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Echocardiographic diagnosis of congenital heart disease
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Book Reviews P H Y S I C A L M E C H A N I S M S FOR B I O L O G I C A L E F F E C T S O F U L T R A S O U N D By W. L. NYBORG.DHEW Publication (FDA) 78-8062, 59 pp., available without charge from BRH Technical Information Staff (HFX-25), 5600 Fishers Lane, Rockville, MD 20857 (Limited distribution).
This valuable publication comprises the text of four lectures delivered by Prof. Nyborg at the Bureau of Radiological Health, FDA, Rockville, MD during the spring 1976. The accurate abstract reads:
tion torque (time-averaged torque on a small body, which may cause it to twist or spin) and acoustic microstreaming (time-averaged circulations set up in fluid-filled spaces). Viscous stresses associated with acoustic microstreaming are especially important near microscopic gaseous bodies; it is im"In this report, available information is re- portant to know whether these exist in mammalian viewed on the principles or mechanisms, as they systems. are often called, by which ultrasound produces The report also contains a brief summary of changes in living systems. In the science of biolo- available data for effects of ultrasound on maregical ultrasound, as in any other science, a know- marian tissues. In particular the lowest intensity ledge of principles is valuable in that it enhances levels at which significant effects have been our ability to make predictions. It is natural to reported are compared w/th levels generated by stress physical mechanisms because ultrasound is equipment presently being used in diagnostic a physical agent. The mechanism best understood medical practice. Attempts to explain these is that of sonically generated heat. Temperature b/oe~ects data in terms of principles reveal the elevations can lead to sipiflcaat alterations in inadequacy of our understanding at this time. rates of biochemical reactions, to structural Continued and inteus/fled research on mechanisms breakdown of macromolecules and membranes, is obviously needed, especially for viscoelastic and and to abnormalities in developing orlunisms, inlmmogeueous media sim/lar to tissues. Until Many experiments have been done in which these mechanisms are known we cannot ultrasound is applied to aqueous suspensions of confidently extrapolate to cfinical situations the macromolncules or cells; in these, enzymes m y results obtained from laboratory experiments." be inactivated or cells modified in structure and/or The publication of these lectures by one of the function. Here (when temperature elevation is most eminent, cautious and trustworthy scientists avoided) the mechanism is usually sonic cavita- engnged in biophysical research on the effects of tion, an activity of small bodies comprised of gas ultrasound is a timely and essential service to the scientific community and the public in general. or vapor. When ultrasound produces bineffects under. This report can be unequivocably recommended cond/tions where temperature elevation is ruled to all readers of tbiq journal out the mechanism can sometimes be identified as P~TF~ 13. EDMONDS one associated with time-avemj~ souicaliy 5R/Internat/ona/ generated stresses. Among mechanisms in this Menlo Park, class are the phenomena of radiation force (time- California 94025, averaged force on a particle or structure), radia- U.S.A.
ECHOCARDIOGRAPHIC DIAGNOSIS OF CONGENITAL HEART •DISEASE By RonERTA G. WILLIAMS and CHARL~ R. TUCKER. Little Brown and Company, Boston, 1978. 352 pp. 115 tip. U.S. $19.95. This book has recently joined the ranks of other fine texts on Pediatric Echocard/ngraphy. It draws upon at least five years of experience by the authors. The major goal of this book is not to provide a comprehensive text on the subject of pediatric echocardingraphy and thus omits chapters on the physical princ/ples of diagnostic ultrasound, suprasternal notch, and contrast
echecardiosmphy. Rather, the goals of the book are to provide: fam/lian'ty with the diagnostic alpplications, an understanding of the role and reliabil/ty of echocardiosraphy in the clinical situnfion, and finally, assessment of the pitfalls of the technique. Hence, the authors have attempted to provide a quick reference atlas which can be used to sup-
Book Reviews plement more complete texts on pediatric echocardiography. To this end, I think the authors have achieved their goals. The book has been divided into four parts: a very brief Introduction, Normal Echocardiographic Anatomy, Echocardiographic Diagnosis in Acyanotic Heart Disease, and finally, Echocardiographic Diagnosis in Cyanotic Heart Disease. Each chapter has conveniently been presented in an outline form under the following headings: anatomy, examination technique, diagnostic features, pitfalls, and differential diagnosis. This will enable readers to find very quickly specific information about particular defects or lesions. In addition, the authors provide pertinent references for each of the points they. wish to make. Numerous tables of normal values likewise are referenced. This approach has provided a ready reference book on a complex subject matter. The somewhat arbitrary separation of subjects that normally inter-relate has, as the authors stated, not interfered with the design of the book or its usefulness. At times, the anatomic descriptions are quite detailed and may be difficult for individuals without a substantial background in congenital heart disease to follow the descriptive text. This problem could have been avoided by including more appropriate illustrations regarding the ana-
415
tomy. In many instances, the echoes though accurate and representative of the disease discussed, are very small and difficult to see. It would certainly have helped if the echoes could have been expanded into much of the unused portions of the pages. Often, there was little referral of the illustrations and echocardiograms in the text to the figures used to illustrate material. This made reading of the text more difficult. There were many instances in which additional illustrations and echoes would have enhanced the echographic and anatomic points that the authors wished to emphasize. This is particularly true for the pitfalls. Finally, it was somewhat disappointing that the authors failed to emphasize the clinical utility of echocardiographic systolic time intervals in assessing pulmonary vascular resistance. All in all, I think this text provides a useful adjunct to current literature on Pediatric Echocardiography and would certainly be a welcome addition to the library of most pediatricians and other physicians interested in pediatric echocardiography. R. A. MEYER Childrens' Hospital Medical Center Cincinnati Ohio U.S.A.
Book Reviews P H Y S I C A L M E C H A N I S M S FOR B I O L O G I C A L E F F E C T S O F U L T R A S O U N D By W. L. NYBORG.DHEW Publication (FDA) 78-8062, 59 pp., available without charge from BRH Technical Information Staff (HFX-25), 5600 Fishers Lane, Rockville, MD 20857 (Limited distribution).
This valuable publication comprises the text of four lectures delivered by Prof. Nyborg at the Bureau of Radiological Health, FDA, Rockville, MD during the spring 1976. The accurate abstract reads:
tion torque (time-averaged torque on a small body, which may cause it to twist or spin) and acoustic microstreaming (time-averaged circulations set up in fluid-filled spaces). Viscous stresses associated with acoustic microstreaming are especially important near microscopic gaseous bodies; it is im"In this report, available information is re- portant to know whether these exist in mammalian viewed on the principles or mechanisms, as they systems. are often called, by which ultrasound produces The report also contains a brief summary of changes in living systems. In the science of biolo- available data for effects of ultrasound on maregical ultrasound, as in any other science, a know- marian tissues. In particular the lowest intensity ledge of principles is valuable in that it enhances levels at which significant effects have been our ability to make predictions. It is natural to reported are compared w/th levels generated by stress physical mechanisms because ultrasound is equipment presently being used in diagnostic a physical agent. The mechanism best understood medical practice. Attempts to explain these is that of sonically generated heat. Temperature b/oe~ects data in terms of principles reveal the elevations can lead to sipiflcaat alterations in inadequacy of our understanding at this time. rates of biochemical reactions, to structural Continued and inteus/fled research on mechanisms breakdown of macromolecules and membranes, is obviously needed, especially for viscoelastic and and to abnormalities in developing orlunisms, inlmmogeueous media sim/lar to tissues. Until Many experiments have been done in which these mechanisms are known we cannot ultrasound is applied to aqueous suspensions of confidently extrapolate to cfinical situations the macromolncules or cells; in these, enzymes m y results obtained from laboratory experiments." be inactivated or cells modified in structure and/or The publication of these lectures by one of the function. Here (when temperature elevation is most eminent, cautious and trustworthy scientists avoided) the mechanism is usually sonic cavita- engnged in biophysical research on the effects of tion, an activity of small bodies comprised of gas ultrasound is a timely and essential service to the scientific community and the public in general. or vapor. When ultrasound produces bineffects under. This report can be unequivocably recommended cond/tions where temperature elevation is ruled to all readers of tbiq journal out the mechanism can sometimes be identified as P~TF~ 13. EDMONDS one associated with time-avemj~ souicaliy 5R/Internat/ona/ generated stresses. Among mechanisms in this Menlo Park, class are the phenomena of radiation force (time- California 94025, averaged force on a particle or structure), radia- U.S.A.
ECHOCARDIOGRAPHIC DIAGNOSIS OF CONGENITAL HEART •DISEASE By RonERTA G. WILLIAMS and CHARL~ R. TUCKER. Little Brown and Company, Boston, 1978. 352 pp. 115 tip. U.S. $19.95. This book has recently joined the ranks of other fine texts on Pediatric Echocard/ngraphy. It draws upon at least five years of experience by the authors. The major goal of this book is not to provide a comprehensive text on the subject of pediatric echocardingraphy and thus omits chapters on the physical princ/ples of diagnostic ultrasound, suprasternal notch, and contrast
echecardiosmphy. Rather, the goals of the book are to provide: fam/lian'ty with the diagnostic alpplications, an understanding of the role and reliabil/ty of echocardiosraphy in the clinical situnfion, and finally, assessment of the pitfalls of the technique. Hence, the authors have attempted to provide a quick reference atlas which can be used to sup-
Book Reviews plement more complete texts on pediatric echocardiography. To this end, I think the authors have achieved their goals. The book has been divided into four parts: a very brief Introduction, Normal Echocardiographic Anatomy, Echocardiographic Diagnosis in Acyanotic Heart Disease, and finally, Echocardiographic Diagnosis in Cyanotic Heart Disease. Each chapter has conveniently been presented in an outline form under the following headings: anatomy, examination technique, diagnostic features, pitfalls, and differential diagnosis. This will enable readers to find very quickly specific information about particular defects or lesions. In addition, the authors provide pertinent references for each of the points they. wish to make. Numerous tables of normal values likewise are referenced. This approach has provided a ready reference book on a complex subject matter. The somewhat arbitrary separation of subjects that normally inter-relate has, as the authors stated, not interfered with the design of the book or its usefulness. At times, the anatomic descriptions are quite detailed and may be difficult for individuals without a substantial background in congenital heart disease to follow the descriptive text. This problem could have been avoided by including more appropriate illustrations regarding the ana-
415
tomy. In many instances, the echoes though accurate and representative of the disease discussed, are very small and difficult to see. It would certainly have helped if the echoes could have been expanded into much of the unused portions of the pages. Often, there was little referral of the illustrations and echocardiograms in the text to the figures used to illustrate material. This made reading of the text more difficult. There were many instances in which additional illustrations and echoes would have enhanced the echographic and anatomic points that the authors wished to emphasize. This is particularly true for the pitfalls. Finally, it was somewhat disappointing that the authors failed to emphasize the clinical utility of echocardiographic systolic time intervals in assessing pulmonary vascular resistance. All in all, I think this text provides a useful adjunct to current literature on Pediatric Echocardiography and would certainly be a welcome addition to the library of most pediatricians and other physicians interested in pediatric echocardiography. R. A. MEYER Childrens' Hospital Medical Center Cincinnati Ohio U.S.A.