why optical coherence tomography vs. fluorescein angiogram?

---

Request for Question Clarification by pafalafa-ga on 25 Feb 2004 08:50 PST

Although there are many detailed descriptions available of the two
techniques you mentioned, there appear to be only three professional,
medical studies available that directly compare and contrast OCT and
FA.

OCT seems to have a slight edge in identifying and quantifying certain
conditions of the eye.

Would you like me to summarize the few available studies as an answer
to your question?

---

Clarification of Question by pru-ga on 27 Feb 2004 09:49 PST

I need actual articles so I can show an insurance company why they
should cover Optical Coherence Tomography (OCT).  Fluorescein
angiography has been the gold standard--OCT is the newer kid on the
block.

---

Request for Question Clarification by pafalafa-ga on 27 Feb 2004 09:54 PST

pru-ga,

Unfortunately, we cannot post full articles here due to copyright restrictions.  

However, I can certainly give you:

--full citations for the articles

--article summaries

--a link to an on-line abstract

and I can also let you know if the full article itself is available
on-line (they sometimes are, usually for a fee).

Your doctor, or a librarian, should be able to get full copies of the
articles for you.

Would that sort of information work as an answer to your question?

---

Clarification of Question by pru-ga on 25 Mar 2004 07:34 PST

Just today I found the last communication you sent me!  I've been
checking every day, but obviously didn't know where to look.  Yes,the
information you mentioned in that note would answer my question. 
Thank you for providing it.

Hello again, pru-ga,

I'm glad you were able to find -- and reply to -- my earlier comment. 
Google Answers is a great service, but it can be a bit tricky at
times, especially for first-time users.

As I had mentioned, I found three studies that directly relate to your question.  

I found these by searching the very useful, very comprehensive medical
database known as PubMed, which is maintained by the federal National
Institutes of Health in the U.S.

The main PubMed search page can be found at:

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi

where I conducted a search on the terms:

"optical coherence tomography" "fluorescein angiogram"

(I also varied the search strategy, looking, e.g. for [ tomography 
angiogram ] but did not find additional relevant studies.)

I excerpted the citations and some text from the three study abstracts
below.  You can view the full abstracts at the links provided with
each citation.

If anything in this answer is not clear -- or if you need additional
information -- just let me know by posting a Request for
Clarification.

Please do not rate this answer until you are satisified that you have
all the information you need.  Let me know how I can help, and I'll be
happy to assist you further.

All the best.

pafalafa-ga


==========


[This study demonstrates the superiority of OCT over FA for detecting
cystoid macular edema]

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12049577

Arch Ophthalmol.  2002 Jun;120(6):731-7.  

Decreased visual acuity associated with cystoid macular edema in neovascular
age-related macular degeneration.

Ting TD, Oh M, Cox TA, Meyer CH, Toth CA.

Department of Ophthalmology, Duke University Medical Center, Box 3802, Erwin
Road, Durham, NC 27710, USA.

OBJECTIVE: To determine the prevalence and visual significance of cystoid
macular edema (CME) in eyes with subfoveal neovascular age-related macular
degeneration using optical coherence tomography (OCT). 

MATERIALS AND METHODS:  The medical records of 61 ... patients...with
nondisciform subfoveal neovascular age-related macular degeneration
were...
reviewed. All patients underwent fluorescein angiography and OCT imaging... 

CONCLUSIONS: ...Cystoid macular edema is more common with horoidal
neovascularization containing classic component. The OCT is a useful
test to detect the presence of CME in these patients since CME may be
difficult to identify on fluorescein angiogram.


==========

[Another study showing OCT successfully identifying CME when FA was not able to]


http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=11193945


Nippon Ganka Gakkai Zasshi.  2000 Dec;104(12):943-59.  

[Macular diseases--application of automated static perimetry and optical
coherence tomography]


Iijima H.

Department of Ophthalmology, Yamanashi Medical University.

The usefulness of automated static perimetry and optical coherence tomography in
the management of macular diseases has been described...


......The highly protrusive nature of the orange-red nodule in eyes with
idiopathic polypoidal choroidal vasculopathy was demonstrated with
dimensional measurementwith OCT...  Parafoveal retinal sensitivity
obtained with automatedstaticperimetry was studied in correlation with
retinal thickness measured usingOCT ineyes with branch retinal vein
occlusion showing macular edema without macularnon-perfusion or
massive retinal hemorrhages.  The increased retinal thickness dueto
macular edema is closely correlated with retinal sensitivity both at
the fovea and in theparafoveal area.

...Eighty-nine phakic eyes of 46 patients with retinitis pigmentosa patients
were studied to detect cystoid macular edema using OCT. Cystoid lesions were
observed in the macula in 12 eyes in 6 (13%) of 46 patients. Some eyes with
OCT-proven cystoid macular edema did not show dye pooling in the fluorescein
angiogram...



==========


[And here's the third study, also involving CME, and the detection
benefits of OCT over FA]

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10458174


Am J Ophthalmol.  1999 Aug;128(2):185-91.  

Optical coherence tomography of cystoid macular edema associated with retinitis
pigmentosa.

Hirakawa H, Iijima H, Gohdo T, Tsukahara S.

Department of Ophthalmology, Yamanashi Medical University, Tamaho, Japan.

PURPOSE: To detect cystoid macular edema in consecutive eyes with retinitis
pigmentosa by means of optical coherence tomography and to study the correlation
between cross-sectional structures and angiographic findings in cystoid macular
edema. 

METHODS: In a prospective study, cross-sectional images through the fovea
were evaluated by means of optical coherence tomography...Eyes showing
cystoid appearance in the macula in the optical coherence tomographic
images were further studied with measurement of the dimensions of
cystoid lesions and with a fluorescein angiogram...


CONCLUSION: Cystoid macular edema in eyes with retinitis pigmentosa
could easily be detected with the use of optical coherence tomography
independent of the angiographic degree of dye leakage. The size of
cystoid lesions demonstrated in the optical coherence tomographic
images...was not necessarily correlated with the angiographic grading
of dye leakage....

==========

Again, if you have any questions about accessing the full abstracts,
just let me know.