Digital Image Analysis of the Angle and Optic Nerve: A Simple, Fast, and Low-Cost Method for Glaucoma Assessment

PURPOSE

To devise a simple, fast, and low-cost method for glaucoma assessment using digital image analysis of the angle and optic nerve in human subjects.

METHODS

Images from glaucoma and fundus assessment were used in this study, including color fundus photographs, standard optic nerve optical coherence tomography (OCT), and digital slit-lamp images of the angle/gonioscopy. Digital image conversion and analysis of the angle using ImageJ (NIH, USA) and adaptive histogram equalization contrast-limited AHE (CLAHE) to prevent noise amplification were implemented. Angle and optic nerve images were analyzed separately in the red, green, and blue (RGB) channels followed by 3D volumetric analysis of the degrees of angle depth and cup volume of the optic nerve. Horizontal tomogram reconstitution and nerve fiber detection methods were developed and compared to standard OCT images.

RESULTS

Digital slit-lamp angle images showed similar accuracy as standard anterior OCT measurements. Comparative analysis of RGB channels produced volumetric cup and horizontal tomogram, which closely resembled the 3D OCT appearance and B-scan of the cup, respectively. RGB channel splitting and image subtraction produced a map closely resembling that of the retinal nerve fiber layer (RNFL) thickness map on OCT.

CONCLUSIONS

While OCT imaging is rapidly progressing in the area of optic disc and chamber angle assessment, rising healthcare costs and lack of availability of the technology open a demand for alternative and cost-minimizing forms of image analysis in glaucoma. Volumetric, geometric, and segmentational data obtained through digital image analysis correspond well to those obtained by OCT imaging.

Cost-effectiveness of the triple procedure - phacovitrectomy with posterior capsulotomy compared to phacovitrectomy and sequential procedures

PURPOSE

To evaluate the cost-effectiveness of the triple procedure (phacovitrectomy + posterior capsulotomy, PhacoPPVc) compared to the double- (phacovitrectomy, PhacoPPV) or single sequential procedures.

METHODS

Prospective study on 31 eyes from 31 patients (mean age: 72.1 ± 9.1 years; 55% females) was performed with a preoperative decision to undergo only pars plana vitrectomy (PPV) (26%) or PhacoPPV (74%) and/or posterior capsulotomy based upon presence or absence of lens opacification or pseudophakia. Time during and between surgeries, surgical procedure codes, medical and transport costs, outcome and likelihood of complications after surgery were all included in the analysis. Societal perspectives and visual acuity were considered as measures of quality of adjusted life years (QALYs).

RESULTS

About 23 eyes underwent triple procedure and eight eyes underwent vitrectomy only (mean surgery times: 35.9 and 24.0 min, respectively). Posterior capsulotomy took on average 30 s, while preparation and cataract procedure took 13.0 min. The patients travelled on average 80km (average cost: $280.12) to the surgery unit. The average reimbursement fee for the day procedures ranged between $174.17 (YAG capsulotomy; Diagnosis Related Group (DRG): 0.034), $1045.48 (Phaco + intraocular lens (IOL); DRG: 0.204) and $1701.32 (PPV; DRG: 0.332). The combined procedures excluded lens and laser reimbursements, while the calculated reimbursements for the double/triple procedures were $2713.08/$2901.45, respectively, without significant loss of QALYs. PhacoPPVc was found to be unequivocally cost-effective, while PhacoPPV remained cost saving compared to sequential procedures.

CONCLUSION

This study confirms that the triple procedure has benefits to the patients, health institution and surgeon. For patients, it saves them travel and healing time; for health institution, it justifies the calculated higher costs and need for higher reimbursement for the double/triple procedures, which are cost saving.

Diabetic Retinopathy Screening Using Telemedicine Tools: Pilot Study in Hungary

Introduction. Diabetic retinopathy (DR) is a sight-threatening complication of diabetes. Telemedicine tools can prevent blindness. We aimed to investigate the patients' satisfaction when using such tools (fundus camera examination) and the effect of demographic and socioeconomic factors on participation in screening. Methods. Pilot study involving fundus camera screening and self-administered questionnaire on participants' experience during fundus examination (comfort, reliability, and future interest in participation), as well as demographic and socioeconomic factors was performed on 89 patients with known diabetes in Csongrád County, a southeastern region of Hungary. Results. Thirty percent of the patients had never participated in any ophthalmological screening, while 25.7% had DR of some grade based upon a standard fundus camera examination and UK-based DR grading protocol (Spectra™ software). Large majority of the patients were satisfied with the screening and found it reliable and acceptable to undertake examination under pupil dilation; 67.3% were willing to undergo nonmydriatic fundus camera examination again. There was a statistically significant relationship between economic activity, education and marital status, and future interest in participation. Discussion. Participants found digital retinal screening to be reliable and satisfactory. Telemedicine can be a strong tool, supporting eye care professionals and allowing for faster and more comfortable DR screening.

Behaviour does not fully explain the high risk of chronic liver disease in less educated men in Hungary

BACKGROUND

Hungary has among the highest mortality rates from chronic liver disease (CLD) and cirrhosis in Europe. Usually, conventional behavioural factors are hypothesized as the cause of the high risk of CLD.

METHODS

A case-control study was performed with 287 cases and 892 controls to study the relationship between socio-economic and behavioural factors and the risk of CLD. Liver disease was verified by physical examination and blood tests. Blood samples were collected for detecting hepatitis B, C and E virus infection. Information on exposure factors was recorded by the participating physicians and by self-administered questionnaire. Simple regression analysis was used to study the relationship between CLD/cirrhosis and potential risk factors as alcohol intake (amount and source), problem drinking, cigarette smoking, physical activity, viral hepatitis infections, socio-economic factors (education, financial and marital status). Multiple regression analysis was used to identify whether the effect of socio-economic factors is fully mediated by health behaviour (smoking, alcohol consumption, physical activity).

RESULTS

The univariate analysis showed that heavy alcohol consumption, problem drinking, former and heavy cigarette smoking, single, separated or divorced marital status, bad or very bad perceived financial status and lower education significantly increased the risk of CLD/cirrhosis. The effect of marital status and of education did not change after adjustment for behavioural factors, but the effect of perceived financial status disappeared.

CONCLUSIONS

The effect of low socio-economic status on the risk of CLD/cirrhosis is only partially explained by conventional behavioural risk factors in Hungary.