Papers by Christos Profyris
Neuro-oncology, Sep 1, 2021
medRxiv (Cold Spring Harbor Laboratory), Jul 30, 2021
The human brain is a highly plastic 'complex' network -it is highly resilient to damage and capab... more The human brain is a highly plastic 'complex' network -it is highly resilient to damage and capable of self-reorganisation after a large perturbation. Clinically, neurological deficits secondary to iatrogenic injury have very few active treatments. New imaging and stimulation technologies, though, offer promising therapeutic avenues to accelerate post-operative recovery trajectories. In this study, we sought to establish the safety profile for 'interventional neurorehabilitation': connectome-based therapeutic brain stimulation to drive cortical reorganisation and promote functional recovery post-craniotomy. In n=34 glioma patients who experienced post-operative motor or language deficits, we used connectomics to construct single-subject cortical networks. Based on their clinical and connectivity deficit, patients underwent network-specific Transcranial Magnetic Stimulation (TMS) sessions daily over five consecutive days. Patients were then assessed for TMS-related side effects and improvements. Results: 31/34 (91%) patients were successfully recruited and enrolled for TMS treatment within two weeks of glioma surgery. No seizures or serious complications occurred during TMS rehabilitation and one-week post-stimulation. Transient headaches were reported in 4/31 patients but improved after a single session. No neurological worsening was observed while a benefit was noted in 28/31 patients post-TMS. We present two clinical vignettes and a video demonstration of interventional neurorehabilitation. For the first time, we demonstrate the safety profile and ability to recruit, enrol, and complete TMS acutely post-craniotomy in a high seizure risk population. Given the lack of randomisation and controls in this study, prospective randomised sham-controlled stimulation trials are now warranted to establish the efficacy of interventional neurorehabilitation following craniotomy.
Journal of The American Academy of Dermatology, 2012
Expert Opinion on Pharmacotherapy, Jul 19, 2019
Introduction: Atypical meningiomas are aggressive tumors associated with high rates of recurrence... more Introduction: Atypical meningiomas are aggressive tumors associated with high rates of recurrence and mortality. Current therapy is surgical resection followed by radiotherapy which has reasonable success rates. However, there are cases where surgical resection is not possible, and radiotherapy is not advisable. Areas covered: In this short review, the authors have searched the current literature for explorations of adjuvant treatments such as chemotherapy and pharmaceutical agents. Most current chemotherapeutic agents have been unsuccessful in producing radiographic reduction or disease stabilization, although drugs like somatostatin analogs and plantderived chemotherapeutics have shown some promise. The authors note that most of the studies in this field have been case series with a few randomized trials present. This makes it hard to ascertain the effectiveness of the drugs and so further research is required in the field. Expert opinion: Finding pharmacotherapies to combat atypical meningiomas needs Big data genomic analysis. This will assist in generating drug candidates and a multidrug approach to therapy that will exploit several of the pathological pathways of atypical meningiomas. Using multidrug therapy that affects several pathways also addresses the issue of meningioma heterogeneity and adaptability.
World Neurosurgery, Jun 1, 2021
BACKGROUND Surgical resection of symptomatic pineal cysts without hydrocephalus remains controver... more BACKGROUND Surgical resection of symptomatic pineal cysts without hydrocephalus remains controversial because patients can present with variable symptoms. Hesitancies in surgical decision making include determining surgical candidacy and whether results would be durable. METHODS We performed a retrospective analysis on patients who underwent resection of their pineal cysts in our practice. We examined the presenting symptomology and investigated the radiographic changes to the morphology of the cerebral aqueduct found on follow-up imaging. We examined the clinical outcomes and complications following surgical resection of symptomatic pineal cysts. RESULTS A total of 97 patients underwent resection of pineal cysts, with 84 patients that had adequate follow-up (mean 30.5 months). The patient population were predominantly female (76%) presenting at a mean of 24 years of age. Almost half of the patients had headaches that were positional, with 82% being bilateral. 39% and 19% of patients presented with photophobia and sonophobia, respectively, concurrent with their headaches. Many patients presented with visual disturbance (73%) along with other non-headache symptoms. Surgery resulted in 89% of patients with clinical improvements of their headaches. CONCLUSION Pineal cysts can present with variable headache symptomatology. Surgical resection of pineal cysts in carefully selected symptomatic patients after exhaustive conservative management can be performed safely and result in durable symptomatic relief.
This study reports on 24 Myelomeningocoeles (MMC) repaired at Chris Hani Baragwanath Hospital by ... more This study reports on 24 Myelomeningocoeles (MMC) repaired at Chris Hani Baragwanath Hospital by a single surgeon. Mean gestation was 38.13 weeks, most MMCs were in the lumbosacral region and mean MMC surface area was 19.4cm 2 . Cerebrospinal Fluid (CSF) leak at birth was present in 50%, lower-limb neurology in 71%, lower cranial nerve dysfunction in 13% and hydrocephalus in 54%. Clubfoot was present in 71%, congenital hip dysplasia in 24%, neurogenic bladder in 82% and cutaneous abnormalities in 12%. Mean time from birth to MMC repair was 13.6 days, 46% of infants had ventriculoperitoneal shunt insertion and latex allergy was absent. Complication wise, wound dehiscence arose in 21%, CSF leak in 12.5% and infection in 25%. Neonates with CSF leak subsequently developed both wound dehiscence and CSF infection.
Surgical Neurology International
Background: Osseous hyperpigmentation of the calvarium is an extremely rare finding with only few... more Background: Osseous hyperpigmentation of the calvarium is an extremely rare finding with only few reported cases in literature. Case Description: The case is of a 59-year-old Caucasian male who presented with an acute history of generalized tonic clonic seizures and progressive weakness of the right upper limb. He had a background history of a malignant melanoma which had been resected from his left external acoustic meatus 4 weeks prior. Neuroimaging of the brain showed an intra-axial space-occupying lesion in his left parietal lobe with no associated osseous changes. A left mini parietal craniotomy was performed which revealed black discoloration of the parietal bone. The lesion was successfully resected and the bone flap was secured back in place. The patient was discharged on the 4th day postoperatively with no complications. The unusual finding of black discoloration of the calvarium was found to be secondary to adolescent tetracycline use. Conclusion: Calvarial hyperpigmentati...
Journal of Medical Case Reports
Background Paragangliomas are rare neuroendocrine tumors. While paragangliomas of the spine are r... more Background Paragangliomas are rare neuroendocrine tumors. While paragangliomas of the spine are rare, those located in non-cauda equina areas with spinal canal extension are even rarer. Case presentation We present a case of a 23-year-old female of African descent with a primary thoracic paraganglioma with intervertebral extension resulting in displacement and compression of the spinal cord and extensive local invasion of the surrounding structures. This paraganglioma was functional with typical symptoms of catecholamine excess. Despite the aggressive nature of the paraganglioma, the patient only had isolated sensory symptoms in the left shoulder. Adequate alpha and beta-blockade were instituted prior to her undergoing surgery with near-total resection and complete preserved neurology. There was no underlying pathogenic genetic mutation found. Conclusions Even though rare, paraganglioma should be considered in the differential diagnosis of spinal tumors. Genetic testing should be pe...
Clinical Neurology and Neurosurgery
Scientific Reports
The human brain is a highly plastic ‘complex’ network—it is highly resilient to damage and capabl... more The human brain is a highly plastic ‘complex’ network—it is highly resilient to damage and capable of self-reorganisation after a large perturbation. Clinically, neurological deficits secondary to iatrogenic injury have very few active treatments. New imaging and stimulation technologies, though, offer promising therapeutic avenues to accelerate post-operative recovery trajectories. In this study, we sought to establish the safety profile for ‘interventional neurorehabilitation’: connectome-based therapeutic brain stimulation to drive cortical reorganisation and promote functional recovery post-craniotomy. In n = 34 glioma patients who experienced post-operative motor or language deficits, we used connectomics to construct single-subject cortical networks. Based on their clinical and connectivity deficit, patients underwent network-specific transcranial magnetic stimulation (TMS) sessions daily over five consecutive days. Patients were then assessed for TMS-related side effects and ...
Trauma Case Reports, 2022
Superficial temporal artery (STA) pseudoaneurysm is a very rare occurrence that usually presents ... more Superficial temporal artery (STA) pseudoaneurysm is a very rare occurrence that usually presents as a pulsatile mass along the STA distribution following trauma or an iatrogenic cause. We report a case of STA pseudoaneurysm that developed in a 32 year old male following blunt trauma. Unfortunately, the pseudoaneurysm was missed and led to multiple hospital presentations that culminated in an acute bleeding episode. Surgical resection of the pseudoaneurysm was performed and the STA was reconstructed with an STA-STA anastomosis. To our knowledge, this is the second reported case of an STA pseudoaneurysm treated with an STA-STA anastomosis. This case report aims to bring awareness. Although extremely rare, the importance of treating the presence of a pulsatile mass along the STA distribution following a history of trauma or recent cranial surgery with a high level of suspicion is imperative.
World Neurosurgery, 2021
BACKGROUND Surgical resection of symptomatic pineal cysts without hydrocephalus remains controver... more BACKGROUND Surgical resection of symptomatic pineal cysts without hydrocephalus remains controversial because patients can present with variable symptoms. Hesitancies in surgical decision making include determining surgical candidacy and whether results would be durable. METHODS We performed a retrospective analysis on patients who underwent resection of their pineal cysts in our practice. We examined the presenting symptomology and investigated the radiographic changes to the morphology of the cerebral aqueduct found on follow-up imaging. We examined the clinical outcomes and complications following surgical resection of symptomatic pineal cysts. RESULTS A total of 97 patients underwent resection of pineal cysts, with 84 patients that had adequate follow-up (mean 30.5 months). The patient population were predominantly female (76%) presenting at a mean of 24 years of age. Almost half of the patients had headaches that were positional, with 82% being bilateral. 39% and 19% of patients presented with photophobia and sonophobia, respectively, concurrent with their headaches. Many patients presented with visual disturbance (73%) along with other non-headache symptoms. Surgery resulted in 89% of patients with clinical improvements of their headaches. CONCLUSION Pineal cysts can present with variable headache symptomatology. Surgical resection of pineal cysts in carefully selected symptomatic patients after exhaustive conservative management can be performed safely and result in durable symptomatic relief.
ABSTRACTPurposeThe human brain is a highly plastic ‘complex’ network –it is highly resilient to d... more ABSTRACTPurposeThe human brain is a highly plastic ‘complex’ network –it is highly resilient to damage and capable of self-reorganisation after a large perturbation. Clinically, neurological deficits secondary to iatrogenic injury have very few active treatments. New imaging and stimulation technologies, though, offer promising therapeutic avenues to accelerate post-operative recovery trajectories. In this study, we sought to establish the safety profile for ‘interventional neurorehabilitation’: connectome-based therapeutic brain stimulation to drive cortical reorganisation and promote functional recovery post-craniotomy.MethodsIn n=34 glioma patients who experienced post-operative motor or language deficits, we used connectomics to construct single-subject cortical networks. Based on their clinical and connectivity deficit, patients underwent network-specific Transcranial Magnetic Stimulation (TMS) sessions daily over five consecutive days. Patients were then assessed for TMS-relat...
Neuro-Oncology, 2021
INTRODUCTION The human brain is a highly neuroplastic ‘complex’ network: it self-organises withou... more INTRODUCTION The human brain is a highly neuroplastic ‘complex’ network: it self-organises without a hard blueprint, adapts to evolving circumstances, and can withstand insults. However, similar to other naturally occurring networks, brain networks can only endure a finite amount of damage before cognitive processes are affected. In this study, we first sought to establish the brain networks governing domain-general cognition (DGC) in healthy individuals across the lifespan. We then sought to map, track, and potentially rehabilitate networks governing DGC through connectomics and non-invasive brain stimulation (NIBS) when damaged by low-grade gliomas (LGG) and surgical oncology. METHODS Using MRI and cognitive data from n=629 individuals (aged 18–88, Female= 51%), we assessed the structural, functional, and topological relevance of the spatially-distributed multiple-demand (MD) system for DGC. Next, in n=17 patients undergoing glioma surgery, we longitudinally acquired connectomic a...
Clinical Neurology and Neurosurgery, 2021
BACKGROUND Current anaplastic oligodendroglioma (AO) management strategies involve surgical resec... more BACKGROUND Current anaplastic oligodendroglioma (AO) management strategies involve surgical resection followed by adjuvant radiotherapy and/or chemotherapy. We investigated a subset of patients at our institution with AO, who, based on their treatment preferences, received surgery without any form of adjuvant therapy. This subset of patients was compared to a cohort with AO who received adjuvant therapy in order to investigate any differences in clinical and survival outcomes. METHODS A retrospective review of all AO patients treated by the senior author was undertaken between 1994 and 2018. A total of thirty-three cases were identified. Eleven had surgery alone, and twenty-two had surgery with adjuvant therapy. Progression free (PFS) and overall survival (OS) were compared between cohorts and potential confounders were addressed. RESULTS Gross total resection was achieved in 29 patients, and near total resection in 4 patients. PFS was not statistically different between patients treated with surgery alone versus patients receiving surgery plus adjuvant therapy (surgery alone: 84 ± 16 months; surgery with radiotherapy: 60 ± 9 months; p = 0.08). In addition, OS was also not statistically different between these groups (surgery alone: 215 ± 17 months; surgery with therapy: 241 ± 22 months; p = 0.44). CONCLUSIONS It is reasonable to consider a "watch and monitor" surveillance strategy in patients who decline adjuvant radiotherapy following surgical resection of their AO. Patients should be made aware that this treatment plan is not standard within current models of care for AO.
Expert Opinion on Pharmacotherapy, 2019
Introduction: Atypical meningiomas are aggressive tumors associated with high rates of recurrence... more Introduction: Atypical meningiomas are aggressive tumors associated with high rates of recurrence and mortality. Current therapy is surgical resection followed by radiotherapy which has reasonable success rates. However, there are cases where surgical resection is not possible, and radiotherapy is not advisable. Areas covered: In this short review, the authors have searched the current literature for explorations of adjuvant treatments such as chemotherapy and pharmaceutical agents. Most current chemotherapeutic agents have been unsuccessful in producing radiographic reduction or disease stabilization, although drugs like somatostatin analogs and plantderived chemotherapeutics have shown some promise. The authors note that most of the studies in this field have been case series with a few randomized trials present. This makes it hard to ascertain the effectiveness of the drugs and so further research is required in the field. Expert opinion: Finding pharmacotherapies to combat atypical meningiomas needs Big data genomic analysis. This will assist in generating drug candidates and a multidrug approach to therapy that will exploit several of the pathological pathways of atypical meningiomas. Using multidrug therapy that affects several pathways also addresses the issue of meningioma heterogeneity and adaptability.
Journal of Neurodegeneration Regeneration, 2008
Neurotoxicity Research, 2005
The mechanisms determining the fate of Schwann cells during disease and injury of the adult mamma... more The mechanisms determining the fate of Schwann cells during disease and injury of the adult mammalian peripheral nervous system (PNS) are becoming defined by current advances in molecular neurobiology. It is now apparent that the molecular pathways which regulate the production of the mature myelinating Schwann cell during development may also apply to degenerative and regenerative mechanisms following PNS disease. This review outlines neurobiological responses of Schwann cells during development, injury and disease in order to define the molecular pathways which regulate these crucial events. These mechanisms have implications for our attempts to intervene pharmacologically during pathologies of the PNS.
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Papers by Christos Profyris