Preoperative Assessment of Crystalline Lens by A-Scan Quantitative Echography and Its Correlation with Phacoemulsification Parameters
Autor: | Doaa A. Mahmoud, Hanan S. Hegazy |
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Rok vydání: | 2019 |
Předmět: |
medicine.medical_specialty
Visual acuity genetic structures business.industry medicine.medical_treatment Ultrasound Phacoemulsification Cataract surgery eye diseases law.invention Lens (optics) Correlation law Ophthalmology medicine sense organs Posterior subcapsular cataract medicine.symptom business Ultrasound energy |
Zdroj: | The Egyptian Journal of Hospital Medicine. 77:4688-4691 |
ISSN: | 2090-7125 |
DOI: | 10.21608/ejhm.2019.45935 |
Popis: | Purpose: To evaluate the correlations between the total ultrasound energy consumed during phacoemulsification with various preoperative parameters, including the best- corrected distant visual acuity (BCDVA) and quantified metrics taken from A-scan ultrasound biometry. Patients and methods: A prospective observational interventional study included 40 eyes of 40 consecutive patients scheduled for cataract surgery. We assessed the lens internal reflectivity in the A-scan echograms within a range of 0% to 100%, and calculated the mean of all spikes. All eyes with cataract underwent clear corneal phacoemulsification. At the end of the operation we recorded the phacoemulsification time and mean percent power. The correlations of echographic and phacoemulsification data were assessed. Results: Quantitative echography in the 40 studied eyes with different types of cataract revealed acoustic reflections having various configurations according to the biomicroscopic type of cataract, i.e. cortical, nuclear and posterior subcapsular cataract. The mean spikes were 31.027% ± 25.5908, the mean lens thickness was 4.291 ± 0.6166, the mean best corrected distant visual acuity in decimal was 0.205±0.1435, the mean phaco power% was 6.400 ± 3.0701 and the mean phaco time is 84.225. There was statistically insignificant correlation between spikes% and phaco power% in the study group (p>0.05). There was statistically insignificant correlation between mean spikes% and lens thickness in the study group (p>0.05).There was statistically insignificant correlation between spikes% and phaco time (in seconds) in the study group (p>0.05). Conclusion: With regards to the predictive value of lens hardness changes in the acoustic properties identified by our method, it is not correlated with the ultrasound energy required intraoperatively. The A-scan is helpful for the clinical prediction of lens opacity location, but not predictive of lens hardness quantification. |
Databáze: | OpenAIRE |
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