Long-term outcomes of mesial temporal laser interstitial thermal therapy for drug-resistant epilepsy and subsequent surgery for seizure recurrence: a multi-centre cohort study

BACKGROUND

Magnetic resonance-guided laser interstitial thermal therapy (MRgLITT) is a minimally invasive alternative to surgical resection for drug-resistant mesial temporal lobe epilepsy (mTLE). Reported rates of seizure freedom are variable and long-term durability is largely unproven. Anterior temporal lobectomy (ATL) remains an option for patients with MRgLITT treatment failure. However, the safety and efficacy of this staged strategy is unknown.

METHODS

This multicentre, retrospective cohort study included 268 patients consecutively treated with mesial temporal MRgLITT at 11 centres between 2012 and 2018. Seizure outcomes and complications of MRgLITT and any subsequent surgery are reported. Predictive value of preoperative variables for seizure outcome was assessed.

RESULTS

Engel I seizure freedom was achieved in 55.8% (149/267) at 1 year, 52.5% (126/240) at 2 years and 49.3% (132/268) at the last follow-up ≥1 year (median 47 months). Engel I or II outcomes were achieved in 74.2% (198/267) at 1 year, 75.0% (180/240) at 2 years and 66.0% (177/268) at the last follow-up. Preoperative focal to bilateral tonic-clonic seizures were independently associated with seizure recurrence. Among patients with seizure recurrence, 14/21 (66.7%) became seizure-free after subsequent ATL and 5/10 (50%) after repeat MRgLITT at last follow-up≥1 year.

CONCLUSIONS

MRgLITT is a viable treatment with durable outcomes for patients with drug-resistant mTLE evaluated at a comprehensive epilepsy centre. Although seizure freedom rates were lower than reported with ATL, this series represents the early experience of each centre and a heterogeneous cohort. ATL remains a safe and effective treatment for well-selected patients who fail MRgLITT.

Robotic-assisted stereotactic percutaneous balloon compression for trigeminal neuralgia treatment

Trigeminal neuralgia (TN) is a facial pain disorder that can be a source of significant disability. Percutaneous balloon compression (PBC) has low cost, high efficacy, and minimal invasiveness. Complications can occur due to the balloon inflation or the needle placement itself. In this paper, we describe for the first time the clinical use of robotic-assistance to perform a PBC for TN, presenting our experience in two patients. The stereotactic planning targeted the foramen ovale (FO) establishing a safe and seamless needle trajectory. This yielded a streamlined, single pass needle placement and eliminated the need to "search" for the FO. There were no immediate complications and post-operatively both patients improved their symptoms. Robotic assistance is potentially a useful tool to reduce needle placement related complications, radiation exposure and PBC learning curve.

Genetic associations of intracranial aneurysm formation and sub-arachnoid hemorrhage

Risk factors for cerebral aneurysms typically include age, hypertension, smoking, and alcohol usage. However, the possible connection of aneurysms with genetic conditions such as Marfan's syndrome, polycystic kidney disease, and neurofibromatosis raises the question of possible genetic risk factors for aneurysm, and additionally, genetic risk factors for rupture. We conducted a literature review using the PubMed database for studies regarding genetic correlation with cerebral aneurysm formation as well as rupture from December 2008 to Jun 2015. Twenty-one studies related to IA formation and 10 concerning IA rupture that met our criteria were found and tabulated. The most studied gene and the strongest association was 9p21/CDKN2, which is involved in vessel wall remodelling. Other possible genes that may contribute to IA formation include EDNRA and SOX17; however, these factors were not studied as robustly as CDKN2. Multiple factors contribute to aneurysm formation and rupture and the contributions of blood flow dynamics and comorbidities as mentioned previously, cannot be ignored. While these elements are important to development and rupture of aneurysms, genetic influence may predispose certain patients to formation of aneurysms and eventual rupture.

Cervical puncture and perimedullary cistern shunt placement for idiopathic intracranial hypertension: An alternative to lumbar cistern or cerebral ventricular catheter placement a report of two cases

Objective:

Idiopathic intracranial hypertension (IIH) is a syndrome characterized by increased intracranial pressure (ICP) in the absence of an identifiable cause, and if untreated, can result in permanent vision loss. In symptomatic IIH patients, cerebrospinal fluid (CSF) diversion can lower ICP and protect vision; however, currently used CSF diversion systems are prone to malfunction in this population.

Materials and Methods:

In two IIH patients with histories of numerous prior shunt revisions that presented with proximal ventriculoperitoneal shunt malfunction, ICP reduction was achieved by an alternative surgical cerebrospinal fluid (CSF) diversion technique: Fluoroscopically guided, percutaneous placement of a catheter in the premedullary cistern and subsequent connection to the valve and distal shunt system.

Results:

Postoperatively, both patients’ papilledema resolved, headaches improved, and the shunts were working well at 3-month follow-up. At 1-year follow-up, one patient was well without papilledema or symptom recurrence, and the second patient had the shunt system removed by an outside surgeon.

Conclusion:

This technique may hold promise as an alternative shunting strategy in IIH patients with numerous proximal shunt failures or who are poor candidates for ventricular and lumbar shunts.