Pain Score in Adjustable Strabismus Surgery
Topical
anesthesia
with
proparacaine
and stereopsis were assessed by the Titmus fly test and
Worth four dot test in every case. A thorough eye
examination was performed including fundus and
intraocular pressures. In case of significant oblique
overaction, paralytic or vertical strabismus, fundus
torsion was also assessed with the indirect
ophthalmoscope. All surgeries were performed by the
hydrochloride 0.5% has been a safe and effective tool
during the final suture adjustment and has been
advocated by many strabismus surgeons4,5,6. Seijas7 et
al recommend topical anesthesia only, for strabismus
surgery even without the need of a general anesthetic.
The rationale of our study was to assess the pain
score at the time of suture adjustment after strabismus
surgery using two scales, in order to find out if it is a
comfortable and effective procedure.
author under general anesthesia.
A
drop of
phenylephrine 10% (Ethifrin®) was instilled into the
conjunctival sac prior to the surgery in each eye. The
fornix approach for strabismus surgery was used in
every case. Each muscle was hooked, and then secured
with a double armed 6 – 0 vicryl (polyglactin 910)
absorbable suture, which was passed through the
sclera at muscle insertion, or transposed above or
below the insertion in case of “A” or “V” patterns, in a
‘hang-back’ fashion. The muscles placed for
adjustable purpose were held in position by Guyton‟s9
modification of the sliding noose knot, which was
fashioned with a 6 – 0 vicryl suture. The amount of
‘hang-back’ recession was calculated for each patient
using standard tables10-12. The traction suture for
holding the sclera for postoperative adjustment was
created with ethibond 5-0 in every case. For the non-
adjustable recessions, the muscle was tied and allowed
to ‘hang-back’ from its insertion, with the amount of
recession calculated as required. For resections, the
amount of resection was overcorrected by 2 mm, and
allowed to ‘hang-back’ for this distance, to be adjusted
if required postoperatively. At least one muscle was
kept on an adjustable sliding noose knot per case; with
complex strabismus, all muscles were kept on
adjustable sutures.
MATERIAL AND METHODS
A total of 33 patients were included in this study by
convenient sampling technique. The study was carried
out in the Department of Ophthalmology, Fauji
Foundation Hospital, Rawalpindi; a tertiary care
teaching hospital affiliated with the Foundation
University Medical College. Approval from the ethical
committee was taken. Horizontal, vertical and
complex strabismus cases were included along with
patients with a previous history of strabismus surgery.
Myasthenia gravis and uncooperative children less
than 7 years of age were excluded.
A detailed ocular assessment was done and best-
corrected visual acuity was documented for every
case. Refractive correction was given to the patients
before surgery. The prism cover test (PCT) was used
to assess the preoperative angle of deviation with the
refractive correction in place, for both near and
distance in primary gaze position, as well as in 25° of
upgaze (chin down) and 35° of downgaze (chin up)8,
right and left gaze, and head tilt in case of paralytic
strabismus. In certain cases of sensory strabismus with
poor fixation, the Krimsky test was used for analysis
of the angle or a pen torch used as a target for near and
distance. The distance angle in primary position with
the refractive correction in place was considered as the
angle of deviation in all cases, and the surgical
alignment was sought to correct this angle, although at
the time of suture adjustment, both near and distance
alignment was corrected. Exception to this was
accommodative refractive esotropia, for which the
near deviation with distance spectacles in place was
considered for correction of the alignment.
All patients were assessed for alignment and final
adjustment at least 1 hour or more after surgery, in the
recovery room, to allow the effects of general
anesthesia to wear off. The eyes were anesthetized
topically with Alcaine® (proparacaine hydrochloride
0.5%) eye drops a few times. The patients were fully
conscious at the time of suture adjustment and were
not placed on a monitor. However, they were observed
for discomfort, syncope or oculocardiac reflex. The
patients were assessed with the cover-uncover test at
distance and near, with a torch light for distance if the
vision was blurred, or a distance readable target; and
for near an accommodative target was used. If the
alignment was satisfactory, with no movement on
cover testing, the sutures were tied off in their existing
position, held in place by the sliding noose, which was
removable after tying the ends of the muscle sutures.
The measurements were taken by the operating
surgeon and repeated one day prior to the surgery, to
obtain maximum cosmesis. Extraocular motility was
checked with muscle overaction graded from +1 to +4
and underaction graded from -1 to -5. Binocular vision
Pakistan Journal of Ophthalmology, 2020, Vol. 36 (2): 109-114
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