orhan barlas | Istanbul University (original) (raw)
Papers by orhan barlas
✔ Objective: To present the results, technique and indications of decompressive hemicraniectomy i... more ✔ Objective: To present the results, technique and indications of decompressive hemicraniectomy in patients with unilateral transtentorial herniation. Methods: Ten consecutive patients with intracranial hypertension refractory to medical management and transtentorial herniation were treated with decompressive hemicraniectomy over a 3-year period with the following diagnoses: malignant infarction (3 patients), subarachnoid hemorrhage and vasospasm (2 patients), traumatic brain injury (3 patients), spontanous intracerebral hemorrhage, and venous thrombosis. Neurological status was assessed by the Glasgow Coma Scale (GCS) and by the modified Rankin Scale (mRS) on admission, and by the mRS on discharge, and on follow-up examinations. Computerized tomography (CT) scans performed preoperatively and on the first, 7th postoperative days, and at one month were assessed for trastentorial herniation and midline shift. A decompressive hemicraniectomy, at least 14 by 11 cm was performed in all p...
Superior sagittal sinus thrombosis (SSST) is a rare entity, most often arising from infections, d... more Superior sagittal sinus thrombosis (SSST) is a rare entity, most often arising from infections, dehydration, and hematologic disorders. Development of this condition secondary to trauma is extremely rare. In this report, a 13-year-old boy who developed SSST following a closed head injury is presented. Imaging studies showed SSST caused by a depressed skull fracture. Neurologic examination of the patient was normal other than bilateral papillary stasis. He was treated with antiedematous and anticonvulsant drugs. Magnetic resonance venography obtained eight months after the diagnosis showed unoccluded superior sagittal sinus, neurologic examination findings were normal, as well.
World Neurosurgery
BACKGROUND Microelectrode recording (MER)-guided deep brain stimulation (DBS) remains the standar... more BACKGROUND Microelectrode recording (MER)-guided deep brain stimulation (DBS) remains the standard electrophysiological procedure to place the DBS lead at the optimal target. When single-track MER or test stimulation yields suboptimal results, trajectory adjustments are needed. Intraoperative computed tomography (iCT) can be useful to visualize the microelectrode and verify possible adjustments. The aim of this study was to evaluate the effect of iCT in MER during frameless stereotactic DBS for Parkinson's disease (PD). METHODS We retrospectively collected 28 PD patients, of whom 19 received iCT and nine did not, and measured intracranial volume, cerebral volume, cerebrospinal fluid (CSF) volume, and pneumocephalus volume. Euclidean distance was assessed according to merged preoperative brain CT and magnetic resonance imaging and postoperative brain CT. RESULTS Fifty-six hemispheres in the 28 patients were analyzed for MER tracks. The patients who received iCT had a significantly lower mean number of MER tracks (1.6 vs. 2.6, p = 0.013) and lower mean Euclidean distance (2.2 mm vs. 2.7 mm, p = 0.033) compared to those who did not receive iCT. Although there was a trend of a decrease in pneumocephalus using intraoperative imaging, there was no significant difference in surgical time. CONCLUSIONS ICT can reduce the number of MER tracks and increase surgical accuracy. Further studies are warranted to investigate whether iCT can reduce surgical complications and improve surgical outcomes.
Bagcilar Medical Bulletin
Agri Agri Dernegi Nin Yayin Organidir the Journal of the Turkish Society of Algology, Aug 1, 2005
Trigeminal neuralgia is a painful condition of the face characterized by paroxysmal lancinating, ... more Trigeminal neuralgia is a painful condition of the face characterized by paroxysmal lancinating, shock-like pain confined to the somatosensory distribution of the trigeminal nerve. The etiology of most cases of trigeminal neuralgia has been suggested to be vascular compression of the central axons of the trigeminal nerve at the level of pontocerebellar region, so called hyperactive dysfunctional syndrome. Trigeminal neuralgia is the one of the most known pain syndromes. Several neurosurgical procedures have been developed for the treatment of idiopathic trigeminal neuralgia and in this review, idiopathic trigeminal neuralgia was discussed in aspect of different surgical modalities.
Turkish Neurosurgery, 2016
Turkiye Klinikleri Cerrahi Tıp Bilimleri Dergisi, 2006
Turkish Neurosurgery, 2015
British journal of neurosurgery, Jan 25, 2015
Percutaneous balloon compression (PBC) has been widely used in the treatment of trigeminal neural... more Percutaneous balloon compression (PBC) has been widely used in the treatment of trigeminal neuralgia. However, this technique has a steep learning curve and significant complications were reported that were related to foramen ovale puncturing. The aim of this study was to evaluate the clinical results of a small patient group who underwent neuronavigation-assisted PBC. An intraoperative computed tomography (CT) device (CereTom, Neurologica, Danvers, MA/USA) was used to obtain CT scans with 2-mm slice thicknesses. The data were transferred to a neuronavigation system planning station (BrainLab, Feldkirchen, Germany). A soft touch registration system was used for image registration. With the image guidance, a trajectory was defined and the foramen ovale was cannulated using neuronavigation and Hartel's landmarks. Sixteen procedures were performed on 13 patients (4 female and 9 male) without complications. The total length of the procedure was not more than 57 min in all instances....
Aǧrı : Ağrı (Algoloji) Derneği'nin Yayın organıdır = The journal of the Turkish Society of Algology, 2005
Trigeminal neuralgia is a painful condition of the face characterized by paroxysmal lancinating, ... more Trigeminal neuralgia is a painful condition of the face characterized by paroxysmal lancinating, shock-like pain confined to the somatosensory distribution of the trigeminal nerve. The etiology of most cases of trigeminal neuralgia has been suggested to be vascular compression of the central axons of the trigeminal nerve at the level of pontocerebellar region, so called hyperactive dysfunctional syndrome. Trigeminal neuralgia is the one of the most known pain syndromes. Several neurosurgical procedures have been developed for the treatment of idiopathic trigeminal neuralgia and in this review, idiopathic trigeminal neuralgia was discussed in aspect of different surgical modalities.
Surgical Neurology, 1982
A 50-year-old woman was first examined in the emergency room because of inadequate ventilation, r... more A 50-year-old woman was first examined in the emergency room because of inadequate ventilation, rapidly developing respiratory paralysis, and papilledema. Multiple cranial nerve palsies and tetraparesis were present. Carotid angiogram demonstrated bilateral ventricular dilatation. Facilities for computerized tomography and vertebral angiography were not available. Ventriculograms revealed a filling defect of the fourth ventricle without displacement of the midline structures. Immediate exploration of the posterior fossa through a suboccipital craniectomy permitted microsurgical excision of a meningioma of the lower clivus. Spontaneous respirations returned postoperatively and a complete return of neurological functions ensued. The pertinent literature is reviewed.
Neurosurgery, 1983
1. Neurosurgery. 1983 Jul;13(1):105-6. Sewing needle injuries of the brain. Barlas O,Gökay H. PMI... more 1. Neurosurgery. 1983 Jul;13(1):105-6. Sewing needle injuries of the brain. Barlas O,Gökay H. PMID: 6877560 [PubMed - indexed for MEDLINE]. Publication Types: Case Reports; Letter. MeSH Terms: Adult; Brain Injuries/epidemiology ...
Surgical Neurology, 1999
Bacterial brain abscesses can be diagnosed and treated with stereotactic aspiration. From 1991 to... more Bacterial brain abscesses can be diagnosed and treated with stereotactic aspiration. From 1991 to 1997 we have used computed tomography-guided stereotactic aspiration to diagnose and treat 21 patients with a total of 58 bacterial brain abscesses. The ages of the patients ranged from 4 to 72 years (median 25 years); 11 of these 21 patients had multiple abscesses. The number of abscesses per patient with multiple abscesses ranged from 2 to 9, all located deep in subcortical white matter. All patients underwent stereotactic surgical drainage and an 8-week intravenous antibiotic medical treatment. Of the 58 abscesses, 23 were aspirated. Of these 23 abscesses, 19 were radiologically stage III or IV and four were stage I or II. Pathological examination confirmed radiological staging in 19 patients (83%). Except for the three patients who have mild residual hemiparesis and one patient recovering from ataxia, all patients had complete neurological recovery. Computed tomography-guided stereotaxy achieved all the objectives of management; namely, ascertaining the diagnosis, draining the content of the mass, and obtaining pus for accurate bacteriological diagnosis without morbidity. Stereotactic aspiration combined with an 8-week intravenous antibiotic regimen has yielded an effective therapeutic result in all of our abscesses, small or large, solitary or multiple, superficial or deep-seated. A high radiological-pathological correlation was also deduced from this study.
Pediatric Neurosurgery, 1996
Gliomatosis cerebri is an infrequent tumor of neuroepithelial origin presenting with deterioratio... more Gliomatosis cerebri is an infrequent tumor of neuroepithelial origin presenting with deterioration of cognitive functions, behavioral and mental changes, motor weakness, headache, and seizures. Laboratory data are unconclusive. MRI appears to be the imaging modality of choice and mainly reveals a bilateral and diffuse infiltration of midline adjacent brain structures whose anatomical configuration remain intact. MRI- or CT-guided stereotactic biopsy is advised as the diagnostic procedure in suspected cases. A 9-year-old girl with diffuse cerebrospinal gliomatosis, investigated with sequential cranial CT scans, and MRI-verified spinal cord involvement is reported, and the corresponding literature is reviewed.
Pediatric Neurosurgery, 2001
A series of 30 documented cases of intracranial hydatid cyst out of 33 pediatric and 45 total pat... more A series of 30 documented cases of intracranial hydatid cyst out of 33 pediatric and 45 total patients admitted to the Department of Neurosurgery of the School of Medicine at Istanbul University within the years 1952-1996 is presented. The pediatric population consisted of 73% of the series. Twenty patients (66%) are alive and well after a follow-up period of 8-45 years (mean 21.5 years). Six patients (20%) died and 4 (13%) were lost to follow-up. There were 3 early postoperative deaths (10%), 2 being in the pre-CT era. In 4 cases (13%), brain involvement was secondary, and 2 cases (7%) had multiple intracranial hydatid cysts. Age ranged from 4 to 16 years, with a mean of 10.4. There were 5 intraventricular (17%) and 2 (7%) intracranial extradural settlements. No children with posterior fossa hydatid cyst, primary skull hydatidosis or concomitant spinal involvement were detected. One patient (3%) presented with "rhinorrhea" which in fact was a hydatid fluid leak. Preoperative pseudocerebellar syndrome, convulsion and extrapyramidal signs were seen in 6 patients each (20%). Five patients (17%) had permanent visual deficits, 3 being in pre-CT era. Out of 29 patients operated on, hydatid birth with intact cyst removal was achieved in 18 cases (62%), with no other manipulation needed. This rate has increased to 70% in the CT era. Intraoperative accidental rupture occurred in 8 cases (28%), of which 7 were localized frontally or had a frontal involvement (88% of the ruptured cases). Of the patients with intraoperative rupture, 5 are dead (63%) and they were all primary. In contrast, all 3 cases alive with intraoperative rupture are secondary. Three cases were punctured on purpose (10%). Four of the operated patients (14%) required long-term antiepileptic therapy, 3 having no preoperative seizures. Only 1 patient required a shunt (3%). Four cases had recurrence, all with intraoperative cyst rupture (14%). The long-term evaluation of the results yielded an overall mortality rate of 21%. Routine use of CT after the 80s decreased the rate to 14%. With the analysis of 50 years of data, it is strongly concluded that brain involvement in pediatric hydatid disease is a primary process if delayed diagnosis and insufficient treatment of extraneural hydatidosis are prevented.
Pediatric Neurosurgery, 1997
Three unusual cases of hydatid disease with central nervous system involvement are reported in th... more Three unusual cases of hydatid disease with central nervous system involvement are reported in the pediatric age group: a 9-year-old boy with a total number of 12 intracranial secondary hydatid cysts; a 13-year-old girl admitted in areflexia who survived after cyst puncture and successive mass removal, and a 14-year-old boy with a huge intracranial hydatid cyst weighing 770 g which was extracted without rupture. The article discusses the surgical problems, and the related literature is reviewed.
Parkinsonism & Related Disorders, 2007
✔ Objective: To present the results, technique and indications of decompressive hemicraniectomy i... more ✔ Objective: To present the results, technique and indications of decompressive hemicraniectomy in patients with unilateral transtentorial herniation. Methods: Ten consecutive patients with intracranial hypertension refractory to medical management and transtentorial herniation were treated with decompressive hemicraniectomy over a 3-year period with the following diagnoses: malignant infarction (3 patients), subarachnoid hemorrhage and vasospasm (2 patients), traumatic brain injury (3 patients), spontanous intracerebral hemorrhage, and venous thrombosis. Neurological status was assessed by the Glasgow Coma Scale (GCS) and by the modified Rankin Scale (mRS) on admission, and by the mRS on discharge, and on follow-up examinations. Computerized tomography (CT) scans performed preoperatively and on the first, 7th postoperative days, and at one month were assessed for trastentorial herniation and midline shift. A decompressive hemicraniectomy, at least 14 by 11 cm was performed in all p...
Superior sagittal sinus thrombosis (SSST) is a rare entity, most often arising from infections, d... more Superior sagittal sinus thrombosis (SSST) is a rare entity, most often arising from infections, dehydration, and hematologic disorders. Development of this condition secondary to trauma is extremely rare. In this report, a 13-year-old boy who developed SSST following a closed head injury is presented. Imaging studies showed SSST caused by a depressed skull fracture. Neurologic examination of the patient was normal other than bilateral papillary stasis. He was treated with antiedematous and anticonvulsant drugs. Magnetic resonance venography obtained eight months after the diagnosis showed unoccluded superior sagittal sinus, neurologic examination findings were normal, as well.
World Neurosurgery
BACKGROUND Microelectrode recording (MER)-guided deep brain stimulation (DBS) remains the standar... more BACKGROUND Microelectrode recording (MER)-guided deep brain stimulation (DBS) remains the standard electrophysiological procedure to place the DBS lead at the optimal target. When single-track MER or test stimulation yields suboptimal results, trajectory adjustments are needed. Intraoperative computed tomography (iCT) can be useful to visualize the microelectrode and verify possible adjustments. The aim of this study was to evaluate the effect of iCT in MER during frameless stereotactic DBS for Parkinson's disease (PD). METHODS We retrospectively collected 28 PD patients, of whom 19 received iCT and nine did not, and measured intracranial volume, cerebral volume, cerebrospinal fluid (CSF) volume, and pneumocephalus volume. Euclidean distance was assessed according to merged preoperative brain CT and magnetic resonance imaging and postoperative brain CT. RESULTS Fifty-six hemispheres in the 28 patients were analyzed for MER tracks. The patients who received iCT had a significantly lower mean number of MER tracks (1.6 vs. 2.6, p = 0.013) and lower mean Euclidean distance (2.2 mm vs. 2.7 mm, p = 0.033) compared to those who did not receive iCT. Although there was a trend of a decrease in pneumocephalus using intraoperative imaging, there was no significant difference in surgical time. CONCLUSIONS ICT can reduce the number of MER tracks and increase surgical accuracy. Further studies are warranted to investigate whether iCT can reduce surgical complications and improve surgical outcomes.
Bagcilar Medical Bulletin
Agri Agri Dernegi Nin Yayin Organidir the Journal of the Turkish Society of Algology, Aug 1, 2005
Trigeminal neuralgia is a painful condition of the face characterized by paroxysmal lancinating, ... more Trigeminal neuralgia is a painful condition of the face characterized by paroxysmal lancinating, shock-like pain confined to the somatosensory distribution of the trigeminal nerve. The etiology of most cases of trigeminal neuralgia has been suggested to be vascular compression of the central axons of the trigeminal nerve at the level of pontocerebellar region, so called hyperactive dysfunctional syndrome. Trigeminal neuralgia is the one of the most known pain syndromes. Several neurosurgical procedures have been developed for the treatment of idiopathic trigeminal neuralgia and in this review, idiopathic trigeminal neuralgia was discussed in aspect of different surgical modalities.
Turkish Neurosurgery, 2016
Turkiye Klinikleri Cerrahi Tıp Bilimleri Dergisi, 2006
Turkish Neurosurgery, 2015
British journal of neurosurgery, Jan 25, 2015
Percutaneous balloon compression (PBC) has been widely used in the treatment of trigeminal neural... more Percutaneous balloon compression (PBC) has been widely used in the treatment of trigeminal neuralgia. However, this technique has a steep learning curve and significant complications were reported that were related to foramen ovale puncturing. The aim of this study was to evaluate the clinical results of a small patient group who underwent neuronavigation-assisted PBC. An intraoperative computed tomography (CT) device (CereTom, Neurologica, Danvers, MA/USA) was used to obtain CT scans with 2-mm slice thicknesses. The data were transferred to a neuronavigation system planning station (BrainLab, Feldkirchen, Germany). A soft touch registration system was used for image registration. With the image guidance, a trajectory was defined and the foramen ovale was cannulated using neuronavigation and Hartel's landmarks. Sixteen procedures were performed on 13 patients (4 female and 9 male) without complications. The total length of the procedure was not more than 57 min in all instances....
Aǧrı : Ağrı (Algoloji) Derneği'nin Yayın organıdır = The journal of the Turkish Society of Algology, 2005
Trigeminal neuralgia is a painful condition of the face characterized by paroxysmal lancinating, ... more Trigeminal neuralgia is a painful condition of the face characterized by paroxysmal lancinating, shock-like pain confined to the somatosensory distribution of the trigeminal nerve. The etiology of most cases of trigeminal neuralgia has been suggested to be vascular compression of the central axons of the trigeminal nerve at the level of pontocerebellar region, so called hyperactive dysfunctional syndrome. Trigeminal neuralgia is the one of the most known pain syndromes. Several neurosurgical procedures have been developed for the treatment of idiopathic trigeminal neuralgia and in this review, idiopathic trigeminal neuralgia was discussed in aspect of different surgical modalities.
Surgical Neurology, 1982
A 50-year-old woman was first examined in the emergency room because of inadequate ventilation, r... more A 50-year-old woman was first examined in the emergency room because of inadequate ventilation, rapidly developing respiratory paralysis, and papilledema. Multiple cranial nerve palsies and tetraparesis were present. Carotid angiogram demonstrated bilateral ventricular dilatation. Facilities for computerized tomography and vertebral angiography were not available. Ventriculograms revealed a filling defect of the fourth ventricle without displacement of the midline structures. Immediate exploration of the posterior fossa through a suboccipital craniectomy permitted microsurgical excision of a meningioma of the lower clivus. Spontaneous respirations returned postoperatively and a complete return of neurological functions ensued. The pertinent literature is reviewed.
Neurosurgery, 1983
1. Neurosurgery. 1983 Jul;13(1):105-6. Sewing needle injuries of the brain. Barlas O,Gökay H. PMI... more 1. Neurosurgery. 1983 Jul;13(1):105-6. Sewing needle injuries of the brain. Barlas O,Gökay H. PMID: 6877560 [PubMed - indexed for MEDLINE]. Publication Types: Case Reports; Letter. MeSH Terms: Adult; Brain Injuries/epidemiology ...
Surgical Neurology, 1999
Bacterial brain abscesses can be diagnosed and treated with stereotactic aspiration. From 1991 to... more Bacterial brain abscesses can be diagnosed and treated with stereotactic aspiration. From 1991 to 1997 we have used computed tomography-guided stereotactic aspiration to diagnose and treat 21 patients with a total of 58 bacterial brain abscesses. The ages of the patients ranged from 4 to 72 years (median 25 years); 11 of these 21 patients had multiple abscesses. The number of abscesses per patient with multiple abscesses ranged from 2 to 9, all located deep in subcortical white matter. All patients underwent stereotactic surgical drainage and an 8-week intravenous antibiotic medical treatment. Of the 58 abscesses, 23 were aspirated. Of these 23 abscesses, 19 were radiologically stage III or IV and four were stage I or II. Pathological examination confirmed radiological staging in 19 patients (83%). Except for the three patients who have mild residual hemiparesis and one patient recovering from ataxia, all patients had complete neurological recovery. Computed tomography-guided stereotaxy achieved all the objectives of management; namely, ascertaining the diagnosis, draining the content of the mass, and obtaining pus for accurate bacteriological diagnosis without morbidity. Stereotactic aspiration combined with an 8-week intravenous antibiotic regimen has yielded an effective therapeutic result in all of our abscesses, small or large, solitary or multiple, superficial or deep-seated. A high radiological-pathological correlation was also deduced from this study.
Pediatric Neurosurgery, 1996
Gliomatosis cerebri is an infrequent tumor of neuroepithelial origin presenting with deterioratio... more Gliomatosis cerebri is an infrequent tumor of neuroepithelial origin presenting with deterioration of cognitive functions, behavioral and mental changes, motor weakness, headache, and seizures. Laboratory data are unconclusive. MRI appears to be the imaging modality of choice and mainly reveals a bilateral and diffuse infiltration of midline adjacent brain structures whose anatomical configuration remain intact. MRI- or CT-guided stereotactic biopsy is advised as the diagnostic procedure in suspected cases. A 9-year-old girl with diffuse cerebrospinal gliomatosis, investigated with sequential cranial CT scans, and MRI-verified spinal cord involvement is reported, and the corresponding literature is reviewed.
Pediatric Neurosurgery, 2001
A series of 30 documented cases of intracranial hydatid cyst out of 33 pediatric and 45 total pat... more A series of 30 documented cases of intracranial hydatid cyst out of 33 pediatric and 45 total patients admitted to the Department of Neurosurgery of the School of Medicine at Istanbul University within the years 1952-1996 is presented. The pediatric population consisted of 73% of the series. Twenty patients (66%) are alive and well after a follow-up period of 8-45 years (mean 21.5 years). Six patients (20%) died and 4 (13%) were lost to follow-up. There were 3 early postoperative deaths (10%), 2 being in the pre-CT era. In 4 cases (13%), brain involvement was secondary, and 2 cases (7%) had multiple intracranial hydatid cysts. Age ranged from 4 to 16 years, with a mean of 10.4. There were 5 intraventricular (17%) and 2 (7%) intracranial extradural settlements. No children with posterior fossa hydatid cyst, primary skull hydatidosis or concomitant spinal involvement were detected. One patient (3%) presented with "rhinorrhea" which in fact was a hydatid fluid leak. Preoperative pseudocerebellar syndrome, convulsion and extrapyramidal signs were seen in 6 patients each (20%). Five patients (17%) had permanent visual deficits, 3 being in pre-CT era. Out of 29 patients operated on, hydatid birth with intact cyst removal was achieved in 18 cases (62%), with no other manipulation needed. This rate has increased to 70% in the CT era. Intraoperative accidental rupture occurred in 8 cases (28%), of which 7 were localized frontally or had a frontal involvement (88% of the ruptured cases). Of the patients with intraoperative rupture, 5 are dead (63%) and they were all primary. In contrast, all 3 cases alive with intraoperative rupture are secondary. Three cases were punctured on purpose (10%). Four of the operated patients (14%) required long-term antiepileptic therapy, 3 having no preoperative seizures. Only 1 patient required a shunt (3%). Four cases had recurrence, all with intraoperative cyst rupture (14%). The long-term evaluation of the results yielded an overall mortality rate of 21%. Routine use of CT after the 80s decreased the rate to 14%. With the analysis of 50 years of data, it is strongly concluded that brain involvement in pediatric hydatid disease is a primary process if delayed diagnosis and insufficient treatment of extraneural hydatidosis are prevented.
Pediatric Neurosurgery, 1997
Three unusual cases of hydatid disease with central nervous system involvement are reported in th... more Three unusual cases of hydatid disease with central nervous system involvement are reported in the pediatric age group: a 9-year-old boy with a total number of 12 intracranial secondary hydatid cysts; a 13-year-old girl admitted in areflexia who survived after cyst puncture and successive mass removal, and a 14-year-old boy with a huge intracranial hydatid cyst weighing 770 g which was extracted without rupture. The article discusses the surgical problems, and the related literature is reviewed.
Parkinsonism & Related Disorders, 2007