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Frequency doubling technology perimetry (FDT) soveltuvuus väestön glaukoomaseulontaan

Näytönastekatsaukset
Anja Tuulonen
27.8.2014

Näytön aste: C

FDT saattaa soveltua glaukooman seulontaan. Tutkimusten herkkyys ja tarkkuus vaihtelevat suuresti riippuen vertailutestistä. Tutkimusasetelmiin liittyi huomattava harhan riski.

Systemaattinen katsaus

A systematic review «Ervin AE, Boland MV, Myrowitz EH ym. Screening for...»1 was conducted through October 6, 2011 and existing databases were screend to identify relevant systematic reviews. The quantity, quality, and consistency of the body of available evidence was assesses for answering the question ‘What is the predictive value of screening tests for open-angle glaucoma?’

One systematic review (Burr et al., 2007) addressed the diagnostic test accuracy of candidate screening tests for the detection of OAG. Burr et al. (2007) conducted a diagnostic test accuracy review of candidate diagnostic and screening tests for OAG. Highly sensitive systematic electronic searches were undertaken by December 2005. The investigators included 40 studies totaling more than 48,000 participants 40 years of age and older and those at high risk for the development of OAG based on demographic characteristics or comorbidities. The focus was on studies of participants likely to be encountered in a routine screening setting. The primary reference standard was confirmation of OAG at followup examination. Also considered was diagnosis of OAG requiring treatment. No studies were at low risk of bias. A small subset of eight studies was judged to have higher quality.

After the Burr et al. 2007 systematic review, 4,960 studies were identified, of which 83 studies addressing the accuracy of screening tests were eligible. The sensitivity of standard automated perimetry (SAP) was higher than Goldmann tonometry, similar to the Heidelberg retina tomograph (HRT), and lower than disc photos or frequency doubling technology (FDT) visual field testing. The specificity of SAP was higher than disc photos and FDT, similar to HRT, and lower than Goldmann tonometry. Some comparisons of tests could not be performed due to variability in populations and reported thresholds. No other studies were identified.

68 % of studies were at high risk of spectrum bias (not representative of those who would receive the test in practice). 6 % had differential verification bias (different reference standards). The candidate test were interpreted without knowledge of reference standard in only 29 % of studies. 48 % of the studies did not include an explanation of withdrawals from the study, and 46 % of the studies reported the number of uninterpretable test results. Only 3 of 83 studies included a population-based sample.

FDT (C-20-1) Perimetry

Evidence From Burr et al., 2007

The pooled sensitivity and specificity results for the three studies that included FDT (C-20-1) perimetry and the common diagnostic criterion of one abnormal test point were high (92 and 94 %, respectively).

Evidence From Primary Studies

Four studies discussed the accuracy of FDT C-20 perimetry. One study enrolled 130 participants with ocular hypertension and 48 healthy volunteers. Using a cutoff of a cluster of at least four points with a sensitivity outside 95 % normal limits, or three points outside 98 % normal limits, or at least one point outside 99 % normal limits, investigators determined the sensitivity of FDT to be 31 % and its specificity 73 % among the subset of 32 participants with glaucomatous optic neuropathy (of the 130 with ocular hypertension). The investigators concluded that FDT might not be an ideal test for participants with early defects. Another study enrolled 35 participants with known OAG and 35 age- and sex-matched controls with no evidence of glaucoma. Investigators used FDT, noncontact tonometry, and a questionnaire individually and in all possible combinations to determine the accuracy of single and combination tests. FDT’s sensitivity was 58 % and its specificity was 99 %. Overall, FDT was determined to be the best among the candidate single and combination tests in the study, despite fair sensitivity for detecting OAG.

One study enrolled glaucoma patients who had never experienced perimetry prior to the study. The investigators reported that 21 (33 % percent) of the 64 participants with glaucoma were identified as having early disease, but data were not provided for this subgroup. Sensitivity and specificity were 86 and 74 %, respectively, for the presence of at least one abnormal location and 83 and 83 percent, respectively, for two or more abnormal locations, regardless of severity.

One study conducted population-based screening of 6,082 Latinos age 40 years and older as part of the Los Angeles Latino Eye Study (LALES) to determine the diagnostic accuracy of candidate screening tests performed alone or in combination.81 Participants completed Humphrey Visual Field testing in addition to FDT C-20-1, GAT, and central corneal thickness and cup-to-disc ratio measurements. Diagnostic test accuracy outcomes were assessed for the general population as well as high-risk subgroups, defined as persons who were 65 years and older, those with a family history of glaucoma, and persons with diabetes. Of the 6,082 participants screened, 4.7 percent (286) were diagnosed as having OAG. Based on three glaucoma diagnosis definitions (glaucomatous optic nerve appearance, glaucomatous visual field loss, glaucomatous optic nerve and visual field loss), the test parameters vertical cup-to-disc ratio ≥oss, glaucomatous optic nerve and visual field loss), the test parameters vertical cup-to-disc regardless of the definition of glaucoma (98 %). HVF mean deviation < 5 percent had the highest sensitivity (78 %) using the definition of optic nerve defects only, while the HVF glaucoma hemifield test had the highest sensitivity under the other two definitions (90 %) for glaucomatous visual field loss and 90 % for both field loss and optic nerve damage). Specific results for the FDT C-20-1 were as follows (sensitivity/specificity, definition of glaucoma): 59 % /79 % glaucomatous optic nerve appearance only; 68 %/80 %, glaucomatous visual field loss only; 67 % /79 %, both glaucomatous optic nerve appearance and visual field loss. The investigators reported similar results when high-risk subgroups were analyzed and concluded that “these results suggest that screening of high-risk groups based on these criteria may not improve over screening of the general population over age 40.”

FDT (C-20-5) Perimetry

Evidence From Burr et al., 2007

Five studies of FDT (C-20-5) with significant heterogeneity using the common cutoff point of one abnormal test point were included. The range of sensitivity was 7 to 100 %; the specificity range was 55 to 89 %.

FDT 24-2 Perimetry

Evidence From Primary Studies

Five studies examined the diagnostic accuracy of FDT 24-2 threshold tests using the Humphrey Matrix Perimeter. All studies included participants with known glaucoma and healthy volunteers, and we judged these studies to be at high risk of spectrum bias. The range of sample size was 25 to 174 glaucomatous eyes and 15 to 164 healthy eyes. Sensitivities and specificities were reported for the parameters mean deviation, pattern standard deviation, and glaucoma hemifield test outside of normal limits. There was appreciable heterogeneity in the estimates of sensitivity at 80 %, 90 %, and 95 % specificity that may be attributed to a number of factors, including different patient populations and variations in cutoff points. The sensitivity was 55 % for the mean deviation and 94 % at 80 % fixed specificity. Two studes reported 39 and 87 % at 90 % fixed specificity, and 32 and 82 % at fixed 95 % specificity, respectively. Sensitivity and specificity for pattern standard of deviation (PSD) and glaucoma hemifield test are reported with their cutoff points in the evidence tables in Appendix C of the full report.

Two studies reported the AUC for the mean deviation parameter (0.69 for both studies with p < 0.04 and 95 % CI, 0.564 to 0.815, respectively). The AUCs for PSD were 0.66 (p = 0.09) and 0.733 (95 % CI, 0.618 to 0.848).

FDT 30-2 Perimetry

Evidence From Primary Studies

Two studies discussed the detection of early glaucoma using the FDT 30-2 threshold test with the Humphrey Matrix Perimeter. Both studies enrolled OAG participants with early visual field loss and healthy controls. The mean deviation and PSD were judged to be good parameters for distinguishing between eyes with early disease and eyes with no known defects. The mean deviations were 0.795 and 0.750 and the PSDs were 0.808 and 0.934, respectively. Both study groups, however, determined that the best parameter for distinguishing eyes with early glaucoma from healthy eyes was the number of points that have p less than 5 % in the pattern deviation plot, with an AUC of 0.985 (95 % CI, 0.943 to 0.998) and 0.990 (p < 0.001).

FDT N-30 Perimetry

Evidence From Primary Studies

Four studies examined the accuracy of the FDT N-30 threshold test. One study focused on the detection of early glaucoma among a sample of 75 participants with OAG, 87 with ocular hypertension, 67 with glaucomatous optic neuropathy, and 90 healthy volunteers. At the best cutoff of less than -0.78, the sensitivity of the mean deviation parameter was 61 % and the specificity was 74 % for distinguishing early OAG from healthy eyes. At the best cutoff of greater than 3.89, the sensitivity of the PSD was 76 % and thespecificity was 88 %. Another study focused on the detection of early disease among a sample of 52 participants with early OAG and 53 healthy volunteers. The sensitivity of mean deviation for distinguishing early OAG from healthy eyes at the best cutoff (less than -1.12) was 67 % and the specificity was 74 %. At the best cutoff of greater than 3.97,the sensitivity of the parameter PSD was 96 % and the specificity was 85 %.

Kirjallisuutta

  1. Ervin AE, Boland MV, Myrowitz EH ym. Screening for Glaucoma: Comparative Effectiveness. Comparative Effectiveness Review Number 59 AHRQ Publication No. 12-EHC037-EF, April 2012; http://www.effectivehealthcare.ahrq.gov/ehc/products/182/1026/CER59_Glaucoma-Screening_Final-Report_20120524.pdf