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Universal Slitlamp Attachment*
913
NOTES, CASES, INSTRUMENTS
Fig. 4 (Worst). Scleral window for viewing the fundus of a cataractous eye. (Insert) Scleral but ton.
A trephine incision is made halfway into the sclera of the pars plana, and sutured with the Lindner-Mendosa technique. The circular incision is dissected down to the choroidal coat and thewtrephined "lid" is removed. Preventive measures are taken against choroidal hemorrhage (coagulation, epinephrine, and thromboplastin, see Thorpe 3 ). If the choroid bulges out into the trephined hole, the intraocular pressure is lowered by puncturing the anterior chamber. The choroid at the bottom of the trephined hole is dissected away.
With a special forceps a "perspex" but ton, the dimensions of which are given in the insert of Figure 4, is placed over the hole and pressed into it. The button is shaped like a stud and acts in the same manner. If the scleral window is exactly fitted, no vitreous can be lost. Strong illumination of the pupillary area now provides an astonishingly beautiful view of the interior of the eye. The scleral porthole may be tilted with the forceps so that areas not frequently seen, as the equa tor of the lens and the ciliary body, may be readily visualized. Even in the vitre ous, if it is not too obscured with blood, a foreign body can be recognized. The foreign body is removed with the needle-forceps, as is described in the experi mental Case 2. The scleral lid is sutured with the preset sutures. SUMMARY
In these experimental studies, nonmag netic foreign bodies were made more attain able by the use of the anterior chamber refilling forceps in conjunction with a con tact lens and a scleral window. van Starkenborghstraat
10.
REFERENCES
1. Stallard, H. B.: A nonmagnetic foreign body extractor. Brit. J. Ophth., 34:511, 1950. 2. Dixon, J. M.: Nonmagnetic foreign bodies. Am. J. Ophth., 42:301, 1956. 3. Thorpe, H. E.: Ocular endoscope: An instrument for removal of nonmagnetic foreign bodies. Tr. Am. Acad. Ophth., 1943, p. 422.
UNIVERSAL SLITLAMP ATTACHMENT* F O R PLOTTING U N I L A T E R A L CENTRAL SCOTOMAS GEORGE
F.
HILTON,
LIEUT.
(USA)
Camp Wolters, Texas
The accuracy of a visual field study is only as good as the fixation is steady. With stand* From the Eye Clinic, United States Army Hos pital.
ard central visual acuity and with a reason able degree of attentiveness the results are acceptable, but with markedly reduced cen tral acuity the fixation is too unsteady to yield reliable results. This problem can be overcome in the case of unilateral central .scotoma by the unilateral application of the principle used in the Wheatstone stereo scope. This principle has already been ap plied to the campimeter, the cheiroscope, the amblyoscope, and the haploscope used in stigmatoscopy.
914
NOTES, CASES, INSTRUMENTS
Fig. 3 (Hilton). The attachment positioned for plotting the field of the left eye.
Fig. 1 (Hilton). Attachment in place for plotting the visual field of the left eye. Disregard silvering flaw in mirror.
This note describes a simple home-made attachment for use with the Bausch and Lomb Universal slitlamp, which converts it into a one-arm haploscope to be used with the tangent screen. This attachment can be made by any "week-end mechanic" and is in expensive. Materials will cost less than one dollar.
Fig. 2 (Hilton). The fixation point attached to lamp housing.
This attachment is made of wood, a pocket mirror, and a three diopter convex lens from the trial lens set. Its main features and method of attachment are shown in Fig ure 1. The attachment is held in place by a groove in the b o ^ m surface which fits snugly over the three-eights inch bar of the slitlamp arm. The adjustability of the slitlamp arm will permit the mirror to be posi tioned before the fixing eye. The fixation point, in this case a thumb tack, is attached to the slitlamp housing and is readily viewed in the mirror (fig. 2 ) . The mirror also serves as an occluder for the fix ing eye and therefore only the scotomatous eye has a view of the tangent screen (fig. 3). By adjusting the angle of the mirror about its vertical axis, the visual axis of the scoto matous eye can easily be made to pass through the center of the tangent screen, and compensation can be made for any lateral heterophoria. The patient is instructed to fixate the thumb tack continually. By turn ing the mirror this apparatus can be used for either eye. The optics of this setup are shown in Fig ure 4. The optical path from the fixation point to the fixing eye is 25 cm., providing a stimulus to accommodation of four diopters. But it is necessary to have the eyes accom modated only one diopter because the tan-
91S
NOTES, CASES, INSTRUMENTS
LEGEBD: T tangent screen
100 cm.
S OS
D OD L +3 D lens M mirror F f i x a t i o n object H lamp housing - - v i s u a l axes
&T
" C — 2 0 cm;
*l
Fig. 4 (Hilton). Overhead view: Patient, attachment, and tangent screen.
gent screen is at a distance of one meter. A three-diopter convex lens is, therefore, interposed before the fixing eye and this images the fixation point at one meter and provides the requisite one diopter stimula tion to accommodation. The eye to be studied will be accommodated for the plane of the tangent screen. The +3.0D. lens may be fastened to the front edge of the attachment. In addition to providing the proper stimu lus to accommodation the convex lens also magnifies the fixation object X4. Therefore, a very small fixation point, which will still have a reasonably small subtense after mag nification, would be required in order to de mand precise fixation. A pinhead would be more satisfactory than the thumb tack shown here. This attachment has been used several times with good results. Eye Clinic United States Army Hospital.
S C H E P E N S ' BINOCULAR INDIRECT O P H T H A L M O S C O P E * WILLIAM H.
HAVENER,
M.D.
Columbus, Ohio
The purpose of this paper is to encourage the wider use of the Schepens' ophthalmo scope and to dispel doubt as to its value. It is indeed a remarkable instrument and is far superior to the direct ophthalmoscope in the following respects: 1. PENETRATION
Penetration through hazy media is the characteristic of this ophthalmoscope which will most often prove helpful to the average ophthalmologist. The following examples will commonly be encountered in practice. A. Hemorrhage. Frequently trauma re sults in vitreous hemorrhage sufficiently dense to obscure details as observed by the * From the Department of Ophthalmology, The Ohio State University.
NOTES, CASES, INSTRUMENTS
Fig. 4 (Worst). Scleral window for viewing the fundus of a cataractous eye. (Insert) Scleral but ton.
A trephine incision is made halfway into the sclera of the pars plana, and sutured with the Lindner-Mendosa technique. The circular incision is dissected down to the choroidal coat and thewtrephined "lid" is removed. Preventive measures are taken against choroidal hemorrhage (coagulation, epinephrine, and thromboplastin, see Thorpe 3 ). If the choroid bulges out into the trephined hole, the intraocular pressure is lowered by puncturing the anterior chamber. The choroid at the bottom of the trephined hole is dissected away.
With a special forceps a "perspex" but ton, the dimensions of which are given in the insert of Figure 4, is placed over the hole and pressed into it. The button is shaped like a stud and acts in the same manner. If the scleral window is exactly fitted, no vitreous can be lost. Strong illumination of the pupillary area now provides an astonishingly beautiful view of the interior of the eye. The scleral porthole may be tilted with the forceps so that areas not frequently seen, as the equa tor of the lens and the ciliary body, may be readily visualized. Even in the vitre ous, if it is not too obscured with blood, a foreign body can be recognized. The foreign body is removed with the needle-forceps, as is described in the experi mental Case 2. The scleral lid is sutured with the preset sutures. SUMMARY
In these experimental studies, nonmag netic foreign bodies were made more attain able by the use of the anterior chamber refilling forceps in conjunction with a con tact lens and a scleral window. van Starkenborghstraat
10.
REFERENCES
1. Stallard, H. B.: A nonmagnetic foreign body extractor. Brit. J. Ophth., 34:511, 1950. 2. Dixon, J. M.: Nonmagnetic foreign bodies. Am. J. Ophth., 42:301, 1956. 3. Thorpe, H. E.: Ocular endoscope: An instrument for removal of nonmagnetic foreign bodies. Tr. Am. Acad. Ophth., 1943, p. 422.
UNIVERSAL SLITLAMP ATTACHMENT* F O R PLOTTING U N I L A T E R A L CENTRAL SCOTOMAS GEORGE
F.
HILTON,
LIEUT.
(USA)
Camp Wolters, Texas
The accuracy of a visual field study is only as good as the fixation is steady. With stand* From the Eye Clinic, United States Army Hos pital.
ard central visual acuity and with a reason able degree of attentiveness the results are acceptable, but with markedly reduced cen tral acuity the fixation is too unsteady to yield reliable results. This problem can be overcome in the case of unilateral central .scotoma by the unilateral application of the principle used in the Wheatstone stereo scope. This principle has already been ap plied to the campimeter, the cheiroscope, the amblyoscope, and the haploscope used in stigmatoscopy.
914
NOTES, CASES, INSTRUMENTS
Fig. 3 (Hilton). The attachment positioned for plotting the field of the left eye.
Fig. 1 (Hilton). Attachment in place for plotting the visual field of the left eye. Disregard silvering flaw in mirror.
This note describes a simple home-made attachment for use with the Bausch and Lomb Universal slitlamp, which converts it into a one-arm haploscope to be used with the tangent screen. This attachment can be made by any "week-end mechanic" and is in expensive. Materials will cost less than one dollar.
Fig. 2 (Hilton). The fixation point attached to lamp housing.
This attachment is made of wood, a pocket mirror, and a three diopter convex lens from the trial lens set. Its main features and method of attachment are shown in Fig ure 1. The attachment is held in place by a groove in the b o ^ m surface which fits snugly over the three-eights inch bar of the slitlamp arm. The adjustability of the slitlamp arm will permit the mirror to be posi tioned before the fixing eye. The fixation point, in this case a thumb tack, is attached to the slitlamp housing and is readily viewed in the mirror (fig. 2 ) . The mirror also serves as an occluder for the fix ing eye and therefore only the scotomatous eye has a view of the tangent screen (fig. 3). By adjusting the angle of the mirror about its vertical axis, the visual axis of the scoto matous eye can easily be made to pass through the center of the tangent screen, and compensation can be made for any lateral heterophoria. The patient is instructed to fixate the thumb tack continually. By turn ing the mirror this apparatus can be used for either eye. The optics of this setup are shown in Fig ure 4. The optical path from the fixation point to the fixing eye is 25 cm., providing a stimulus to accommodation of four diopters. But it is necessary to have the eyes accom modated only one diopter because the tan-
91S
NOTES, CASES, INSTRUMENTS
LEGEBD: T tangent screen
100 cm.
S OS
D OD L +3 D lens M mirror F f i x a t i o n object H lamp housing - - v i s u a l axes
&T
" C — 2 0 cm;
*l
Fig. 4 (Hilton). Overhead view: Patient, attachment, and tangent screen.
gent screen is at a distance of one meter. A three-diopter convex lens is, therefore, interposed before the fixing eye and this images the fixation point at one meter and provides the requisite one diopter stimula tion to accommodation. The eye to be studied will be accommodated for the plane of the tangent screen. The +3.0D. lens may be fastened to the front edge of the attachment. In addition to providing the proper stimu lus to accommodation the convex lens also magnifies the fixation object X4. Therefore, a very small fixation point, which will still have a reasonably small subtense after mag nification, would be required in order to de mand precise fixation. A pinhead would be more satisfactory than the thumb tack shown here. This attachment has been used several times with good results. Eye Clinic United States Army Hospital.
S C H E P E N S ' BINOCULAR INDIRECT O P H T H A L M O S C O P E * WILLIAM H.
HAVENER,
M.D.
Columbus, Ohio
The purpose of this paper is to encourage the wider use of the Schepens' ophthalmo scope and to dispel doubt as to its value. It is indeed a remarkable instrument and is far superior to the direct ophthalmoscope in the following respects: 1. PENETRATION
Penetration through hazy media is the characteristic of this ophthalmoscope which will most often prove helpful to the average ophthalmologist. The following examples will commonly be encountered in practice. A. Hemorrhage. Frequently trauma re sults in vitreous hemorrhage sufficiently dense to obscure details as observed by the * From the Department of Ophthalmology, The Ohio State University.