p < 0.05). Therefore, PSG may overestimate the severity of OSA in some patients with positional OSA.

Adult↗

PubMed1997

History of clinical research on the sleep apnea syndrome. The early days of polysomnography.

This article gives a brief historical overview of the literature on the sleep apnea syndrome (SAS), including initial case reports of the Pickwickian syndrome and its treatment with tracheostomy. It also highlights the beginnings of early clinical neurophysiology and describes the breakthrough in the understanding of the pathophysiology of SAS by performing polysomnography.

History, 19th Century↗

PubMed2006

Validations of a portable home sleep study with twelve-lead polysomnography: comparisons and insights into a variable gold standard.

OBJECTIVES: Accurate and timely diagnosis for patients with obstructive sleep apnea (OSA) is imperative. Unfortunately, growing interest in this diagnosis has resulted in increased requests and waiting times for polysomnography (PSG), as well as a potential delay in diagnosis and treatment. This study evaluated the accuracy and viability of utilizing SNAP (SNAP Laboratories, LLC, Wheeling, Illinois), a portable home sleep test, as an alternative to traditional PSG in diagnosing OSA. METHODS: This prospective clinical trial included 59 patients evaluated at our institution's sleep laboratory. Concurrent PSG and SNAP testing was performed for 1 night on each patient. Independent, blinded readers at our institution and at an outside-accredited institution read the PSG data, and 2 independent, blinded readers interpreted the SNAP data at SNAP laboratories. The apnea-hypopnea index (AHI) was used to compare the 2 testing modalities. The correlation coefficient, receiver operating characteristic curve analysis, and the Bland-Altman curves, as well as sensitivity, specificity, inter-reader variability, positive predictive value, and negative predictive value, were used to compare SNAP and PSG. RESULTS: There is a definitive, statistically sound correlation between the AHIs determined from both PSG and SNAP. This relationship holds true for all measures of comparison, while displaying a concerning, weaker correlation between the different PSG interpretations. CONCLUSIONS: There is a convincing correlation between the study-determined AHIs of both PSG and SNAP. This finding supports SNAP as a suitable alternative to PSG in identifying OSA, while accentuating the inherent variation present in a PSG-derived AHI. This test expands the diagnostic and therapeutic prowess of the practicing otolaryngologist by offering an alternative OSA testing modality that is associated with not only less expense, decreased waiting time, and increased convenience, but also statistically proven accuracy.

Adult↗

PubMed2004

The yield of esophageal pH monitoring during polysomnography in infants with sleep-disordered breathing.

This study evaluates the yield of adding simultaneous esophageal pH monitoring to polysomnography (PSG) in 41 infants with unexplained sleep disordered breathing. The relationships of respiratory events to episodes of gastroesophageal reflux (GER) were analyzed. The major causes for referring the infants were cyanotic episodes (22%), apneas (20%), and choking events (15%). PSG was abnormal in 8/41 (20%). Abnormal pH studies were observed in 12/41 (29%) infants. In 4/12 (33%), respiratory events correlated with GER episodes. Adding simultaneous pH monitoring to PSG may identify associated conditions and thus focus treatment.

Esophagus↗

PubMed1996

Sleep apnea syndrome. Examination of pharyngeal obstruction with high-speed MR and polysomnography.

PURPOSE: We attempted to determine the usefulness of high-speed MR imaging for evaluating the severity of sleep apnea syndrome (SAS) by comparing findings of pharyngeal obstruction obtained with high-speed MR with those of all-night polysomnography (PSG). SUBJECTS AND METHODS: A total of 33 patients with SAS underwent turbo-FLASH MR examination, while awake and after i.v. injection of hydroxyzine hydrochloride. Serial images were examined by cinemode. Pharyngeal findings on MR were divided into single-site obstruction (SO) at the velopharynx, multiple-site obstruction (MO), and no obstruction (NO). PSG findings were analyzed to determine the predominant type of apnea, severity as evaluated by an apnea index (AI), and the lowest SaO2 value during sleep. RESULTS: Seventy-five percent of the central apnea group had SO, and 70% of the mixed apneas had MO, while only 15% of the obstructed apneas had MO. The percentage of patients with severe SAS (AI of 20% or higher) was 48% for the SO, and 70% for the MO. The lowest SaO2 value tended to be low in the mixed apnea in the case of PSG, and tended to be low in the MO at MR examination. CONCLUSION: Analysis of pharyngeal dynamics using high-speed MR may provide some useful information for evaluating the severity of SAS.

Aged↗