Transsulcal approach supported by navigation-guided neurophysiological monitoring for resection of paracentral cavernomas

Objectives

The aim of the study is to evaluate tools that can improve surgical precision and minimize surgical trauma for removal of cavernomas in the paracentral area. Moreover, the surgical strategies for the treatment of symptomatic epilepsy in cavernoma patients are discussed.

Patients and methods

Between June 2000 and July 2007, 17 patients suffering from paracentral cavernoma underwent surgery via a transsulcal approach with the aid of neuronavigation, functional mapping and neurophysiological intraoperative monitoring. To optimize outcome for procedures in the paracentral area, the hemosiderin-stained tissue was removed entirely except for a small proportion on the side of precentral gyrus.

Results

All cavernomas and their adjacent sulci could be precisely located with the aid of ultrasonography-assisted neuronavigation. By combining preoperative fMRI and intraoperative neurophysiological monitoring, including SEP, MEP and cortical mapping, the motor cortex could be defined in all cases. Thus damage to the primary motor area could be avoided during resection of cavernomas. All the lesions located in the paracentral area were removed completely via transsulcal microsurgical approach without neurological deficits. No significant seizures were induced during surgery.

Conclusions

The successful excision of these lesions was effected by the following four key factors: (1) the precise location of the lesion supported by intraoperative neuronavigation; (2) the preservation of the eloquent area with the aid of functional mapping; (3) a minimally invasive transsulcal microsurgical approach; and (4) the entire removal of cavernoma and hemosiderin-stained tissue.     

Vestibular schwannoma microsurgery with special reference to facial nerve preservation

Objective

To retrospectively study the outcomes of vestibular schwannoma (VS) resection.

Methods

Between January 2003 and December 2006, 103 consecutive patients who had undergone VS resection were included in this study. Medical records, operation summaries, follow-up data, and neuroradiological findings were analyzed. The relationship between tumor size, location, and topography relative to the facial nerve bundles was studied for a mean duration of 16 months (range: 3–39 months).

Results

Complete tumor resection in combination with anatomic preservation of the facial nerve was achieved in 101 (98.1%) cases. The facial nerve was fully preserved in 100% of cases with small or medium tumors and in 37/39 patients with large tumors. Overall, 83.5% of patients had normal or near-normal facial nerve function 3–12 months post-surgically. The mortality rate was 0%.

Conclusions

Even in large VS, preservation of facial nerve function (H-B Grade I or II) should be prioritized over total resection. For tumors >3 cm, the goal of low morbidity and maintenance of normal facial nerve function can be attained with the retrosigmoid transmeatal approach, refined microsurgical technique, and intraoperative facial nerve monitoring.     

Low field intraoperative MRI-guided surgery of gliomas: A single center experience

Introduction

The aim of this article is to report on our experience in using a low field intraoperative MRI (iMRI) system in glioma surgery and to summarize the hitherto use and benefits of iMRI in glioma surgery.

Patients and methods

Between July 2004 and May 2009, a total of 103 patients harboring gliomas underwent tumor resection with the use of a mobile low field iMRI in our institution. Surgeries were performed as standard micro-neurosurgical procedures using regular instrumentarium. All patients underwent early postoperative high field MRI to determine the extent of resection. Adjuvant treatment was conducted according to histopathological grading and standard of care.

Results

All tumors could be reliably visualized on intraoperative imaging. Intraoperative imaging revealed residual tumor tissue in 51 patients (49.5%), leading to further tumor resection in 31 patients (30.1%). Extended resection did not translate into a higher rate of neurological deficits. When analyzing survival of patients with glioblastoma, patients undergoing complete tumor resection did significantly better than patients with residual tumor (50% survival rate at 57.8 weeks vs. 33.8 weeks, log rank test p = 0.003), while younger age did not influence survival (p = 0.12).

Conclusion

Low field iMRI is a helpful tool in modern neurosurgery and facilitates brain tumor resection to a maximum safe extent. Its use translates into a better prognosis for these patients with devastating tumors. Future studies covering the use of iMRI will need to be conducted in a prospective, randomized fashion to prove the true benefit of iMRI in glioma surgery.     

Purely subcortical tumors in eloquent areas: Awake surgery and cortical and subcortical electrical stimulation (CSES) ensure safe and effective surgery

Objective

To analyze the efficacy and safety of cortical and subcortical electrical stimulation CSES and awake surgery to approach purely subcortical tumors in highly functional locations, particularly in guiding the choice of the best transcortical path.

Patients and methods

Prospective analysis of the surgical, neurological, and radiological outcome of patients harboring supratentorial, subcortically located brain tumors or vascular malformations who are operated on through awake surgery and CSES. Functional magnetic resonance (fMRI; either sensory-motor or language, based on the location) was performed in order to confirm the proximity to functional cortical areas. Major white matter tracts were investigated by MRI diffusion tensor fiber tracking (DTI-ft). The Rankin modified score was chosen to express the pre and postoperative functional neurological status. Immediate postoperative MRI was used to evaluate the extent of resection.

Results

Seventeen patients were selected. The main distance of the tumors from the cortical surface was 18.2 mm (range 9–48 mm). Neuronavigation was used to show the most direct route to the tumor (transsulcal or transgyral), but CSES was fundamental to adapt the surgical corridor to the functional topography both cortically and subcortically. If the transgyral route was chosen, CSES helped to detect a non-eloquent area. When a transsulcal route was preferred, CSES documented the presence or absence of function in the deep sulcus. The transient postoperative morbidity was 76.4%, but at last follow-up (range 4–20 months), all the patients regained preoperative status and 2 improved. Postoperative MRI demonstrated complete resection in all cases.

Conclusions

Approaching purely subcortical tumors requires microsurgical skills, but in eloquent areas, functional topography monitoring is mandatory to allow safe surgery. CSES in an awake patient is a method that produces very good results in terms of resection and neurological outcome.     

Atypical causes of nontraumatic intracranial subarachnoid hemorrhage

Background

To analyze the management and outcome of patients presenting with atypical causes of intracranial subarachnoid hemorrhage (SAH).

Methods

We performed a review of our last 820 nontraumatic-SAH patients and analyzed the management and outcome of patients where the SAH origin was not a ruptured aneurysm. The Glasgow Outcome Scale (GOS) was used to assess outcome 3 months after event.

Results

Thirty-two patients had atypical causes of SAH. In 15 patients with Hunt and Hess (H&H) scores from 1 to 3 without focal neurological deficit (FND), 8 perimesencephalic nonaneurysmatic SAH, 4 blood coagulation disorders, 1 sinus thrombosis, 1 vasculitis, and 1 unknown-origin-SAH (UOS) were diagnosed. Fourteen (93%) of these 15 patients were conservatively treated. In 17 patients with H&H scores from 3 to 5 and FND, 8 tumors, 1 cavernoma, 1 sinus thrombosis, 1 arteriovenous malformation, 1 blood coagulation disorders, 2 UOS, and 3 dural fistulas were diagnosed. Fifteen (88%) of these 17 patients were interventionally treated. The neurological condition 3 months later was good (GOS 4 and 5) in 12 of the 15 cases (80%) admitted with low-H&H scores, as well as in 13 of the 17 cases (76%) admitted with high-H&H scores. Three patients died and four developed a severe disability.

Conclusions

Patients presenting with atypical causes of SAH and high-H&H scores at admission are likely to harbor an intracranial organic process producing the bleeding. Despite this poor initial condition, their 3-month outcome can be similar to those of patients with low-H&H scores if the origin of the bleeding is properly treated.     

Fibrinolytic therapy versus craniotomy for anticoagulant-associated intracerebral hemorrhage

Object

Anticoagulant-associated intracerebral hemorrhages (AAICH) have a high morbidity and mortality, necessitating urgent treatment. We examined outcomes after conventional craniotomy and stereotactic fibrinolytic therapy in a series of patients with anticoagulant-associated hemorrhages.

Methods

Among 129 consecutive surgically treated patients with supratentorial intracerebral hemorrhage, 27 patients with AAICH were identified (mean age 62; range 36–79). Thirteen patients underwent craniotomy for surgical hematoma evacuation, and 14 patients hematoma puncture and catheter placement for clot lysis. The groups had comparable major prognostic factors such as hematoma volume, age, and Glasgow coma scale (GCS) score at admission.

Results

Nine patients died despite treatment (mortality = 33%). Mortality in the craniotomy group was comparable to that of the lysis group (46% versus 21%; p = 0.13). Good outcomes (Glasgow outcome score of 4 or 5) were seen in 3 craniotomy patients (23%) and 2 fibrinolysis patients (14%). Half the patients survived with major neurological deficits (GOS 2 or 3) (n = 13; 48%). One rebleed was observed two days after uneventful craniotomy and hematoma removal, while no patient who underwent fibrinolysis had rebleeding.

Conclusions

Approximately one-fifth of patients with AAICH managed surgically may have good outcomes. Mortality and favourable outcome rates are comparable between craniotomy and fibrinolytic therapy. Fibrinolytic therapy appears to be a reasonable less invasive alternative treatment modality for intracerebral hemorrhage in the anticoagulated patient.     

The combination of neuronavigation with transcranial magnetic stimulation for treatment of opercular gliomas of the dominant brain hemisphere

Objective

The objective of this study is to investigate the application of transcranial magnetic stimulation combined with neuronavigation for preoperative mapping of the language area in neurosurgical interventions on the opercular area of the dominant hemisphere.

Methods

Five patients were operated upon gliomas in the opercular area. For localization of the speech area a transcranial magnetic stimulator MEDTRONIC-MagPro was used. BrainLAB-VectorVision Neuronavigation system was utilized for precise planning of the operative approach.

Results

Gross total resection was achieved in all patients. Three-month postoperative follow-up was done. Three of the patients had a transient postoperative motor aphasia which resolved within 1 month.

Conclusion

This method is useful for preoperative localization of the speech area, as well as preoperative planning of the operative approach and intra-operative planning of the direction of brain retraction and operative corridor.     

Management of hydrocephalus secondary to pineal region tumors

Background

Hydrocephalus is often secondary to pineal region tumors. Hydrocephalus can lead to high intracranial pressure, which in turn results in disturbance of consciousness, cerebral hernia, and even death. Hydrocephalus management is important in the treatment of pineal region tumors. It is still controversial regarding to when and how to treat hydrocephalus secondary to pineal region tumors. The objective of this study is to investigate the management of hydrocephalus secondary to pineal region tumors.

Methods

We retrospectively analyzed records for 51 patients admitted to the department of Neurosurgery, Jinling Hospital from April 1997 to September 2010 with hydrocephalus secondary to pineal region tumors treated through occipital transtentorial approach.

Results

Preoperative ventricular drainage was performed on one patient, and ventriculoperitoneal shunts were performed on two patients. Intraoperative ventriculocisternal shunts were performed on 35 patients (the remission rate was 88.6%), no treatments on 15 patients (the remission rate was 46.7%), and ventricular drainages on three patients. VP shunts were performed on 12 patients with no remission after the operation.

Conclusion

Pineal region tumors resection usually should be performed before shunting, unless there is an acute obstructive hydrocephalus. The posterior third ventricle should be opened after tumor resection. Intraoperative third ventriculostomy and ventriculocisternal shunt are reliable ways to manage hydrocephalus secondary to pineal region tumors.     

Intraoperative neurophysiologic monitoring and neurologic outcomes in patients with epidural spine tumors

Purpose

Multimodal intraoperative neurophysiologic monitoring (IOM) provides assessment of spinal cord pathways during neurosurgery. Despite widespread use, few data exist regarding sensitivity and specificity of IOM in predicting neurologic outcome during decompression and instrumentation for epidural spine tumors.

Methods

Retrospective analysis evaluated consecutive spine procedures involving IOM modalities (somatosensory evoked potentials [SSEP], motor evoked potentials [MEP], and electromyography [(EMG]) from 2007 to 2009. Demographic and surgical information, intraoperative neurophysiologic data, and pre- and postoperative neurologic status were collected. All cases involved neoplastic epidural spinal cord compression by a primary or metastatic tumor and included posterolateral decompression and instrumented fusion.

Results

Two-hundred and eight consecutive patients had spine surgery during this time period and one hundred and fifty-two met inclusion criteria. All patients had SSEP monitoring, with 4 having transient changes and 7 persistent changes. One hundred and twenty-two patients had combined SSEP and MEP monitoring, with 3 having transient changes and 4 persistent changes in MEP signals. Two patients had neurophysiologic changes associated with hypotension and correction led to normalization. One developed new neurologic deficits after surgery. Two from the total cohort had new postoperative neurologic deficits. One had a transient decrease in MEP amplitude while the other had no intraoperative changes.

Discussion

These cases are often long with significant blood loss, and stability of multiple IOM modalities provides reassurance that spinal cord function remains intact. Signal changes should result in scrutiny of blood pressure, surgical technique and anesthesia. Preserved IOM signals are suggestive of preserved neurologic outcome.     

Preoperative spinal tumor embolization: An institutional experience with Onyx

Background

Preoperative embolization has the potential to decrease intraoperative blood loss and facilitate spinal cord decompression and tumor resection.

Objective

We report our institutional experience with the embolization of hypervascular extradural spinal tumors with Onyx as well as earlier embolic agents in a series of 28 patients.

Methods

A retrospective case review was conducted on patients undergoing preoperative transarterial embolization of a spinal tumor between 1995 and 2012 at our institution.

Results

Twenty-eight patients met the inclusion criteria, with a mean age of 60.6 years. Twenty-eight patients had metastatic tumors. In 14 (50%) patients the metastases were from renal cell carcinomas. Fifty-four vessels were embolized using PVA, NBCA, Onyx, coils, or embospheres. Sixteen patients were treated with Onyx, 6 patients with PVA, 3 patients with embospheres, 2 patients with NBCA, and 3 patients with a combination of embolic agents. The average decrease in tumor blush was 97.8% with Onyx versus 92.7% with the rest of the embolic agents (p = 0.08). The estimated blood loss was 1616 ml (range 350–5000 ml). Blood loss was 750 cm³ on average with Onyx versus 1844 with the rest of the embolic agents (p = 0.14). The mean length of stay was 16 days. The mortality rate was zero. Pre- and post-operative modified Rankin Score (mRS) did not differ significantly in the series (3.12 versus 3.10, respectively, p = 0.9).

Conclusion

In our experience, the use of transarterial tumor embolization as an adjunct for spinal surgery is a safe and feasible option.     

Awake craniotomy and electrophysiological mapping for eloquent area tumours

Objective

An awake craniotomy facilitates radical excision of eloquent area gliomas and ensures neural integrity during the excision. The study describes our experience with 67 consecutive awake craniotomies for the excision of such tumours.

Methods

Sixty-seven patients with gliomas in or adjacent to eloquent areas were included in this study. The patient was awake during the procedure and intraoperative cortical and white matter stimulation was performed to safely maximize the extent of surgical resection.

Results

Of the 883 patients who underwent craniotomies for supratentorial intraaxial tumours during the study period, 84 were chosen for an awake craniotomy. Sixty-seven with a histological diagnosis of glioma were included in this study. There were 55 men and 12 women with a median age of 34.6 years. Forty-two (62.6%) patients had positive localization on cortical stimulation. In 6 (8.9%) patients white matter stimulation was positive, five of whom had responses at the end of a radical excision. In 3 patients who developed a neurological deficit during tumour removal, white matter stimulation was negative and cessation of the surgery did not result in neurological improvement. Sixteen patients (24.6%) had intraoperative neurological deficits at the time of wound closure, 9 (13.4%) of whom had persistent mild neurological deficits at discharge, while the remaining 7 improved to normal. At a mean follow-up of 40.8 months, only 4 (5.9%) of these 9 patients had persistent neurological deficits.

Conclusion

Awake craniotomy for excision of eloquent area gliomas enable accurate mapping of motor and language areas as well as continuous neurological monitoring during tumour removal. Furthermore, positive responses on white matter stimulation indicate close proximity of eloquent cortex and projection fibres. This should alert the surgeon to the possibility of postoperative deficits to change the surgical strategy. Thus the surgeon can resect tumour safely, with the knowledge that he has not damaged neurological function up to that point in time thus maximizing the tumour resection and minimizing neurological deficits.     

An analysis of related factors of surgical results for patients with craniopharyngiomas

Objective

The objective of this study was to retrospectively review the surgical results following gross total resection and partial resection with or without radiotherapy for craniopharyngiomas and analyze the related factors of surgical results.

Methods

From 1994 to 2009, 214 patients underwent 219 procedures for craniopharyngiomas. We retrospectively reviewed the pre- and postoperative data of patients, reported the perioperative and long-term surgical results and analyzed the influencing factors and the relationship between hypothalamic involvement and postoperative quality of life.

Results

Gross total resection was achieved in 154 procedures (70.3%). Perioperative mortality was 5%. Perioperative hyperpyrexia was the most significant risk factor for perioperative mortality. A total of 151 patients were followed from 6 months to 190 months. There were significant differences in recurrence rate and overall survival between gross total resection and limited resection (P < 0.05). There was significant difference in recurrence rate between limited resection and limited resection with radiotherapy (P < 0.01), but it did not reach statistical difference between gross total resection and gross total resection with radiotherapy. The factors strongly influencing overall survival include old patients, partial resection and recurrent tumors. The preoperative hypothalamic involvement negatively correlates with the postoperative quality of life in patients with craniopharyngiomas.

Conclusion

The preoperative CT/MR imaging provides clues of the relationship between tumor and surrounding structures. Gross total resection should be achieved in the treatment of craniopharyngiomas on the condition that hypothalamus is preserved. The patients who undergo limited resection should receive conventional radiotherapy or gamma knife surgery.     

Modified Lund concept versus cerebral perfusion pressure-targeted therapy: a randomised controlled study in patients with secondary brain ischaemia

Purpose

Secondary brain ischaemia (SBI) usually develops after aneurysmal subarachnoid haemorrhage (SAH) and severe traumatic brain injury (TBI). Current approaches to managing these conditions are based either on intracranial pressure-targeted therapy (ICP-targeted) with cerebral microdialysis (CM) monitoring according to the modified Lund concept or cerebral perfusion pressure-targeted therapy (CPP-targeted). We present a prospective, randomised controlled study comparing relative effectiveness of the two management strategies.

Methods

Sixty comatose operated patients with SBI following aneurysmal SAH and severe TBI were randomised into ICP-targeted therapy with CM monitoring and CPP-targeted therapy groups. Mortality rates in both groups were calculated and tissue biochemical signs of cerebral ischaemia were analysed using CM. Measured CM data were related to outcome (Glasgow Outcome Scale [GOS] score 1, 2 and 3 for poor outcome or GOS score 4 and 5 for good outcome).

Results

Patients treated with ICP-targeted therapy with CM monitoring had significantly lower mortality rate as compared with those treated with CPP-targeted therapy (P = 0.03). Patients monitored with CM who had poor outcome had lower mean values of glucose and higher mean values of glycerol and lactate/pyruvate ratio as compared with those who had good outcome (glucose: P = 0.003; glycerol: P = 0.02; lactate/pyruvate ratio: P = 0.01). There was no difference in the mortality outcome between aneurysmal SAH and severe TBI in the two groups (P = 0.28 for ICP-targeted therapy with CM monitoring, P = 0.36 for CPP-targeted therapy). Also, there were no differences in the CM values between patients with aneurysmal SAH and severe TBI who underwent ICP-targeted therapy (glucose: P = 0.23; glycerol: P = 0.41; lactate/pyruvate ratio: P = 0.40).

Conclusion

The modified Lund concept, directed at bedside real-time monitoring of brain biochemistry by CM showed better results compared to CPP-targeted therapy in the treatment of comatose patients sustaining SBI after aneurysmal SAH and severe TBI.     

Intramedullary cavernous malformations: Clinical features and surgical technique via hemilaminectomy

Objective

The purpose of this study was to define the clinical features and the surgical technique of unilateral hemilaminectomy for treating intramedullary cavernous malformations.

Materials and methods

Retrospective chart was performed in 16 patients with histologically diagnosed intramedullary cavernous malformations. All patients were treated with unilateral hemilaminectomy and microsurgical resection of the malformations. The pre- and postoperative neurological state was evaluated using Frankel scale.

Results

There were nine females and seven males (mean age 38 years) harbouring symptomatic intramedullary cavernous malformations. The annual retrospective haemorrhage rate was 3.1% per patient/year. All cavernous malformations were completely resected. Twelve of 16 patients experienced the improvement of the neurological state and in four patients, clinical features remained unchanged during the follow-up period. Static and dynamic plain radiograph film showed none of them had spinal deformity or spinal instability.

Conclusion

According to the defined bleeding risk, symptomatic and MRI-morphologically growing intramedullary cavernous malformations should be totally surgically removed, to avoid the recurrence and rebleeding of the residue. A least traumatic myelotomy, as well as a meticulous microsurgical technique and the intraoperative somatosensory evoked potentials monitoring, together with selection of a minimally invasive microsurgical approach (hemilaminectomy), leads to a favourable outcome and prevents additional morbidity.     

Effect of progesterone administration on prognosis of patients with diffuse axonal injury due to severe head trauma

Objective

Severe traumatic brain injury (TBI) has a major role in mortality rate among the other types of trauma. The aim of this clinical study was to assess the effect of progesterone on the improvement of neurologic outcome in patients with acute severe TBI.

Methods

A total of 76 patients who had arrived within 8 h of injury with a Glasgow Coma Score ≤8 were enrolled in the study. In a randomized style 38 received progesterone (1 mg/kg per 12 h for 5 days) and 38 did not.

Results

There was a better recovery rate and GOS score for the patients who were given progesterone than for those in the control group in a 3-months follow-up period (50% vs. 21%); subgroup analysis showed a significant difference in the percentage of favorable outcome between the two groups with GCS of 5–8 (p = 0.03).

Conclusion

The use of progesterone may significantly improve neurologic outcome of patients suffering severe TBI up to 3 months after injury, especially those with 5 ≤ GCS ≤ 8, providing a potential benefit to the treatment of acute severe TBI patients. Considering this drug had no significant side effects, so progesterone could be used in patients with severe TBI as a neuro-protective drug.     

Surgical treatment and outcome of skull base meningiomas with extracranial extensions

Objective

Recurrent cranial base meningiomas occasionally extend into craniofacial structures, and are one of the most difficult tumors to surgically manage. We reviewed our experience of surgical treatment in a series of patients with meningiomas showing extensive extracranial extensions.

Methods

We surgically treated a total of 10 patients with recurrent cranial base meningiomas with large extension to multiple craniofacial structures. All patients underwent orbitozygomatic or zygomatic frontotemporal craniotomy for surgical resection of the tumor. An endoscopic endonasal technique was also employed, if necessary, as an adjunct to the transcranial approach.

Results

Eight patients were treated solely with a frontotemporal approach associated with an extended resection of the floor of the middle fossa. In 2 patients, an endoscopic endonasal approach was additionally required for resection of tumors located in the nasal cavity and ethmoid sinus. A gross total resection was achieved without serious surgical complications in 9 out of the 10 patients. In all patients, the tumors were found to invade the surrounding tissue such as the bone and skeletal muscle to varying degrees.

Conclusion

Our data indicate that recurrent craniofacial meningiomas can usually be managed by using a lateral cranial base approach. Whereas it would be expected that a radical resection may prevent further recurrence with an acceptable quality of life, a long-term follow-up would be required for confirming the benefit of this treatment strategy.     

Long-term neurological and neuropsychological outcome in patients with severe traumatic brain injury

Background

Severe traumatic brain injury (TBI) remains a major cause of death and disability worldwide. The aim of the study was to evaluate predictors for neurological and neuropsychological long-term outcome in patients with severe TBI treated according to an intracranial pressure (ICP-) targeted therapy.

Methods

From 08/2005 to 12/2008, 46 patients with severe TBI and more than 12 h of intensive care treatment were included in this study. Neurological outcome was assessed with the Glasgow Outcome Scale (GOS). Neuropsychological performance assessing 9 different domains was evaluated at long-term follow-up (median 20.5 months; range 10–46). Logistic regression was used to identify favourable outcomes according to the GOS and Fisher's exact tests were used to identify predictors of severe neuropsychological impairments at follow-up.

Results

Twenty-nine patients were available for neuropsychological assessment at long-term follow-up. Only 2 out of 29 patients presented normal or average neuropsychological findings throughout all 9 neuropsychological domains at long-term follow-up. The percentage of a favourable outcome (GOS 4-5) increased from 13.8% at hospital discharge to 75.8% at rehabilitation discharge to 79.3% at long-term follow-up, respectively. Age ≤40 was found to be a strong predictor of favourable outcome at follow-up (OR 5.95, 95% CI 1.41 25.00, p = 0.015). The GOS at hospital discharge was not a predictor for severe impairments in any of the 9 different neuropsychological domains (all p-values were p > 0.268). In contrast, the GOS at rehabilitation discharge was found to be a predictor of severe impairments at follow-up in all but one domain assessed (all p-values less than p < 0.038).

Conclusions

The GOS at rehabilitation discharge should be regarded as a better predictor for neuropsychological impairments at long-term follow-up than the GOS at hospital discharge. Even in patients with favourable GOS after finishing a course of rehabilitation, three quarters of these patients may have at least one severe neuropsychological deficit. Therefore, it remains of paramount importance to provide long-term neuropsychological support to further improve outcome after TBI.     

Identification of venous variants in the pineal region with three-dimensional preoperative magnetic resonance imaging navigation in patients harbouring tumors in this area: significance for surgical approach to the lesion

Object

The purpose of this study was to identify the anatomy of pineal region venous complex using neuronavigation software when distorted by the presence of a space-occupying lesion and to describe the anatomical relationship between lesion and veins. Moreover we discuss its influence on the choice of the surgical strategy.

Methods

Of the 33 patients treated at our Institute for pineal region tumors between 2003 and 2008 we used the neuronavigation software to depict the venous system of the pineal region in 14 patients. We focused on depiction of the basal vein of Rosenthal (BV), the internal cerebral vein (ICV) and the vein of Galen: connection patterns between the veins and the type of anatomical distortion caused by the lesion were investigated and classified.

Results

Using the neuronavigation software for three-dimensional (3D) reconstruction of MRI images the ICV was clearly depicted in all patients on both sides (100%). Last segment of the BV was identified in 25 sides on a total of 28 (89.3%) and absent in 3 of the 28 sides (10.7%). Studying the distortion effect of the tumor on the galenic venous system, three directions of displacement were observed: craniocaudal, anteroposterior and lateral. Seven patients presented a cranial dislocation, 5 patients caudal dislocation and there was no craniocaudal shift in 2 patients. Considering the anteroposterior displacement: 3 subjects showed an anterior shift of the veins, 5 subjects posterior shift and no anterioposterior shift was present in 6 patients. Only 2 of the 14 patients presented lateral displacement of the veins. The principal approaches used in this series were: supracerebellar infratentorial and interhemispheric parieto-occipital. The craniocaudal displacement of the pineal veins seems to be the most important for the choice of the approach.

Conclusion

The galenic venous system has a central role in the surgery pineal region tumors. Our study demonstrates that the architecture of the pineal veins and their anatomical relationship with the lesion can be depicted with great accuracy by using 3D neuronavigation software in order to facilitate surgical planning and intraoperative orientation.     

Mobile Computed Tomography : Early Experience in Korea

Objective

With improved technology, the values of intraoperative computed tomography (iCT) have been reevaluated. We describe our early clinical experience with a mobile CT (mCT) system for iCT and discuss its clinical applications, advantages and limitations.

Methods

Compared with intraoperative magnetic resonance imaging, this mCT system has no need for major reconstruction of a preexisting operating room for shielding, or for specialized instruments or equipment. Patients are placed on a radiolucent head clamp that fits within the gantry. Because it consists simply of a scanner and a workstation, it can be moved between locations such as an operating room, an intensive care unit (ICU) or an emergency room without difficulty. Furthermore, it can achieve nearly all types of CT scanning procedures such as enhancement, temporal bone imaging, angiography and three-dimensional reconstruction.

Results

For intracranial surgery, mCT can be used for intraoperative real-time neuronavigation by interacting with preoperative images. It can also be used for intraoperative confirmation of the extent of resection of intracranial lesions and for immediate checks for preventing intraoperative unexpected accidents. Therefore, the goals of maximal resection or optimal treatment can be achieved without any guesswork. Furthermore, mCT can achieve improved patient care with safety and faster diagnosis for patients in an ICU who might be subjected to a ventilator and/or various monitoring devices.

Conclusion

Our initial experience demonstrates that mCT with high-quality imaging offers very useful information in various clinical situations.     

Dynamic imaging of seizure activity in pediatric epilepsy patients

Objective

To investigate the feasibility of using noninvasive EEG source imaging approach to image continuous seizure activity in pediatric epilepsy patients.

Methods

Nine pediatric patients with medically intractable epilepsy were included in this study. Eight of the patients had extratemporal lobe epilepsy and one had temporal lobe epilepsy. All of the patients underwent resective surgery and seven of them underwent intracranial EEG (iEEG) monitoring. The ictal EEG was analyzed using a noninvasive dynamic seizure imaging (DSI) approach. The DSI approach separates scalp EEGs into independent components and extracts the spatio-temporal ictal features to achieve dynamic imaging of seizure sources. Surgical resection and intracranial recordings were used to validate the noninvasive imaging results.

Results

The DSI determined seizure onset zones (SOZs) in these patients were localized within or in close vicinity to the surgically resected region. In the seven patients with intracranial monitoring, the estimated seizure onset sources were concordant with the seizure onset zones of iEEG. The DSI also localized the multiple foci involved in the later seizure propagation, which were confirmed by the iEEG recordings.

Conclusions

Dynamic seizure imaging can noninvasively image the seizure activations in pediatric patients with both temporal and extratemporal lobe epilepsy.

Significance

EEG seizure imaging can potentially be used to noninvasively image the SOZs and aid the pre-surgical planning in pediatric epilepsy patients.