left iris. The surgery on her right eye
required a sector iridectomy, consisting of removal of a larger U-shaped section
of her iris extending vertically from the edge of the iris to the pupil and
horizontally, as if looking at the face of a clock, from approximately the 11:00
to the 1:00 o'clock position.
Lens implantation contemporaneous with cataract surgery was not available
when Alston's surgery was performed. Alston contacted Dr. Marvelli in April of
1996, at age 59, seeking secondary implantation of intraocular lenses in both of
her eyes. "Secondary" refers to implantation performed subsequent to
earlier cataract surgery. If successfully implanted, the lenses would improve
Alston's vision and free her from the need for cataract spectacles or contacts.
Dr. Marvelli is a board certified ophthalmologist specializing in lens
implant procedures and has maintained a large practice in FortWorth, Texas for
fifteen years, performing 100 to 200 surgeries per week. Dr. Marvelli discussed
the implant procedure with Alston, including the risks of blindness and the loss
of her eye, and offered her the alternative options of contact lenses or a new
prescription for glasses. Alston chose the implant surgery.
On May 6, 1996, Dr. Marvelli performed a secondary anterior chamber
intraocular lens implantation procedure on Alston's right eye. "Anterior
chamber" means placement of the lens implant in front of the iris. Dr.
Marvelli's surgical technique consisted of making a "superior"
incision, that is, at the top of the eye, inserting a multiflex lens, and
rotating the lens so that "haptics," S-shaped loops at the top and
bottom of the lens, were positioned on the sclera spur of the iris between the
1:00 and 2:00 o'clock and 7:00 and