Is retina affected in Huntington's disease? Is optical coherence tomography a good biomarker?

AIM OF THE STUDY: Comparative cross-sectional study of retinal parameters in Huntington's disease and their evaluation as marker of disease progression. CLINICAL RATIONALE FOR THE STUDY: Huntington's disease (HD) is a neurodegenerative disorder with dominant motor and neuropsychiatric symptoms. Involvement of sensory functions in HD has been investigated, however studies of retinal pathology are incongruent. Effect sizes of previous findings were not published. OCT data of the subjects in previous studies have not been published. Additional examination of structural and functional parameters of retina in larger sample of patients with HD is warranted. MATERIALS AND METHODS: This is a prospective cross-sectional study that included: peripapillary retinal nerve fiber layer thickness (RNFL) and total macular volume (TMV) measured by spectral domain optical coherence tomography (OCT) of retina, Pelli-Robson Contrast Sensitivity test, Farnsworth 15 Hue Color discrimination test, ophthalmology examination and Unified Huntington's disease Rating Scale (UHDRS). Ninety-four eyes of 41 HD patients examined in total 47 visits and 82 eyes of 41 healthy controls (HC) examined in total 41 visits were included. Analyses were performed by repeated measures linear mixed effects model with age and gender as covariates. False discovery rate was corrected by Benjamini-Hochberg procedure. RESULTS: HD group included 21 males and 20 females (age 50.6±12.0 years [mean ± standard deviation], disease duration 7.1±3.6 years, CAG triplet repeats 44.1±2.4). UHDRS Total Motor Score (TMS) was 30.0±12.3 and Total Functional Capacity 8.2±3.2. Control group (HC) included 19 males and 22 females with age 48.2±10.3 years. There was no statistically significant difference between HD and HC in age. The effect of the disease was not significant in temporal segment RNFL thickness. It was significant in the mean RNFL thickness and TMV, however not passing false discovery rate adjustment and with small effect size. In the HD group, the effect of disease duration and TMS was not significant. The Contrast Sensitivity test in HD was within normal limits and the 15-hue-test in HD did not reveal any specific pathology. CONCLUSIONS: The results of our study support possible diffuse retinal changes in global RNFL layer and in macula in Huntington's disease, however, these changes are small and not suitable as a biomarker for disease progression. We found no other structural or functional changes in retina of Huntington's disease patients using RNFL layer and macular volume spectral domain OCT and Contrast Sensitivity Test and 15-hue-test. CLINICAL IMPLICATIONS: Current retinal parameters are not appropriate for monitoring HD disease progression.

Cerebral venous thrombosis after a cesarean delivery.

Cerebral venous thrombosis (CVT) is a serious condition affecting mostly women. This report concerns two cases of women who developed CVT within 14 days of cesarean delivery. Magnetic resonance angiography of the brain (venous phase) is the best modality to diagnose the condition, and parenteral application of low-molecular-weight heparin is the most beneficial treatment. The first patient was found to have an elevated factor VIII level. In the second patient, homozygosity of the C677T mutation in the 5,10-methylenetetrahydrofolate reductase gene was found. The puerperal period and Cesarean Section (CS) are risk factors for thrombotic complications, including CVT. It is necessary to search for risk factors in a patient's history and within the group of at-risk patients to prolong preventive administration of low molecular weight heparin (LMWH). CVT (including puerperium related) is not a detrimental to future pregnancies.

New test of odor pleasantness in Parkinson's disease.

The New Test of Odor Pleasantness (NTOP) evaluates the hedonicity of olfactory stimulants. The aim of this study was to compare results of the NTOP, the Sniffin' Sticks test, and the Odorized Marker Test (OMT) in patients with Parkinson's disease (PD). The study sample comprised 30 PD patients (mean age 71±7.36 years) and the control group made up of 31 non-PD subjects (mean age 68±12.39 years). Sociodemographic data, medical history and tests of cognitive function were investigated. Olfaction was evaluated using the NTOP, Sniffin' Sticks test and OMT. The PD patients, compared with the control group, recorded significantly lower scores on all three tests: NTOP (p=0.00), Sniffin' Sticks (p=0.02), OMT (p=0.00). The NTOP was the test preferred by 55% of the subjects. This preference was more marked in the PD group. This study shows that the NTOP is a valuable method within the complex array of olfactory screening tools used in PD.

Changes of retina are not involved in the genesis of visual hallucinations in Parkinson's disease.

Parkinson's disease (PD) is characterized by motor and nonmotor symptoms. Nonmotor symptoms include primarily visual hallucinations (VH). The aim of our study was to establish whether patients with PD and visual hallucinations (PDH+) have structural changes of retina detected by an optical coherence tomography (OCT) in comparison with PD patients without visual hallucinations (PDH-). We examined 52 PD patients (18 with VH, 34 without VH) and 15 age and sex matched healthy controls. Retinal nerve fiber layer (RNFL) thickness and macular thickness and volume were assessed by OCT. Functional impairment of retina was assessed using 2.5% contrast sensitivity test. For OCT outcomes we analyzed 15 PDH+ and 15 PDH- subjects matched for age, gender, and PD duration. For contrast sensitivity we analyzed 8 pairs of patients matched for age, gender, and visual acuity. There was no significant difference in RNFL thickness and macular thickness and macular volume between 15 PDH+ and 15 PDH- subjects, and also between a group of 44 PD patients (both PDH+ and PDH-) and 15 age and gender matched healthy controls. No significant difference was found for 2.5% contrast sensitivity test values between PDH+ and PDH- subjects. Therefore we conclude that functional and structural changes in retina play no role in genesis of VH in PD.