Patent Application
20190125585
The present invention relates generally to medical instruments and, more particularly, to a scleral marker for use in ophthalmic procedures.
In many ophthalmic procedures it is essential to locate the point of injection into the scleral limbal tissue at a precise location in order to ensure safety not only of the eye lens but also the PARS Plana region. For a human adult eye, the safe PARS Plana region lies at about 3.5 mm from the outer edge of the iris. Such a position essentially ensures not only safety of the retina, but also protects the lens from damage.
In order to facilitate the correct position in the scleral before the injection, there have been previously known devices known as “Melki” markers. This previously known Melki marker include an elongated handle dimensioned to be held in the hand of the surgeon. A pair of pointers extend outwardly from one end of the handle in the free ends of these two pointers are separated from each other by the desired distance, e.g. 3.5 mm.
In use, a Melki marker is pressed against the eye and moved for a short distance along the outside of the iris thus causing a depression in the sclera. It has been found that insertion of a needle through the depressed area, necessary for many medical procedures, is essentially painless to the patient.
In practice, however, it is difficult for even skilled ophthalmic surgeons to constantly accurately inject the needle into the depression caused by the Melki marker. When this happen; the patient feel a pain sensation in the eye. In Opthamology, however, the avoidance of pain for the patient is paramount.
The present invention provides a surgical instrument for marking spots at locations on the scleral limbal surface of the human eye which avoids the previous known disadvantages of the Melki marker.
In brief, the surgical instrument of the present invention comprises an elongated handle preferably having a bend of about 150° at a point along its length. The handle may be constructed of any suitable material, such as stainless steel.
A first elongated pointer extends substantially axially outwardly from one end of the handle. This pointer has a dull pointed free end which, when pressed against the scleral limbal surface, creates a depression, but not an incision, in the scleral surface having a first area. This first area amounts to a little more than a point on the eye.
A second elongated pointer also extends substantially axially outwardly from the end of the handle, and is positioned about 3.5 mm from the first elongated pointer at their free ends. The second pointer, however, unlike the first pointer, has the blunt free end which, when pressed against the scleral libral surface, creates a depression in the scleral surface. The surface, furthermore, has a second area which is several times the area of the depression of the first pointer. As such, the second pointer creates a relatively large depression, when pressed against the eye, e.g. about 1 mm. Such a relatively large mark in the eye is relatively simple for the doctor to hit when injecting into the eye.
A better understanding of the present invention will be had upon reference to the following detailed description when read in conjunction with the accompany drawing, wherein like reference numerals refer to like parts throughout the several views, and in which:
With reference first to
The instrument 10 includes an elongated handle 12 which is dimension to comfortably fit within the hand of the eye surgeon. The handle 12 is elongated and typically 80-100 mm in length. The handle 12 also includes a bend 14 and an intermediate point along its length and this bend is typically about 150°.
The handle 12 may be constructed of any simple material, such as stainless steel. Other materials, however, maybe used without deviation from either the spirit or scope of the invention.
A first elongated pointer 16 is secured to and extends generally axially outwardly from one end 18 of the handle 12. A free end 20 over pointer 16 is generally come in shaped so that the free end 22 of the pointer 16 has a small area of contact, i.e. less than ½ mm square in size. Furthermore, pressing the pointed end 22 of the pointer 16 against the human eye will not puncture the scleral.
A second pointer 26 also extends substantially axially outwardly from the end 18 of the handle 12. Unlike the first pointer 16, however, a second pointer 26 terminates in a blunt end 28 which is preferably circular in shape. Furthermore, the blunt end 28 is dimension so that, with the blunt end 28 of the second pointer 28 and end 22 of the first pointer 16 of the instrument 10 press against the eye, area of contact between the blunt end 28 and the human eye is several times the area of contact between the pointed end 22 and the human eye.
The ends 22 and 28 of the pointers, 16 and 26 are spaced apart from each other by distance that is preferably 2 mm or less. Thus the pointer end 28 can be safely positioned outside the lens and in front of the retina of a human.
With reference now to
With reference now to
Even though the blunt end 28 of the instrument 10 creates a slight depression in the scleral of the eye, the depression is only temporary. After a short time, the scleral returns to its natural original shape without any known adverse effects.
From the foregoing, it can be seen in the present inventions provides a surgical instrument for ophthalmic surgery on human beings which facilitates not only the location of the PARS Plana area for injection into the eye, but also reduces pain and discomfort during the subsequent surgical operation of the injection.
Having described my invention, many modifications thereto will become apparent to those skilled in the art to which it pertains without deviation from the spirit of the invention as defined by the scope of the appended claims.
