MRI findings in people with epilepsy and nodding syndrome in an area endemic for onchocerciasis: an observational study

Background

Onchocerciasis has been implicated in the pathogenesis of epilepsy. The debate on a potential causal relationship between Onchocerca volvulus and epilepsy has taken a new direction in the light of the most recent epidemic of nodding syndrome.

Objective

To document MRI changes in people with different types of epilepsy and investigate whether there is an association with O. volvulus infection.

Methods

In a prospective study in southern Tanzania, an area endemic for O. volvulus with a high prevalence of epilepsy and nodding syndrome, we performed MRI on 32 people with epilepsy, 12 of which suffered from nodding syndrome. Polymerase chain reaction (PCR) of O. volvulus was performed in skin and CSF.

Results

The most frequent abnormalities seen on MRI was atrophy (twelve patients (37.5%)) followed by intraparenchymal pathologies such as changes in the hippocampus (nine patients (28.1%)), gliotic lesions (six patients (18.8%)) and subcortical signal abnormalities (three patients (9.4%)). There was an overall trend towards an association of intraparenchymal cerebral pathologies and infection with O. volvulus based on skin PCR (Fisher''s Exact Test p=0.067) which was most pronounced in children and adolescents with nodding syndrome compared to those with other types of epilepsy (Fisher''s Exact Test, p=0.083). Contrary to skin PCR results, PCR of CSF was negative in all patients.

Conclusion

The observed trend towards an association of intraparenchymal cerebral pathological results on MRI and a positive skin PCR for O. volvulus despite negative PCR of CSF is intriguing and deserves further attention.     

Operative terminology and post-operative management approaches applied to hepatic surgery:Trainee perspectives

Outcomes in hepatic resectional surgery(HRS) have improved as a result of advances in the understanding of hepatic anatomy,improved surgical techniques, and enhanced peri-operative management.Patients are generally cared for in specialist higher-level ward settings with multidisciplinary input during the initial post-operative period,however,greater acceptance and understanding of HRS has meant that care is transferred,usually after 24-48 h,to a standard ward environment.Surgical trainees will be presented with such patients either electively as part of a hepatobiliary firm or whilst covering the service on-call,and it is therefore important to acknowledge the key points in managing HRS patients.Understanding the applied anatomy of the liver is the key to determining the extent of resection to be undertaken.Increasingly,enhanced patient pathways exist in the post-operative setting requiring focus on the delivery of high quality analgesia,careful fluid balance,nutrition and thromboprophlaxis.Complications can occur including liver,renal and respiratory failure,hemorrhage,and sepsis,all of which require prompt recognition and management.We provide an overview of the relevant terminology applied to hepatic surgery,an approach to the post-operative management,and an aid to developing an awareness of complications so as to facilitate better confidence in this complex subgroup of general surgical patients.