21/xsl/MobileMenu.xsltmobileNave880e1541/WorkArea//http://rsna.org/TwoColumnWireframe.aspx?pageid=2794&id=9295&ekfxmen_noscript=1&ekfxmensel=falsefalsetruetruetruefalsefalse10-18.0.0.0730truefalse
  •  
     
  • News App
  • To:
    From:
    Subject:
    Comment:
    Link:
      
  • Imaging Advancements Aid in Sleep Apnea Therapy, Detection

    June 01, 2013

    Advancements in dynamic CT and MR imaging technology are proving successful in diagnosing and treating patients with obstructive sleep apnea syndrome.

    Cine MR imaging provides the 3D isotropic resolution necessary to obtain very high spatial and temporal imaging of the entire upper airway and surrounding soft tissue, allowing for high-quality computerized reconstruction of the entire airway, according to researcher Mark Wagshul, Ph.D., who introduced the technique at RSNA 2011 and presented his most recent findings at RSNA 2012.

    “Cine MR imaging offers complete coverage of the entire upper airway with isotropic resolution, allowing image reformatting in any plane you desire,” said Dr. Wagshul, an associate professor at the Gruss Magnetic Resonance Research Center at the Albert Einstein College of Medicine, New York. “Also, the entire airway is collected under identical respiratory conditions. Finally, the technique provides retrospective gating which can be used to limit imaging to specific physiological conditions such as normal tidal breathing versus an apneic event.”

    OSAS affects 3 to 7 percent of the adult population, more than half of whom are overweight. Other risk factors for OSAS include a narrowed airway, family history, being older (OSAS occurs significantly more in those over 60), and use of alcohol, sedatives or tranquilizers. Untreated, OSAS can lead to heart attacks, strokes, impotence, irregular heartbeat, high blood pressure and heart disease and can cause daytime sleepiness resulting in accidents, work-related problems and interpersonal problems, among other issues.

    OSAS is also present in 2 to 4 percent of children, but the incidence increases by as much as 50 percent for obese children. “It’s becoming especially important given the increasing prevalence of obesity in children in the U.S.,” Dr. Wagshul said. “Obstructive sleep apnea syndrome is associated with fatigue and poor school performance.”

    Very detailed computational models of the airway and surrounding tissues can be created using the dynamic information available, providing the physicians with information about flow, pressure and airway motion unique to OSAS patients. The technology will also allow simulation of surgical procedures, allowing physicians to see the impact a procedure such as tonsil removal would have on airway flow.

    “This is critical for allowing surgeons to practice a more focused and physiology-based approach to resection with better outcomes,” Dr. Wagshul said.

    In their latest study, Dr. Wagshul and colleagues examined 20 females between 13 and 18 years old who being were evaluated for polycystic ovary syndrome (PCOS), a disorder affecting 5 to 10 percent of girls and women of reproductive age which leads to obesity and has been associated with OSAS. OSAS is 30 times more prevalent in females with PCOS than in the general population, Dr. Wagshul said.

    Researchers detected three patients with severe OSAS and four with mild OSAS and imaged the computerized models of the girls’ upper airways while they were awake. Images of the severe cases revealed the upper portions of the airway constricting during one part of the breathing cycle and at the same time expanding lower down in the airway. Cases of mild OSAS revealed more synchronous motion of the entire airway.

    “In the more severe patients, we can see an abrupt change in the timing of the airway motion going from the velopharynx into the oropharynx, precisely at the site of restriction in the severe cases,” Dr. Wagshul said. “Other studies in the group have shown that such motion may be due to activation of the muscles surrounding the airway, likely compensation for change in airflow due to the airway constriction.

    Dr. Wagshul continues to examine data from the study.

    Multislice CT Aids in OSAS Detection, Treatment

    Although the standard diagnostic test for OSAS is a polysomnogram, Brazilian researchers contend that multislice craniofacial CT imaging can aid ENT physicians and maxillofacial surgeons in detecting soft tissue and skeletal factors that can alter the mechanical properties of the upper airway and its tendency to collapse during sleep.

    A number of anatomical features can predispose a person to OSAS, many of them potentially treated with surgery, said Natalia Sabaneeff, M.D., a radiologist at Centro De Diagnostico Por Imagem in Rio de Janeiro who presented, “3D CT Cephalometric Analysis and Sleep Apnea: How Can We Help the Otorhinolaryngologist?” at RSNA 2012.

    “Retrognathia and maxillary deficiency, low positioned hyoid bone, enlarged soft palate and tongue and tonsillar hypertrophy are some of the conditions that can increase the incidence of sleep disorders,” Dr. Sabaneeff said. “MDCT and cephalometric analysis can help diagnose anatomical causes of sleep apnea, affecting the management of such patients.”

    Cephalometric analysis—the study of dental and skeletal relationships in the head—can be performed by radiograph, CT and even MR imaging, Dr. Sabaneeff said. “However, MDCT is the best single imaging method to study patients with sleep apnea,” she added. “It provides great spatial resolution in a short acquisition time and allows tridimensional reconstructions for studying skeletal abnormalities and soft tissue/airway analysis.”

    MDCT can further aid ENT physicians by providing information to determine a course of treatment potentially more helpful than continuous positive airway pressure (CPAP), the standard OSAS treatment. This is especially true when patients using oral appliances such as tongue-retaining devices present with anatomic factors that could result in OSAS. In addition, MDCT can help physicians decide whether to perform surgical treatments such as nasal surgery, uvulopalatopharyngoplasty, genioglossus advancement, adenotonsillectomy and maxillomandibular advancement.

    “In order to decide the best treatment option, it is essential to perform cephalometric studies in those patients,” Dr. Sabaneeff said. q

    Web Extras

    Mark Wagshul, Ph.D. video

    VideoHear Mark Wagshul, Ph.D., an associate professor at the Gruss Magnetic Resonance Research Center at the Albert Einstein College of Medicine, New York, discuss:

    1. Obstructive sleep apnea syndrome and its impact on patients, here.
    2. Advancements offered by retrospective gating in enabling 3D, high-resolution, dynamic imaging of the upper airway, here.
    3. The method and results of his RSNA 2012 research, here.
    4. The impact of his research on clinical practice, here.

    To access an abstract of the research, “Novel Retrospective, Respiratory-Gating Method Enables 3D, High Resolution, Dynamic Imaging of the Upper Airway During Tidal Breathing,” by Dr. Wagshul and colleagues, go to www.ncbi.nlm.nih.gov/pubmed/23401041.

    Mark Wagshul, Ph.D.
    Wagshul
    Sleep Apnea CT
    Multislice craniofacial CT imaging can aid otorhinolaryngologists and maxillofacial surgeons in detecting soft tissue and skeletal factors that can alter the mechanical properties of the upper airway and its tendency to collapse during sleep, according to researchers. Images courtesy of Natalia Sabaneeff, M.D.
  • comments powered by Disqus

We appreciate your comments and suggestions in our effort to improve your RSNA web experience.

Name (required)

 

Email Address (required)

 

Comments (required)

 

 

 

 

Discounted Dues: Eligible North American Countries 
Belize
Costa Rica
Dominican Republic
El Salvador
Grenada
Guatamala
Haiti
Honduras
Jamaica
Netherlands Antilles
Nicaragua
Panama
St.Lucia
St. Vincent & Grenadines
Country    Country    Country 
Afghanistan   Grenada   Pakistan
Albania   Guatemala   Papua New Guinea
Algeria   Guinea   Paraguay
Angola   Guinea-Bissau   Peru
Armenia   Guyana   Phillippines
Azerbaijan   Haiti   Rwanda
Bangladesh   Honduras   Samoa
Belarus   India   Sao Tome & Principe
Belize   Indonesia   Senegal
Benin   Iran   Serbia
Bhutan   Iraq   Sierra Leone
Bolivia   Jordan   Solomon Islands
Bosnia & Herzegovina   Jamaica   Somalia
Botswana   Kenya   South Africa
Bulgaria   Kiribati   South Sudan
Burkina Faso   Korea, Dem Rep (North)   Sri Lanka
Burundi   Kosovo   St Lucia
Cambodia   Kyrgyzstan   St Vincent & Grenadines
Cameroon   Laos\Lao PDR   Sudan
Cape Verde   Lesotho   Swaziland
Central African Republic   Liberia   Syria
Chad   Macedonia   Tajikistan
China   Madagascar   Tanzania
Colombia   Malawi   Thailand
Comoros   Maldives   Timor-Leste
Congo, Dem. Rep.   Mali   Togo
Congo, Republic of   Marshall Islands   Tonga
Cote d'Ivoire   Mauritania   Tunisia
Djibouti   Micronesia, Fed. Sts.   Turkmenistan
Dominica   Moldova   Tuvalu
Domicican Republic   Mongolia   Uganda
Ecuador   Montenegro   Ukraine
Egypt   Morocco   Uzbekistan
El Salvador   Mozambique   Vanuatu
Eritrea   Myanmar   Vietnam
Ethiopia   Namibia   West Bank & Gaza
Fiji   Nepal   Yemen
Gambia, The   Nicaragua   Zambia
Georgia   Niger   Zimbabwe
Ghana   Nigeria    

Legacy Collection 2
Radiology Logo
RadioGraphics Logo 
Tier 1

  • Bed count: 1-400
  • Associate College: Community, Technical, Further Education (UK), Tribal College
  • Community Public Library (small scale): general reference public library, museum, non-profit administration office

Tier 2

  • Bed count: 401-750
  • Baccalaureate College or University: Bachelor's is the highest degree offered
  • Master's College or University: Master's is the highest degree offered
  • Special Focus Institution: theological seminaries, Bible colleges, engineering, technological, business, management, art, music, design, law

Tier 3

  • Bedcount: 751-1,000
  • Research University: high or very high research activity without affiliated medical school
  • Health Profession School: non-medical, but health focused

Tier 4

  • Bed count: 1,001 +
  • Medical School: research universities with medical school, including medical centers

Tier 5

  • Consortia: academic, medical libraries, affiliated hospitals, regional libraries and other networks
  • Corporate
  • Government Agency and Ministry
  • Hospital System
  • Private Practice
  • Research Institute: government and non-government health research
  • State or National Public Library
  • Professional Society: trade unions, industry trade association, lobbying organization