The role of botulinum toxin in third nerve palsy

Botulinum Toxin Injection for the Treatment of Third, Fourth, and Sixth Nerve Palsy: A Meta-Analysis

The efficacy of botulinum toxin injection for the treatment of third, fourth, and sixth nerve palsy was evaluated. PubMed, Scopus, EMBASE, Web of Science, and Google Scholar databases were searched. Data about the duration of palsy (acute vs chronic), cause of the palsy, type of toxin used, mean dose, and other background characteristics were collected. Outcome variables were success rate (defined by alleviation of diplopia or reduction in eye deviation) and standardized mean difference of prism diopter and abduction deficit before and after injection. The Joanna Briggs Institute checklist was implemented for the risk of bias assessment. The analysis included 38 articles, comprising 643 patients. The overall treatment success rate in acute and chronic nerve palsy was 79% and 33%, respectively. The success rate was not significantly different between different subgroups of age, type of botulinum toxin, pre-injection prism diopter, etiology of the palsy, duration of follow-up, and mean dose of botulinum toxin injection. However, in both acute and chronic palsy, diabetes etiology was accompanied by the highest success rate. Overall symptomatic response to botulinum injection was 84% (95% CI: 67% to 96%), whereas functional response was observed in 64% (95% CI: 47% to 79%) of the patients. The odds ratio for the success rate of treatment of palsies with botulinum toxin versus expectant management was 2.67 (95% CI: 1.12 to 6.36) for acute palsy and 0.87 (95% CI: 0.17 to 4.42) for chronic palsy. Botulinum toxin can be used for the treatment of acute third, fourth, and sixth nerve palsy, especially in patients with acute palsy and more severe tropia. [J Pediatr Ophthalmol Strabismus. 2024;61(3):160-171.].

Vision impairment after traumatic brain injury: present knowledge and future directions

Traumatic brain injury (TBI) is a major cause of mortality and morbidity in the USA as well as in the world. As a result of TBI, the visual system is also affected often causing complete or partial visual loss, which in turn affects the quality of life. It may also lead to ocular motor dysfunction, defective accommodation, and impaired visual perception. As a part of the therapeutic strategy, early rehabilitative optometric intervention is important. Orthoptic therapy, medication, stem cell therapy, motor and attention trainings are the available treatment options. Gene therapy is one of the most promising emerging strategies. Use of state-of-the-art nanomedicine approaches to deliver drug(s) and/or gene(s) might enhance the therapeutic efficacy of the present and future modalities. More research is needed in these fields to improve the outcome of this debilitating condition. This review focuses on different visual pathologies caused by TBI, advances in pre-clinical and clinical research, and available treatment options.

Transposition of Both Oblique Muscles Combined With Lateral Rectus Botulinum Toxin Injection and Globe Fixation Suture in the Treatment of Congenital Cranial Nerve III Palsy

The authors report a new technique to treat complete cranial nerve III palsy. A 15-year-old girl underwent botulinum toxin injection into the lateral rectus muscle, nasal transposition of both the superior and inferior oblique muscles to the medial rectus insertion, and absorbable suture globe fixation to the nasal orbital periosteum. Six months postoperatively, her primary position eye deviation was within 12 prism diopters of orthotropia with limitation of ductions in all directions. [J Pediatr Ophthalmol Strabismus. 2017;54:e13-e17].

Infranuclear ocular motor disorders

This chapter covers the very large number of possible disorders that can affect the three ocular motor nerves, the neuromuscular junction, or the extraocular muscles. Conditions affecting the nerves are discussed under two major headings: those in which the site of damage can be anatomically localized (e.g., fascicular lesions and lesions occurring in the subarachnoid space, the cavernous sinus, the superior orbital fissure, or the orbit) and those in which the site of the lesion is either nonspecific or variable (e.g., vascular lesions, tumors, "ophthalmoplegic migraine," and congenital disorders). Specific comments on the diagnosis and management of disorders of each of the three nerves follow. Ocular motor synkineses (including Duane's retraction syndrome and aberrant regeneration) and disorders resulting in paroxysms of excess activity (e.g., neuromyotonia) are then covered, followed by myasthenia gravis and other disorders that affect the neuromuscular junction. A final section discusses disorders of the extraocular muscles themselves, including thyroid disease, orbital myositis, mitochondrial disease, and the muscular dystrophies.

The role of Botulinum toxin in management of acute traumatic third-nerve palsy

PURPOSE

To study the effect of botulinum toxin A injection in the management of paralytic exotropia resulting from acute traumatic third (oculomotor) nerve palsy.

METHODS

Nine patients with acute traumatic partial third-nerve palsy of less than 2 months' duration were treated by injection of botulinum toxin A into the ipsilateral lateral rectus muscle. The horizontal deviation angles before and after the injections were recorded. A distance exotropia of less than 10(Delta) or absence of diplopia in the primary position at the last follow-up was defined as recovery.

RESULTS

The mean preinjection deviation in the primary position was 48.3(Delta) of exotropia, and the mean postinjection deviation in the primary position was 14.2(Delta) at the last follow-up. Seven patients experienced recovery and regained single binocular vision in the primary position. The overall recovery rate was 77.8%. Two patients did not recover and subsequently underwent strabismus surgery.

CONCLUSIONS

Patients with acute traumatic partial third-nerve palsy treated by injection of botulinum toxin A in the lateral rectus muscle showed marked recovery when injection was performed within 2 months of the onset of palsy. Botulinum toxin injection into the lateral rectus muscle may provide temporary relief of symptoms in some patients and seems to be a useful treatment option in cases of acute traumatic third nerve palsy in the short-term.

Botulinum toxin and the eye

Botulinum toxin in ophthalmology is used to reduce the function of the eyelid muscles in spasms or therapeutically. Therapeutic and diagnostic use in strabismus is also discussed, along with the controversial treatment of nystagmus.

Botulinum toxin in fourth nerve palsies

BACKGROUND

Botulinum toxin A (BTXA) has not been used routinely in the management of fourth nerve (IV N) palsy. However, it is known that the results of surgery can be unpredictable with a risk of over- or under-correction.

METHODS

The results were reviewed of 20 patients, aged 19-70 years, with unilateral and bilateral IV N palsies who received BTXA injections to the inferior oblique or inferior rectus muscles. The aetiology was congenital in 12 (60%), traumatic in six (30%), due to myasthenia in one (5%), and unclear in one (5%). Fifty per cent of patients had had previous strabismus surgery to a maximum of four procedures. The mean pre-injection vertical deviation was 11 prism dioptres. All but two patients had a single injection. Average follow-up was 19 months.

RESULTS

Ten patients (group I) received BTXA as a primary therapy. Following inferior oblique injection, six patients received little benefit and went on to surgery (83%) or continued with prisms (17%). Five patients from group I who had inferior rectus toxin were discharged symptom-free. Group 2 (10 patients) received BTXA for residual deviations postoperatively; in this group all except one patient with no fusion achieved long-term benefit following inferior rectus BTXA. In those who had inferior oblique injections, BTXA was useful in one patient (25%). Inferior rectus injection produced a greater chance of temporary reversal of the deviation.

CONCLUSIONS

BTXA is of greatest benefit in patients with residual deviations particularly when the inferior rectus is injected, but is of limited value as a primary therapy in chronic IV N palsy.