Third nerve palsy

Unruptured aneurysms not associated with SAH should normally be clipped or coiled if they are symptomatic, for instance if there is a third nerve palsy caused by a posterior communicating artery aneurysm (Fig. 30.2) (Raps et al. 1993). The optimal management of incidental unruptured asymptomatic aneurysms is unclear because the risk of rupture is... 

In tests of the response to direct light, a pupil that responds poorly clearly indicates the abnormal pupil.The differential diagnosis includes third-nerve palsy, anticholinergic mydriasis, Adie s pupil, or local iris disease. If each eye exhibits a good pupillary light reaction, differential diagnosis includes Horner s syndrome and physiologic anisocoria (Table 22-1). 

The following sections consider the most common disorders associated with a unilateral fixed and dilated pupil, including third-nerve palsy, anticholinergic mydriasis, iris sphincter atrophy, and adrenergic mydriasis. Because a dilated pupil does not always characterize Adie s syndrome, this disorder has been discussed separately. 

If, however, the patient exhibits only a unilateral fixed and dilated pupil without evidence of ptosis or extraocular muscle involvement, the clinician should perform the pilocarpine test, first using a 0.125% solution to reveal any cholinergic hypersensitivity as evidence for Adie s pupil. If there is no local iris damage by slit-lamp examination, no sector palsy of the iris sphincter, and no cholinergic hypersensitivity demonstrated by the 0.125% pilocarpine test, then the condition might be associated with interruption of the preganglionic innervation to the iris sphincter (i.e., third-nerve palsy). If the patient has third-nerve palsy, topically instilled pilocarpine in moderate concentrations activates the muscarinic receptor sites on the iris sphincter. Therefore if 0.125% pilocarpine reveals no cholinergic hypersensitivity, the practitioner... 

Figure 22-7 Complete third-nerve palsy. Note the left ptosis, exotropia, hypotropia, and dilated pupil.

Figure 22-8 Pilocarpine test in third-nerve palsy. (A) Before drug instillation. (B) After instillation of 1.0% pilocarpine, the pupil promptly constricts.

Intermittent exotropia Restrictive strabismus Third nerve palsies Sensory strabismus Paradoxical diplopia... 

Two patients with some of the classic neurological complications of fluorouracil have been reported. One had a cerebellar syndrome in association with global motor weakness and bulbar palsy and the other a bilateral third cranial nerve palsy (55). 

A third-nerve palsy occurred 36 hours after a second dose of sildenafil in a 56-year-old man. 

The radial nerve is closely applied to the humeral shaft in its middle and distal thirds. If, following manipulation of mid to lower third displaced fractures, a radial nerve palsy develops in association with soft tissue interposition on radiographs, sur-... 

Evaluation of specific clinical symptoms (i.e., third cranial nerve palsy) or non-specific symptoms in whom an aneurysm might explain the clinical presentation (thunderclap headache)... 

A 30-year-old man developed an isolated left abducens nerve palsy 1 day after removal of the mandibular right second and third molars under mandibular nerve block with 1.8 ml of articaine with 1 100 000 adrenaline. Multiple sclerosis was diagnosed because of the sudden onset of the symptom and the presence of typical MRI abnormahties. The symptoms subsided 20 days after starting glucocorticoid therapy. 

Pcom aneurysms are associated with third nerve cranial palsy with or without subarachnoid hemorrhage (Birchall et al. 1999 Perneczky and Czech 1984). From a surgical point of view the approach to these aneurysms is not too difficult. However, many of them have a small neck and are good candidates for endovascular therapy. In case of aneurysms smaller than 4mm we always use a microballoon in order to be prepared for eventual rupture occurring more often in this location than somewhere else (our experience We don t have any scientific data about... 

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