Brief Answer:
Field Defect can be due to Many Causes. Need Field Charting

Detailed Answer:
Hi,

Welcome to HealthCareMagic.com I am Dr.J XXXXXXX Anto Bruno Mascarenhas, and I am here to help you. I have read your question with care and understand that you are experiencing partial loss of sight in left eye. if you close your right eye and hold up a finger you can not see it past your nose (on the right side).

This means that you have got a visual field defect in Nasal Side of your Left Eye. In Other words, the Images (from the Right Side) that fall on your Left Eye are not carried over to brain

First and Foremost, I would like to congratulate you for having picked up this problem yourself quite early. Early diagnosis means that you have found the problem when it is fresh and this will definitely mean that the outcome will be good

If your Right Eye is Normal (you must have already checked it by closing your left eye) the this field defect is likely due to a

1. Problem in Your Retina (a part of eye) due to conditions like Retinitis Pigmentosa
2. Problem in your Optic Nerve Head (due to increased pressure)
3. Problem in your Optic Nerve (compression by some lesions inside orbit or canal)
4. Problem in your Optic Chiasma (Compression of the Lateral Side of the Chiasma) Usually by Aneurysm of Left Internal Carotid Artery

How to Proceed :
You have to consult your neurosurgeon, who will do
1. Clinical Examination to look at any other problems
2. Visual Field Testing by Confrontation method
3. Fundus Examination
4. Examination of other parameters of Vision
5. Visual Charting
6. CT Brain / MRI Brain
7. VEP

These tests will pinpoint the cause and once the exact cause has been found, we will treat the cause and you can be back to your normal

Hope you found the answer helpful.

If you need any clarification / have doubts / have additional questions / have follow up questions, then please do not hesitate in asking again. I will be happy to answer your questions.

Best Wishes for Speedy Recovery
Let me know if I can assist you further.
Take care.

-oOo-

PS 1 : After all your doubts have been cleared, kindly (a) Close this Question (b) Rate my Replies and (c) Give your Feedback.

PS 2 : In the future, for continuity of care, I encourage you to contact me directly in HealthCareMagic at http://bit.ly/askdrbruno

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