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Fleck Retina in Kjellin's Syndrome
618
May, 1985
AMERICAN JOURNAL OF OPHTHALMOLOGY
lar pressure with a dependent posture is probably associated with increases in episcleral venous pressure." They then quoted Goldmann's equation, "intraocular pressure equals (FIe) + Pev where F is the rate of aqueous production, C is the facility of outflow, and Pev is the episcleral venous pressure." This formula, however, only holds true in a steady state at a particular intraocular pressure. 1 As the authors themselves found, "the increase in intraocular pressure upon inversion occurs almost immediately." In the inverted position the steady state of the eye is disturbed, and the intraocular volume changes, capacitance, and resistance are the most important factors in determining the intraocular pressure. Between 10 and 40 mm Hg, the capacitance of the eye is approximately 1. 1 This means that for every microliter of change in intraocular volume, the intraocular pressure increases approximately 1 mm Hg. Therefore, even if the episcleral venous pressure were increased to a level at which aqueous outflow was completely halted, the intraocular pressure could only increase on the order of 2 mm Hg/min given an aqueous inflow rate of 2 ul/min. One would expect that the increase in intraocular pressure from this mechanism would be slow and gradual. Theoretically, if the episcleral venous pressure were increased above the original intraocular pressure, there could be a reversal of flow from episcleral veins into the eye, but this probably would also be slow. It seems to us that the most likely explanation for the immediate increase in intraocular pressure with inversion is either pressure on the globe from increased orbital contents or an increase in intraocular volume. A rapid change in the choroidal volume of only 20 ~l could cause the intraocular pressure to increase 20 mm Hg immediately. As the episcleral venous pie xis is engorged in the dependent position, so, no doubt, is the choroidal vasculature. This is important, as there are many factors that can affect choroidal volume and can, therefore, have immediate and devastating effects on the intraocular pressure or intraocular volume relationships, hypoventilation during anesthesia being one of the most significant of these. We believe that the observations of Weinreb, Cook, and Friberg and others that intraocular pressure can increase in the head-dependent position is important in that it draws attention to the choroid as a potential mediator of intraocular pressure. THOMAS J. SMITH, M.D. JOHN LEWIS, M.D.
Lexington, Kentucky
Reference I. Moses, R. A.: Intraocular pressure. In Moses, R. A. (ed.): Adler's Physiology of the Eye. St.Louis, C. V. Mosby, 1981, pp. 230 and 241.
_ _ _ _ _ _ _ Reply
_
EDITOR:
As we stated in our article, we believe that "in addition to increased episcleral venous pressure, compressive forces placed upon the globe by congested orbital contents and an increase in the ocular blood volume with congestion of the uvea may also contribute to the increase in intraocular pressure." During inversion, it is likely that increased orbital tissue pressure alters the "capacitance of the eye. " We thank Drs. Smith and Lewis for their comments. ROBERT N. WEINREB, M.D.
San Diego, California THOMAS H. FRIBERG, M.D.
Dallas, Texas
Fleck Retina in
Kjellin's
Syndrome
EDITOR:
I read with interest the article, "Fleck retina in Kjellin's syndrome" (Am. J. Ophthalmol. 99:45, Jan. 1985) by S. G. Farmer, W. T. Longstreth, Jr., R. P. Kalina, and A. B. Todorov, in which the fundus findings were believed to represent a "fifth" type of the fleck retina syndrome and which may be specific for the Kjellin's syndrome. Although the findings were compared to fundus flavimaculatus, no mention was made of the pattern dystrophies of the retinal pigment epithelium. One type of pattern dystrophy reported by Gass.! originally called peculiar foveomacular dystrophy, demonstrated a yellow lesion at the level of the retinal pigment epithelium, usually in the center of the macula. On angiography, the lesion blocked fluorescence centrally and had an irregular ring of transmitted fluorescence from the choroid. At the Bascom Palmer Eye Institute, several cases have been seen with multiple lesions indistinguishable from the cases of Farmer and associates. Interest-
Vol. 99, No.5
619
Correspondence
ingly, none of our patients had neurologic disease and, with time, the fundus pattern often progressed to show a typical butterfly or reticular pattern. The visual acuity usually remains good (20/20 to 20/40). Subretinal neovascularization occasionally occurs with the pattern dystrophies. As the pattern dystrophies are fairly common, perhaps the association with the Kjellin's syndrome is coincidental. Regardless, it is important to recognize that the fundus findings reported with Kjellin's syndrome may represent a pattern dystrophy of the retinal pigment epithelium. SCOTT E. PAUTLER, M.D.
Miami, Florida
Reference 1. Gass, J. D. M.: A clinicopathologic study of a peculiar foveomacular dystrophy. Trans. Am. Ophthalmol. Soc. 72;139, 1974.
with retinal flecks. Perhaps the similarities of the retinal lesions in these disorders simply reflect the limited ways in which the retinal pigment epithelium responds to diverse metabolic insults. SAMUEL G. FARMER, M.D.
Iowa City, Iowa
References 1. Gass, J. D. M.: A clinical pathologic study of a peculiar foveomacular dystrophy. Trans. Am. Ophthalmol. Soc. 72:139, 1974. 2. Watzke, R. C., Folk, J. c.. and Lang, R. M.: Pattern dystrophy of the retinal pigment epithelium. Ophthalmology 89:1400, 1982. 3. Hsieh, R. C.; Fine, B.S., and Lyons, J. 5.: Patterned dystrophies of the retinal pigment epithelium. Arch. Ophthalmol. 95:428. 1977.
Floppy Eyelid With Hyperglyclnemla _ _ _ _ _ _ _ Reply
_
EDITOR:
Dr. Pautler points out that the differential diagnosis of fundus disorders with flecks includes pattern dystrophy of the retinal pigment epithelium. We did not include this disorder in our discussion of the ocular findings in Kjellin's syndrome and we appreciate Dr. Pautler's recognition of this omission. In addition to the cases reported by Cass,' Watzke, Folk, and Lang! also described patients with pattern dystrophy whose "dot and halo" lesions are reminiscent of the findings in Kjellin's syndrome. We doubt, however, that the patients we described have pattern dystrophy and a coincidental neurologic disease. Unlike Kjellin's syndrome, pattern dystrophy is usually autosomal dominant in transmission" and the yellowish lesions are usually located beneath the foveola, showing a central pigment spot. 1 The chance occurrence of consistently associated pattern dystrophy and spastic paraplegia in several members of unrelated pedigrees seems to us improbable. Nonetheless, we will watch our patients with Kjellin's syndrome with interest for the evolution of a more typical "pattern" lesion. The deposits in both pattern dystrophy's" and Kjellin's syndrome have been postulated to represent accumulations of pigment epithelial lipofuscin such as those found in other conditions associated
EDITOR:
In their article, "Floppy eyelid with hyperglycinemia" (Am. J. Ophthalmol. 98:614, Nov. 1984), E. W. Gerner and S. M. Hughes described a 31-year-old man with spastic paraparesis, hyperglycinemia, and unilateral floppy eyelid. Although the floppy eyelid syndrome may be inherited as an X-linked condition, as they mentioned in their discussion, there are now two women who have been described with this condition. 1,2 With this type of inheritance I would expect that at least some male siblings would be affected. The finding of hyperglycinemia with floppy eyelid is an interesting one, and one discussed intelligently by Gerner and Hughes. As they mentioned, it would be of value to determine serum and urine amino acid levels in other cases of the floppy eyelid syndrome to find a relationship between a metabolic disorder and floppy eyelids. MIGUEL PACIUC, M.D.
Mexico City, Mexico
References 1. Culbertson, W. W., and Ostler, H. B.: The floppy eyelid syndrome. Am. J. Ophthalmol. 92:568, 1981. 2. Paciuc, M., and Mier, M. E.: A woman with the floppy eyelid syndrome. Am. J. Ophthalmol. 93:255, 1982.
May, 1985
AMERICAN JOURNAL OF OPHTHALMOLOGY
lar pressure with a dependent posture is probably associated with increases in episcleral venous pressure." They then quoted Goldmann's equation, "intraocular pressure equals (FIe) + Pev where F is the rate of aqueous production, C is the facility of outflow, and Pev is the episcleral venous pressure." This formula, however, only holds true in a steady state at a particular intraocular pressure. 1 As the authors themselves found, "the increase in intraocular pressure upon inversion occurs almost immediately." In the inverted position the steady state of the eye is disturbed, and the intraocular volume changes, capacitance, and resistance are the most important factors in determining the intraocular pressure. Between 10 and 40 mm Hg, the capacitance of the eye is approximately 1. 1 This means that for every microliter of change in intraocular volume, the intraocular pressure increases approximately 1 mm Hg. Therefore, even if the episcleral venous pressure were increased to a level at which aqueous outflow was completely halted, the intraocular pressure could only increase on the order of 2 mm Hg/min given an aqueous inflow rate of 2 ul/min. One would expect that the increase in intraocular pressure from this mechanism would be slow and gradual. Theoretically, if the episcleral venous pressure were increased above the original intraocular pressure, there could be a reversal of flow from episcleral veins into the eye, but this probably would also be slow. It seems to us that the most likely explanation for the immediate increase in intraocular pressure with inversion is either pressure on the globe from increased orbital contents or an increase in intraocular volume. A rapid change in the choroidal volume of only 20 ~l could cause the intraocular pressure to increase 20 mm Hg immediately. As the episcleral venous pie xis is engorged in the dependent position, so, no doubt, is the choroidal vasculature. This is important, as there are many factors that can affect choroidal volume and can, therefore, have immediate and devastating effects on the intraocular pressure or intraocular volume relationships, hypoventilation during anesthesia being one of the most significant of these. We believe that the observations of Weinreb, Cook, and Friberg and others that intraocular pressure can increase in the head-dependent position is important in that it draws attention to the choroid as a potential mediator of intraocular pressure. THOMAS J. SMITH, M.D. JOHN LEWIS, M.D.
Lexington, Kentucky
Reference I. Moses, R. A.: Intraocular pressure. In Moses, R. A. (ed.): Adler's Physiology of the Eye. St.Louis, C. V. Mosby, 1981, pp. 230 and 241.
_ _ _ _ _ _ _ Reply
_
EDITOR:
As we stated in our article, we believe that "in addition to increased episcleral venous pressure, compressive forces placed upon the globe by congested orbital contents and an increase in the ocular blood volume with congestion of the uvea may also contribute to the increase in intraocular pressure." During inversion, it is likely that increased orbital tissue pressure alters the "capacitance of the eye. " We thank Drs. Smith and Lewis for their comments. ROBERT N. WEINREB, M.D.
San Diego, California THOMAS H. FRIBERG, M.D.
Dallas, Texas
Fleck Retina in
Kjellin's
Syndrome
EDITOR:
I read with interest the article, "Fleck retina in Kjellin's syndrome" (Am. J. Ophthalmol. 99:45, Jan. 1985) by S. G. Farmer, W. T. Longstreth, Jr., R. P. Kalina, and A. B. Todorov, in which the fundus findings were believed to represent a "fifth" type of the fleck retina syndrome and which may be specific for the Kjellin's syndrome. Although the findings were compared to fundus flavimaculatus, no mention was made of the pattern dystrophies of the retinal pigment epithelium. One type of pattern dystrophy reported by Gass.! originally called peculiar foveomacular dystrophy, demonstrated a yellow lesion at the level of the retinal pigment epithelium, usually in the center of the macula. On angiography, the lesion blocked fluorescence centrally and had an irregular ring of transmitted fluorescence from the choroid. At the Bascom Palmer Eye Institute, several cases have been seen with multiple lesions indistinguishable from the cases of Farmer and associates. Interest-
Vol. 99, No.5
619
Correspondence
ingly, none of our patients had neurologic disease and, with time, the fundus pattern often progressed to show a typical butterfly or reticular pattern. The visual acuity usually remains good (20/20 to 20/40). Subretinal neovascularization occasionally occurs with the pattern dystrophies. As the pattern dystrophies are fairly common, perhaps the association with the Kjellin's syndrome is coincidental. Regardless, it is important to recognize that the fundus findings reported with Kjellin's syndrome may represent a pattern dystrophy of the retinal pigment epithelium. SCOTT E. PAUTLER, M.D.
Miami, Florida
Reference 1. Gass, J. D. M.: A clinicopathologic study of a peculiar foveomacular dystrophy. Trans. Am. Ophthalmol. Soc. 72;139, 1974.
with retinal flecks. Perhaps the similarities of the retinal lesions in these disorders simply reflect the limited ways in which the retinal pigment epithelium responds to diverse metabolic insults. SAMUEL G. FARMER, M.D.
Iowa City, Iowa
References 1. Gass, J. D. M.: A clinical pathologic study of a peculiar foveomacular dystrophy. Trans. Am. Ophthalmol. Soc. 72:139, 1974. 2. Watzke, R. C., Folk, J. c.. and Lang, R. M.: Pattern dystrophy of the retinal pigment epithelium. Ophthalmology 89:1400, 1982. 3. Hsieh, R. C.; Fine, B.S., and Lyons, J. 5.: Patterned dystrophies of the retinal pigment epithelium. Arch. Ophthalmol. 95:428. 1977.
Floppy Eyelid With Hyperglyclnemla _ _ _ _ _ _ _ Reply
_
EDITOR:
Dr. Pautler points out that the differential diagnosis of fundus disorders with flecks includes pattern dystrophy of the retinal pigment epithelium. We did not include this disorder in our discussion of the ocular findings in Kjellin's syndrome and we appreciate Dr. Pautler's recognition of this omission. In addition to the cases reported by Cass,' Watzke, Folk, and Lang! also described patients with pattern dystrophy whose "dot and halo" lesions are reminiscent of the findings in Kjellin's syndrome. We doubt, however, that the patients we described have pattern dystrophy and a coincidental neurologic disease. Unlike Kjellin's syndrome, pattern dystrophy is usually autosomal dominant in transmission" and the yellowish lesions are usually located beneath the foveola, showing a central pigment spot. 1 The chance occurrence of consistently associated pattern dystrophy and spastic paraplegia in several members of unrelated pedigrees seems to us improbable. Nonetheless, we will watch our patients with Kjellin's syndrome with interest for the evolution of a more typical "pattern" lesion. The deposits in both pattern dystrophy's" and Kjellin's syndrome have been postulated to represent accumulations of pigment epithelial lipofuscin such as those found in other conditions associated
EDITOR:
In their article, "Floppy eyelid with hyperglycinemia" (Am. J. Ophthalmol. 98:614, Nov. 1984), E. W. Gerner and S. M. Hughes described a 31-year-old man with spastic paraparesis, hyperglycinemia, and unilateral floppy eyelid. Although the floppy eyelid syndrome may be inherited as an X-linked condition, as they mentioned in their discussion, there are now two women who have been described with this condition. 1,2 With this type of inheritance I would expect that at least some male siblings would be affected. The finding of hyperglycinemia with floppy eyelid is an interesting one, and one discussed intelligently by Gerner and Hughes. As they mentioned, it would be of value to determine serum and urine amino acid levels in other cases of the floppy eyelid syndrome to find a relationship between a metabolic disorder and floppy eyelids. MIGUEL PACIUC, M.D.
Mexico City, Mexico
References 1. Culbertson, W. W., and Ostler, H. B.: The floppy eyelid syndrome. Am. J. Ophthalmol. 92:568, 1981. 2. Paciuc, M., and Mier, M. E.: A woman with the floppy eyelid syndrome. Am. J. Ophthalmol. 93:255, 1982.