OPTICAL OPHTHALMODYNAMOMETER

• US 3,706,304 A
• Filed: 02/19/1970
• Issued: 12/19/1972
• Est. Priority Date: 02/19/1970
• Status: Expired due to Term

• Current Assignee: Hampson A. Sisler
• Original Assignee: Hampson A. Sisler
• Inventors: Sisler, Hampson A.
• Primary Examiner(s): Howell, Kyle L.
• Application Number:
  US05/012,604
• Time in Patent Office: 1,034 Days
• Field of Search: 128/2T,2R,2.5N,2.5R,2.5P 73/80 351/6
• US Class Current: 600/489
• CPC Class Codes: A61B 3/16 for measuring intraocular pressure, e.g. tonometers
• CPC Class Codes: A61B 5/02216 Ophthalmodynamometers

Abstract

The disclosed ophthalmodynamometer, an instrument for measuring the dynamic opthalmic artery blood pressure, is herein called an optical ophthalmodynamometer because it provides coincident axes of pressure application and visual observation of the characteristic arterial pulsations at measurement of systole and diastole. This instrument is advantageously and readily adapted as an additional attachment for the versatile slit lamp, which is a basic instrument used for eye examination and does not require an assistant for the examiner. The pressure is applied through a fundus lens mounted in a hollow cylindrical member, the axis of which is the axis of observation and through which illumination can be supplied and received paraxially without interferring with the observation. The diameter of the fundus lens is selected to be in the range from about 6 millimeters to about 10 millimeters.

Claims

1. An instrument comprising an optical ophthalmodynamometer including a fundus lens which is at least partially transmissive to light, supporting structure for the lens, the support structure constructed and arranged to allow the passage of illuminating rays along a central portion of the lens when it is placed in the path of illumination, the lens being so constructed along a front face as to allow substantially coincident registry between at least its said central portion and the line-of-sight of an eyeball to be tested, pressure generating means arranged for applying an increasing pressure through said lens to said eyeball, said pressure generating means interconnected to said support structure, there being adjusting means operatively associated with the pressure generating means capable of increasing and decreasing said pressure, there being additional means associated with the instrument arranged to maintain a selected pressure at a relatively lower level for a time sufficient to allow determination of diastole from indicator means, said additional means also arranged to maintain a selected relatively higher pressure a sufficient time to allow determination of systole from said indicator means, there further being indicator means associated with the instrument having indicia indicative of the pressure being applied to the eyeball through the lens whereby said ophthalmodynamometer is arranged to indicate the pressure being applied during diastole and systole of a patient whereby one may determine collapse of the retinal artery at the low point in the blood pressure cycle of a patient being examined as well as the rapid pulsation and then sustained collapse of such an artery at the peak of the blood pressure cycle as pressure is increased, said instrument constructed and arranged for operative interconnection with an illuminating source, and an ocular device for respectively illuminating a retinal artery of said eyeball through said lens while allowing visual examination of said eyeball artery.

2. An instrument according to claim 1 including an illumination means comprising a slit lamp and an ocular means comprising an examination microscope on an optical axis substantially common with that of the axis of said eyeball being examined.

3. The instrument of claim 1 in which the lens, along the illumination path, is a plano-thick-concave lens retained in a tubular support structure and in which the line-of-sight of an eyeball being examined is parallel to the axis of said tubular member.

4. An instrument according to claim 3 in which said lens has a cross-section dimension normal to its longitudinal axis in the range of 6 to 10 millimeters.

5. The instrument of claim 3 in which the lens has partially opaque side walls, said side walls extending substantially parallel to its geometrical axis.