Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant multi-organ condition occurring with a 1 in 3800 prevalence in Alberta. This genetic disorder leads to vascular malformations in different organs including the lungs and brain, commonly affecting pulmonary vasculature leading to pulmonary arteriovenous malformations (PAVMs). PAVMs lead to right-to-left shunts, which may be associated with neurologic complications. We aimed to evaluate and summarize the reported neurologic manifestations of individuals with HHT with pre-existing PAVMs.

We performed a qualitative systematic review to determine available literature on neurological complications among patients with PAVMs and HHT. Published studies included observational studies, case studies, prospective studies, and cohort studies including search terms HHT, PAVMs, and various neurologic complications using MEDLINE and EMBASE.

A total of 449 manuscripts were extracted including some duplicates of titles, abstracts, and text which were screened. Following this, 23 publications were identified for inclusion in the analysis. Most were case reports (n = 15). PAVMs were addressed in all these articles in association with various neurological conditions ranging from cerebral abscess, ischemic stroke, hemorrhagic stroke, embolic stroke, and migraines.

Although HHT patients with PAVMs are at risk for a variety of neurological complications compared to those without PAVMs, the quality and volume of evidence characterizing this association is low. Individuals with PAVMs have a high prevalence of neurological manifestations such as cerebral abscess, transient ischemic attack, cerebral embolism, hemorrhage, and stroke. Mitigating stroke risk by implementing proper standardized screening techniques for PAVMs is invaluable in preventing increased mortality.

To evaluate the treatment of intracranial abscess of otogenic origin, and to study the outcome measures of single stage treatment of the otogenic focus and drainage of intracranial abscess via a transmastoid approach.

Retrospective case review.

Dr Balabhai Nanavati Hospital and Medical Research Centre, Mumbai, India, an academic tertiary referral centre, and Shri H Bhagwati Municipal General Hospital, Mumbai, India, an academic secondary referral centre.

Seventy-three patients with intracranial abscess secondary to otogenic pathology, confirmed by computed tomographic scanning.

Single stage treatment of the ear pathology and drainage of intracranial abscess via a transmastoid approach, performed by the senior author (KPM).

Of the 73 patients, 12 were lost to follow up and were excluded from the study. Outcomes for the remaining 61 patients were known, and these patients were followed up for at least two years. Adults were more commonly affected by otogenic intracranial abscess than children, with a male preponderance. Otogenic intracranial abscess was associated with both cholesteatomatous (41 per cent) and non-cholesteatomatous ears (59 per cent). All cases were treated with transmastoid drainage of the intracranial abscess and canal wall up or down tympanomastoidectomy, depending on the ear pathology. Two cases developed post-operative cerebrospinal fluid leakage (3 per cent), and another two cases developed meningitis (3 per cent). Five patients had recurrent abscess; two of these patients (3 per cent) died but were included in the study. Three patients had residual abscess, improved with additional management.

In this series, the low morbidity and mortality rate, combined with a shorter hospital stay, suggest that single stage, transmastoid drainage of intracranial abscess and concurrent treatment of the otogenic pathology is an effective treatment for otogenic intracranial abscess.