title: Sensitivity and specificity of diagnostic ultrasound in the diagnosis of phrenic neuropathy.
abstract: OBJECTIVE
  To determine the sensitivity and specificity of B-mode ultrasound in the diagnosis of neuromuscular diaphragmatic dysfunction, including phrenic neuropathy.
  
  
  METHODS
  A prospective study of patients with dyspnea referred to the EMG laboratory over a 2-year time frame for evaluation of neuromuscular respiratory failure who were recruited consecutively and examined with ultrasound for possible diaphragm dysfunction. Sonographic outcome measures were absolute thickness of the diaphragm and degree of increased thickness with maximal inspiration. The comparison standard for diagnosis of diaphragm dysfunction was the final clinical diagnosis of clinicians blinded to the diaphragm ultrasound results, but taking into account other diagnostic workup, including chest radiographs, fluoroscopy, phrenic nerve conduction studies, diaphragm EMG, and/or pulmonary function tests.
  
  
  RESULTS
  Of 82 patients recruited over a 2-year period, 66 were enrolled in the study. Sixteen patients were excluded because of inconclusive or insufficient reference testing. One hemidiaphragm could not be adequately visualized; therefore, hemidiaphragm assessment was conducted in a total of 131 hemidiaphragms in 66 patients. Of the 82 abnormal hemidiaphragms, 76 had abnormal sonographic findings (atrophy or decreased contractility). Of the 49 normal hemidiaphragms, none had a false-positive ultrasound. Diaphragmatic ultrasound was 93% sensitive and 100% specific for the diagnosis of neuromuscular diaphragmatic dysfunction.
  
  
  CONCLUSIONS
  B-mode ultrasound imaging of the diaphragm is a highly sensitive and specific tool for diagnosis of neuromuscular diaphragm dysfunction.
  
  
  METHODS
  This study provides Class II evidence that diaphragmatic ultrasound performed by well-trained individuals accurately identifies patients with neuromuscular diaphragmatic respiratory failure (sensitivity 93%; specificity 100%).
authors.affiliation: From the Departments of Physical Medicine and Rehabilitation (A.J.B., J.A.S., S.G.) and Neurology (A.J.B., J.A.S., J.C.W., E.J.S.), and Divisions of Pain Medicine (Dr. Watson) and Pulmonary and Critical Care Medicine (H.S.), Mayo Clinic, Rochester, MN. C.J.H. is a student, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN. boon.andrea@mayo.edu.
authors.forename: Andrea J
authors.initials: AJ
authors.lastname: Boon
authors.affiliation: From the Departments of Physical Medicine and Rehabilitation (A.J.B., J.A.S., S.G.) and Neurology (A.J.B., J.A.S., J.C.W., E.J.S.), and Divisions of Pain Medicine (Dr. Watson) and Pulmonary and Critical Care Medicine (H.S.), Mayo Clinic, Rochester, MN. C.J.H. is a student, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Sekiguchi
authors.affiliation: From the Departments of Physical Medicine and Rehabilitation (A.J.B., J.A.S., S.G.) and Neurology (A.J.B., J.A.S., J.C.W., E.J.S.), and Divisions of Pain Medicine (Dr. Watson) and Pulmonary and Critical Care Medicine (H.S.), Mayo Clinic, Rochester, MN. C.J.H. is a student, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN.
authors.forename: Caitlin J
authors.initials: CJ
authors.lastname: Harper
authors.affiliation: From the Departments of Physical Medicine and Rehabilitation (A.J.B., J.A.S., S.G.) and Neurology (A.J.B., J.A.S., J.C.W., E.J.S.), and Divisions of Pain Medicine (Dr. Watson) and Pulmonary and Critical Care Medicine (H.S.), Mayo Clinic, Rochester, MN. C.J.H. is a student, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Strommen
authors.affiliation: From the Departments of Physical Medicine and Rehabilitation (A.J.B., J.A.S., S.G.) and Neurology (A.J.B., J.A.S., J.C.W., E.J.S.), and Divisions of Pain Medicine (Dr. Watson) and Pulmonary and Critical Care Medicine (H.S.), Mayo Clinic, Rochester, MN. C.J.H. is a student, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN.
authors.forename: Leili S
authors.initials: LS
authors.lastname: Ghahfarokhi
authors.affiliation: From the Departments of Physical Medicine and Rehabilitation (A.J.B., J.A.S., S.G.) and Neurology (A.J.B., J.A.S., J.C.W., E.J.S.), and Divisions of Pain Medicine (Dr. Watson) and Pulmonary and Critical Care Medicine (H.S.), Mayo Clinic, Rochester, MN. C.J.H. is a student, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN.
authors.forename: James C
authors.initials: JC
authors.lastname: Watson
authors.affiliation: From the Departments of Physical Medicine and Rehabilitation (A.J.B., J.A.S., S.G.) and Neurology (A.J.B., J.A.S., J.C.W., E.J.S.), and Divisions of Pain Medicine (Dr. Watson) and Pulmonary and Critical Care Medicine (H.S.), Mayo Clinic, Rochester, MN. C.J.H. is a student, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Sorenson
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003964:Diaphragm / Q000000981:diagnostic imaging* / Q000503:physiopathology; D004417:Dyspnea / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D005189:False Positive Reactions; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010523:Peripheral Nervous System Diseases / Q000150:complications / Q000175:diagnosis* / Q000000981:diagnostic imaging* / Q000503:physiopathology; D010791:Phrenic Nerve / Q000000981:diagnostic imaging* / Q000503:physiopathology; D011446:Prospective Studies; D011859:Radiography; D012131:Respiratory Insufficiency / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000503:physiopathology; D012680:Sensitivity and Specificity; D014463:Ultrasonography