Ahmad Tamimi - Academia.edu (original) (raw)
Papers by Ahmad Tamimi
American Journal of Case Reports, Feb 8, 2021
IntechOpen eBooks, Oct 12, 2022
Pediatric Neurosurgery, 2021
Introduction: There is paucity of data regarding change in arachnoid cyst (AC) volume following s... more Introduction: There is paucity of data regarding change in arachnoid cyst (AC) volume following surgery. This study aimed at investigating the clinical outcome of ACs and applying 2 volumetric methods for determination of their volume change post microsurgical fenestration. Methods: Twenty-one ACs in 20 patients that underwent microsurgical fenestration were analyzed using 2 volumetric methods; the modified McDonald equation and the picture archiving and communication (PAC) system-based method. Patients were followed up for 23 ± 40.3 months. Results: The majority of the patients (13 or 65%) were children. Preoperative symptoms in children were mainly seizures and less commonly headache. Of the 20 patients, 12 (60%) had complete resolution of their preoperative symptoms with 8 (40.0%) showing partial improvement. Volumetric studies showed a mean reduction in AC size of 73.7% in children and 64.4% in adults using the PAC system versus 67.9% in children and 70.5% in adults using the mo...
Advances in Electroencephalography and Brain Connectome
The method of electroencephalography is an accurate and objective method of recording the bioelec... more The method of electroencephalography is an accurate and objective method of recording the bioelectrical activity of the brain, used both in scientific research and in clinical practice. However, achieving a high-quality result requires a lot of preparatory work. This chapter describes the technology for conducting electroencephalographic studies, their subsequent analysis, and presentation of results that are understandable to both a specialist neurophysiologist and a practicing neurologist. You will also find a description of the organization of the EEG study, the choice of scenario, functional tests, and the basics of forming a medical report. We will also consider individual issues of organizing an EEG study in people who have had a stroke, and multichannel and functional EEG studies.
Jordan Medical Journal
Background: Melanocytoma is a rare pigmented central nervous tumor. In the spine, it may develop ... more Background: Melanocytoma is a rare pigmented central nervous tumor. In the spine, it may develop in meninges, extramedullary or intramedullary. It usually has good outcome after total excision. Case report: A 40-year-old male patient was admitted to our hospital 12 years ago with a 3-month history of progressive neck pain and difficulty walking. On clinical examination, he showed upper dorsal bilateral gray blue hyperpigmentation, quadriparesis and bilateral hypoesthesia below C4. Cervical magnetic resonance imaging (MRI) T1-weighted images without contrast showed a C3-C4 intradural, extramedullary lesion. The patient underwent total microsurgical resection of the lesion. Histological and immunohistochemical analyses confirmed the diagnosis of melanocytoma. Another skin biopsy of the abnormal area showed histological findings of a blue skin nevus. Eight years after resection the patient presented with recurrent symptoms, which were similar to his initial presentation. Cervical MRI s...
BMC Medical Education
Background Different variables have been used to predict the academic performance of students in ... more Background Different variables have been used to predict the academic performance of students in medical schools. The aim of this study was to assess the effect of demographics, admission system, and high-school background on the academic performance of medical students. Methods We conducted this longitudinal cohort study on 808 students admitted to the Faculty of. Medicine at the University of Jordan (Amman, Jordan), in the years 2012 and 2013. Admission pathway, and academic performance data were collected and analyzed. Results A total of 808 students [i.e., 426 (52.7%) females, and 382(47.3%) males] were identified. Admitted students were holding 17 different types of high school degrees, and were accepted through 6 different quota pathways (open competition [National unified admission], underprivileged [“Makrumah”], parallel, children of university staff, international students, and others). Students admitted through the open competition and the underprivileged quota(Makrumah) w...
Scientific Reports
Given the massive use of facemasks (FMs) during the covid-19 pandemic, concerns have been raised ... more Given the massive use of facemasks (FMs) during the covid-19 pandemic, concerns have been raised regarding the effect of FMs wearing on overall health. This study aimed at evaluating the effect of surgical FM on brain neuro-electrical activity. Electroencephalography (EEG) background frequency (BGF) and background amplitude (BGA) was performed on 30 volunteers before (baseline), during and after wearing a FM for 60 min. Measurements were done during normal ventilation, hyperventilation and post-hyperventilation (PHVR). Blood gas levels were assessed at baseline and after FM use. EEG analysis concerning baseline (without FM) (BGA), was 47.69 ± 18.60 µV, wearing FM, BGA was 48.45 ± 17.79 µV, post FM use BGA was 48.08 ± 18.30 µV. There were no statistically significant differences between baseline BGA and BGA under FM and post FM. BGF, Baseline data were 10.27 ± 0.79, FM use 10.30 ± 0.76 and post FM use was 10.33 ± 0.76. There were no statistically significant differences between basel...
Materials Science Forum, 2016
One of the key factors that play an important role in the performance of a solid propellant rocke... more One of the key factors that play an important role in the performance of a solid propellant rocket is dependent on its burning rate. A strand burner is a type of apparatus used to measure the propellant burning rate at elevated pressure. This study investigates the relation between burning rates of aluminized ammonium perchlorate at low pressure. Chamber pressure was varied from 1 atm, 3 atm, 5 atm and 7 atm. This study shows that propellant burning rate is about 50%-62% higher when the burn rate test is conducted at atmospheric condition compared to when it is done in inert gas. The investigation’s results also revealed an increasing propellant burning rate when the chamber pressure is increased. In conclusion, the burning condition and chamber pressure influences the propellant burning rate.
Journal of Musculoskeletal & Neuronal Interactions, 2021
Objectives: To investigate the effect of vagus nerve stimulation (VNS) on the bone mineral densit... more Objectives: To investigate the effect of vagus nerve stimulation (VNS) on the bone mineral density (BMD) in epileptic patients. Methods: A prospective cohort study was conducted on individuals with refractory seizures who underwent VNS surgery between January 2012 and December 2018. BMD was measured preoperatively and between 6 months and one year after surgery. Results: Twenty-one patients (mean age (±SD)=23.6±12.3 years) were recruited for the implantation of a VNS device. The mean absolute increase in lumbar BMD in the 21 patients was 0.04±0.04 g/cm2 resulting in an overall percent increase from baseline of 4.7±6.1%. BMD increased by an amount ≥ the least significant change (LSC) for the lumbar spine in 13 patients (61.9%). The lumbar Z score also increased in these patients from -1.22±1.15 to -0.88±1.22, P=0.006). Pre and Post VNA femoral BMD was measured in only 11 patients and, of those 3 showed a significant increase in BMD, 1 a significant decrease and 7 no change. Conclusio...
Glioblastoma
Glioblastoma (GBM) is the most aggressive malignant primary brain tumor. With an incidence rate o... more Glioblastoma (GBM) is the most aggressive malignant primary brain tumor. With an incidence rate of 3.19 per 100,000 persons in the United States and a median age of 64 years, it is uncommon in children. The incidence is 1.6 times higher in males compared to females and 2.0 times higher in Caucasians compared to Africans and Afro-Americans, with lower incidence in Asians and American Indians. GBM is commonly located in the supratentorial region (frontal, temporal, parietal, and occipital lobes) and is rarely located in cerebellum. Genetic and environmental factors have been investigated in GBM. Risk factors include prior radiotherapy, decreased susceptibility to allergy, immune factors and immune genes, as well as some single nucleotide polymorphisms detected by genomic analysis. Use of anti-inflammatory medication has been found to be protective against GBM. Survival from GBM is poor; only few patients survive 2.5 years and less than 5% of patients survive 5 years following diagnosis. Survival rates for patients with GBM have shown no notable improvement in population statistics in the last three decades. Molecular epidemiology integrates molecular technology into epidemiological studies and outcomes. The future of the epidemiology of Epidemiology of Glioblastoma 144 GBM will depend on multicenter studies generating large clinical data sets of genomic data potentially leading to further understanding of the roles of genes and environment in the development of this devastating disease.
Middle East Journal of Anaesthesiology, Feb 1, 2009
Objective: Electrocorticography (ECoG) may be used to guide epilepsy surgery. However, anesthetic... more Objective: Electrocorticography (ECoG) may be used to guide epilepsy surgery. However, anesthetics can suppress epileptiform activity or induce confounding burst-suppression patterns and the relationship between ECoG results and seizure outcome is controversial. In this study, we evaluated the ECoG activity under several different anesthetics and examined the relationship between ECoG and outcome. Methods: We retrospectively studied 44 patients who had ECoG during epilepsy surgery. Anesthesia was with fentanyl and isoflurane (n = 19), fentanyl and sevoflurane (n = 9), remifentanil and sevoflurane (n = 5), remifentanil and propofol (n = 9), and fentanyl with propofol sedation during local anesthesia (n = 2). Pre-resection ECoG was considered satisfactory if epileptiform activity was present and there was no burst-suppression. Post-resection ECoG was graded according to residual epileptiform activity: A (none), B (mild), C (moderate). Seizure outcome was graded: I (seizure free without medication), II (seizure free with medication), III (> 50% seizure reduction) or IV (< 50% seizure reduction). Grades I-III were considered beneficial. Results: ECoG was satisfactory in 43 of the 44 surgeries, but one of the 11 recordings during propofol showed no epileptiform activity. Thirty-six of 37 patients (97%) with ECoG grade A or B and five of seven patients (71%) with ECoG grade C benefited from epilepsy surgery. Chi-squared, p > 0.05. Conclusions: Satisfactory ECoG is possible using isoflurane or sevoflurane with nitrous oxide and fentanyl or remifentanil or using propofol and remifentanil. However, one of eleven ECoGs under propofol was negative for epileptiform activity. The amount of post-resection ECoG epileptiform activity does not significantly correlate with seizure outcome.
Neurosciences, Oct 1, 2010
Secondary aneurysmal bone cyst in fibrous dysplasia is exceedingly rare, especially in the skull ... more Secondary aneurysmal bone cyst in fibrous dysplasia is exceedingly rare, especially in the skull and particularly in the frontal bone. We present a case of aneurysmal bone cyst concomitant with fibrous dysplasia in the frontal bone in a 15-year-old male patient presenting with headache and euphoria with an uncharacteristic imaging appearance and treated successfully by total resection.
Textbook of Epilepsy Surgery, 2008
American Journal of Case Reports, Feb 8, 2021
IntechOpen eBooks, Oct 12, 2022
Pediatric Neurosurgery, 2021
Introduction: There is paucity of data regarding change in arachnoid cyst (AC) volume following s... more Introduction: There is paucity of data regarding change in arachnoid cyst (AC) volume following surgery. This study aimed at investigating the clinical outcome of ACs and applying 2 volumetric methods for determination of their volume change post microsurgical fenestration. Methods: Twenty-one ACs in 20 patients that underwent microsurgical fenestration were analyzed using 2 volumetric methods; the modified McDonald equation and the picture archiving and communication (PAC) system-based method. Patients were followed up for 23 ± 40.3 months. Results: The majority of the patients (13 or 65%) were children. Preoperative symptoms in children were mainly seizures and less commonly headache. Of the 20 patients, 12 (60%) had complete resolution of their preoperative symptoms with 8 (40.0%) showing partial improvement. Volumetric studies showed a mean reduction in AC size of 73.7% in children and 64.4% in adults using the PAC system versus 67.9% in children and 70.5% in adults using the mo...
Advances in Electroencephalography and Brain Connectome
The method of electroencephalography is an accurate and objective method of recording the bioelec... more The method of electroencephalography is an accurate and objective method of recording the bioelectrical activity of the brain, used both in scientific research and in clinical practice. However, achieving a high-quality result requires a lot of preparatory work. This chapter describes the technology for conducting electroencephalographic studies, their subsequent analysis, and presentation of results that are understandable to both a specialist neurophysiologist and a practicing neurologist. You will also find a description of the organization of the EEG study, the choice of scenario, functional tests, and the basics of forming a medical report. We will also consider individual issues of organizing an EEG study in people who have had a stroke, and multichannel and functional EEG studies.
Jordan Medical Journal
Background: Melanocytoma is a rare pigmented central nervous tumor. In the spine, it may develop ... more Background: Melanocytoma is a rare pigmented central nervous tumor. In the spine, it may develop in meninges, extramedullary or intramedullary. It usually has good outcome after total excision. Case report: A 40-year-old male patient was admitted to our hospital 12 years ago with a 3-month history of progressive neck pain and difficulty walking. On clinical examination, he showed upper dorsal bilateral gray blue hyperpigmentation, quadriparesis and bilateral hypoesthesia below C4. Cervical magnetic resonance imaging (MRI) T1-weighted images without contrast showed a C3-C4 intradural, extramedullary lesion. The patient underwent total microsurgical resection of the lesion. Histological and immunohistochemical analyses confirmed the diagnosis of melanocytoma. Another skin biopsy of the abnormal area showed histological findings of a blue skin nevus. Eight years after resection the patient presented with recurrent symptoms, which were similar to his initial presentation. Cervical MRI s...
BMC Medical Education
Background Different variables have been used to predict the academic performance of students in ... more Background Different variables have been used to predict the academic performance of students in medical schools. The aim of this study was to assess the effect of demographics, admission system, and high-school background on the academic performance of medical students. Methods We conducted this longitudinal cohort study on 808 students admitted to the Faculty of. Medicine at the University of Jordan (Amman, Jordan), in the years 2012 and 2013. Admission pathway, and academic performance data were collected and analyzed. Results A total of 808 students [i.e., 426 (52.7%) females, and 382(47.3%) males] were identified. Admitted students were holding 17 different types of high school degrees, and were accepted through 6 different quota pathways (open competition [National unified admission], underprivileged [“Makrumah”], parallel, children of university staff, international students, and others). Students admitted through the open competition and the underprivileged quota(Makrumah) w...
Scientific Reports
Given the massive use of facemasks (FMs) during the covid-19 pandemic, concerns have been raised ... more Given the massive use of facemasks (FMs) during the covid-19 pandemic, concerns have been raised regarding the effect of FMs wearing on overall health. This study aimed at evaluating the effect of surgical FM on brain neuro-electrical activity. Electroencephalography (EEG) background frequency (BGF) and background amplitude (BGA) was performed on 30 volunteers before (baseline), during and after wearing a FM for 60 min. Measurements were done during normal ventilation, hyperventilation and post-hyperventilation (PHVR). Blood gas levels were assessed at baseline and after FM use. EEG analysis concerning baseline (without FM) (BGA), was 47.69 ± 18.60 µV, wearing FM, BGA was 48.45 ± 17.79 µV, post FM use BGA was 48.08 ± 18.30 µV. There were no statistically significant differences between baseline BGA and BGA under FM and post FM. BGF, Baseline data were 10.27 ± 0.79, FM use 10.30 ± 0.76 and post FM use was 10.33 ± 0.76. There were no statistically significant differences between basel...
Materials Science Forum, 2016
One of the key factors that play an important role in the performance of a solid propellant rocke... more One of the key factors that play an important role in the performance of a solid propellant rocket is dependent on its burning rate. A strand burner is a type of apparatus used to measure the propellant burning rate at elevated pressure. This study investigates the relation between burning rates of aluminized ammonium perchlorate at low pressure. Chamber pressure was varied from 1 atm, 3 atm, 5 atm and 7 atm. This study shows that propellant burning rate is about 50%-62% higher when the burn rate test is conducted at atmospheric condition compared to when it is done in inert gas. The investigation’s results also revealed an increasing propellant burning rate when the chamber pressure is increased. In conclusion, the burning condition and chamber pressure influences the propellant burning rate.
Journal of Musculoskeletal & Neuronal Interactions, 2021
Objectives: To investigate the effect of vagus nerve stimulation (VNS) on the bone mineral densit... more Objectives: To investigate the effect of vagus nerve stimulation (VNS) on the bone mineral density (BMD) in epileptic patients. Methods: A prospective cohort study was conducted on individuals with refractory seizures who underwent VNS surgery between January 2012 and December 2018. BMD was measured preoperatively and between 6 months and one year after surgery. Results: Twenty-one patients (mean age (±SD)=23.6±12.3 years) were recruited for the implantation of a VNS device. The mean absolute increase in lumbar BMD in the 21 patients was 0.04±0.04 g/cm2 resulting in an overall percent increase from baseline of 4.7±6.1%. BMD increased by an amount ≥ the least significant change (LSC) for the lumbar spine in 13 patients (61.9%). The lumbar Z score also increased in these patients from -1.22±1.15 to -0.88±1.22, P=0.006). Pre and Post VNA femoral BMD was measured in only 11 patients and, of those 3 showed a significant increase in BMD, 1 a significant decrease and 7 no change. Conclusio...
Glioblastoma
Glioblastoma (GBM) is the most aggressive malignant primary brain tumor. With an incidence rate o... more Glioblastoma (GBM) is the most aggressive malignant primary brain tumor. With an incidence rate of 3.19 per 100,000 persons in the United States and a median age of 64 years, it is uncommon in children. The incidence is 1.6 times higher in males compared to females and 2.0 times higher in Caucasians compared to Africans and Afro-Americans, with lower incidence in Asians and American Indians. GBM is commonly located in the supratentorial region (frontal, temporal, parietal, and occipital lobes) and is rarely located in cerebellum. Genetic and environmental factors have been investigated in GBM. Risk factors include prior radiotherapy, decreased susceptibility to allergy, immune factors and immune genes, as well as some single nucleotide polymorphisms detected by genomic analysis. Use of anti-inflammatory medication has been found to be protective against GBM. Survival from GBM is poor; only few patients survive 2.5 years and less than 5% of patients survive 5 years following diagnosis. Survival rates for patients with GBM have shown no notable improvement in population statistics in the last three decades. Molecular epidemiology integrates molecular technology into epidemiological studies and outcomes. The future of the epidemiology of Epidemiology of Glioblastoma 144 GBM will depend on multicenter studies generating large clinical data sets of genomic data potentially leading to further understanding of the roles of genes and environment in the development of this devastating disease.
Middle East Journal of Anaesthesiology, Feb 1, 2009
Objective: Electrocorticography (ECoG) may be used to guide epilepsy surgery. However, anesthetic... more Objective: Electrocorticography (ECoG) may be used to guide epilepsy surgery. However, anesthetics can suppress epileptiform activity or induce confounding burst-suppression patterns and the relationship between ECoG results and seizure outcome is controversial. In this study, we evaluated the ECoG activity under several different anesthetics and examined the relationship between ECoG and outcome. Methods: We retrospectively studied 44 patients who had ECoG during epilepsy surgery. Anesthesia was with fentanyl and isoflurane (n = 19), fentanyl and sevoflurane (n = 9), remifentanil and sevoflurane (n = 5), remifentanil and propofol (n = 9), and fentanyl with propofol sedation during local anesthesia (n = 2). Pre-resection ECoG was considered satisfactory if epileptiform activity was present and there was no burst-suppression. Post-resection ECoG was graded according to residual epileptiform activity: A (none), B (mild), C (moderate). Seizure outcome was graded: I (seizure free without medication), II (seizure free with medication), III (> 50% seizure reduction) or IV (< 50% seizure reduction). Grades I-III were considered beneficial. Results: ECoG was satisfactory in 43 of the 44 surgeries, but one of the 11 recordings during propofol showed no epileptiform activity. Thirty-six of 37 patients (97%) with ECoG grade A or B and five of seven patients (71%) with ECoG grade C benefited from epilepsy surgery. Chi-squared, p > 0.05. Conclusions: Satisfactory ECoG is possible using isoflurane or sevoflurane with nitrous oxide and fentanyl or remifentanil or using propofol and remifentanil. However, one of eleven ECoGs under propofol was negative for epileptiform activity. The amount of post-resection ECoG epileptiform activity does not significantly correlate with seizure outcome.
Neurosciences, Oct 1, 2010
Secondary aneurysmal bone cyst in fibrous dysplasia is exceedingly rare, especially in the skull ... more Secondary aneurysmal bone cyst in fibrous dysplasia is exceedingly rare, especially in the skull and particularly in the frontal bone. We present a case of aneurysmal bone cyst concomitant with fibrous dysplasia in the frontal bone in a 15-year-old male patient presenting with headache and euphoria with an uncharacteristic imaging appearance and treated successfully by total resection.
Textbook of Epilepsy Surgery, 2008