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Transvitreal Radiofrequency Diathermy
AMERICAN JOURNAL OF OPHTHALMOLOGY
282
FEBRUARY, 1977
BOOK REVIEWS
REFERENCES
1. Abramson, D. H., Chang, S., and Coleman, D. J.: Pilocarpine therapy in glaucoma. Arch. Ophthalmol. 94:914, 1976. 2. Lebensohn, J. E.: Minus lenses as an effective adjuvant in control of juvenile glaucoma, Am. J. Ophthalmol. 35:1029, 1952.
Introduction to Ophthalmology. B y J o h n Parr. Dunedin, New Zealand, University of Otoga Press, J o h n M c l n d o e Ltd., 1976. Paperbound, 2 1 6 pages, preface, table of contents, index, 2 3 9 black and white figures. $ 1 4 .
Transvitreal Radiofrequency Diathermy Editor: Sometime ago I recommended a straight insulated probe for use of transvitreal diathermy of retina and retinal vess e l s . This probe is used with the radiofrequency (13 M H z ) diathermy unit of Medical Instrument Research Associates (MIRA). Recently, I have heard of two cases in which the probe was used to coagulate bleeding vessels in the vicinity of the optic nerve head during vitrectomy. In both cases the eyes ended up with no light perception. Possibly the stray radiofrequency current, intended to coagulate protruding tissue, reached the optic nerve and actually coagulated nerve tissue. Although this possibility is not proven, I feel that coagulation of tissue in close vicinity o f the optic nerve by radiofrequency diathermy with a simple insulated probe cannot be recommended anymore. T h e manufacturer has been informed of the potential hazard and has agreed to discontinue the sale of this probe. 1 - 3
R O B E R T M A C H E M E R , M.D.
Miami,
Florida
REFERENCES
1. Parel, J.-M., Machemer, R., and Aumayr, W.: A new concept for vitreous surgery. 4. Improvements in instrumentation and illumination. Am. J. Ophthalmol. 77:6, 1974. 2. Machemer, R.: A new concept for vitreous surgery. 7. Two instrument techniques in pars plana vitrectomy. Arch. Ophthalmol. 92:407, 1974. 3. Machemer, R.: Vitrectomy, A Pars Plana Approach. New York, Grune & Stratton, 1975.
Professor Parr has developed a book for medical students. His goal is to provide sufficient information at a reasonable level of ophthalmological competence required for medical practitioners who are not ophthalmologists. T h e book is organized into four parts: Basic Sciences; E x amination and Interpretation; Clinical Topics; and Casualty Officer Ophthalmology. T h e first part, Basic Sciences, is a particularly lucid explanation of the anatomy, optics and physiology of the eye, and the visual system. T h e illustrations are clear and helpful. It may be more than the average medical student will want to know or be able to learn about ophthalmology. It is an unusually clear exposition for the medical student who is especially interested in ophthalmology. I think it would be particularly appropriate for the student rotating on a clinical elective in ophthalmology with a special interest in the area. T h e second part, Examination and Interpretation, provides a description of the ocular systems and an explanation o f the various examination procedures. While it may not allow the student to approach the patient directly and his visual complaints after reading this chapter, it would be most helpful. T h e fundus diagrams clarify the correlation o f the ophthalmoscopic and structural characteristics of the fundus. Understandably, color photographs or simulations have not been included. T h e section on clinical conditions pro-
282
FEBRUARY, 1977
BOOK REVIEWS
REFERENCES
1. Abramson, D. H., Chang, S., and Coleman, D. J.: Pilocarpine therapy in glaucoma. Arch. Ophthalmol. 94:914, 1976. 2. Lebensohn, J. E.: Minus lenses as an effective adjuvant in control of juvenile glaucoma, Am. J. Ophthalmol. 35:1029, 1952.
Introduction to Ophthalmology. B y J o h n Parr. Dunedin, New Zealand, University of Otoga Press, J o h n M c l n d o e Ltd., 1976. Paperbound, 2 1 6 pages, preface, table of contents, index, 2 3 9 black and white figures. $ 1 4 .
Transvitreal Radiofrequency Diathermy Editor: Sometime ago I recommended a straight insulated probe for use of transvitreal diathermy of retina and retinal vess e l s . This probe is used with the radiofrequency (13 M H z ) diathermy unit of Medical Instrument Research Associates (MIRA). Recently, I have heard of two cases in which the probe was used to coagulate bleeding vessels in the vicinity of the optic nerve head during vitrectomy. In both cases the eyes ended up with no light perception. Possibly the stray radiofrequency current, intended to coagulate protruding tissue, reached the optic nerve and actually coagulated nerve tissue. Although this possibility is not proven, I feel that coagulation of tissue in close vicinity o f the optic nerve by radiofrequency diathermy with a simple insulated probe cannot be recommended anymore. T h e manufacturer has been informed of the potential hazard and has agreed to discontinue the sale of this probe. 1 - 3
R O B E R T M A C H E M E R , M.D.
Miami,
Florida
REFERENCES
1. Parel, J.-M., Machemer, R., and Aumayr, W.: A new concept for vitreous surgery. 4. Improvements in instrumentation and illumination. Am. J. Ophthalmol. 77:6, 1974. 2. Machemer, R.: A new concept for vitreous surgery. 7. Two instrument techniques in pars plana vitrectomy. Arch. Ophthalmol. 92:407, 1974. 3. Machemer, R.: Vitrectomy, A Pars Plana Approach. New York, Grune & Stratton, 1975.
Professor Parr has developed a book for medical students. His goal is to provide sufficient information at a reasonable level of ophthalmological competence required for medical practitioners who are not ophthalmologists. T h e book is organized into four parts: Basic Sciences; E x amination and Interpretation; Clinical Topics; and Casualty Officer Ophthalmology. T h e first part, Basic Sciences, is a particularly lucid explanation of the anatomy, optics and physiology of the eye, and the visual system. T h e illustrations are clear and helpful. It may be more than the average medical student will want to know or be able to learn about ophthalmology. It is an unusually clear exposition for the medical student who is especially interested in ophthalmology. I think it would be particularly appropriate for the student rotating on a clinical elective in ophthalmology with a special interest in the area. T h e second part, Examination and Interpretation, provides a description of the ocular systems and an explanation o f the various examination procedures. While it may not allow the student to approach the patient directly and his visual complaints after reading this chapter, it would be most helpful. T h e fundus diagrams clarify the correlation o f the ophthalmoscopic and structural characteristics of the fundus. Understandably, color photographs or simulations have not been included. T h e section on clinical conditions pro-