Inferior oblique botulinum toxin as a postoperative test
Reviewed by Fiona Rowe

The authors aimed to evaluate the role of inferior oblique (IO) botulinum toxin (BT) injection as a surgical simulator prior to IO myectomy, i.e. preoperative diplopia test using BT. This was a retrospective review in a single centre over a 30-year period of 68 patients. Average age was 50 years with 51% female cases. BT type was 81% Xeomin, 18% Botox and 1% Dysport. All but 4% (paediatric cases) were done under topical anaesthesia. At 1-month follow-up, 71% reported improved symptoms, 17% no improvement and 6% transient diplopia. Six percent had unknown outcome. Of 48 cases showing improvement, 36 went on to surgery, 4 had repeat BT, 4 needed no further treatment and 4 await surgery. The results indicated IO BT as a useful predictor for surgical success prior to undergoing IO surgery and in identifying patients at risk of diplopia following surgery. Postoperative measures after surgery were comparable to measurements post BT.

Is inferior oblique botulinum toxin injection an effective surgical simulator prior to inferior oblique myectomy? A 30-year retrospective review. 
Norbury C, Shah H, Marsh I.
STRABISMUS
2025;33(3):166–73.