Optical Coherence Tomography and Optical Coherence Tomography Angiography Findings in Multiple Sclerosis Patients.

In addition to ocular neurodegeneration in multiple sclerosis (MS), accompanying microvascular changes in the retina are thought to occur. In this study we sought to compare retinal neurodegenerative changes using optical coherence tomography (OCT) and microvascular changes using OCT angiography (OCTA) of MS patients and healthy controls. This cross-sectional study included 164 eyes of 83 MS patients and 114 eyes of 57 healthy control subjects. There were significant differences in retinal nerve fibre layer (RNFL), ganglion cell complex (GCC), and radial peripapillary capillary (RPC) vessel density (VD) between the MS group and the control group, but no significant differences in superficial capillary plexus (SCP) VD and deep capillary plexus (DCP) VD, foveal avascular zone (FAZ), non-flow area (NFA), and choriocapillary flow (CCF) values. Comparing the eyes with and without previous optic neuritis showed no significant differences in the OCT and OCTA measurements. A negative correlation was found between the expanded disability status scale score and disease duration and the RNFL and GCC values. A positive correlation was found between the RNFL and GCC values and the SCP VD and RPC VD. In MS patients, RPC VD values decreased in correlation with decreases in RNFL and GCC. This reduction increased as the disease duration and disability criteria increased. OCT and OCTA may be important biomarkers in MS.

MS and COVID-19 challenge: asymptomatic COVID-19 infection during treatment with cladribine.

BACKGROUND: The use of disease-modifying therapies (DMTs) in people with multiple sclerosis (pwMS) may affect COVID-19 infection outcomes due to DMTs' immunomodulatory and immunosuppressive effects on immune response. The yet unknown issues are both the early response to the infection, as well as the post-infection development of immunity against the virus under these treatments due to their interaction with the immune system. METHODS: We report two asymptomatic cases of COVID-19 in patients with relapsing-remitting multiple sclerosis (RRMS) shortly after starting cladribine therapy, both developed anti-SARS-CoV-2 antibody response. RESULTS: Patients with MS who are under newly initiated treatment with cladribine tablets may experience an asymptomatic COVID-19 infection and they may develop immunity against SARS-CoV-2. CONCLUSION: These observations raise the probability that DMTs with immunosuppressive effects, such as cladribine, may be considered as a treatment option for selected MS patients with high disease activity during the COVID-19 pandemic.

Epicardial Adipose Thickness and Neutrophil Lymphocyte Ratio in Acute Occlusive Cerebrovascular Diseases.

OBJECTIVES: We investigate the relationship between the severity of vascular disease and epicardial adipose tissue thickness(EAT-t) and the neutrophil/lymphocyte (NEU/LY) ratio in acute stroke patients. METHODS: Seventy-six patients and 38 healthy controls were included in the study. Strokes were divided into three groups: lacunar infarction, middle cerebral artery infarction (MCA), and other arterial infarcts. Patients were assessed using the GCS (Glasgow coma scale) and NIHSS (National Institutes of Health Stroke Scale) scales. In addition to laboratory measurements, EAT-t was evaluated in all patients by using echocardiography. RESULTS: The EAT-t value and NEU/LY ratio were higher in the patient group than in the control group. The MCA group was found to have a significantly higher NEU/LY ratio than the lacuna group (p = 0.017) as well as the other patient (p = 0.025) group. There was a positive correlation of NIHSS score with EAT-t (r = 0.291; p = 0.013), and NEU/LY ratio (r = 0.289; p = 0.014). CONCLUSION: The EAT-t and NEU/LY ratio were high in patients with acute ischemic stroke patients. The higher ratio of NEU/LY compared to other infarcts in the MCA group. These findings support the relationship between acute ischemic stroke severity and inflammation .

Attitudes of neurology specialists toward older adults.

OBJECTIVE: Attitude of healthcare providers toward older people is very important in the aging world. Neurologists contact older adults very frequently. We aimed to investigate the attitudes of neurologists toward older adults. MEASUREMENTS: We recorded participants age; sex; duration of clinical practice in neurology; existence of older adult relatives; and history of geriatrics education, nursing home visits, older adult patient density in their clinical practice, and participation in voluntary public activities. UCLA Geriatrics Attitude Scale was used to evaluate participants' attitudes. RESULTS: A total of 100 neurologists participated in this study. Seventy-seven percent had positive, 3 % had neutral, and 20 % had negative attitudes. Twenty-seven percent of the participants had history of geriatrics education, and these participants tended to have a higher rate of positive attitudes. Neurologists with positive attitudes tended to be older than those with negative attitudes. Participants with history of living with older adult relatives had lower rates of positive attitudes. The most common diagnoses of the patients the participants encountered were stroke and dementia. Independent factors associated with positive attitudes were history of geriatrics education and older age. History of living with older relatives tended to have a negative effect. Most of the negative items of the attitude scale were associated with the natural course and behavior of the common diseases in neurology practice. CONCLUSIONS: Generalization of geriatrics education may translate into a better understanding and improved care for older patients. Development of instruments and implementation of qualitative studies to assess attitudes of neurologists toward older adults are needed.

Restless-legs syndrome and insomnia in hemodialysis patients.

AIM/BACKGROUND: Restless legs syndrome (RLS) is a common neurological movement disorder which is commonly seen in hemodialysis (HD) patients. Insomnia, depression, and anxiety disorders frequently show concurrence. In this study, we aimed to investigate RLS and insomnia prevalence and related factors in HD patients. SUBJECTS AND METHODS: Patients who were under HD treatment and healthy controls with similar mean age, sex ratio, and hypertension and diabetes mellitus frequency were included in this study. Depression, insomnia, and daytime sleepiness assessments were performed by using Beck Depression Inventory, Insomnia Severity Index, and Epworth Sleepiness Scale. The diagnosis of RLS was made using the International RLS Study Group consensus criteria. RESULTS: About 156 HD patients and 35 controls were enrolled. The mean age was 50.6 in the HD group and 49.7 in the control group. Female sex was 43.9% in the HD group and 57.1% in the control group. RLS was significantly more frequent in HD patients compared with controls. The rate of sub-threshold insomnia and insomnia with moderate severity was higher in HD patients. While insomnia severity score and diabetes mellitus were significantly associated with the presence of RLS, depression, RLS, older age, and being under HD treatment were independently associated with insomnia severity. CONCLUSIONS: HD patients commonly have RLS and insomnia. Insomnia and diabetes mellitus seem to be major factors underlying RLS in HD patients. Furthermore, depression and RLS seem to be closely related to insomnia in these patients. Treatment of depression, insomnia, and RLS may be beneficial to improve quality of life in HD patients.

Hand Grip Strength as a Predictive Tool for Upper Extremity Functionality, Balance, and Quality of Life in People With Multiple Sclerosis.

BACKGROUND: Upper extremity strength and function are rarely assessed in routine multiple sclerosis (MS) care. This study aimed to evaluate hand muscle strength and functionality in individuals with MS and investigate correlations with upper extremity function, cognitive status, health-related quality of life (HRQOL), and balance. METHODS: A cross-sectional study was conducted with 45 consecutive individuals with MS between the ages of 18 and 65. Upper limb motor strength was evaluated using a hand grip strength dynamometer. Upper limb functional capacity was assessed using the Nine-Hole Peg Test (9HPT) and the Duruoz Hand Index (DHI). Balance, coordination, and falls were measured with the Berg Balance Scale (BBS), Falls Efficacy Scale (FES), and the 30-Second Chair Stand Test (30CST). Cognitive function was evaluated using the Montreal Cognitive Assessment instrument and the Symbol Digit Modalities Test. Level of HRQOL was assessed using the self-reported 54-item MS Quality of Life-54 questionnaire. RESULTS: Out of the 45 participants (80% women, mean age 36.6 ± 8.6 years), higher hand grip dynamometer measures were strongly correlated with better DHI, 9HPT, BBS, FES, and 30CST scores. In the regression analysis, a 1-unit increase in dynamometer measures led to a 0.383 increase in overall HRQOL score. CONCLUSIONS: This study demonstrates that increased hand grip strength (HGS) is associated with better hand functionality, balance, and HRQOL in individuals with MS. It provides evidence to support more systematic measurement of HGS in the care of people with MS.

Recurring disease activity in relapsing remitting multiple sclerosis: The multicenter RDA-RMS study.

BACKGROUND: This study investigates the gap in understanding the dynamics of recurring disease activity (RDA) in RRMS patients after fingolimod (FGL) treatment discontinuation. The aim is to investigate RDA in RRMS patients after stopping FGL, aiming to improve management and comprehension of disease progression post-treatment. METHODS: In this multicenter, retrospective study, data from 172 of 944 RRMS patients aged 18-55, across nine centers in Turkey, who discontinued FGL treatment, were analyzed. The collected data included EDSS scores, annualized relapse rates (ARR), lymphocyte counts, and MRI findings, with follow-up assessments conducted at 6 months, 1 year, and up to 2 years. RESULTS: RDA was observed in 31.9 % of patients, with incidences of rebound and reactivation at 20.3 % and 11.6 %, respectively. Factors like younger age, longer treatment duration, lower lymphocyte counts, and higher lesion burden increased RDA risk. Notably, 52.9 % of pregnant patients experienced RDA (16.4 % of the overall RDA group), with rebound occurring in six and reactivation in three. Patients with RDA had longer medication-free intervals and increased ARR. Discontinuation reasons varied, with disease progression linked to a lower RDA risk. CONCLUSION: Findings highlight the necessity for personalized management and vigilant monitoring after FGL discontinuation in RRMS patients, offering critical insights into RDA risk factors, and the complex interplay between treatment cessation, pregnancy, and disease progression.

Clinical and demographic characteristics of late-onset multiple sclerosis: LOMS-TR study.

OBJECTIVES: Multiple sclerosis (MS), which is known as a young-adult age disease, is called late-onset MS (LOMS) when it occurs at the age of 50 and older. In our study, we aimed to analyse the clinical and demographic characteristics, comorbidities, diagnostic and treatment challenges and prognosis of LOMS. METHODS: In a retrospective analysis of 136 patients diagnosed with multiple sclerosis (MS) after the age of 50, based on the 2017 McDonald criteria, and who were under observation in eight distinct MS centers across Turkey; demographic information, clinical characteristics of the disease, oligoclonal band (OCB) status, initial and current Expanded Disability Status Scale (EDSS) values, administered treatments, and the existence of spinal lesions on magnetic resonance imaging (MRI) were investigated. RESULTS: The mean age of the 136 patients was 60.96±6.42 years (51-79), the mean age at diagnosis was 54.94±4.30 years, and 89 (65.4 %) of the patients were female. Most of the cases, 61.1 % (83) had at least one comorbidity. In 97 patients who underwent lumbar puncture (LP), OCB positivity was observed in 63.6 %. In 114 patients (83.8 %), spinal lesions were detected on MRI. Eighty-seven patients had relapsing-remitting MS (RRMS) (64 %), 27 patients had secondary progressive MS (SPMS) (19.9 %), and 22 patients had primary progressive MS (PPMS) (16.2 %). The mean EDSS at the time of diagnosis was 2.44±1.46, and the mean current EDSS was 3.15±2.14. CONCLUSIONS: In LOMS patients, the rates of delay in the diagnostic process, treatment disruption and progressive disease are higher than in the general MS population. The high rates of LP applying and OCB positivity of this study may indicate the habit of looking for clear evidences in advanged age in our country. This situation and comorbidities may cause a delay in diagnosis and eliminates the window of opportunity for early diagnosis. Although the high number of spinal lesions is a known marker for progressive disease, it is an issue that needs to be discussed whether the increased frequency of progressive course at older ages is due to the nature of the disease or immune aging itself.

The global patient-reported outcomes for multiple sclerosis initiative: bridging the gap between clinical research and care - updates at the 2023 plenary event.

Significant advancements have been achieved in delineating the progress of the Global PROMS (PROMS) Initiative. The PROMS Initiative, a collaborative endeavor by the European Charcot Foundation and the Multiple Sclerosis International Federation, strives to amplify the influence of patient input on MS care and establish a cohesive perspective on Patient-Reported Outcomes (PROs) for diverse stakeholders. This initiative has established an expansive, participatory governance framework launching four dedicated working groups that have made substantive contributions to research, clinical management, eHealth, and healthcare system reform. The initiative prioritizes the global integration of patient (For the purposes of the Global PROMS Initiative, the term "patient" refers to the people with the disease (aka People with Multiple Sclerosis - pwMS): any individual with lived experience of the disease. People affected by the disease/Multiple Sclerosis: any individual or group that is affected by the disease: E.g., family members, caregivers will be also engaged as the other stakeholders in the initiative). insights into the management of MS care. It merges subjective PROs with objective clinical metrics, thereby addressing the complex variability of disease presentation and progression. Following the completion of its second phase, the initiative aims to help increasing the uptake of eHealth tools and passive PROs within research and clinical settings, affirming its unwavering dedication to the progressive refinement of MS care. Looking forward, the initiative is poised to continue enhancing global surveys, rethinking to the relevant statistical approaches in clinical trials, and cultivating a unified stance among 'industry', regulatory bodies and health policy making regarding the application of PROs in MS healthcare strategies.

Effects of disease-modifying therapies on lipid parameters in patients with multiple sclerosis.

BACKGROUND: Cholesterol and lipids are essential components of nerve cells. Myelin synthesis and stabilization is a cholesterol-dependent process. It has been shown in several studies that high plasma cholesterol levels may be associated with clinical deterioration in Multiple Sclerosis (MS). There is scarce information about the effects of disease-modifying treatment (DMTs) on lipid profile. In this study, we aimed to investigate the effect of DMTs on plasma lipid profiles in MS patients. METHOD: The records of 380 MS patients who were still under follow-up were analyzed in terms of age, sex, disease duration, EDSS scores, serum lipid levels, and used DMTs. The data of patients receiving Interferon (n = 53), Glatiramer acetate (n = 25), Fingolimod (n = 44), Teriflunomide (n = 24), Dimethyl fumarate (n = 7) and Ocrelizumab (n = 14) were compared with the data of control group (n = 53). RESULTS: A total of 220 patients, 157 women, and 63 men, were included in the study. The average age of the participants in the study was 39.83 ± 10.21 years, mean disease duration was 8.45 ± 6.56 years, and the EDSS score was 2.25 ± 1.97. Although, Lipid parameters were higher in MS patients using Fingolimod the difference cannot reach the statistical significance. CONCLUSION: No significant relationship was found between the DMTs that MS patients had been using for the last six months and their cholesterol levels.

NOTCH3 Variants in Patients with Suspected CADASIL.

Background: Cerebral autosomal dominant arteriopathy with subcortical infarctions and leukoencephalopathy (CADASIL) is the most common hereditary form of cerebral small vessel disease. It is clinically, radiologically, and genetically heterogeneous and is caused by NOTCH3 mutations. Methods: In this study, we analyzed NOTCH3 in 368 patients with suspected CADASIL using next-generation sequencing. The significant variants detected were reported along with the clinical and radiological features of the patients. Results: Heterozygous NOTCH3 changes, mostly missense mutations, were detected in 44 of the 368 patients (~12%). Conclusions: In this single-center study conducted on a large patient group, 30 different variants were detected, 17 of which were novel. CADASIL, which can result in mortality, has a heterogeneous phenotype among individuals in terms of clinical, demographic, and radiological findings regardless of the NOTCH3 variant.

Clinical and Demographic Characteristics and Two-Year Efficacy and Safety Data of 508 Multiple Sclerosis Patients with Fingolimod Treatment.

Introduction: Fingolimod is the first oral immunomodulatory treatment used as secondary care therapy in the treatment of multiple sclerosis for the last 10 years. The objective of our study is to reveal the experiences of the first generic fingolimod active ingredient treatment in different centers across Turkey. Method: The first generic fingolimod efficacy and safety data of patients followed-up in 29 different clinical multiple sclerosis units in Turkey were analyzed retrospectively. Data regarding efficacy and safety of the patients were transferred to the data system both before the treatment and on the 6th, 12th and 24th month following the treatment. The data were analyzed using the IBM SPSS 20.00. P value of <0.05 was considered to be statistically significant. Results: A total of 508 multiple sclerosis patients, 331 of whom were women, were included in the study. Upon comparing the Expanded Disability Status values before and after the treatment, a significant decrease was observed, especially at month 6 and thereafter. Since bradycardia occurred in 11 of the patients (2.3%), the first dose had to be longer than 6 hours. During the observation of the first dose, no issues that could prevent the use of the drug occured. Side effects were seen in 49 (10.3%) patients during the course of fingolimod treatment. Respectively, the most frequent side effects were bradycardia, hypotension, headache, dizziness and tachycardia. Conclusion: The observed results regarding efficacy and safety were similar to clinical trial data in the literature and real life data in terms of the first equivalent with fingolimod active ingredient.

Erratum: Clinical and Demographic Characteristics and Two-Year Efficacy and Safety Data of 508 Multiple Sclerosis Patients with Fingolimod Treatment.

[This corrects the article on p. 23 in vol. 60, PMID: 36911568.].

The Socioeconomic and Psychological Impact of the COVID-19 Pandemic on People with Multiple Sclerosis in Turkey.

Introduction: Various restrictions due to the coronavirus infection have affected working life globally. People with multiple sclerosis (pwMS) have several difficulties in social life, patient follow-up, and receiving treatments. In this study, we aimed to evaluate the experiences of pwMS during the COVID-19 pandemic. Method: We developed a 50-question survey aiming to determine fears, anxieties, and the problems experienced by patients regarding their diseases and social lives during the COVID-19 pandemic. The questionnaire was released online via the Turkish MS Society website, local MS societies websites, and social media accounts. Only the answers of the patients who filled out the questionnaire completely were evaluated. Results: In total, 6008 patients took the survey, and 3255 of them completed the questionnaire. Among all, 378 patients (11.6%) were positive for COVID-19. The most common COVID-19-related symptom was fatigue (48.4%). The routine medical follow-up was interrupted in 61.4% and the medication was discontinued in 14% of the patients. Approximately 25% of the patients reported different symptoms related to relapse activity. The main concern of the patients related to the COVID-19 pandemic was the disruption of the health of the ones they loved. Among all the patients, 4.4% lost their jobs. Conclusion: Our data showed that the COVID-19 pandemic strongly affected the working lives of pwMS. Also, the pandemic changed the attitudes of patients and neurologists. Therefore, the long-term effects of the COVID-19 pandemic on disease approach, patient follow-up, social conditions, and working life should be monitored.

Restless legs syndrome/Willis-Ekbom disease in multiple sclerosis: a contributing factor for anxiety, disability, sleep disorder, and quality of life.

BACKGROUND: Restless legs syndrome (RLS) is one of the most common and burdensome sleep disorders in the course of multiple sclerosis (MS). OBJECTIVE: To evaluate common MS-related symptoms and consequences between groups with and without RLS and further assess the association of quality of life determinants with RLS symptom severity. METHODS: According to their RLS status, 46 relapsing-remitting MS patients were divided into MS-RLS+ (n=19) and MS-RLS- groups (n=27). Specific questionnaires were administered to assess the patients' health-related quality of life (HRQoL), fatigue levels, sleep quality, daily sleepiness, anxiety, and depression symptoms. Functional capacity was examined using the Expanded Disability Status Scale (EDSS). RESULTS: The prevalence of RLS was 41.3%. Compared to the MS-RLS- group, those with RLS had higher EDSS scores, more cranial and spinal lesions, longer disease duration, and were older. In the MS-RLS+ group, symptom severity scores were positively correlated with higher anxiety and poorer sleep quality. The symptom severity score was negatively correlated with mental HRQoL and pain scores. CONCLUSION: In conclusion, the findings of the current study indicate the negative impact of RLS on functional capacity, anxiety, sleep quality, and mental HRQoL of MS patients. Further studies using more accurate diagnostic strategies for identifying RLS and other sleep disorders are necessary to clarify the association of MS with RLS and explore relevant clinical implications.

The prognostic value of demyelinating electrophysiologic findings and cerebrospinal fluid protein levels in acute inflammatory demyelinating polyneuropathy.

BACKGROUND: Guillain-Barre syndrome is an acute immune-mediated polyneuropathy characterized by rapidly evolving symptoms and disability. Cerebrospinal fluid analysis and electrophysiological studies are crucial in the diagnosis of this syndrome. OBJECTIVE: To evaluate the prognostic value of the type and number of demyelinating findings and cerebrospinal fluid protein levels in patients with acute inflammatory demyelinating polyneuropathy. METHODS: We retrospectively analyzed electrophysiological data and cerebrospinal fluid of 67 consecutive patients with acute inflammatory demyelinating polyneuropathy from Istanbul, Turkey (2011-2019) studied ≤ 24 hours post-onset. RESULTS: The patients who met a higher number of demyelinating criteria had increased disability scores in the first day and first month, and higher cerebrospinal fluid protein levels were correlated with worse prognosis both on the first day and the first month. However, the disability scores did not correlate with any single specific criterion, and no significant correlation was found between the number of satisfied criteria and cerebrospinal fluid protein levels. CONCLUSIONS: The number of demyelinating criteria that are met and high cerebrospinal fluid protein levels at the disease onset may be valuable prognostic markers. More systematic studies conducted with serial nerve conduction studies are required to highlight the roles of the suggested criteria in clinical practice.

Associations Between Olfactory Impairment and Cognitive Functions in Patients with Parkinson Disease.

INTRODUCTION: Olfactory impairment and cognitive impairment are common non-motor symptoms in Parkinson's disease (PD). Olfactory impairment may be present even many years before the main symptoms of the disease develop. The associations between olfactory loss and cognition in PD are evaluated in this study. METHODS: 31 patients with PD and 31 healthy subjects were included in this study. The Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn and Yahr Scale (H&Y Scale) were administered to all subjects. Butanol threshold test and Sniffin'Sticks test were used to assess olfaction. The Mini Mental State Examination (MMSE) and Clock Drawing Test (CDT) and Stroop Color Word Test (SCWT) were used to assess cognition. RESULTS: The Sniffin'Sticks test scores were significantly lower in the Parkinson group in comparison to the control group (p<0.001). The rate of anosmia was 90% in the PD group while this rate was found to be 54.8% in control group (p=0.005). A significant correlation was found between butanol test scores and stoop 5 and 5 errors. Significant correlations were found between the Sniffin'Sticks scores and MMSE scores (p=0.047) and orientation (p=0.041) and language (p=0.003) functions of the MMSE test. Worse olfaction was associated with worse memory. CONCLUSIONS: In PD, olfactory impairment correlates with cognitive impairment and olfactory tests may be used to predict the likelihood of developing dementia in this patient population.

Delayed diagnosis of a neuroBehçet patient with only brainstem and cerebellar atrophy: literature review.

We report a 34-year-old male neuroBehçet's Disease (NBD) patient with atypical magnetic resonance imaging (MRI) findings, whose behavioral problems were followed by progressive neurological symptoms. The patient was hospitalized due to forgetfulness, irritability, behavioral dyscontrol and a choking sensation. T2-weighted MRI showed prominent atrophy of cerebellar hemispheres, the cerebellar peduncle, the midbrain and the pons. He was diagnosed with NBD after an evaluation of his medical history together with neuropsychiatric and laboratory findings. There are few reports of NBD with only brainstem and cerebellar atrophy. We discuss our patient in the context of the four previously reported cases. In NBD without evident mucocutaneo-ocular symptoms, neurologists should always consider the medical and family history. Early diagnosis of NBD helps to initiate appropriate treatment, thereby modulating the course of the disease and preventing complications.

Assessment of Neurodegeneration by Optical Coherence Tomography and Mini-Mental Test in Parkinson's Disease.

BACKGROUND: Parkinson's disease is a neurodegenerative disease. Cognitive disorders and retinal degeneration may occur during the early stages of the disease. Retinal degeneration and cognitive findings can be assessed easily with optical coherence tomography and mini-mental test, respectively. MATERIALS AND METHODS: Twenty-two patients who are being followed-up with Parkinson's disease and 22 healthy controls have been included in the study. The Unified Parkinson's Disease Rating Scale (UPDRS) and Hoehn-Yahr staging of the patients have been conducted at the time of admission. Retinal nerve fiber layer analysis and ganglion cell thickness (ganglion cell complexes [GCCs]) were evaluated through optical coherence tomography (OCT). And at the same time, we aimed to compare the stage of the disease, the UPDRS score and the duration of the disease with OCT and cognitive functions by mini-mental test. RESULTS: Mini-mental test total score value (P = 0.025) and language value (P = 0.021) were lower in the patient group compared to the control group. In patients, there is a reverse significant correlation between UPDRS-T and GCC-left-superior (r = -0.495; P = 0.026), GCC-left-inferior (r = -0.517; P = 0.019), and GCC-left-to (r = -0.508; P = 0.022). There is a significant parallel relation between recall and RFNL-right-mean (r = 0.626; P = 0.039). CONCLUSION: Our findings indicate that the neurodegeneration continues multisystemically and neurodegeneration increases simultaneously with the disease. OCT, which is a noninvasive method, can be used as an indicator of neurodegeneration in patients with Parkinson's disease.