Fatih Bayrakli
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Fatih Bayrakli has a total of 40 co-authors. Here are the top co-authors by number of shared publications:
- Dilek Ince Gunal
Department of Neurology, School of Medicine, Marmara University, Basibuyuk Mah. Maltepe Başıbüyük Yolu Sok. No:9/2 Maltepe, 34854 İstanbul, Turkey
4 shared publications - Hatice Ömercikoğlu Özden
Department of Neurology, School of Medicine, Marmara University, Basibuyuk Mah. Maltepe Başıbüyük Yolu Sok. No:9/2 Maltepe, 34854 İstanbul, Turkey
4 shared publications - Murat Vural
Department of Neurosurgery, School of Medicine, Eskişehir Osmangazi University, 26040 Eskişehir, Turkey
4 shared publications - Nazlı Durmaz Çelik
Department of Neurology, School of Medicine, Eskişehir Osmangazi University, 26040 Eskişehir, Turkey
4 shared publications - Serhat Özkan
Department of Neurology, School of Medicine, Eskişehir Osmangazi University, 26040 Eskişehir, Turkey
4 shared publications - Fatma Şeyda Üstüner
Department of Neurology, School of Medicine, Marmara University, Basibuyuk Mah. Maltepe Başıbüyük Yolu Sok. No:9/2 Maltepe, 34854 İstanbul, Turkey
2 shared publications
Latest Publications
- Open Access
- 23 February 2026
- Published by MDPI AG in Diagnostics
- Vol. 16 (4) , 644
Retrospective Multicenter Analysis of Withdrawal Syndrome in Parkinson’s Disease Patients After Cessation of Deep Brain Stimulation
Background: Abrupt cessation of deep brain stimulation (DBS) in Parkinson’s disease (PD), most commonly due to implantable pulse generator (IPG) battery depletion, may lead to DBS withdrawal syndrome (DBS-WDS). However, withdrawal syndrome does not occur in all patients following stimulation cessation. Methods: We retrospectively analyzed 210 PD patients treated with DBS. Patients with documented stimulation cessation were evaluated for the presence of withdrawal syndrome based on established clinical criteria. Demographic, disease-related, and treatment characteristics were assessed, and descriptive analysis was conducted on severe cases requiring intensive care. Results: DBS battery shutdown occurred in 28 patients (13.3%). Most patients did not develop withdrawal syndrome and experienced only transient motor worsening. Severe DBS-WDS requiring intensive care was rare, occurring in only three patients (1.4%). Battery shutdown alone did not predict withdrawal, nor was preoperative levodopa equivalent daily dose associated with withdrawal risk. Conclusions: DBS battery shutdown is usually not accompanied by withdrawal syndrome, and severe DBS-WDS is uncommon. Proactive battery management may help to prevent this rare but serious complication.
- 23 February 2026
- Published by MDPI AG in Diagnostics
- Vol. 16 (4) , 644
Open AccessRetrospective Multicenter Analysis of Withdrawal Syndrome in Parkinson’s Disease Patients After Cessation of Deep Brain Stimulation
Background: Abrupt cessation of deep brain stimulation (DBS) in Parkinson’s disease (PD), most commonly due to implantable pulse generator (IPG) battery depletion, may lead to DBS withdrawal syndrome (DBS-WDS). However, withdrawal syndrome does not occur in all patients following stimulation cessation. Methods: We retrospectively analyzed 210 PD patients treated with DBS. Patients with documented stimulation cessation were evaluated for the presence of withdrawal syndrome based on established clinical criteria. Demographic, disease-related, and treatment characteristics were assessed, and descriptive analysis was conducted on severe cases requiring intensive care. Results: DBS battery shutdown occurred in 28 patients (13.3%). Most patients did not develop withdrawal syndrome and experienced only transient motor worsening. Severe DBS-WDS requiring intensive care was rare, occurring in only three patients (1.4%). Battery shutdown alone did not predict withdrawal, nor was preoperative levodopa equivalent daily dose associated with withdrawal risk. Conclusions: DBS battery shutdown is usually not accompanied by withdrawal syndrome, and severe DBS-WDS is uncommon. Proactive battery management may help to prevent this rare but serious complication.
- Open Access
- 23 January 2026
- Published by MDPI AG in Preprints.org
Retrospective Multicenter Analysis of Withdrawal Syndromes After Stimulator Cessation in Parkinson’s Disease Patients with Deep Brain Stimulation
Background: Abrupt cessation of deep brain stimulation (DBS) in Parkinson’s disease (PD), most commonly due to implantable pulse generator (IPG) depletion, may lead to DBS withdrawal syndrome (DBS-WDS). However, withdrawal does not occur in all patients following stimulation cessation.Methods: We retrospectively analyzed 210 PD patients treated with DBS. Patients with documented stimulation cessation were evaluated for the presence of withdrawal syndrome based on clinical criteria. Demographic, disease-related, and treatment characteristics were assessed, with descriptive analysis of severe cases requiring intensive care.Results: DBS battery shutdown occurred in 28 patients (13.3%). Most patients did not develop withdrawal syndrome and experienced only transient motor worsening. Severe DBS-WDS requiring intensive care was rare, occurring in only three patients (1.4%). Battery shutdown alone did not predict withdrawal, and preoperative levodopa equivalent daily dose was not associated with withdrawal risk.Conclusions: DBS battery shutdown is usually not accompanied by withdrawal syndrome, and severe DBS-WDS is uncommon. Proactive battery management may help prevent this rare but serious complication.
- 23 January 2026
- Published by MDPI AG in Preprints.org
Open AccessRetrospective Multicenter Analysis of Withdrawal Syndromes After Stimulator Cessation in Parkinson’s Disease Patients with Deep Brain Stimulation
Background: Abrupt cessation of deep brain stimulation (DBS) in Parkinson’s disease (PD), most commonly due to implantable pulse generator (IPG) depletion, may lead to DBS withdrawal syndrome (DBS-WDS). However, withdrawal does not occur in all patients following stimulation cessation.Methods: We retrospectively analyzed 210 PD patients treated with DBS. Patients with documented stimulation cessation were evaluated for the presence of withdrawal syndrome based on clinical criteria. Demographic, disease-related, and treatment characteristics were assessed, with descriptive analysis of severe cases requiring intensive care.Results: DBS battery shutdown occurred in 28 patients (13.3%). Most patients did not develop withdrawal syndrome and experienced only transient motor worsening. Severe DBS-WDS requiring intensive care was rare, occurring in only three patients (1.4%). Battery shutdown alone did not predict withdrawal, and preoperative levodopa equivalent daily dose was not associated with withdrawal risk.Conclusions: DBS battery shutdown is usually not accompanied by withdrawal syndrome, and severe DBS-WDS is uncommon. Proactive battery management may help prevent this rare but serious complication.
- Open Access
- 30 July 2025
- Published by MDPI AG in Journal of Clinical Medicine
- Vol. 14 (15) , 5382
Impact of Bilateral GPi Deep Brain Stimulation on Dystonia, Functional Outcomes, and Caregiver Burden in Patients with Dystonic Cerebral Palsy
Background: Dystonic cerebral palsy (DCP) is a complex, disabling manifestation of secondary dystonia, which significantly impacts motor function, quality of life, and well-being. Conventional pharmacologic therapies frequently do not relieve symptoms sufficiently. Deep brain stimulation (DBS) of the globus pallidus internal segment (GPi) has gained increasing attention as a neuromodulatory therapy for refractory dystonia. Still, the experience of the effect of GPi DBS treatment in adults with DCP has, until recently, been limited. Methods: We performed a retrospective, two-center case series of 11 adult patients with medically refractory DCP who underwent bilateral GPi-DBS. The clinical outcomes were evaluated based on the Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS), the Functional Independence Measure (FIM), the Gross Motor Function Classification System (GMFCS), and the Caregiver Burden Scale (CBS). The assessments were done preoperatively and at 1-year follow-up. Changes in continuous variables were analyzed using paired t-tests. Results: At the 1-year follow-up, the mean BFMDRS score improved from 69.6 ± 27.6 to 54.3 ± 36.5 (p = 0.001), indicating a significant reduction in overall dystonia severity. Functional independence also improved, demonstrated by the rise in FIM scores from 65.3 ± 33.9 to 79.2 ± 43.4 (p = 0.006). Although GMFCS levels did not change in most patients (p = 0.125), the burden on caregivers decreased significantly, with CBS scores falling from 35.7 ± 18.8 to 32.0 ± 17.1 (p = 0.015). There were no surgical complications. Conclusions: In adults, bilateral GPi-DBS is a safe and effective intervention for DCP, improving motor control and increasing functional independence while decreasing caregiver burden. These findings lend support to its role in the multidisciplinary management of DCP.
- 30 July 2025
- Published by MDPI AG in Journal of Clinical Medicine
- Vol. 14 (15) , 5382
Open AccessImpact of Bilateral GPi Deep Brain Stimulation on Dystonia, Functional Outcomes, and Caregiver Burden in Patients with Dystonic Cerebral Palsy
Background: Dystonic cerebral palsy (DCP) is a complex, disabling manifestation of secondary dystonia, which significantly impacts motor function, quality of life, and well-being. Conventional pharmacologic therapies frequently do not relieve symptoms sufficiently. Deep brain stimulation (DBS) of the globus pallidus internal segment (GPi) has gained increasing attention as a neuromodulatory therapy for refractory dystonia. Still, the experience of the effect of GPi DBS treatment in adults with DCP has, until recently, been limited. Methods: We performed a retrospective, two-center case series of 11 adult patients with medically refractory DCP who underwent bilateral GPi-DBS. The clinical outcomes were evaluated based on the Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS), the Functional Independence Measure (FIM), the Gross Motor Function Classification System (GMFCS), and the Caregiver Burden Scale (CBS). The assessments were done preoperatively and at 1-year follow-up. Changes in continuous variables were analyzed using paired t-tests. Results: At the 1-year follow-up, the mean BFMDRS score improved from 69.6 ± 27.6 to 54.3 ± 36.5 (p = 0.001), indicating a significant reduction in overall dystonia severity. Functional independence also improved, demonstrated by the rise in FIM scores from 65.3 ± 33.9 to 79.2 ± 43.4 (p = 0.006). Although GMFCS levels did not change in most patients (p = 0.125), the burden on caregivers decreased significantly, with CBS scores falling from 35.7 ± 18.8 to 32.0 ± 17.1 (p = 0.015). There were no surgical complications. Conclusions: In adults, bilateral GPi-DBS is a safe and effective intervention for DCP, improving motor control and increasing functional independence while decreasing caregiver burden. These findings lend support to its role in the multidisciplinary management of DCP.
- Open Access
- 20 May 2025
- Published by MDPI AG in Preprints.org
Impact of Bilateral GPi Deep Brain Stimulation on Dystonia, Functional Outcomes, and Caregiver Burden in Patients with Dystonic Cerebral Palsy
Background: Dystonic cerebral palsy (DCP) is a complex, disabling manifestation of secondary dystonia, which significantly impacts motor function, quality of life, and caregiver wellbeing. Conventional pharmacologic therapies frequently do not relieve symptoms sufficiently. Deep brain stimulation (DBS) of the globus pallidus internal segment (GPi) has garnered increasing attention as a neuromodulatory treatment for refractory dystonia. Still, the experience in the effect of Gpi DBS treatment in adults with DCP has, until recently, been limited. Methods: We performed a retrospective, two-center case series of 11 adult patients with medically refractory DCP who underwent bilateral GPi-DBS. The clinical outcomes were evaluated based on the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS), the Functional İndependence Measure (FIM), the Gross Motor Function Classification System (GMFCS), and the Caregiver Burden Scale (CBS. The assessments were done preoperatively and at 1-year follow-up. Changes in continuous variables were analyzed using paired t-tests. Results: At the 1-year follow-up, the mean BFMDRS score improved from 69.6 ± 27.6 to 54.3 ± 36.5 (p = 0.001), significantly reducing overall dystonia severity. Functional independence also improved, demonstrated by the rise in FIM scores from 65.3 ± 33.9 to 79.2 ± 43.4 (p = 0.006). Although GMFCS levels did not change in most patients (p = 0.125), the burden on caregivers reduced significantly, with CBS scores falling from 35.7 ± 18.8 to 32.0 ± 17.1 (p = 0.015). There were no surgical complications. Conclusion: In adults, DCP, bilateral GPi-DBS is a safe and effective intervention that improves motor control and increases functional independence with decreased caregiver burden. These findings lend support to its role in the multidisciplinary management of DCP.
- 20 May 2025
- Published by MDPI AG in Preprints.org
Open AccessImpact of Bilateral GPi Deep Brain Stimulation on Dystonia, Functional Outcomes, and Caregiver Burden in Patients with Dystonic Cerebral Palsy
Background: Dystonic cerebral palsy (DCP) is a complex, disabling manifestation of secondary dystonia, which significantly impacts motor function, quality of life, and caregiver wellbeing. Conventional pharmacologic therapies frequently do not relieve symptoms sufficiently. Deep brain stimulation (DBS) of the globus pallidus internal segment (GPi) has garnered increasing attention as a neuromodulatory treatment for refractory dystonia. Still, the experience in the effect of Gpi DBS treatment in adults with DCP has, until recently, been limited. Methods: We performed a retrospective, two-center case series of 11 adult patients with medically refractory DCP who underwent bilateral GPi-DBS. The clinical outcomes were evaluated based on the Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS), the Functional İndependence Measure (FIM), the Gross Motor Function Classification System (GMFCS), and the Caregiver Burden Scale (CBS. The assessments were done preoperatively and at 1-year follow-up. Changes in continuous variables were analyzed using paired t-tests. Results: At the 1-year follow-up, the mean BFMDRS score improved from 69.6 ± 27.6 to 54.3 ± 36.5 (p = 0.001), significantly reducing overall dystonia severity. Functional independence also improved, demonstrated by the rise in FIM scores from 65.3 ± 33.9 to 79.2 ± 43.4 (p = 0.006). Although GMFCS levels did not change in most patients (p = 0.125), the burden on caregivers reduced significantly, with CBS scores falling from 35.7 ± 18.8 to 32.0 ± 17.1 (p = 0.015). There were no surgical complications. Conclusion: In adults, DCP, bilateral GPi-DBS is a safe and effective intervention that improves motor control and increases functional independence with decreased caregiver burden. These findings lend support to its role in the multidisciplinary management of DCP.
- 22 April 2019
- Published by Taylor & Francis in British Journal Of Neurosurgery
- Vol. 37 (4) , 728-730
Low grade oligodendroglioma seeding around the 4th ventricle
We report a 45 years old female patient with a left temporal grade II oligodendroglioma that recurred on the wall of the fourth ventricle at grade II oligodendroglioma.
- 22 April 2019
- Published by Taylor & Francis in British Journal Of Neurosurgery
- Vol. 37 (4) , 728-730
Low grade oligodendroglioma seeding around the 4th ventricle
We report a 45 years old female patient with a left temporal grade II oligodendroglioma that recurred on the wall of the fourth ventricle at grade II oligodendroglioma.
- 1 January 2019
- Published by Turkish Neurosurgical Society in Turkish Neurosurgery
- Vol. 30 (3) , 428-433
Analyses of copy number variations in myxopapillary ependymomas of cauda equina
AIM: To identify the copy number variations that are specific to myxopapillary ependymomas (MPEs) of the cauda equina. MATERIAL and METHODS: The patient cohort included five patients who underwent resection of histologically confirmed MPEs. Tumor samples collected during surgery and stored in liquid nitrogen as well as corresponding blood samples collected were analyzed. Genomic DNA from the venous blood and tumor samples was obtained using standard techniques and hybridized to a Cytoscan 750K Array in accordance with the manufacturer's introductions. RESULTS: As a novel finding, amplification on chromosome 14q32.33 was detected in all tumor and blood samples, except one tumor sample. All tumor tissues also showed amplification on chromosomes 5, 7, 9, and 16. CONCLUSION: Although further studies with larger cohorts are required to identify genes involved in MPE tumorigenesis and to validate our results, these findings provide a basis for advanced molecular biological and genetic studies of MPEs.
- 1 January 2019
- Published by Turkish Neurosurgical Society in Turkish Neurosurgery
- Vol. 30 (3) , 428-433
Analyses of copy number variations in myxopapillary ependymomas of cauda equina
AIM: To identify the copy number variations that are specific to myxopapillary ependymomas (MPEs) of the cauda equina. MATERIAL and METHODS: The patient cohort included five patients who underwent resection of histologically confirmed MPEs. Tumor samples collected during surgery and stored in liquid nitrogen as well as corresponding blood samples collected were analyzed. Genomic DNA from the venous blood and tumor samples was obtained using standard techniques and hybridized to a Cytoscan 750K Array in accordance with the manufacturer's introductions. RESULTS: As a novel finding, amplification on chromosome 14q32.33 was detected in all tumor and blood samples, except one tumor sample. All tumor tissues also showed amplification on chromosomes 5, 7, 9, and 16. CONCLUSION: Although further studies with larger cohorts are required to identify genes involved in MPE tumorigenesis and to validate our results, these findings provide a basis for advanced molecular biological and genetic studies of MPEs.
- 26 May 2015
- Published by Springer Nature in Child's Nervous System
- Vol. 31 (8) , 1367-1370
Neural tube defect family with recessive trait linked to chromosome 9q21.12-21.31
Meningomyelocele is one of the most common and socioeconomically, psychologically, and physically debilitating neurodevelopmental diseases. A few chromosomal locus and genes have been identified as responsible for the disease; however, clear evidence still needs to be produced. This study aimed to show evidence of a strong genetic linkage in a novel chromosomal locus in a family with this neural tube defect. We identified a neural tube defect family in eastern Turkey, where two of six offspring had operations due to thoracolumbar meningomyelocele. The parents were of a consanguineous marriage. We collected venous blood from six offspring of the family. Whole genome linkage analysis was performed in all offspring. A theoretical maximum logarithm of an odds score of 3.16 was identified on chromosome 9q21.12-21.31. This result shows a strong genetic linkage to this locus. Our results identified a novel chromosomal locus related to meningomyelocele and provide a base for further investigations toward the discovery of a new causative gene.
- 26 May 2015
- Published by Springer Nature in Child's Nervous System
- Vol. 31 (8) , 1367-1370
Neural tube defect family with recessive trait linked to chromosome 9q21.12-21.31
Meningomyelocele is one of the most common and socioeconomically, psychologically, and physically debilitating neurodevelopmental diseases. A few chromosomal locus and genes have been identified as responsible for the disease; however, clear evidence still needs to be produced. This study aimed to show evidence of a strong genetic linkage in a novel chromosomal locus in a family with this neural tube defect. We identified a neural tube defect family in eastern Turkey, where two of six offspring had operations due to thoracolumbar meningomyelocele. The parents were of a consanguineous marriage. We collected venous blood from six offspring of the family. Whole genome linkage analysis was performed in all offspring. A theoretical maximum logarithm of an odds score of 3.16 was identified on chromosome 9q21.12-21.31. This result shows a strong genetic linkage to this locus. Our results identified a novel chromosomal locus related to meningomyelocele and provide a base for further investigations toward the discovery of a new causative gene.
- Open Access
- 1 January 2013
- Published by Springer Nature in BMC Genetics
- Vol. 14 (1) , 95
Mutation in MEOX1 gene causes a recessive Klippel-Feil syndrome subtype
Klippel-Feil syndrome (KFS) is characterized by the developmental failure of the cervical spine and has two dominantly inherited subtypes. Affected individuals who are the children of a consanguineous marriage are extremely rare in the medical literature, but the gene responsible for this recessive trait subtype of KFS has recently been reported.
- 1 January 2013
- Published by Springer Nature in BMC Genetics
- Vol. 14 (1) , 95
Open AccessMutation in MEOX1 gene causes a recessive Klippel-Feil syndrome subtype
Klippel-Feil syndrome (KFS) is characterized by the developmental failure of the cervical spine and has two dominantly inherited subtypes. Affected individuals who are the children of a consanguineous marriage are extremely rare in the medical literature, but the gene responsible for this recessive trait subtype of KFS has recently been reported.