European Journal of Cardiovascular Medicine

Optic neuritis is when inflammation in your optic nerve causes pain, vision loss and other symptoms. This condition has strong links to chronic conditions like multiple sclerosis and other autoimmune diseases. Timely diagnosis and treatment may help optic neuritis and limit or delay more severe long-term effects or conditions.  Optic neuritis is swelling of the eye’s Optic Nerve. The optic nerve carries light signals from the back of your eye to your brain so you can see. If the optic nerve is swollen, damaged or infected, you cannot see clearly.

Doctors do not know for sure what causes optic neuritis. This condition may be caused by the body’s immune system attacking optic nerve tissue by mistake. It seems more likely to happen in people who have had viral problems like mumps, measles, flu or multiple sclerosis, among others.

Optic neuritis prevalence in India is difficult to pinpoint precisely due to limited large-scale epidemiological studies. However, Indian studies suggest a prevalence of approximately 1.33/100,000, while NMO, another cause of optic neuritis, has a reported incidence of 9.5% in some studies. Additionally, MS, often associated with optic neuritis, constitutes 0.32% to 1.58% of neurology admissions in Indian hospitals.

The incidence of optic neuritis, meaning the rate of new cases, varies worldwide, but generally falls between 1 and 5 cases per 100,000 individuals per year Optic neuritis most commonly affects young adults, typically between 20 and 50 years old, with an average age of onset around 32. The incidence is also linked to geographic location, with higher rates observed in temperate climates and lower rates in regions near the equator, correlating with the distribution of MS. Optic neuritis is more prevalent in Caucasians compared to other ethnic groups. However, in some Asian and African populations, optic neuritis may present with different characteristics and be more associated with conditions like neuromyelitis optica (NMO) rather than MS.

One study reported an annual incidence of 8.1 per 100,000 in the total population, with a higher incidence rate in females (16.9) compared to males (6.5). Another study found that females were affected at a higher rate in nearly all age groups, with the greatest female-to-male prevalence odds ratio in those aged 45-54.  Optic neuritis is more prevalent in Caucasians compared to other ethnic groups. However, in some Asian and African populations, optic neuritis may present with different characteristics and be more associated with conditions like neuromyelitis optica (NMO) rather than MS.

Aims& Objective

Objective of this study was to evaluate the optic nerve characteristics in patients with optic neuritis among general population.

The study was conducted in a tertiary hospital. After obtaining institutional ethical committee approval It was a Observational prospective study conducted on 35 patients with optic neuritis in the department of Ophthalmology, at a tertiary care centre, from May2024 to November 2024. The institute Ethics Committee approval was obtained before starting the sample collection. A written and informed consent was taken from the patient regarding the study in his/her vernacular language and English. In this study Patients were subjected to: A detailed history of sign & symptoms and its duration. Detailed history of systemic diseases and its duration, medication were noted. Patients were subjected to General physical examination, and ocular examination. Participants Visual acuity was recorded by Snellen’s chart, Slit lamp bio-microscopy of anterior segment was done, Pupillary reactions were noted. Participants Detailed examination of the posterior segment was done with Direct and indirect ophthalmoscopy and also with 90D Lens. Colour vision test was done with Ishihara pseudo-isochromatic plates. Visual field with full threshold HVF 30-2 test done. MRI brain imaging done. The results of these 30 patients were collected, tabulated and analysed. The data collected was entered in excel spread sheet. The data was analysed by using SPSS statistical software version 20. Statistical analysis in the form of percentages was done. Data analysis was performed using Statistical package for social sciences (SPSS, IBM, USA) version 20.0. Results were reported as mean ± standard deviation for quantitative variables.

Comparison with respect to demographic data and duration of surgery was done using one-way ANOVA test. Comparison of three groups with mean HR, MAP and mean temperature was done using one-way ANOVA test. Pair-wise comparison of three groups with MAP and HR at different points of time was done by Tukeys multiple post hoc testing. Categorical data were compared using Chi-square test. The value of P < 0.05 was considered statistically significant.

Optic neuritis most commonly affects young adults, typically between 20 and 50 years old, with an average age of onset around 32. The incidence is also linked to geographic location, with higher rates observed in temperate climates and lower rates in regions near the equator, correlating with the distribution of MS.  Optic neuritis varies worldwide, with an estimated annual incidence of 1 to 5 cases per 100,000 individuals. However, the incidence may be higher in populations with a greater prevalence of multiple sclerosis, as optic neuritis is often a presenting feature of this demyelinating disease. Women are more commonly affected by optic neuritis than men, with a female-to-male ratio of approximately 5.76:1. This pattern is consistent with the gender distribution seen in multiple sclerosis, where women are also disproportionately affected. The higher incidence in women is thought to be related to the autoimmune nature of the disease, as many autoimmune disorders are more prevalent in female individuals [2] .Optic neuritis is more common in females than males and is about 60% (Figure 2). And majority of female participants develop to Multiple sclerosis in   compare to male. Most common age group is 26- 35 years and it is 43% followed by 45-55years which is 29% (Figure 1). More vulnerable age group in this study 25 to 35 age group. In our study it was found that fundus examination, oedematous disc with the blurred disc margins was the most common finding seen in 71% of the patients (Table 1). Hyperemic disc is 11.4%. Colour vision defects were present in all the patients, Red-Green colour defect was more common and was seen in many patients. Visual fields showed severely depressed fields in majority patients. MRI was normal in 81 % patients, but in majority of patients features suggestive of retrobulbar optic neuritis like hyperintense lesions in retrobulbar optic nerve was found.

Table 1: Fundus disc findings of the patients

In this study females are significantly more likely to be affected than males, with a female-to-male ratio of approximately 5.76 :1. Here odds ratio is 5.76 with %of CI[1.3 to 25.4]  This means that for every one man affected, about 5 women are affected. The exact odds ratio varies slightly depending on the study, but the overall trend is consistent: women are disproportionately affected.  And similar study have been done in many university worldwide and similar data have been shown.it has ben seen in table no 2. And here p value is  0.02 which is <0.05 so this study is significant and association of gender with multiple sclerosis in optic neuritis patient. And its has been also shown that optic neuritis patient in female gender are more chance to develop multiple sclerosis as compare to male patient.

Table 2: Optic neuritis developed into Multiples sclerosis in respect Gender

Table: 3

Optic neuritis is a vision-threatening disorder and often the first symptom of demyelinating diseases such as multiple sclerosis. Infections, autoimmune diseases, and certain medications may also trigger this condition. Symptoms typically include sudden vision loss, eye pain (especially with eye movement), and changes in colour perception. Some individuals may also experience the Marcus Gunn pupil, an abnormal response to light [2]

Diagnosis involves a thorough clinical evaluation and the use of advanced imaging modalities, particularly optical coherence tomography and magnetic resonance imaging. Blood tests may be taken to exclude other conditions.[3] Management often starts with high-dose intravenous corticosteroids to reduce inflammation and accelerate recovery.[4] Optic neuritis most commonly affects young adults, typically between 20 and 50 years old, with an average age of onset around 32. The incidence is also linked to geographic location, with higher rates observed in temperate climates and lower rates in regions near the equator, correlating with the distribution of MS [5][6][7]. The optic nerve function characteristics studied are in the form of visual acuity which is done by Snellen’s chart; colour vision by Ishihara plates; contrast sensitivity by Pelli Robson chart; visual fields by Humphreys visual field 30-2; Visual Evoked Potential VEP; lastly MRI brain.[8] In a study conducted by D. Pau et al., 2 they have concluded that the patients with acute demyelinating ON are healthy young adults typically and most of the patients age range was between 20-45 years of age, with female preponderance by a ratio of 3:1, their study findings are corelating with our study [9][10]. Beck R et al. 3 in their study showed afemale (77%) predominance, which is in correlation with our study. In a study conducted by Schneck ME et al. 4 on colour vision defect type, showed mixed red-green defects [RG] and blue-yellow [BY] colour defects [11-17]. Verriest et al. 5 and Silverman SE et al. 6 also shows RG>BY colour defects. In this study is in correlation with these studies. Katz b et al., 7 in their study concluded that blue, yellow defects were the majority at the time of the acute attack, whereas at six months, red/green defects were the majority. [18-22] .

Griffin et al., 8 study concluded that the number of errors increased with greater residual optic nerve damage. Kuchenbecker J et al. 9 have written, that the number of incorrectly identified plates correlated with a decrease in visual acuity. They used advanced technology for doing the test known as the web test. They said that, altering the combination of plates may be used as a next step by using the web-based an [23-29]. Our study is in correlates with these studies.

Patients with optic neuritis typically present with a sudden onset of vision loss in 1 eye, although bilateral involvement can occur. The degree of visual loss varies, ranging from mild visual blurring to complete blindness in the affected eye. Pain, especially with eye movement, is a hallmark symptom of optic neuritis and often precedes visual impairment by a few days. [30-35]

Besides visual loss, patients may experience reduced colour vision (dyschromatopsia) and contrast sensitivity. A relative afferent pupillary defect (RAPD) is often present when the condition affects only 1 eye or presents asymmetrically in bilateral cases [36-41]. During an ophthalmologic examination, the optic disc may appear normal, indicating retrobulbar neuritis, or show swelling, known as papillitis, if the inflammation involves the anterior part of the optic nerve [42-45] .

In another study by Alshualb WB et al., 14 where they compared VEP abnormalities in multiple sclerosis and optic neuritis have found that decreased amplitude and P100 and N145 latencies were prolonged in optic neuritis and also in confirmed MS patients. Our study is correlating with their study, P100 latencies were prolonged in our study, although our study didn’t have any multiple sclerosis associated patients [46-49]. 

In this study females are significantly more likely to be affected than males, with a female-to-male ratio of approximately 5.76 :1. This means that for every one man affected, about 5 women are affected [50-52] The exact odds ratio varies slightly depending on the study, but the overall trend is consistent: women are disproportionately affected.  And similar study has been done in many universities worldwide and similar data have been shown.it has been seen in table no 2. And here p value is 0.02 which is <0.05 so this study is significant and association of gender with multiple sclerosis in optic neuritis patient.  Similar study and result shown in research article Guier CP, Kaur K, Stokerian TJ. Optic Neuritis.

Optic neuritis most commonly affects young adults, typically between 20 and 50 years old, with an average age of onset around 32. The incidence is also linked to geographic location, with higher rates observed in temperate climates and lower rates in regions near the equator, correlating with the distribution of MS. And women are more prone to develop Multiple sclerosis as compared to male among optic neuritis. Females are significantly more likely to be affected than males, with a female-to-male ratio of approximately 5.76 :1. This means that for every 1 man affected, about 5 women are affected. Proper diagnosis of the disease, correct treatment at right time is necessary. The major concern lies with the future recurrences and association of optic neuritis with multiple sclerosis and /other demyelinating disorders, because once the patient receives the treatment and gets relieved he/she starts neglecting it. Optic neuritis, particularly typical cases, is more common in women. Combined approach for treatment with neurologist is required to make them aware of disease process, treatment & to prevent recurrences. Most cases of optic neuritis resolve spontaneously, with vision gradually returning to normal within weeks or months. However, in some cases, steroid medications may be used to reduce inflammation and potentially speed up recovery. in some cases, steroid medications may be used to reduce inflammation and potentially speed up recovery.

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