Transient Neurological Deterioration Research Articles

Dorsal root entry zone fenestration for intramedullary ependymal cyst: illustrative case.

Intramedullary ependymal cysts are rare and difficult to distinguish from syringomyelia and neuroenteric cysts. Almost all cases in the literature have been case reports and have been performed with the traditional posterior median sulcus incision, which is difficult to identify accurately during spinal rotation. Approximately 40% of cases have transient neurological deterioration. The dorsal root entry zone has been proven to be an effective incision area in the treatment of intramedullary lesions, but so far, its utilization in intramedullary ependymal cysts has been rarely reported. This study is the first to report on six cases of intramedullary ependymal cysts treated with an 8-mm incision in the dorsal root entry zone to fully establish the communication between the cyst and the subarachnoid space. Imaging changes and neurological improvement were analyzed in all cases before and after surgery and were followed up for 49.7 months. The utilization of dorsal root entry zone fenestration in intramedullary ependymal cyst has demonstrated feasibility and effectiveness, ensuring the functional integrity of the posterior column.

Factors Affecting the Surgical Outcomes of Patients Treated With "de-tension" Surgical Strategy for Multilevel Ossification of the Posterior Longitudinal Ligament in the Thoracic Spine: A Minimum 2-year Follow-Up Study of 83 Patients in a Single Center.

Retrospective cohort study. To describe the clinical characteristics and surgical outcomes of patients with multilevel-ossification of the posterior longitudinal ligament (mT-OPLL), and to identify risk factors for unfavorable outcomes. Patients who were diagnosed with mT-OPLL and underwent one-stage thoracic posterior laminectomy combined with selective OPLL resection, spinal cord de-tension, and fusion surgery between August 2012 and October 2020 were recruited. Patients' demographic-, surgical- and radiological-related parameters were collected and analyzed. Neurological status was evaluated with mJOA score, and recovery rate (RR) was calculated using the Hirabayashi formula. According to RR, patients were divided into a favorable outcome group (FOG, RR ≥50%) and an unfavorable outcome group (UOG, RR <50%). Univariate and multivariate analyses were used to compare the difference between the 2 groups and to identify risk factors for unfavorable outcomes. A total of 83 patients were included, with an average age of 50.6 ± 8.3 years. Cerebrospinal fluid leakage (60.2%) and transient neurological deterioration (9.6%) were the most common complications. The average mJOA score improved from preoperative 4.3 ± 2.2 to 9.0 ± 2.4 at the last follow-up, and the mean RR was 74.9 ± 26.3%. Disease duration, preoperative nonambulatory status, and the number of decompressed levels were identified as potential risk factors by Univariate analysis (all P < .05). Multivariate analysis showed that the preoperative disease duration and nonambulatory status were independent risk factors for unfavorable outcomes. Long disease duration and nonambulatory status before surgery were independent risk factors for unfavorable outcomes.

Awake craniotomy for low-grade gliomas

Aim: The aim of this study was to evaluate the efficacy of awake brain surgery for benign glial brain tumours in the Department of Neurosurgery of the Military Institute of Medicine in Warsaw. Materials and methods: Between 2020 and 2021, 9 out of 17 patients with a radiological diagnosis of a low-grade glioma located within or in the vicinity of eloquent brain areas were operated on under awake conditions. The average preoperative tumour volume was 29.6 cm3. Preoperative management included a repeat magnetic resonance imaging supplemented with functional magnetic resonance imaging and tractography, as well as neuropsychological assessment. The cortex and subcortical structures were stimulated intraoperatively at 1.5–4 mA. The intraoperative assessment covered: motor functions, speech, and, additionally in two patients, visual field width and contralateral neglect. Results: Based on magnetic resonance imaging on the first postoperative day, complete removal of the tumour was confirmed in 7 patients. In 2 patients, resection was subtotal due to the fact that part of the tumour that infiltrated eloquent structures was left. In 6 patients, transient neurological deterioration was observed in the early perioperative period, which resolved within 2 months after surgery. In 3 patients, histopathological examination revealed a tumour with a higher grade of malignancy than expected. Conclusions: Our experience confirms that surgical treatment of benign glial tumours using direct electrical stimulation in awake patients is an effective and safe method allowing effective tumour resection with a minimised risk of adverse neurological sequelae.

Preoperative angiographic considerations and neurological outcome after surgical treatment of intradural spinal hemangioblastoma: a multicenter retrospective case series

PurposeIntradural spinal hemangioblastomas are rare highly hypervascularized benign neoplasms. Surgical resection remains the treatment of choice, with a significant risk of postoperative neurological deterioration. Due to the tumor infrequency, scientific evidence is scarce and limited to case reports and small case series.MethodsWe performed a retrospective multicenter study including five high-volume neurosurgical centers analyzing patients surgically treated for spinal hemangioblastomas between 2006 and 2021. We assessed clinical status, surgical data, preoperative angiograms, and embolization when available. Follow-up records were analyzed, and logistic regression performed to assess possible risk factors for neurological deterioration.ResultsWe included 60 patients in Germany and Austria. Preoperative angiography was performed in 30% of the cases; 10% of the patients underwent preoperative embolization. Posterior tumor location and presence of a syrinx favored gross total tumor resection (93.8% vs. 83.3% and 97.1% vs. 84%). Preoperative embolization was not associated with postoperative worsening. The clinical outcome revealed a transient postoperative neurological deterioration in 38.3%, depending on symptom duration and preoperative modified McCormick grading, but patients recovered in most cases until follow-up.ConclusionSpinal hemangioblastoma patients significantly benefit from early surgical treatment with only transient postoperative deterioration and complete recovery until follow-up. The performance of preoperative angiograms remains subject to center disparities.

Radiological and clinical outcomes of stereotactic radiosurgery for gangliogliomas: an international multicenter study.

The optimal treatment for recurrent and residual gangliogliomas remains unclear. The aim of this study was to evaluate the safety and efficacy of stereotactic radiosurgery (SRS) in the management of patients with recurrent or residual intracranial ganglioglioma. This retrospective multicenter study involved patients managed with SRS for ganglioglioma. The study endpoints included local tumor control and tumor- or SRS-related neurological morbidity following treatment. Factors associated with tumor progression and neurological morbidity were also analyzed. The cohort included 20 patients (11 males [55%]) with a median age of 24.5 (IQR 14) years who had been managed with SRS for ganglioglioma. Five-year radiological progression-free survival was 85.6%. After SRS, 2 patients (10%) experienced transient neurological deterioration. At a median clinical follow-up of 88.5 (IQR 112.5) months, 1 patient (5%) experienced seizure worsening and 1 (5%) required further resection of the tumor because of radiological progression. No mortality was noted in this series. SRS appears to be a safe and effective treatment option for surgically inaccessible, recurrent, and residual gangliogliomas. In this series, the 5-year progression-free survival rate after SRS was 85.6%. Gross-total resection remains the primary treatment of choice for patients with newly diagnosed or recurrent ganglioglioma. SRS may be considered for patients unfit for surgery and those with surgically inaccessible newly diagnosed, residual, and recurrent lesions.

Frame-based stereotactic implantation of cystoventricular shunts for treating acquired intracerebral cysts.

The treatment of symptomatic, progressive or recurrent acquired intracerebral cysts is challenging, especially when they are localized in eloquent structures. In addition to resection, endoscopic fenestration, or stereotactic puncture, the implantation of a cystoventricular shunt by stereotactic guidance (SCVS) has been reported as a minimally invasive procedure; however, only scarce data are available regarding its feasibility and efficacy. Here, the authors evaluated the feasibility and efficacy of frame-based SCVS in patients with acquired intracranial cysts. In this single-center retrospective analysis, the authors included all patients with acquired intracerebral cysts treated by SCVS following a standardized prospective protocol between 2012 and 2020. They analyzed clinical symptoms, complications, and radiological outcome with regard to cyst volume reduction by 3D volumetry. Thirty-four patients (17 females and 17 males; median age 44 years, range 5-77 years) were identified. The median initial cyst volume was 11.5 cm3 (range 1.6-71.6 cm3), and the mean follow-up was 20 months (range 1-82 months). At the last follow-up, 27 of 34 patients (79%) showed a cyst volume reduction of more than 50%. Initial symptoms improved or resolved in 74% (n = 25) and remained stable in 24% (n = 8). No permanent clinical deterioration after treatment was observed. The total complication rate was 5.9%, comprising transient neurological deterioration (n = 1) and ventriculitis (n = 1). There were no deaths. The overall recurrence rate was 11.8%. In this study, SCVS proved to be a safe, minimally invasive, and effective treatment with reliable long-term volume reduction, resulting in clinical improvement and a minor complication rate.

Treatment outcomes of 1-stage clipping of multiple unruptured intracranial aneurysms via keyhole approaches.

Complete exclusion of multiple unruptured intracranial aneurysms (UIAs) in one session of intervention may be ideal. However, such situations are not always feasible in terms of treatment modalities and outcomes. The authors aimed to analyze their experience with 1-stage clipping of multiple UIAs. Medical records between March 2013 and December 2018 were retrospectively reviewed, and 111 1-stage keyhole approaches in 110 patients with 261 multiple UIAs were ultimately included in this study. Clinical and radiological outcomes were analyzed, as well as postoperative complications up to 1 month after the surgery and their risk factors. Keyhole approaches included unilateral supraorbital in 87 operations (78.4%), bilateral supraorbital in 12 (10.8%), and others in 12. The mean operative duration was 169.6 minutes (range 80-490 minutes). The highest numbers of aneurysms clipped at once were 2 (73.9%) and 3 (18.9%). Complete exclusion and residual neck of the clipped aneurysms were achieved in 89.3% and 7.3%, respectively. There was no significant difference between pre- and postoperative 1-month neurological states (p = 0.14). The permanent morbidity rate was 1.8% (n = 2), and there were no deaths. Postoperative transient neurological deterioration (TND) with no radiological and electrophysiological abnormalities occurred in 8 operations (7.2%). Hypertension was the only significant risk factor for postoperative TND (adjusted odds ratio 17.03, 95% confidence interval 1.99-2232.24, p = 0.01). One-stage clipping of multiple UIAs via keyhole approaches showed satisfactory treatment outcomes with a low permanent morbidity. Patients with chronic hypertension had a high risk of postoperative TND.

Abstract WMP70: A Novel Hyperspectral Imaging System For Intraoperative Prediction Of Cerebral Hyperperfusion Syndrome After Superficial Temporal Artery-middle Cerebral Artery Anastomosis In Patients With Moyamoya Disease

Background: Postoperative cerebral hyperperfusion syndrome (CHS) may occur after superficial temporal artery (STA)-middle cerebral artery (MCA) bypass for moyamoya disease (MMD). Predicting postoperative CHS is challenging; however, we previously presented the feasibility of using a hyperspectral camera (HSC) for monitoring intraoperative changes in brain surface hemodynamics during STA-MCA bypass. Objective: To investigate the utility of HSC to predict postoperative CHS during STA-MCA bypass for patients with MMD. Methods: Hyperspectral images of the cerebral cortex of twenty nine patients with MMD who underwent STA-MCA bypass were acquired by an HSC before and after anastomosis. We then analyzed the changes in oxygen saturation after anastomosis and assessed its correlation with CHS. Results: Five patients experienced transient neurological deterioration several days after surgery. 123 I-N-isopropyl-iodoamphetamine single-photon emission computed tomography scan results revealed an intense, focal increase in cerebral blood flow (CBF) at the site of anastomosis without any cerebral infarction. Patients with CHS showed significantly increased oxygen saturation (SO 2 ) in the cerebral cortex after anastomosis relative to those without CHS (33 ± 28% vs. 8 ± 14%, P&lt;.0001). Receiver operating characteristic analysis results show that postoperative CHS likely occurs when the increase rate of cortical SO 2 value is more than 15% (sensitivity, 85.0%; specificity, 81.3%; area under curve, 0.871). Conclusions: This study indicates that hyperspectral imaging of the cerebral cortex may be used to predict postoperative CHS in patients with MMD undergoing STA-MCA bypass.

Surgical treatment of herniated thoracic discs using transthoracic extrapleural approach

To analyze the results of herniated thoracic disc resection via transthoracic extrapleural approach. The study included 16 patients with 18 symptomatic herniated thoracic discs wo underwent transthoracic extrapleural surgery. In 11 cases, clinical pattern of disease was represented by myelopathy with radicular or axial pain syndrome. Five patients had radiculopathy alone. Median localization of hernias was observed in 8 (44.4%) cases, paramedian hernias - in 10 (55.6%) cases. There were 10 (55.6%) ossified hernias, 5 (27.7%) giant, 10 (55.5%) large and 3 (16.6%) medium hernias. In most patients, VAS score of pain syndrome decreased by 2-6 points (mean 3.6). In 4 patients, this value remained the same. Among 11 patients with myelopathy, regression of conduction disorders in 1 year after surgery was achieved in 9 (82%) cases including complete recovery in 6 (55%) patients (Frankel E, Nurick - 0-I). In 2 patients, neurological status was equal to preoperative one. In all cases, the follow-up examination confirmed total removal of compressive substrate and found no signs of spine instability. Surgery time varied from 80 to 210 min (mean 161), blood loss - from 300 to 800 ml (mean 378 ml). Two patients had transient neurological deterioration. There was damage to dura mater in 4 cases. Intercostal neuralgia was observed in 3 patients. While retaining the advantages of open thoracotomy, transthoracic extrapleural approach is less traumatic, allows complete spinal cord decompression, minimizes the risk of iatrogenic spinal cord injury and avoids certain postoperative complications.

Rediscovery of the transcerebellar approach: improving the risk-benefit ratio in robot-assisted brainstem biopsies.

Conventional frame-based stereotaxy through a transfrontal approach (TFA) is the gold standard in brainstem biopsies. Because of the high surgical morbidity and limited impact on therapy, brainstem biopsies are controversial. The introduction of robot-assisted stereotaxy potentially improves the risk-benefit ratio by simplifying a transcerebellar approach (TCA). The aim of this single-center cohort study was to evaluate the risk-benefit ratio of transcerebellar brainstem biopsies performed by 2 different robotic systems. In addition to standard quality indicators, a special focus was set on trajectory selection for reducing surgical morbidity. This study included 25 pediatric (n = 7) and adult (n = 18) patients who underwent 26 robot-assisted biopsies via a TCA. The diagnostic yield, complication rate, trajectory characteristics (i.e., length, anatomical entry, and target-point location), and skin-to-skin (STS) time were evaluated. Transcerebellar and hypothetical transfrontal trajectories were reconstructed and transferred into a common MR space for further comparison with anatomical atlases. Robot-assisted, transcerebellar biopsies demonstrated a high diagnostic yield (96.2%) while exerting no surgical mortality and no permanent morbidity in both pediatric and adult patients. Only 3.8% of cases involved a transient neurological deterioration. Transcerebellar trajectories had a length of 48.4 ± 7.3 mm using a wide stereotactic corridor via crus I or II of the cerebellum and the middle cerebellar peduncle. The mean STS time was 49.5 ± 23.7 minutes and differed significantly between the robotic systems (p = 0.017). The TFA was characterized by longer trajectories (107.4 ± 11.8 mm, p < 0.001) and affected multiple eloquent structures. Transfrontal target points were located significantly more medial (-3.4 ± 7.2 mm, p = 0.042) and anterior (-3.9 ± 8.4 mm, p = 0.048) in comparison with the transcerebellar trajectories. Robot-assisted, transcerebellar stereotaxy can improve the risk-benefit ratio of brainstem biopsies by avoiding the restrictions of a TFA and conventional frame-based stereotaxy. Profound registration and anatomical-functional trajectory selection were essential to reduce mortality and morbidity.

Transient Global Cerebral Hypoperfusion as a Characteristic Cerebral Hemodynamic Pattern in the Acute Stage after Combined Revascularization Surgery for Pediatric Moyamoya Disease: N-Isopropyl-P-[123I] Iodoamphetamine Single-Photon Emission Computed Tomography Study

Introduction: Surgical revascularization prevents cerebral ischemic attack by improving cerebral blood flow (CBF) in both adult and pediatric patients with moyamoya disease (MMD). Uneven hemodynamic changes, including local cerebral hyperperfusion and remote ischemia, can cause delayed intracerebral hemorrhage and perioperative infarctions in adult MMD patients, but the characteristic hemodynamic pattern among pediatric MMD patients after revascularization surgery is poorly understood. Methods: This study included 16 consecutive pediatric MMD patients (age, 6–16 years; mean age, 11.3) undergoing superficial temporal artery-middle cerebral artery anastomosis combined with encephalo-duro-myo-synangiosis on 21 affected hemispheres. Perioperative management was conducted by aspirin administration and strict blood pressure control (110–130 mm Hg). We prospectively performed N-isopropyl-p-[¹²³I] iodoamphetamine single-photon emission computed tomography on postoperative days (POD) 1 and 7 and analyzed the temporal changes in perioperative hemodynamics. Results: Four patients (19.0%, 4/21) exhibited immediate CBF improvement from POD 1, which was classified as “immediate redistribution pattern.” In contrast, 9 (42.9%, 9/21) demonstrated transient hemispheric global hypoperfusion at POD 1 and subsequent CBF improvement at POD 7, which was defined as “transient hypoperfusion pattern.” Although 8 patients, including 4 with “transient hypoperfusion pattern” (44.4, 4/9), developed mild transient neurological deterioration in the acute stage, it resolved in all 21 patients, and there were no permanent neurological deficits. Discussion/Conclusions: This study revealed that the “transient hypoperfusion pattern” after revascularization surgery is relatively common among pediatric MMD patients, and its outcome is favorable under strict perioperative management.

Surgical Treatment and Clinical Outcomes of Petroclival Meningiomas: A Single-Center Experience of 107 Patients.

ObjectiveThis study aimed to establish optimal surgical strategies via reviewing the clinical outcomes of various surgical approaches for the pertroclival meningiomas (PCMs).MethodsThis retrospective study enrolled 107 patients with PCMs at the authors’ institution from year 2010 to 2020. Patient demographics, the clinical characteristics, various operative approaches, major morbidity, post-operative cranial nerve deficits and tumor progression or recurrence were analyzed.ResultsThe subtemporal transtentorial approach (STA), the Kawase approach (KA), the retrosigmoid approach (RSA) and the anterior sigmoid approach (ASA), namely the posterior petrosal approach (PPA) were adopted for 17 cases, 22 cases, 31 cases and 34 cases respectively. Total or subtotal resection was achieved in 96 cases (89.7%). The incidence of new-onset and aggravated cranial nerve dysfunction were 13.1% (14/107) and 10.4% (15/144), respectively. Furthermore, 14 cases suffered from intracranial infection, 9 cases had cerebrospinal fluid leakage, and 3 cases sustained intracranial hematoma (1 case underwent second operation). The mean preoperative and postoperative Karnofsky Performance Status (KPS) score was 80 (range 60-100) and 78.6 (range 0-100), but this was not statistically significant (P>0.05). After a mean follow-up of 5.1 years (range 0.3- 10.6 years), tumor progression or recurrence was confirmed in 23 cases. Two cases died from postoperative complications.ConclusionsFor the treatment of PCMs, it is still a challenge to achieve total resection. With elaborate surgical plans and advanced microsurgical skills, most patients with PCMs can be rendered tumor resection with satisfactory extent and functional preservation, despite transient neurological deterioration during early postoperative periods.

The clinical effect of ultrasonic bone curette-assisted "zoning" style laminectomy for the treatment of severe ossification of thoracic ligamentum flavum

Objective: To investigate the safety and clinical efficacy of "zoning" style laminectomy by ultrasonic bone curette in patients with severe thoracic ossification of the ligamentum flavum(TOLF). Methods: The clinical data of 36 patients with severe TOLF treated by "zoning" style laminectomy at Department of Spinal Surgery,Zhengzhou Orthopaedic Hospital from October 2015 to October 2018 were respectively analyzed.There were 17 males and 19 females,aged(57.3±10.2)years(range:43 to 80 years).According to the anatomical characteristics of the thoracic ligamentum flavum and the pathological process of ossionization,each decompression segment was divided into the upper 1/3 area of the lamina,the bilateral area of the ossionum flavum,the transitional area,and the area of close contact between the ossionum flavum and the spinal cord.Different surgical strategies were used for decompression in turn.The modified Japanese Orthopedic Association (mJOA) was used to evaluate the neurological function status before and after surgery,to evaluate the surgical effect of patients,and to observe the surgical complications.Paired sample T test was used for data analysis. Results: All 36 patients successfully completed the operation,the operation time was (88.6±24.6) minutes(range:60 to 150 minutes).The intraoperative blood loss was (426.7±167.4) ml(range:250 to 800 ml).Follow-up time was (27.2±7.7) months(range:12 to 48 months).The mJOA score at the last follow-up was 9.0±1.5,which was statistically significant compared with the preoperative score 5.4±1.8 (t=13.59,P<0.01).The improvement rate of mJOA score was (65.7±22.1) %,of which 17 cases were excellent (47.2%),13 cases were good (36.1%),4 cases were normal (11.1%),2 cases were ineffective (5.6%).Ten patients had cerebrospinal fluid leakage during the separation or removal of dural ossification and were cured after a series of comprehensive conservative treatment.Two patients showed transient neurological deterioration,and the neurological function gradually recovered to the preoperative state after comprehensive treatment such as increasing the mean arterial pressure and using neurotrophic drugs.During the follow-up,no aggravation of neurological dysfunction and segmental kyphosis were found. Conclusions: The ultrasonic bone curette-assisted "zoning" style laminectomy for the treatment of severe TOLF can directly observed the position relationship between ossification of the ligamentum flavum and the spinal canal structure during the operation,and accurately guide the surgical decompression.It has the advantages of safe operation and complete decompression,which provides an important reference for the selection of clinical surgery.

Comparing the clinical presentation and outcomes of dogs receiving medical or surgical treatment for osseous-associated cervical spondylomyelopathy.

This study aimed to compare the clinical presentation, short and long term outcomes of dogs treated surgically or medically for Osseous associated cervical spondylomyelopathy. Information collected retrospectively from medical records included signalment, neurological status and treatment type. Surgical treatment consisted of dorsal laminectomy. Medical treatment involved restricted exercise and medication. Improvement or deterioration in neurological status was determined at discharge, re-examination 4-8weeks post-treatment and by telephone interview with the referring veterinary surgeon or owner at the time of the study, which ranged from 8-54 months following the discharge (median, 16 months). Twenty-four dogs were treated surgically and 30 medically. Neurological grade at clinical presentation was significantly higher in surgically treated dogs (p=0.004). Transient early postoperative neurological deterioration occurred in 73.1% of surgically treated dogs. For medical cases, long term improvement was seen in 15% of cases, remained static in 40% and deterioration in 45%. Surgical treatment resulted in long term improvement in 67% of cases, remained static in 29% and deterioration in 4% of cases. This study suggests that surgery is a favourable treatment option, however, requires intensive post-operative care. Medical treatment was associated with a guarded prognosis but could be a viable treatment option for selected dogs.

Comparison of Surgical Outcomes Between Staged and Simultaneous Decompression of Discontinuous Thoracic Ossification of the Ligamentum Flavum: A Retrospective Study

Discontinuous thoracic ossification of the ligamentum flavum (TOLF) is diagnosed according to the number and distribution of involved segments seen on magnetic resonance images. When TOLF causes thoracic myelopathy, surgical intervention for these lesions becomes unavoidable. However, there are few reports on the outcomes of surgery for discontinuous TOLF. The study included 26 patients of mean age 55.0 years who underwent simultaneous (n= 16) or staged (n= 10) decompression of discontinuous TOLF between July 2006 and June 2016. Final neurologic status was evaluated using the modified Japanese Orthopaedic Association (JOA) score. The surgical data and incidence ofcomplications were compared. The mean follow-up duration was 73.3 months. There was no between-group difference in number of levels decompressed or the amount of intraoperative blood loss. There was a significant improvement in the JOA score from 4.0 before surgery to 8.0 postoperatively, with an average recovery rate of 58.3%. The JOA recovery rate was significantly better in the staged group than simultaneous group (68.4% vs. 52.0%, P < 0.05). However, the incidence of complications was similar between the staged and simultaneous groups including for dural tear (1 vs. 6, P= 0.19), cerebrospinal fluid leak (4 vs. 6, P= 1.00), and transient neurologic deterioration (0 vs. 2, P= 0.51). The surgical outcome of staged decompression for discontinuous TOLF seems to be better than that of simultaneous decompression. The complication rates of these 2 strategies are similar.

Blood Pressure and Transient Postoperative Neurologic Deterioration, Following Superficial Temporal-to-Middle Cerebral Artery Anastomosis in Adult Patients with Moyamoya Disease: A Retrospective Cohort Study.

We investigated whether intraoperative systolic blood pressure (ISBP) is associated with the risk of transient neurologic deficits (TND) following superficial temporal-to-middle cerebral artery (STA-MCA) anastomosis in adult patients with moyamoya disease (MMD). In this retrospective observational study, data from adult patients with MMD who had undergone STA-MCA anastomosis at a single tertiary academic hospital during May 2003–April 2014 were examined. Data on patient characteristics were obtained from electronic medical records, including the details of comorbidities and laboratory findings. TND was the primary outcome of interest. Out of 192 patients (228 hemispheres), 66 (29%) hemispheres had TND after surgery. There were significant differences in ISBP between patients with and without TND. The lowest ISBP quartile was independently associated with TND (odds ratio: 5.50; 95% confidence interval: 1.96–15.46). Low ISBP might lead to TND after STA-MCA anastomosis in adult patients with MMD. In patients with poor perfusion status, low ISBP was associated with an increased risk of TND. Our findings suggest that strict ISBP control might be required to prevent TND after anastomosis in patients with MMD, in particular, in patients with poor perfusion status. Given limitations due to the retrospective design, further studies are needed to clarify these findings.

A Novel Hyperspectral Imaging System for Intraoperative Prediction of Cerebral Hyperperfusion Syndrome after Superficial Temporal Artery-Middle Cerebral Artery Anastomosis in Patients with Moyamoya Disease

Background: Postoperative cerebral hyperperfusion syndrome (CHS) may occur after superficial temporal artery (STA)-middle cerebral artery (MCA) bypass for moyamoya disease (MMD). Predicting postoperative CHS is challenging; however, we previously reported the feasibility of using a hyperspectral camera (HSC) for monitoring intraoperative changes in brain surface hemodynamics during STA-MCA bypass. Objective: To investigate the utility of HSC to predict postoperative CHS during STA-MCA bypass for patients with MMD. Methods: Hyperspectral images of the cerebral cortex of 29 patients with MMD who underwent STA-MCA bypass were acquired by using an HSC before and after anastomosis. We then analyzed the changes in oxygen saturation after anastomosis and assessed its correlation with CHS. Results: Five patients experienced transient neurological deterioration several days after surgery. ¹²³I-N-Isopropyl-iodoamphetamine single-photon emission computed tomography scan results revealed an intense, focal increase in cerebral blood flow at the site of anastomosis without any cerebral infarction. Patients with CHS showed significantly increased oxygen saturation (SO₂) in the cerebral cortex after anastomosis relative to those without CHS (33 ± 28 vs. 8 ± 14%, p < 0.0001). Receiver operating characteristic analysis results show that postoperative CHS likely occurs when the increase rate of cortical SO₂ value is >15% (sensitivity, 85.0%; specificity, 81.3%; area under curve, 0.871). Conclusions: This study indicates that hyperspectral imaging of the cerebral cortex may be used to predict postoperative CHS in patients with MMD undergoing STA-MCA bypass.

Can safe and radical resection of all types of parasagittal meningiomas be achievable? —the introduction of a simplified surgical strategy

ABSTRACT Background: Surgery of parasagittal meningiomas (PSMs) is still technically challenging, for the balance between radical resection and preservation of venous circulation. In this article, we’d systemically introduce the technical nuances of a simplified strategy for radical resection of all types of PSMs. All the cases were operated by one single neurosurgeon from a single institution. Methods: Clinical charts of patients with PSMs between 2014 and 2020were retrospectively reviewed. A simplified classification method was adopted, which was based on the relationship between the tumor and superior sagittal sinus (SSS). Surgery aiming at radical resection and venous flow preservation was performed. Only in case of total occlusion of SSS, we performed tumor resection without reconstruction of the venous sinus. Results: Clinical data obtained in 55 consecutive patients (47 primary and 8 recurrent cases) were analyzed, among which 20 were with patent sinus, 27 were with partially occluded sinus and 8 were with completely occluded sinus. Forty-two (76.4%) and 13 patients (23.6%) had the same and improved functional status as compared to that of pre-operation, respectively. Four patients (7.3%) experienced transient neurological deterioration but improved to the normal level in the long-term follow-up. All patients achieved Simpson I/II radical resection. No patients suffered from post-operative recurrence in the follow-up duration of 27.05 ± 19.55 (2–91) months. Conclusion: Radical and safe resection of all types of PSMs is achievable and not difficult if the simplified surgical strategy mentioned in the article is adopted, no matter to which extent the sinus is invaded.

CTIM-16. INTERSTITIAL PHOTODYNAMIC THERAPY WITH 5-ALA FOR MALIGNANT GLIOMA RECURRENCES

Abstract Interstitial photodynamic therapy (iPDT) using 5-aminolevulinic acid (5-ALA) induced protoporphyrin IX (PPIX) as a cytotoxic photosensitizer has been shown to be a feasible treatment option for malignant gliomas. We present outcome measures and a risk profile analysis of salvage iPDT in a large monocentric cohort with local tumor recurrence following standard therapy. This study included consecutive adult patients undergoing salvage iPDT for small, circumscribed, biopsy-proven malignant glioma recurrences not deemed eligible for safe complete resection of contrast enhancing tumor. A modified 3-D treatment-planning software was used to calculate the treatment-volume and the position of the stereotactic light diffusers within the lesion. Outcome measurements included estimated time-to-treatment-failure (TTF), post-recurrence survival (PRS) and the risk profile of iPDT. Prognostic factors were obtained from logistic regression models. The institutional review board approved the study. A total of 44 patients (median age: 49.4 years, range 33.4–87.0 years, 17 female) were included. Recurrent tumors included 37/44 glioblastomas WHO grade IV and 7/44 anaplastic astrocytomas WHO grade III. Thirty (68.2%) tumors were MGMT methylated. Median treatment volume was 3.3 ccm (range, 0.5–22.8 ccm). A median number of 4 (range: 3–8) laser fibers were used. Median illumination time was 60min (range: 60–167 min). Symptomatic edema (8/44) or intratumoral hemorrhagic imbibition (7/44) did not result in any permanent morbidity. Median TTF was 7.1 months and median PRS was 13.0 months. The 2- and 5-years PRS rates were 25.0% and 4.5%. Treatment response was heterogeneous and not significantly associated with patient characteristics, treatment-related factors or molecular markers. In conclusion, iPDT was associated with promising outcome measurements in local malignant glioma recurrences in highly selected patients. Transient neurologic deterioration did not lead to any permanent morbidity. The procedure deserves further prospective evaluation particularly to identify mechanisms of favorable treatment response and prognostic factors associated with long-term survival.

Posterior transdural resection of giant calcified thoracic disc herniation in a case series of 12 patients

Calcified thoracic disc herniations present a rare and challenging entity. Due to the close proximity to the spinal cord and relative narrowing of the spinal canal, the optimal approach remains a matter of debate. While the transthoracic approach is usually preferred, we adapted a new technique described in 2012: the transdural posterior approach. Our aim was to evaluate its benefits in patients with giant thoracic disc protrusions. We retrospectively reviewed all patients treated in our neurosurgical department from July 2012 to March 2020. Demographics, pre- and postoperative clinical status, and operative technique and complications were extracted and analyzed. In total, 12 patients underwent a posterior transdural resection of giant calcified thoracic hard discs between 2012 and 2020. All patients underwent a posterior decompression (laminectomy, hemilaminectomy, or laminoplasty). The median duration of surgery was 152 min. Transient postoperative neurological deterioration occurred in 4 patients, with complete recovery until time of discharge. No patient underwent a surgical revision. The transdural resection of giant calcified thoracic hard discs through a posterior approach provides an excellent decompression with sufficient visualization of the spinal cord and a satisfying postoperative outcome.