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Yu Lei, Yan-Jiang Li, Qi-Hao Guo, Xing-Dang Liu, Zhuang Liu, Wei Ni, Jia-Bin Su, Heng Yang, Han-Qiang Jiang, Bin Xu, Yu-Xiang Gu and Ying Mao

OBJECTIVE

Chronic frontal hemodynamic disturbances are associated with executive dysfunction in adult patients with moyamoya disease (MMD). However, the impact of surgical revascularization on executive dysfunction and its underlying mechanism remains unclear. The aim of the present study was to examine the postoperative radiological correlates of cognitive improvement and thereby explore its underlying mechanism.

METHODS

Fourteen patients who met the inclusion criteria were identified at Huashan Hospital, were operated on, and were successfully followed up for 6 months. Postoperative changes in cortical perfusion and regional amplitude of low-frequency fluctuations (ALFF) were examined by SPECT and resting-state functional MRI, respectively. Executive function was evaluated by 2 tests (Trail Making Test Part B and the summation of executive subtests of Memory and Executive Screening [MES-EX]). Follow-up neuropsychological outcomes were then correlated with radiological changes to identify nodes functioning as leading contributors to postoperative executive outcomes.

RESULTS

All patients underwent successful unilateral bypass procedures, with some operations performed on the left side and some on the right side. At the 6-month follow-up, the baseline and follow-up test scores for the different sides did not differ significantly. The group with good collaterals (Matsushima Grade A, 9 patients) exhibited significantly increased postoperative perfusion (change in [△] hemodynamics) in bilateral frontal (left, p = 0.009; right, p = 0.003) and left parietal lobe (p = 0.014). The Spearman's correlation test suggested that only the right frontal lobe exhibited significant positive postoperative radiological correlates with cognitive performance (△MES-EX vs △hemodynamics, r = 0.620, p = 0.018; △MES-EX vs △ALFF, r = 0.676, p = 0.008; △hemodynamics vs △ALFF, r = 0.547, p = 0.043). Subsequent regional ALFF analysis revealed that the right dorsolateral prefrontal cortex (DLPFC) was the only node in the responsible hemisphere to exhibit significant postoperative changes.

CONCLUSIONS

The results not only advance our understanding of pathological interactions of postoperative executive performance in adult MMD, but also indicate that the right DLPFC amplitude might be a quantitative predictor of postoperative executive control improvement.

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Han Yan, Eric Toyota, Melanie Anderson, Taylor J. Abel, Elizabeth Donner, Suneil K. Kalia, James Drake, James T. Rutka and George M. Ibrahim

OBJECTIVE

Drug-resistant epilepsy (DRE) presents a therapeutic challenge in children, necessitating the consideration of multiple treatment options. Although deep brain stimulation (DBS) has been studied in adults with DRE, little evidence is available to guide clinicians regarding the application of this potentially valuable tool in children. Here, the authors present the first systematic review aimed at understanding the safety and efficacy of DBS for DRE in pediatric populations, emphasizing patient selection, device placement and programming, and seizure outcomes.

METHODS

The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and recommendations. Relevant articles were identified from 3 electronic databases (MEDLINE, Embase, and Cochrane CENTRAL) from their inception to November 17, 2017. Inclusion criteria of individual studies were 1) diagnosis of DRE; 2) treatment with DBS; 3) inclusion of at least 1 pediatric patient (age ≤ 18 years); and 4) patient-specific data. Exclusion criteria for the systematic review included 1) missing data for age, DBS target, or seizure freedom; 2) nonhuman subjects; and 3) editorials, abstracts, review articles, and dissertations.

RESULTS

This review identified 21 studies and 40 unique pediatric patients (ages 4–18 years) who received DBS treatment for epilepsy. There were 18 patients with electrodes placed in the bilateral or unilateral centromedian nucleus of the thalamus (CM) electrodes, 8 patients with bilateral anterior thalamic nucleus (ATN) electrodes, 5 patients with bilateral and unilateral hippocampal electrodes, 3 patients with bilateral subthalamic nucleus (STN) and 1 patient with unilateral STN electrodes, 2 patients with bilateral posteromedial hypothalamus electrodes, 2 patients with unilateral mammillothalamic tract electrodes, and 1 patient with caudal zona incerta electrode placement. Overall, 5 of the 40 (12.5%) patients had an International League Against Epilepsy class I (i.e., seizure-free) outcome, and 34 of the 40 (85%) patients had seizure reduction with DBS stimulation.

CONCLUSIONS

DBS is an alternative or adjuvant treatment for children with DRE. Prospective registries and future clinical trials are needed to identify the optimal DBS target, although favorable outcomes are reported with both CM and ATN in children.

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Han Yan, Nebras M. Warsi, Abhaya V. Kulkarni, James M. Drake and George M. Ibrahim

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Xu-Yun Hua, Bin Liu, Yan-Qun Qiu, Wei-Jun Tang, Wen-Dong Xu, Han-Qiu Liu, Jian-Guang Xu and Yu-Dong Gu

Object

Contralateral C-7 nerve transfer was developed for the treatment of patients with brachial plexus avulsion injury (BPAI). In the surgical procedure the affected recipient nerve is connected to the ipsilateral motor cortex, and the dramatic peripheral alteration may trigger extensive cortical reorganization. However, little is known about the long-term results after such specific nerve transfers. The purpose of this study was to investigate the long-term cortical adaptive plasticity after BPAI and contralateral C-7 nerve transfer.

Methods

In this study, 9 healthy male volunteers and 5 male patients who suffered from right-sided BPAI and had undergone contralateral C-7-transfer more than 5 years earlier were included. Functional MRI studies were used for the investigation of long-term cerebral plasticity.

Results

The neuroimaging results suggested that the ongoing cortical remodeling process after contralateral C-7 nerve transfer could last for a long period; at least for 5 years. The motor control of the reinnervated limb may finally transfer from the ipsilateral to the contralateral hemisphere exclusively, instead of the bilateral neural network activation.

Conclusions

The authors believe that the cortical remodeling may last for a long period after peripheral rearrangement and that the successful cortical transfer is the foundation of the independent motor recovery.

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Han Yan, Taylor J. Abel, Naif M. Alotaibi, Melanie Anderson, Toba N. Niazi, Alexander G. Weil, Aria Fallah, John H. Phillips, Christopher R. Forrest, Abhaya V. Kulkarni, James M. Drake and George M. Ibrahim

OBJECTIVE

In this systematic review and meta-analysis the authors aimed to directly compare open surgical and endoscope-assisted techniques for the treatment of sagittal craniosynostosis, focusing on the outcomes of blood loss, transfusion rate, length of stay, operating time, complication rate, cost, and cosmetic outcome.

METHODS

A literature search was performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant articles were identified from 3 electronic databases (MEDLINE, EMBASE, and CENTRAL [Cochrane Central Register of Controlled Trials]) from their inception to August 2017. The quality of methodology and bias risk were assessed using the Effective Public Health Practice Project Quality Assessment Tool for Quantitative Studies. Effect estimates between groups were calculated as standardized mean differences with 95% CIs. Random and fixed effects models were used to estimate the overall effect.

RESULTS

Of 316 screened records, 10 met the inclusion criteria, of which 3 were included in the meta-analysis. These studies reported on 303 patients treated endoscopically and 385 patients treated with open surgery. Endoscopic surgery was associated with lower estimated blood loss (p < 0.001), shorter length of stay (p < 0.001), and shorter operating time (p < 0.001). From the literature review of the 10 studies, transfusion rates for endoscopic procedures were consistently lower, with significant differences in 4 of 6 studies; the cost was lower, with differences ranging from $11,603 to $31,744 in 3 of 3 studies; and the cosmetic outcomes were equivocal (p > 0.05) in 3 of 3 studies. Finally, endoscopic techniques demonstrated complication rates similar to or lower than those of open surgery in 8 of 8 studies.

CONCLUSIONS

Endoscopic procedures are associated with lower estimated blood loss, operating time, and days in hospital. Future long-term prospective registries may establish advantages with respect to complications and cost, with equivalent cosmetic outcomes. Larger studies evaluating patient- or parent-reported satisfaction and optimal timing of intervention as well as heterogeneity in outcomes are indicated.

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Han Yan, Taylor J. Abel, Naif M. Alotaibi, Melanie Anderson, Toba N. Niazi, Alexander G. Weil, Aria Fallah, John H. Phillips, Christopher R. Forrest, Abhaya V. Kulkarni, James M. Drake and George M. Ibrahim

OBJECTIVE

Despite increasing adoption of endoscopic techniques for repair of nonsagittal single-suture craniosynostosis, the efficacy and safety of the procedure relative to established open approaches are unknown. In this systematic review the authors aimed to directly compare open surgical and endoscope-assisted techniques for the treatment of metopic, unilateral coronal, and lambdoid craniosynostosis, with an emphasis on quantitative reported outcomes.

METHODS

A literature search was performed in compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant articles were identified from 3 electronic databases (MEDLINE, EMBASE, and CENTRAL [Cochrane Central Register of Controlled Trials]) from their inception to August 2017. The quality of methodology and bias risk were assessed using the Effective Public Health Practice Project (EPHPP) Quality Assessment Tool for Quantitative Studies.

RESULTS

Of 316 screened records, 7 studies were included in a qualitative synthesis of the evidence, of which none were eligible for meta-analysis. These reported on 111 unique patients with metopic, 65 with unilateral coronal, and 12 with lambdoid craniosynostosis. For all suture types, 100 (53%) children underwent endoscope-assisted craniosynostosis surgery and 32 (47%) patients underwent open repair. These studies all suggest that blood loss, transfusion rate, operating time, and length of hospital stay were superior for endoscopically treated children. Although potentially comparable or better cosmetic outcomes are reported, the paucity of evidence and considerable variability in outcomes preclude meaningful conclusions.

CONCLUSIONS

Limited data comparing open and endoscopic treatments for metopic, unilateral coronal, and lambdoid synostosis suggest a benefit for endoscopic techniques with respect to blood loss, transfusion, length of stay, and operating time. This report highlights shortcomings in evidence and gaps in knowledge regarding endoscopic repair of nonsagittal single-suture craniosynostosis, emphasizing the need for further matched-control studies.