HSC Section 8_April 2017

CT IMAGING IN OTOSCLEROSIS

TABLE 3.

Study characteristics

CT Slice Thickness

Diagnostic Criteria CT

Diagnostic Criteria Surgery and/or Histopathology

Study (Year)

Study Population

Type of CT

Shin (2001a) (18)

Conductive hearing loss with a normal tympanic membrane

HRCT

1 mm Otospongiotic foci

Intraoperatively established presence of fixation or macropscopic otosclerotic foci, and absence of minor malformations Intraoperatively established in at least one ear Intraoperatively established, not further specified Intraoperatively established, not further specified Intraoperatively established macroscopic otosclerotic foci Pseudovascular spaces filled with osteoclasts (active otosclerosis) or obliterated vascular spaces and resorption of lacunae with

surrounding the otic capsule and/or footplate thickening

Kiyomizu (2004) (6)

Otosclerosis surgically confirmed in at least one ear

NA

1mm Focus of

demineralization or thick anterior and posterior calcified plaques

Trojanowska (2007) (19) Indication for middle ear surgery

Multislice CT 0.6 mm Hypodense foci

around otic capsule

Tringali (2007) (20)

Intraoperatively confirmed otosclerosis Conductive hearing loss with a normal tympanic membrane and absent or biphasic stapedial reflex in at least one ear Intraoperatively confirmed otosclerosis and stapes completely removed for histopathology

Helical CT 0.6 mm Focus of

demineralization

Marx (2011) (16),

HRCT

0.6mm to 1 mm

Hypodense foci

Lagleyre (2009) (17)

around otic capsule

Karosi (2012) (3)

HRCT

0.6 mm Hypodense foci

around otic capsule and/or footplate thickening

decreased numbers of osteoclasts (inactive otosclerosis) histopathologically

Liktor (2014) (2)

Intraoperatively confirmed otosclerosis and stapes completely removed for histopathology

Cone beam CT 0.4 mm Hypodense foci around otic capsule

Pseudovascular spaces filled with osteoclasts (active otosclerosis) or obliterated vascular spaces and resorption of lacunae with decreased

numbers of osteoclasts (inactive otosclerosis) histopathologically

HRCT indicates high-resolution computed tomography; NA, not available.

of these studies patients with a clinical suspicion of otosclerosis were included (16–18). In one study patients with surgically confirmed otosclerosis were included. Since the outcome measure in this study was histopa- thology instead of middle ear surgery, the prevalence of (histopathologically confirmed) otosclerosis was not

Prevalence of Otosclerosis In three studies, the prevalence of otosclerosis was 100% and as a result only sensitivities could be calcu- lated for these studies (2,6,20). Prevalences were high in the studies performed by Marx et al./Lagleyre et al. (16,17), Shin et al. (18), and Karosi et al. (3). In two

TABLE 4.

Results

Positive Post-test Probability a

Negative Post-test Probability a

Prevalence a

Sensitivity a

Specificity a

Study (Year)

Reference Test

Shin (2001a) (18) Kiyomizu (2004) (6)

Middle ear surgery 92 (89–94) Middle ear surgery 100 (95–100)

91 (88–94) 61 (50–71) 75 (50–90) 82 (74–88) 95 (91–97)

100 (89–100)

NA NA

51 (NA)

NA

NA

Trojanowska (2007) (19) Tringali (2007) (20) Marx (2011) (16), Lagleyre (2009) (17) Karosi (2012) (3)

Middle ear surgery

9 (6–14)

75 (68–81)

23 (13–36)

3 (2–6)

Middle ear surgery 100 (96–100) Middle ear surgery 97 (94–99)

NA

NA

NA

83 (42–98)

99 (96–100)

67 (22–93)

Histopathology Histopathology

74 (61–83)

60 (45–73) 66 (48–80)

100 (76–100)

NA NA

53 (NA)

Liktor (2014) (2)

100 (87–100)

NA

NA

NA indicates not available. a % (95% confidence interval).

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