Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures
OBJECTIVE: To evaluate the ability of orbital apex crowding volume measurements calculated with multidetector-computed tomography to detect dysthyroid optic neuropathy. METHODS: Ninety-three patients with Graves' orbitopathy were studied prospectively. All of the patients underwent a complete n...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier España
2012-08-01
|
| Series: | Clinics |
| Subjects: | |
| Online Access: | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1807-59322012000800006 |
| _version_ | 1818247518054514688 |
|---|---|
| author | Allan C. Pieroni Gonçalves Lucas Nunes Silva Eloísa M. M. S. Gebrim Suzana Matayoshi Mário Luiz Ribeiro Monteiro |
| author_facet | Allan C. Pieroni Gonçalves Lucas Nunes Silva Eloísa M. M. S. Gebrim Suzana Matayoshi Mário Luiz Ribeiro Monteiro |
| author_sort | Allan C. Pieroni Gonçalves |
| collection | DOAJ |
| description | OBJECTIVE: To evaluate the ability of orbital apex crowding volume measurements calculated with multidetector-computed tomography to detect dysthyroid optic neuropathy. METHODS: Ninety-three patients with Graves' orbitopathy were studied prospectively. All of the patients underwent a complete neuro-ophthalmic examination and computed tomography scanning. Volumetric measurements were calculated from axial and coronal contiguous sections using a dedicated workstation. Orbital fat and muscle volume were estimated on the basis of their attenuation values (in Hounsfield units) using measurements from the anterior orbital rim to the optic foramen. Two indexes of orbital muscle crowding were calculated: i) the volumetric crowding index, which is the ratio between soft tissue (mainly extraocular muscles) and orbital fat volume and is based on axial scans of the entire orbit; and ii) the volumetric orbital apex crowding index, which is the ratio between the extraocular muscles and orbital fat volume and is based on coronal scans of the orbital apex. Two groups of orbits (with and without dysthyroid optic neuropathy) were compared. RESULTS: One hundred and two orbits of 61 patients with Graves' orbitopathy met the inclusion criteria and were analyzed. Forty-one orbits were diagnosed with Graves' orbitopathy, and 61 orbits did not have optic neuropathy. The two groups of orbits differed significantly with regard to both of the volumetric indexes (p<0.001). Although both indexes had good discrimination ability, the volumetric orbital apex crowding index yielded the best results with 92% sensitivity, 86% specificity, 81%/94% positive/negative predictive value and 88% accuracy at a cutoff of 4.14. CONCLUSION: This study found that the orbital volumetric crowding index was a more effective predictor of dysthyroid optic neuropathy than previously described computed tomography indexes were. |
| first_indexed | 2024-12-12T15:05:58Z |
| format | Article |
| id | doaj.art-e7aa6d4fb8444bd88fea09d39569f34e |
| institution | Directory Open Access Journal |
| issn | 1807-5932 1980-5322 |
| language | English |
| last_indexed | 2024-12-12T15:05:58Z |
| publishDate | 2012-08-01 |
| publisher | Elsevier España |
| record_format | Article |
| series | Clinics |
| spelling | doaj.art-e7aa6d4fb8444bd88fea09d39569f34e2022-12-22T00:20:44ZengElsevier EspañaClinics1807-59321980-53222012-08-0167889189610.6061/clinics/2012(08)06Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structuresAllan C. Pieroni GonçalvesLucas Nunes SilvaEloísa M. M. S. GebrimSuzana MatayoshiMário Luiz Ribeiro MonteiroOBJECTIVE: To evaluate the ability of orbital apex crowding volume measurements calculated with multidetector-computed tomography to detect dysthyroid optic neuropathy. METHODS: Ninety-three patients with Graves' orbitopathy were studied prospectively. All of the patients underwent a complete neuro-ophthalmic examination and computed tomography scanning. Volumetric measurements were calculated from axial and coronal contiguous sections using a dedicated workstation. Orbital fat and muscle volume were estimated on the basis of their attenuation values (in Hounsfield units) using measurements from the anterior orbital rim to the optic foramen. Two indexes of orbital muscle crowding were calculated: i) the volumetric crowding index, which is the ratio between soft tissue (mainly extraocular muscles) and orbital fat volume and is based on axial scans of the entire orbit; and ii) the volumetric orbital apex crowding index, which is the ratio between the extraocular muscles and orbital fat volume and is based on coronal scans of the orbital apex. Two groups of orbits (with and without dysthyroid optic neuropathy) were compared. RESULTS: One hundred and two orbits of 61 patients with Graves' orbitopathy met the inclusion criteria and were analyzed. Forty-one orbits were diagnosed with Graves' orbitopathy, and 61 orbits did not have optic neuropathy. The two groups of orbits differed significantly with regard to both of the volumetric indexes (p<0.001). Although both indexes had good discrimination ability, the volumetric orbital apex crowding index yielded the best results with 92% sensitivity, 86% specificity, 81%/94% positive/negative predictive value and 88% accuracy at a cutoff of 4.14. CONCLUSION: This study found that the orbital volumetric crowding index was a more effective predictor of dysthyroid optic neuropathy than previously described computed tomography indexes were.http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1807-59322012000800006Dysthyroid optic neuropathyMultidetector computed tomographyGraves' orbitopathyVolume CT |
| spellingShingle | Allan C. Pieroni Gonçalves Lucas Nunes Silva Eloísa M. M. S. Gebrim Suzana Matayoshi Mário Luiz Ribeiro Monteiro Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures Clinics Dysthyroid optic neuropathy Multidetector computed tomography Graves' orbitopathy Volume CT |
| title | Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures |
| title_full | Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures |
| title_fullStr | Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures |
| title_full_unstemmed | Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures |
| title_short | Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures |
| title_sort | predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures |
| topic | Dysthyroid optic neuropathy Multidetector computed tomography Graves' orbitopathy Volume CT |
| url | http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1807-59322012000800006 |
| work_keys_str_mv | AT allancpieronigoncalves predictingdysthyroidopticneuropathyusingcomputedtomographyvolumetricanalysesoforbitalstructures AT lucasnunessilva predictingdysthyroidopticneuropathyusingcomputedtomographyvolumetricanalysesoforbitalstructures AT eloisammsgebrim predictingdysthyroidopticneuropathyusingcomputedtomographyvolumetricanalysesoforbitalstructures AT suzanamatayoshi predictingdysthyroidopticneuropathyusingcomputedtomographyvolumetricanalysesoforbitalstructures AT marioluizribeiromonteiro predictingdysthyroidopticneuropathyusingcomputedtomographyvolumetricanalysesoforbitalstructures |