Intensive mobility training postcerebral hemispherectomy: early surgery shows best functional improvements.

BACKGROUND: Limited research exists on rehabilitative techniques focused on reducing disabilities after cerebral hemispherectomy despite persistent hemiparesis. OBJECTIVES: The efficacy of Intensive Mobility Training (IMT) for improving gait, balance and mobility was evaluated in patients after cerebral hemispherectomy and compared with clinical variables for signs of developmental neuroplasticity. METHODS: Participants (N.=19; 13.8±5.7 years) postcerebral hemispherectomy received IMT, three hours/day for 10 days. Outcomes measures were assessed pre- and post-intervention using the GAITRite electronic walkway® (velocity, toe in/out, step length of affected an unaffected leg), Dynamic Gait Index, Fugl-Meyer Scale, Berg Balance Scale, Timed Up and Go and Six-Minute Walk Test. Six of the nine measures that showed moderate effect sizes were incorporated into a Combined Functional Index (CFI) to assess global impact of therapy. RESULTS: After IMT, improvements were identified for toe in/out, step length of unaffected leg, Dynamic Gait Index, Berg Balance Scale and Six-Minute Walk (P<0.05; Effect Size 0.36-0.50). Using CFI for these six measures, patients improved from 77.3% to 82.7% (+5.3±3.7%) of normal following IMT. Improvements in CFI were greater in patients five years or younger at time of surgery (+7.7±3.6%) compared with older patients (+3.2±2.5%), and this accounted for 22% of variability in the change in score. CONCLUSION: The younger the participant at time of surgery correlated with the greatest improvements following IMT. These findings support the concept that the remaining hemisphere retains greater neuroplasticity if the contralateral surgery occurs earlier in cerebral development.

Cerebral hemispherectomy: hospital course, seizure, developmental, language, and motor outcomes.

OBJECTIVE: To compare hemispherectomy patients with different pathologic substrates for hospital course, seizure, developmental, language, and motor outcomes. METHODS: The authors compared hemispherectomy patients (n = 115) with hemimegalencephaly (HME; n = 16), hemispheric cortical dysplasia (hemi CD; n = 39), Rasmussen encephalitis (RE; n = 21), infarct/ischemia (n = 27), and other/miscellaneous (n = 12) for differences in operative management, postsurgery seizure control, and antiepilepsy drug (AED) usage. In addition, Vineland Adaptive Behavior Scale (VABS) developmental quotients (DQ), language, and motor assessments were performed pre- or postsurgery, or both. RESULTS: Surgically, HME patients had the greatest perioperative blood loss, and the longest surgery time. Fewer HME patients were seizure free or not taking AEDs 1 to 5 years postsurgery, but the differences between pathologic groups were not significant. Postsurgery, 66% of HME patients had little or no language and worse motor scores in the paretic limbs. By contrast, 40 to 50% of hemi CD children showed near normal language and motor assessments, similar to RE and infarct/ischemia cases. VABS DQ scores showed +5 points or more improvement postsurgery in 57% of patients, and hemi CD (+12.7) and HME (+9.1) children showed the most progress compared with RE (+4.6) and infarct/ischemia (-0.6) cases. Postsurgery VABS DQ scores correlated with seizure duration, seizure control, and presurgery DQ scores. CONCLUSIONS: The pathologic substrate predicted pre- and postsurgery differences in outcomes, with hemimegalencephaly (but not hemispheric cortical dysplasia) patients doing worse in several domains. Furthermore, shorter seizure durations, seizure control, and greater presurgery developmental quotients predicted better postsurgery developmental quotients in all patients, irrespective of pathology.

Spoken language outcomes after hemispherectomy: factoring in etiology.

We analyzed postsurgery linguistic outcomes of 43 hemispherectomy patients operated on at UCLA. We rated spoken language (Spoken Language Rank, SLR) on a scale from 0 (no language) to 6 (mature grammar) and examined the effects of side of resection/damage, age at surgery/seizure onset, seizure control postsurgery, and etiology on language development. Etiology was defined as developmental (cortical dysplasia and prenatal stroke) and acquired pathology (Rasmussen's encephalitis and postnatal stroke). We found that clinical variables were predictive of language outcomes only when they were considered within distinct etiology groups. Specifically, children with developmental etiologies had lower SLRs than those with acquired pathologies (p =.0006); age factors correlated positively with higher SLRs only for children with acquired etiologies (p =.0006); right-sided resections led to higher SLRs only for the acquired group (p =.0008); and postsurgery seizure control correlated positively with SLR only for those with developmental etiologies (p =.0047). We argue that the variables considered are not independent predictors of spoken language outcome posthemispherectomy but should be viewed instead as characteristics of etiology.

Language after hemispherectomy.

We studied the spoken language of 49 children who had undergone hemispherectomy as part of the UCLA Pediatric Epilepsy Surgery Research Program and analyzed, among a number of clinical factors, the relation between acquired vs developmental pathology and spoken language outcomes. In this paper we will briefly review the results of our study and attempt to explain (1) why "the early" is not always better, (2) why so many right hemispherectomies fail to develop language, and (3) why some left hemispherectomized children develop remarkably good language despite removal of the "language" hemisphere. This account will rest on the proposed model of brain maturation and progressive lateralization.

Age and etiology as predictors of language outcome following hemispherectomy.

We report on the effects of etiology and age on the linguistic outcomes in a large pediatric hemispherectomy population. Four populations were considered separately: cortical dysplasia (multilobar involvement), Rasmussen's encephalitis, infarction as a primary etiology and, fourth, children who failed to develop language, regardless of etiology. We argue against the 'the-earlier-the-better' hypothesis and propose our own hypothesis that weds maturational factors to etiological factors to predict language outcomes following pervasive brain insult. The implications of our 'critical impact point' hypothesis are discussed.