702 CORRESPONDENCE

of experience under laboratory conditions with isolated time-amplitude ultrasonogra­phy, this method was abandoned in favor of the Β scan and PPI presentation subse­quently employed by us because of the ob­jections detailed in a paper entitled, " A critique of time-amplitude ultrasonography."

For example, Wild, Howry, Ian Donald, Purnell, and others have had similar experi­ences and abandoned isolated time-ampli­tude ultrasonography because of similar ob­jections. Some neuroradiologists who have employed time-amplitude ultrasonography for midline localization in the brain are cur­rently investigating intensity-modulated dis­plays using Β scans ( D e Vlieger in Holland and Chase in the United States).

Because an intensity-modulated system of ultrasonography may be standardized, it is possible to evolve a quantitative system upon which a system of differential diagnosis based upon the acoustic analogues of optical differential criteria may be established.

I think that Dr. Oksala is to be compli­mented for the time and patience required to perfect the technique and the point it has achieved in his hands. However, for general application and for ultimate standardization of ultrasonography, the isolated time-ampli­tude presentation has so many drawbacks that I feel that I must again speak out against its general adoption.

On the basis of the experience with both ultrasonic techniques, it is my contention and the contention of other workers in this field, that a Β scan presentation is more suitable for general application and permits universal standardization which cannot be achieved with isolated time-amplitude ultra­sonography.

(Signed) Gilbert Baum, Bronx, New York .

COMPLICATION DUE TO SILICONE BAND

Editor,

American Journal of Ophthalmology:

The article dealing with a cataract com­plication due to a silicone band in the April, 1 9 6 4 , issue of T H E JOURNAL suggests sev­eral points for discussion.

The preoperative intraocular pressure is recorded as 12 mm. H g (Schiøtz) in each

eye, but no mention is made of the tension

after Van Lint akinesia and retrobulbar in­

jection.

Secondly, the authors mention that "a high

buckle was noted extending from 11:30 to

2 o'clock." In order to avoid high buckles,

which are frequently due to excessive tight­

ening of the encircling silicone band, we

have elected to restore the tension to nor­

mal levels after drainage of subretinal fluid

by closing the scleral flaps over the silicone

plate and, when necessary, injecting saline

into the vitreous cavity. A t the completion

of surgery great care is taken to assure that

the band conforms snugly to a great circle

of the eye without constricting the globe.

Thus, the band helps to perpetuate the

buckle, but does not itself influence ocular

tension. This procedure is in contrast to the

eye-bank eye described by the authors in

which the band was "tightened until the

pressure was 17 mm. Hg" . Although the

ocular tension was normal, the band still

was on a stretch and was influencing pres­

sure in the eye. This is an important point

which demonstrates that normal tensions do

not rule out a taut band. Many detachment

eyes remain hypotensive even after reat­

tachment, so that a pressure of even 15 mm.

H g (Schij^tz) might represent a relative

hypertension due to an encircling band.

Therefore, the height of the buckle becomes

an important clinical sign of a band that

might cause trouble.

W e have seen two cases of cataract ex­

traction with an encircling band in which

these measures were followed and no com­

plications resulted. It is our feeling that,

BOOK R E V I E W S 703

when cataract extraction is contemplated in patients with high buckles, a band under tension should be suspected and in such cases cutting the band may be indicated if the retina is not detached anterior to the buckle. The use o f Diamox and other hypo­tensive agents preoperatively may also help. If, however, the band is not secured under tension during retina surgery complicated cataract extraction hopefully can be avoided.

It would be interesting to hear the past and future experiences of others with this situation before reaching definite conclu­sions.

(Signed) William Tassman, Philadelphia, Pennsylvania.

B O O K R E V I E W S MODERN OPHTHALMOLOGY . Edited by A r ­

nold Sorsby. London, Butterworth, 1 9 6 4 , volumes 1 and 2 . The projected volumes 3 and 4 are scheduled to appear soon. Price: Volume 1, $ 2 6 . 0 0 ; volume 2 , $ 3 0 . 0 0 ; volumes 3 and 4 , $ 5 0 . 0 0 together;

the set of four volumes, $ % . 0 0 . Arnold Sorsby is research professor in

ophthalmology, Royal College of Surgeons and the Royal Eye Hospital. He is also senior surgeon there. His previous contri­butions include his three well-admired series of Modern Trends in Ophthalmology that appeared in 1 9 4 0 , 1 9 4 7 and 1 9 5 5 , in which he revealed his considerable editorial skill.

Volume 1 of Modern Ophthalmology deals with the basic aspects of ophthalmology. Its chapters include expositions of the history of ophthalmology, anatomy, physiology, oph­thalmic optics, pharmacology, methods of examination and the etiology of eye diseases. Prof. Sorsby himself has contributed two chapters and parts of two others. Other contributors include B. J. Bowden, J. B. Davey, J. M. Enoch, A . J. Friedmann, A . H. Keeney, I. H . Leopold, R. A . Moses, A . Palin, J. H . Prince, H. W . Reading and

R. Warwick. The text and illustrations are very good. There are 5 1 2 pages, 2 7 7 figures and a good index.

Volume 2 concerns the systemic aspects of ophthalmology. The chapters make up six major parts. These are prenatal pathogenic influences; infections and allied disorders; nutritional, metabolic and endocrine disturb­ances; disturbances of the central nervous system; the cardiovascular and hemopoietic systems; and other general disturbances.

The contributors are T . H . Aaron, A . J. Ballantyne, J. G. Bellows, H . L. Birge, T . A . S. Boyd, R. A . Burn, A . J. Cameron, D . G. Cogan, J. H . Doggart, A . J. B. Gold­smith, W . M . Grant, M . J. Hogan, Β. Hughes, J. Igersheimer, L. G. Kiloh, M . Klein, R . D . Lawrence, R . Leishman, S. P. Meadows, I. C. Michaelson, S. Nevin, H . Ridley, E . J. Somerset, L. B. Somerville-Large, A . Sorsby, P. Thygeson, P. D . Trevor-Roper, T . H . Whittington, A . C. W o o d s and J. Yudkin.

There are 6 9 5 pages, 2 7 2 figures in black and white, 2 1 colored plates, references and index.

These two volumes and the promise o f two more to come, assuredly o f high qual­ity, will give us a sort of junior encyclo­pedia o f ophthalmology for use in study and reference. The well-known names of the authors and the proven skill o f the editor are warrant to a good job .

Recommended for school, desk and li­brary.

Derrick Vail.

TRANSACTIONS OF T H E A M E R I C A N O P H ­

THALMOLOGICAL SOCIETY ( 1 9 6 3 ) . T o ­

ronto, University of Toronto Press, 1 9 6 4 volume 6 1 . 7 9 6 pages, profusely illus­trated, index. Price: $ 1 8 . 0 0 . The A . O . S . is the first national eye so­

ciety in America, and the second oldest in the world, having been established just one year after the Heidelberg Ophthalmological