Locations of the aqueous humour

[Tom215]

Now I'm troubled with exact locations of aqueous humour. I've known the locations from wikipedia http://en.wikipedia.org/wiki/Aqueous_hum... Wkipedia says it is within the cornea. Today I went to the eye doctor's and asked him. He answerd it's around any eye structures. Which knowledge is true?

[John C Hagan III, MD, FACS, FAAO]

Aqueous humor is located in the space bounded by the back surface of the cornea, the front and back of the iris, the front of the lens capsule.

JCH MD

[Tom215]

Thank you so much for your help. Actually my Intraocular Pressure is a little higher than average and my doctor- he is specialist of glaucoma- advise me to apply eye lotion to prevent from glaucoma, but recently I've have some doubts about his way because there seem not to be found a cause of glaucoma definitely. I'm thinking that high Intraocular Pressure is not a cause of glaucoma if it's not very high. The total size of eye ball is larger than that of cornea and if the aqueous humour is filled within eyeball or filled around the cornea, pressure on the retina and the optic nerve is lower than measured Intraocular Pressure because pressure is dependent on the surface area. I estimate the ratio is a 15:1 roughly; but I don't know how accurate is this estimation because I'm not a specialist. And from the result, real pressure that means pressure on the retina and optic nerve is about 1/15 of measured Intraocular Pressure. In case of Primary Open Angle Glaucoma, It was quite effective if Intraocular Pressure drop about 30%. I heard that 90% of Primary Open Angle Glaucoma is NTG and Let us suppose their average Intraocular Pressure is 17mmHg. And let us suppose one a man who is NTG and he succeed to drop about 30%. Now by using my estimation, the 30% is 0.34mmHg(17mmHg×30%×1/15 = 0.34mmHg) as the pressure on the  retina and optic nerve. 0.34mmHg is about 0.4g/cm. Actually is this adequately for him? Why can a little
pressure effective on NTG? So this is actually I'd like to ask my doctor today..

[Tom215]

Sorry Dr, my previous comment has many mistake and I'm good at English. I rewrite previous one.

Thank you so much for your help. Actually my Intraocular Pressure is a little higher than average and my doctor- he is specialist of glaucoma- advise me to apply eye lotion to prevent from glaucoma, but recently I've have some doubts about his way because there seem not to be found a cause of glaucoma definitely. I'm thinking that high Intraocular Pressure is not a cause of glaucoma if it's not very high. The total size of eye ball is larger than that of cornea and if the aqueous humour isn't filled within eyeball or filled around the cornea, pressure on the retina and the optic nerve is lower than measured Intraocular Pressure because pressure is dependent on the surface area. I estimate the ratio is a 15:1 roughly; but I don't know how accurate is this estimation because I'm not a specialist. And from the result, real pressure that means pressure on the retina and optic nerve is about 1/15 of measured Intraocular Pressure. In case of Primary Open Angle Glaucoma, It was quite effective if Intraocular Pressure drop about 30%. I heard that 90% of Primary Open Angle Glaucoma is NTG and Let us suppose their average Intraocular Pressure is 17mmHg. And let us suppose a man who has NTG and he succeed to drop about 30%. Now by using my estimation, the 30% is 0.34mmHg (17mmHg×30%×1/15 = 0.34mmHg) as the pressure on the  retina and optic nerve. 0.34mmHg is about 0.4g/cm. Actually is this adequately for him? Why can a little
pressure effective on NTG? So this is actually I'd like to ask my doctor today..

[John C Hagan III, MD, FACS, FAAO]

There are many types of glaucoma. Normal tension glaucoma is not 90% of POAG. Your calculations about the IOP at the optic nerve are in error. Also bear in mind that the IOP changes from hour to hour like the tide. Perhaps as many as 40% of POAG patients have normal IOP during "office" hours but run high IOP in evening or night.

Your best bet is to find a good glaucoma specialist and follow their advise.

A great unknown in glaucoma is why one person has severe damage with an average IOP of 19 and another tolerates a IOP of 30 for decades without out damage.

There is much much we don't know about glaucoma.

JCH MD

[Tom215]

I thank you so much. I'm Japanese and I'm not good at English. I excuse my bad English.

[John C Hagan III, MD, FACS, FAAO]

Certainly better than my Japanese. One of our favorite trips was to Japan.

JCH MD