The radiographic appearance and clinical presentation of vertebrobasilar dolichoectasia are variable. In some patients, it is clinically silent and represents an incidental radiographic finding. In other cases, such tortuosity produces neurologic dysfunction by a variety of mechanisms. There may be direct compression of the brainstem or cranial nerves, strokelike events related to thrombosis, microembolization or hemodynamic disturbance, and occasionally hydrocephalus. A causal relationship between a particular clinical finding and this radiologic anomaly should be made only after exclusion of other possible causes. MRI combined with MRA is the optimal imaging technique for evaluating the anatomical relationship between vessels and neural structures, particularly vascular compression of cranial nerves. Isolated cranial nerve involvement, as in the patient described above, may be the sole manifestation of vertebrobasilar dolichoectasia, and any cranial nerve except the olfactory nerve is susceptible (Figure 5.6).

Management of patients with neurologic manifestations related to vertebrobasilar dolichoectasia is generally conservative. Most patients do not progress beyond an isolated cranial neuropathy and are treated with observation, prisms and occasionally strabismus surgery.

FURTHER READING

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M. Ada, A. Kaytaz, K. Tuskan, M. G. Guvenc, H. Silcuk, Isolated sphenoid sinusitis presenting with unilateral VIth nerve palsy. International J Ped Otorhinolaryngol, 68

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