Cognitive and adaptive development of patients with tuberous sclerosis complex: A retrospective, longitudinal investigation
Department of Neurology, Massachusetts General Hospital, Boston, MA, USA. Epilepsy & Behavior
(Impact Factor: 2.26).
11/2011; 23(1):10-5. DOI: 10.1016/j.yebeh.2011.10.005
The aim of the work described here was to systematically analyze the developmental trajectory of patients with tuberous sclerosis complex (TSC).
A retrospective longitudinal chart review was performed, selecting patients who received multiple neuropsychological assessments. Intellectual/Developmental Quotients, Adaptive Behavior Composite scores, and clinical data were collected. On available EEGs, interictal epileptiform discharges were counted.
Sixty-six (18%) patients with TSC received multiple cognitive and adaptive development assessments. The mean intelligence of this study group remained relatively stable, albeit variable. Significant decline in adaptive functioning was observed, associated with lower age at seizure onset. Patients who underwent neurosurgery prior to baseline testing showed cognitive improvement. Developmental declines were significantly associated with increased numbers of antiepileptic drugs, with a trend toward association with mutation type and interictal epileptiform discharges.
This study suggests that the developmental course of patients with TSC may be altered by epilepsy comorbidity and neurosurgery, underlining the need for early and effective interventions in this population.
Available from: Elizabeth A Thiele
[Show abstract] [Hide abstract]
ABSTRACT: Tuberous sclerosis complex (TSC) is an autosomal dominant, multisystem disorder, which affects 1 in 6000 people. About half of these patients are affected by mental retardation, which has been associated with TSC2 mutations, epilepsy severity and tuber burden. The bimodal intelligence distribution in TSC populations suggests the existence of subgroups with distinct pathophysiologies, which remain to be identified. Furthermore, it is unknown if heterozygous germline mutations in TSC2 can produce the neurocognitive phenotype of TSC independent of epilepsy and tubers. Genotype-phenotype correlations may help to determine risk profiles and select patients for targeted treatments. A retrospective chart review was performed, including a large cohort of 137 TSC patients who received intelligence assessment and genetic mutation analysis. The distribution of intellectual outcomes was investigated for selected genotypes. Genotype-neurocognitive phenotype correlations were performed and associations between specific germline mutations and intellectual outcomes were compared. Results showed that TSC1 mutations in the tuberin interaction domain were significantly associated with lower intellectual outcomes (P<0.03), which was also the case for TSC2 protein-truncating and hamartin interaction domain mutations (both P<0.05). TSC2 missense mutations and small in-frame deletions were significantly associated with higher IQ/DQs (P<0.05). Effects related to the mutation location within the TSC2 gene were found. These findings suggest that TSC2 protein-truncating mutations and small in-frame mutations are associated with distinctly different intelligence profiles, providing further evidence that different types and locations of TSC germline mutations may be associated with distinct neurocognitive phenotypes.
[Show abstract] [Hide abstract]
ABSTRACT: Patients with tuberous sclerosis complex (TSC) often suffer from medically refractory epilepsy. Despite the multifocality of the disease, resection of the most epileptogenic tuber can lead to major improvement of seizure control. Therefore, non-invasive imaging methods are needed for detecting epileptogenic sources. We assessed the utility of electric source imaging (ESI) in the presurgical work-up of TSC patients and its combination with Positron Emission Tomography (PET) and ictal/interictal Single Photon Emission Computed Tomography (SISCOM).
Thirteen patients underwent high density ESI (8/13) and/or low density ESI (13/13). We investigated the concordance between ESI, PET, SISCOM and the resection area in the 11 operated patients (nine seizure-free).
High resolution ESI was partially or completely concordant with the resected area in 5/5 seizure free patients. Low resolution ESI was partially or completely concordant in 7/9 seizure free patients. PET and SPECT were concordant (partially or completely) in 8/9 and 6/9 cases, respectively. We found multifocal ESI sources in 2/9 seizure free patients, marked multifocal PET hypometabolism in 3/9 and multifocal SISCOM in 4/9. The region of concordant ESI and PET accurately predicted the dominant epileptogenic source in 6/9 patients. The same was true for concordant ESI and SISCOM in 4/9 patients, whereas the coregistration of only PET and SISCOM was insufficient in 3/9 successfully operated cases. The combination of all three imaging modalities could successfully identify the resection area in all but one patient with a favorable post-operation outcome.
ESI is an important tool for the pre-surgical evaluation of TSC patients. It complements PET and SPECT results and can improve the management of candidates for surgery when integrated with electro-clinical information.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.