Homer’s syndrome

If the lesion of Homer s syndrome is postganglionic, indirectly acting sympathomimetics (eg, cocaine, hydroxyamphetamine) will not dilate the abnormally constricted pupil—because catecholamines have been lost from the nerve endings in the iris. In contrast, the pupil will dilate in response to phenylephrine, which acts directly on the receptors on the smooth muscle of the iris. A patient with a preganglionic lesion, on the other hand, will show a normal response to both drugs, since the postganglionic fibers and their catecholamine stores remain intact in this situation. 

The term Homer s syndrome is used to refer to any oculosympathetic palsy or paresis. 

Most lesions causing Homer s syndrome involve the preganglionic neuron. Patients with such lesions may have an apical lung tumor (Pancoast tumor) or breast malignancy that has spread to the thoracic outlet. The patient may also have a history of surgery or trauma to the neck, chest, or cervical spine. Nonoperative injuries to... 

Figure 22-2 Dilation lag in 72-year-old man with left-sided Homer s syndrome. (A) Obvious anisocoria in bright illumination. Note greater anisocoria at 4 to 5 seconds in darkness (B) as compared with the anisocoria at 10 to 12 seconds in darkness (C).

Apraclonidine Test. Apraclonidine 1% has shown promise in testing for Horner s syndrome. The drug should be instilled in both eyes. Significant pupillary dilation occurs in the eye with Horner s syndrome, whereas little or no dilation occurs in the normal eye. The up-regulation of a-receptors that occurs with sympathetic denervation in Horner s syndrome appears to unmask apraclonidine s tti effect in the eye with Homer s syndrome. 

Figure 22-3 Cocaine test for Homer s syndrome (same patient as in Figure 22-Z4). After instillation of 10% cocaine into each eye, dilation occurs in the normal right pupil but not in the left Homer s pupil.

Figure 22-5 Flow chart for management of the patient with Homer s syndrome of unknown etiology. (Modified from Grimson BS,Thompson HS. Raeder s syndrome. A clinical review. Surv Ophthalmol 1980 24 199-210.)...

A 48-year-old obese woman had a 22G interscalene catheter inserted under local anesthesia via a short-bevel stimulating needle. Anesthesia was achieved using 0.6% ropivacaine 40 ml followed by an infusion of ropivacaine 0.2% for effective analgesia. On day 3, she reported blurred vision and a painful neck swelling. She had developed a hematoma around the catheter insertion site (confirmed by ultrasound) and had an ipsilateral Homer s syndrome including myosis, ptosis, enophthalmos, ipsUateral anhidrosis, and conjunctival hyperemia. 

Neither patient was taking NSAIDs, aspirin, or anticoagulants. Catheters were removed immediately on diagnosis of hematoma formation. There was no neurological or sympathetic fiber damage to the upper limb in either patient, as tested by electroneuromyography and sympathetic skin response. Remission in both cases occurred within 1 year. There has been one previous report of prolonged Homer s syndrome in the absence of any obvious technical comphcation (67). Further studies into the use of interscalene catheters are needed to assess their propensity to cause this rare comphcation. 

Ophthalmological complications after intraoral anesthesia occurred in 14 cases over 15 years (98). The most common symptom was diplopia. Three patients developed Homer s syndrome, with ptosis, enophthalmos, and miosis on the same side as the anesthesia. Three patients developed mydriasis and ptosis. There was complete resolution in all patients. The authors postulated that direct diffusion of anesthetic solution from the pterygomaxillary fossa through the sphenomaxillary cavity to the orbit had caused the ophthalmological effects. 

In Homer s syndrome in the horse, topically instilled 10% phenylephrine produces periorbital sweating but its effects on pupil diameter and ptosis reversal are unpredictable. 

In one case a contralateral local anesthetic spread from an interscalene catheter infusion and caused Homer s syndrome [10 ]. 

A 56-year-old woman had an interscalene catheter inserted for lysis of adhesions of her shoulder. The initial injection of 0.5% ropivacaine 25 ml produced unilateral block and continuous interscalene infusion of 0.2% ropivacaine at 8 ml/hour via a disposable infusion pump was started. On the second postoperative day she developed bilateral Homer s syndrome with numbness in both shoulders. 

Nervous system A paravertebral infusion reportedly caused a transient brachial plexus palsy and Homer s syndrome [34 ]. 

The authors proposed that Homer s syndrome can result if sympathetic blockade extends upwards to involve the stellate ganglion. The brachial plexus palsy was explained by the fact that the stellate ganglion is in close proximity to the C7-T1 nerve roots feeding into the brachial plexus. Knowledge of the anatomy can prevent unnecessary imaging and anxiety, and simple discontinuation is sufficient treatment. 

Nervous system Homer s syndrome occurred in a patient who received a sagittal infraclavicular block with levobupivacaine... 

Two patients developed unilateral Homer s syndrome 20 minutes after a test dose of 3 ml of 1.5% lidocaine with adrenaline 1 200 000 in an epidural catheter at level T4/5 and T5/6 respectively [3 ]. In both cases epidural positioning of the catheter was demonstrated by CT epidurography. The symptoms resolved after 90 minutes and did not return after using the epidural catheter in theatre and postoperatively with bupivacaine 0.125% plus fentanyl 3 micrograms/ ml at an infusion rate of 6-9 ml/hour. 

Homer s syndrome due to extrapleural infusions is a rare complication, thought to indicate local anesthetic spread from the thoracic paravertebral to the cervical region [45"]. 

Grayson MF. Homer s syndrome after manipulation of tiie neck. Br MedJ 1987 295 1381-1382. 

A total of 3 cases of Homer s syndrome after obstetric epidural anaesthesia have recently been described (17 -, 18 -). In itself, this complication is not dangerous, but it may be a warning sign of an extensive block of serious consequence. Parturient women are more likely to develop this complication than are other patients because epidural injection with the patient in the lithotomy position can promote dissemination to higher levels (18 ). In some cases at least, the complication may be due to dissemination of the anaesthetic by way of the vertebral venous plexus (17 -). In view of the engorgement of the epidural veins during labour, this explanation is by no means improbable. 

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