Diagnostic accuracy in retinoblastoma

This study was done to ascertain the accuracy of diagnosis and possible risk of misdiagnosis in suspected retinoblastoma cases by different pre-operative diagnostic procedures like fundoscopy, ultrasonography, computerised tomography, and aqueous cytology study. Twenty-four eyes excised with diagnosis of suspected retinoblastoma were included in the study. Final diagnosis was reached by histopathological examination of excised eyes and compared with pre-operative diagnosis by different diagnostic procedures and accuracy of each procedure was calculated. Twenty-two cases were finally diagnosed as retinoblastoma and 2 cases (8.33%) as other than retinoblastoma. Computerised tomography and aqueous humour cytology were two most specific (100%) tests. Computerised tomography was the most sensitive (95.4%) test. Aqueous cytology was poorly sensitive (9.09%). Both ultrasonography and fundoscopy demonstrated sensitivity over 90% but with low specificity (50%). When test results of fundoscopy and ultrasonography were combined, specificity of this combination was 100% and sensitivity was 95.4%, which match exactly the values of computerised tomography. Combination of fundoscopy and ultrasonography has accuracy as high as that of computerised tomography. In patients with clear media this combination can be used as an effective alternative to computerised tomography to reach a diagnosis with comparable accuracy.