Contributing factors of spontaneous intracerebral hemorrhage development in young adults.

Objective: The incidence of spontaneous intracerebral hemorrhage (ICH) in young people is relatively low; however, it leads to devastating lifelong neurologic deficits. We focused on spontaneous ICH occurring in young adults between 30 and 50 years of age. Methods: We retrospectively reviewed the records of 139 patients, aged 30-50 years, diagnosed with spontaneous ICH between 2011 and 2021. Cases of ICH attributable to discernible causative lesions were excluded. Demographic data, laboratory results, image findings, and clinical outcome were analyzed. Results: After exclusions, 73 patients were included in this study. Common characteristics among the study patients included male sex (83.6%), high body mass index (>25 kg/m2, 45.8%), smoking history (47.2%), heavy alcohol consumption (30.6%), previously diagnosed hypertension (41.1%), high serum triglyceride level (>150 mg/dL, 33.3%), and microbleeds or white matter changes observed on magnetic resonance images (51.3%). In the multivariate analysis, previously diagnosed hypertension was the sole significant risk factor for cerebral small vessel (OR 7.769, P=0.031). Age, brain stem location, Glasgow Coma Scale score at admission, and hematoma volume were associated with poor outcomes. Conclusions: Hypertension, obesity, smoking, and cerebral small vessel disease were important factors associated with non-lesional spontaneous intracerebral hemorrhage in young patients. Radiologic changes corresponding to cerebral small vessel disease appeared in young patients (in their 30s) and they were associated with hypertension.

Clinical impact of craniectomy on shunt-dependent hydrocephalus after intracerebral hemorrhage: A propensity score-matched analysis.

PURPOSE: A consensus on decompressive craniectomy for intracerebral hemorrhage (ICH) has not yet been established. We aimed to investigate the development of shunt-dependent hydrocephalus based on the method of ICH surgery, with a focus on craniectomy. METHODS: We retrospectively enrolled 458 patients with supratentorial ICH who underwent surgical hematoma evacuation between April 2005 and December 2021 at two independent stroke centers. Multivariate analyses were performed to characterize risk factors for postoperative shunt-dependent hydrocephalus. Propensity score matching (1:2) was undertaken to compensate for group-wise imbalances based on probable factors that were suspected to affect the development of hydrocephalus, and the clinical impact of craniectomy on shunt-dependent hydrocephalus was evaluated by the matched analysis. RESULTS: Overall, 43 of the 458 participants (9.4%) underwent shunt procedures as part of the management of hydrocephalus after ICH. Multivariate analysis revealed that intraventricular hemorrhage (IVH) and craniectomy were associated with shunt-dependent hydrocephalus after surgery for ICH. After propensity score matching, there were no statistically significant intergroup differences in participant age, sex, hypertension status, diabetes mellitus status, lesion location, ICH volume, IVH occurrence, or IVH severity. The craniectomy group had a significantly higher incidence of shunt-dependent hydrocephalus than the non-craniectomy group (28.9% vs. 4.3%, p < 0.001; OR 9.1, 95% CI 3.7-22.7), craniotomy group (23.2% vs. 4.3%, p < 0.001; OR 6.6, 95% CI 2.5-17.1), and catheterization group (20.0% vs. 4.0%, p = 0.012; OR 6.0, 95% CI 1.7-21.3). CONCLUSION: Decompressive craniectomy seems to increase shunt-dependent hydrocephalus among patients undergoing surgical ICH evacuation. The decision to perform a craniectomy for patients with ICH should be carefully individualized while considering the risk of hydrocephalus.

Parallel Analysis of Pre- and Postoperative Circulating Tumor DNA and Matched Tumor Tissues in Resectable Pancreatic Ductal Adenocarcinoma: A Prospective Cohort Study.

BACKGROUND: Circulating tumor DNA (ctDNA) is a promising biomarker for early tumor detection and minimal residual disease (MRD) assessment in early-stage cancer, but quantifying minute amounts of ctDNA is challenging and well-designed studies on ctDNA in early-stage cancer are still lacking. Here, we adapted a sensitive next-generation sequencing (NGS) technology and performed parallel analysis of pre- and postoperative ctDNA and matched tumor tissues in a prospective cohort of patients with resectable pancreatic ductal adenocarcinoma (PDAC). METHODS: In total, 70 consecutive patients undergoing curative resection for resectable PDAC were enrolled. We performed integrated digital error suppression-enhanced cancer personalized profiling by deep sequencing NGS of triple-matched samples (pre/postoperative plasma cell-free DNA [cfDNA], tumor tissue, and genomic DNA) targeting 77 genes. RESULTS: Preoperative ctDNA was detected in 37.7% of the evaluable patients, with a median variant allele frequency of 0.09%. Twelve additional oncogenic mutations were detected exclusively in preoperative ctDNA but not in tissue. When quantitative concentrations of ctDNA were estimated in haploid genome equivalents per milliliter (hGE/mL), the risk of early recurrence was high in patients with postoperative ctDNA >1 hGE/mL. cfDNA variants from 24.5% of patients had features compatible with clonal hematopoiesis. CONCLUSIONS: An optimized NGS approach might add value beyond tissue analysis through the highly sensitive detection of minute amounts of ctDNA in resectable PDAC. Postoperative ctDNA concentration could be a tool for MRD assessment. Moreover, parallel analyses of matched tissues and leukocytes might be required to accurately detect clinically relevant ctDNA.

Prediction of Shunt-Dependent Hydrocephalus after Primary Supratentorial Intracerebral Hemorrhage with a Focus on the Influence of Craniectomies.

OBJECTIVE: Hydrocephalus after intracerebral hemorrhage (ICH) is known to be related to poor prognosis and mortality. We analyzed predictors of permanent hydrocephalus in the patients with surgically treated supratentorial ICH. METHODS: From 2004 to 2019, a total of 414 patients with surgically treated primary supratentorial ICH were included. We retrospectively analyzed age, sex, preexisting hypertension and diabetes, location and volume of ICH, presence and severity of intraventricular hemorrhage (IVH), and type of surgery. RESULTS: Forty patients (9.7%) required shunt surgery. Concomitant IVH was higher in the 'shunt required' group (92.5%) than in the 'shunt not required' group (67.9%) (p=0.001). IVH severity was worse in the 'shunt required' group (13.5 vs. 7.5, p=0.008). Craniectomy (47.5%) was significantly high in the 'shunt required' group. According to multivariable analysis, the presence of an IVH was 8.1 times more frequent and craniectomy was 8.6 times more frequent in the 'shunt required' group. In the comparison between craniotomy and craniectomy group, the presence of an IVH was related with a 3.9 times higher (p=0.033) possibility and craniectomies rather than craniotomies with a 7-times higher possibility of shunt surgery (p<0.001). Within the craniectomy group, an increase in the craniectomy area by 1 cm2 was correlated with a 3.2% increase in the possibility of shunt surgery (odds ratio, 1.032; 95% confidence interval, 1.005-1.061; p=0.022). CONCLUSION: Presence of IVH, the severity of IVH and decompressive craniectomy were related to the development of shunt dependent hydrocephalus in the patients with ICH. The increasing size of craniectomy was related with increasing rate of shunt requirement.

Clinical Utility of Methylation-Specific Multiplex Ligation-Dependent Probe Amplification for the Diagnosis of Prader-Willi Syndrome and Angelman Syndrome.

BACKGROUND: Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are genomic imprinting disorders that are mainly caused by a deletion on 15q11-q13, the uniparental disomy of chromosome 15, or an imprinting defect. We evaluated the utility of methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) as a diagnostic tool and for demonstrating the relationship between molecular mechanisms and clinical presentation. METHODS: We performed MS-MLPA using DNA samples from 93 subjects (45 PWS, 24 AS, and 24 non-PWS/AS controls) who had previously undergone MS-PCR for the diagnosis of PWS/AS. We compared the results of both assays, and patients' clinical phenotypes were reviewed retrospectively. RESULTS: MS-MLPA showed a 100% concordance rate with MS-PCR. Among the 45 PWS patients, 26 (57.8%) had a deletion of 15q11-q13, and the others (42.2%) had uniparental disomy 15 or an imprinting defect. Among the 24 AS patients, 16 (66.7%) had a deletion of 15q11-q13, 7 AS patients (29.2%) had uniparental disomy 15 or an imprinting defect, and one AS patient (4.2%) showed an imprinting center deletion. CONCLUSIONS: MS-MLPA has clinical utility for the diagnosis of PWS/AS, and it is superior to MS-PCR in that it can identify the molecular mechanism underlying the disease.

Growth profile assessment of young adults with tethered cord syndrome: a retrospective cohort analysis of Korean conscription data.

PURPOSE: Tethered cord syndrome (TCS) is characterized by progressive spinal cord degeneration secondary to congenital spinal dysraphism. The associated accompanying physical inactivity and musculoskeletal deformities have raised interest in the growth profile of adult TCS patients. However, few previous studies have investigated the growth profile of adult TCS patients. METHODS: We retrospectively reviewed the demographic data and medical records of 20-year-old Korean conscription examinees who were registered between April 2004 and September 2019. In total, 151 examinees with a diagnosis of TCS were enrolled. The height, weight, and body mass index (BMI) of 300 randomly selected examinees were compared to the TCS group. Obesity was defined by the World Health Organization and Asian-Pacific criteria for BMI and compared between the groups. Growth profile differences according to tethering location and musculoskeletal deformities were analyzed in both groups. RESULTS: The mean height, weight, and BMI values of the TCS group were lower than those of the control group. The TCS group had a lower proportion of obese and overweight individuals, and a higher proportion of underweight individuals, according to both BMI criteria. The tethering level was not associated with the degree of obesity in the tethered group. The mean height, weight, and BMI were lower in the tethered group regardless of the existence of musculoskeletal deformity. CONCLUSION: Enrollees with a history of TCS were smaller than controls of the same age. Monitoring of health behaviors, including nutrition, diet, and exercise, is warranted for TCS patients.

Impact of adolescent complex regional pain syndrome on the psychopathology of young men ahead of military service: a retrospective cohort analysis of Korean conscription data.

BACKGROUND: The relationship between physical and psychopathological features in complex regional pain syndrome (CRPS) has been a subject of constant interest, but no data are available in adolescents. Therefore, we aimed to identify the factors associated with psychopathology in adolescents with CRPS ahead of military service. METHODS: We retrospectively reviewed all conscription examinees who had completed a Military Personality Inventory (MPI) during a period between February 2013 and December 2016. A total of 63 persons with a history of CRPS (19-years of age for all) were enrolled. Basic demographic and pain-related data were analyzed to examine their association with MPI results. The mean FGR score as well as the 8 subdomain scores were compared between those with pain duration at < 15 months (n = 30) versus ≥15 months (n = 33). Binary MPI results (normal-abnormal) were also compared between the two groups. RESULTS: In multivariate analysis, abnormal MPI was associated with pain duration, with an odds ratio (OR) at 1.05 for every 1-month increase (95% confidence interval (CI) 1.02-1.08; P = 0.002). Subjects with pain duration at ≥15 months have lower faking good response score (P < 0.001 vs. those with pain duration at < 15 months), and higher abnormal MPI result rate, faking bad response, inconsistency, anxiety, depression, somatization, paranoid, personality disorder cluster A, and personality disorder cluster B scores (P < 0.05). Pain duration was significantly associated with the MPI variables. CONCLUSIONS: Pain duration is associated with psychopathology in adolescents with CRPS. Psychopathologic features increased as the disease duration increased. A comprehensive understanding of time-dependent psychopathological factors could support the planning of multimodal approaches for managing adolescent CRPS.

Comparison of Postoperative Surgical-Site Infection and Symptomatic Intracranial Hemorrhage between Staged and Simultaneous Cranioplasty with Ventriculoperitoneal Shunt Placement: A Meta-Analysis.

OBJECTIVE: Consensus about the sequence of cranioplasty and ventriculoperitoneal shunt placement to reduce postoperative complications has not been established. This meta-analysis investigated and collated further evidence to determine whether staged cranioplasty with ventriculoperitoneal shunt placement would significantly reduce the risk of postoperative surgical-site infection (SSI) and symptomatic intracranial hemorrhage. METHODS: Two independent reviewers identified articles and extracted the data of patients who underwent cranioplasty and ventriculoperitoneal shunt placement from PubMed, Embase, and Cochrane Central Register of Controlled Trials. A random effects model was used to compare the complication rates using odd ratios (ORs) and 95% confidence intervals (CIs). A meta-regression analysis for traumatic brain injury (TBI) was additionally performed. RESULTS: Data from 7 studies with 391 patients were consecutively included. The meta-analysis revealed that staged surgery was significantly associated with lower rates of SSI after decompressive craniectomy (staged group vs. simultaneous group: 6.2% vs. 23.7%, OR: 2.72, 95% CI: 1.46-5.06, I2=2.4%, p=0.407). Pooled analysis did not indicate a statistically significant difference between the 2 groups for symptomatic intracranial hemorrhage (staged group vs. simultaneous group: 10.4% vs. 23.0%, OR: 1.66, 95% CI: 0.74-3.73, I2=0.0%, p=0.407). The meta-regression analysis did not indicate any modifying effect of TBI on postoperative SSI development (p=0.987). CONCLUSION: This meta-analysis indicated that staged surgery is significantly associated with a lower rate of postoperative SSI as compared with simultaneous surgery, but there is no difference in symptomatic intracranial hemorrhage. Additionally, there is no modifying effect of TBI on SSI.

Relationship between Increased Intracranial Pressure and Mastoid Effusion.

OBJECTIVE: This study aimed to assess the relationship between increased intracranial pressure (ICP) and mastoid effusions (ME). METHODS: Between January 2015 and October 2018, patients who underwent intracranial surgery and had ICP monitoring catheters placed were enrolled. ICP was recorded hourly for at least 3 days. ME was determined by the emergence of opacification in mastoid air cells on follow-up brain imaging. C-reactive protein (CRP) levels, presence of endotracheal tube (ETT) and nasogastric tube (NGT), duration of intensive care unit (ICU) stay, duration of mechanical ventilator application, diagnosis, surgical modalities, and presence of sinusitis were recorded. Each factor's effect on the occurrence of ME was analyzed by binary logistic regression analyses. To analyze the independent effects of ICP as a predictor of ME a multivariable logistic regression analysis was performed. RESULTS: Total of 61 (53%) out of 115 patients had ME. Among the patients who had unilateral brain lesions, 94% of subject (43/50) revealed the ipsilateral development of ME. ME developed at a mean of 11.1±6.2 days. The variables including mean ICP, peak ICP, age, trauma, CRP, ICU stays, application of mechanical ventilators and presence of ETT and NGT showed statistically significant difference between ME groups and non-ME groups in univariate analysis. Sex and the occurrence of sinusitis did not differ between two groups. Adding the ICP variables significantly improved the prediction of ME in multivariable logistic regression analysis. CONCLUSION: While multiple factors affect ME, this study demonstrates that ICP and ME are probably related. Further studies are needed to determine the mechanistic relationship between ICP and middle ear pressure.

Psychopathological Influence of Middle Fossa Arachnoid Cysts in Young Men: Analysis of Korean Conscription Data.

BACKGROUND: A few reported studies have documented psychotic syndromes secondary to a middle fossa arachnoid cyst (AC). However, the association between middle fossa ACs and psychopathological symptoms remains to be determined. The present study investigated the psychopathological effects of middle fossa ACs in young men. METHODS: We reviewed military personal inventory test profiles and baseline demographic data of 19-year-old conscription examinees from February 2013 to December 2016. In total, 132 examinees with middle fossa ACs and 350 examinees with normal findings were enrolled in the present study. Two separate comparisons were performed. First, we compared the middle fossa AC group with the control group. Second, the middle fossa AC group was divided into 2 groups according to cyst size and compared with the control group. RESULTS: Faking bad response behavior, infrequency, inconsistency, depression, schizophrenia, paranoia, and personality disorder cluster A scales were significantly associated with the presence of a middle fossa AC. Abnormal responses to the military personal inventory were significantly and positively correlated with cyst size. The prediction rate to show abnormal psychological results with the presence of an AC was estimated to be 60.7%-68.8%. CONCLUSIONS: The presence of ACs and cyst size were associated with psychopathology in this select group of young men. The size-dependent psychopathological effects of ACs appear to result from a local mass effect on the brain.

Four-year follow-up results of magnetic resonance-guided focused ultrasound thalamotomy for essential tremor.

BACKGROUND: Following the emergence of magnetic resonance-guided focused ultrasound as a promising tool for movement disorder surgery, thalamotomy for essential tremor using this technique has become a useful tool based on its efficacy and lack of adverse effects. Here, we summarize the 4-year results of previous reports focusing on the durability of effectiveness of magnetic resonance-guided focused ultrasound thalamotomy for essential tremor. METHODS: From October 2013 to August 2014, 15 patients with intractable essential tremor were enrolled. Twelve of them completed clinical assessment through 4 years of postoperative follow-up. Tremor severity, task performance, and disability were measured using the Clinical Rating Scale of Tremor. RESULTS: The mean age of the 12 patients was 61.7 ± 8.1 years. Maximally delivered energy was 15,552.4 ± 6574.1 joules. The mean number of sonications was 17.3 ± 1.6. The mean postoperative lesion volume was 82.6 ± 29.023 mm3 and in 1 year was a mean of 9.667 ± 8.573 mm3 . Four years postoperatively, improvement of the hand tremor score was 56%, that of the disability score was 63%, that of the postural score was 70%, and that of the action score was 63% compared with baseline; all improvements were significant and sustained over the 4-year period after thalamotomy. There was no permanent adverse effect throughout the 4-year follow-up period. CONCLUSIONS: Magnetic resonance-guided focused ultrasound thalamotomy exhibits sustained clinical efficacy 4 years after the treatment of intractable essential tremor. Adverse events are generally transient. A large cohort of patients who have undergone magnetic resonance-guided focused ultrasound thalamotomy with longer follow-up is needed to confirm our findings. © 2019 International Parkinson and Movement Disorder Society.

Anatomic Review of the Ventral Capsule/Ventral Striatum and the Nucleus Accumbens to Guide Target Selection for Deep Brain Stimulation for Obsessive-Compulsive Disorder.

BACKGROUND: Disturbances in the reward network of the brain underlie addiction, depression, and obsessive-compulsive disorder. The ventral capsule/ventral striatum and nucleus accumbens (NAc) region is a clinically approved target for deep brain stimulation for obsessive-compulsive disorder. METHODS: We performed a comprehensive literature review to define clinically relevant anatomy and connectivity of the ventral capsule/ventral striatum and NAc region to guide target selection for deep brain stimulation. RESULTS: Architecturally and functionally, the NAc is divided into the core and the shell, with each area having different connections. The shell primarily receives limbic information, and the core typically receives information from the motor system. In general, afferents from the prefrontal cortex, hippocampus, and amygdala are excitatory. The dopaminergic projections to the NAc from the ventral tegmental area modulate the balance of these excitatory inputs. Several important inputs to the NAc converge at the junction of the internal capsule (IC) and the anterior commissure (AC): the ventral amygdalofugal pathways that run parallel to and underneath the AC, the precommissural fornical fibers that run anterior to the AC, axons from the ventral prefrontal cortex and medial orbitofrontal cortex that occupy the most ventral part of the IC and embedding within the NAc and AC, and the superolateral branch of the medial forebrain bundle located parallel to the anterior thalamic radiation in the IC. CONCLUSIONS: The caudal part of the NAc passing through the IC-AC junction may be an effective target for deep brain stimulation to improve behavioral symptoms associated with obsessive-compulsive disorder.

A Case of Coincidental Intrasellar Chordoma and Pituitary Adenoma.

Although chordomas are midline tumors, primarily intrasellar chordomas are extremely rare. In this report, the authors describe the case of a 68-year-old female with partial abducens nerve palsy in the right eye due to the intrasellar cystic tumor. After endonasal trans-sphenoidal surgery, intraoperative and histopathological findings confirmed the co-occurrence of an entirely intrasellar chordoma and pituitary adenoma. To our knowledge, the present case is the third reported case of an intrasellar chordoma with a pituitary adenoma.

Brain Abscesses Associated with Asymptomatic Pulmonary Arteriovenous Fistulas.

Brain abscess commonly occurs secondary to an adjacent infection (mostly in the middle ear or paranasal sinuses) or due to hematogenous spread from a distant infection or trauma. Pulmonary arteriovenous fistulas (AVFs) are abnormal direct communications between the pulmonary artery and vein. We present two cases of brain abscess associated with asymptomatic pulmonary AVF. A 65-year-old woman was admitted with a headache and cognitive impairment that aggravated 10 days prior. An magnetic resonance (MR) imaging revealed a brain abscess with severe edema in the right frontal lobe. We performed a craniotomy and abscess removal. Bacteriological culture proved negative. Her chest computed tomography (CT) showed multiple AVFs. Therapeutic embolization of multiple pulmonary AVFs was performed and antibiotics were administered for 8 weeks. A 45-year-old woman presented with a 7-day history of progressive left hemiparesis. She had no remarkable past medical history or family history. On admission, blood examination showed a white blood cell count of 6290 cells/uL and a high sensitive C-reactive protein of 2.62 mg/L. CT and MR imaging with MR spectroscopy revealed an enhancing lesion involving the right motor and sensory cortex with marked perilesional edema that suggested a brain abscess. A chest CT revealed a pulmonary AVF in the right upper lung. The pulmonary AVF was obliterated with embolization. There needs to consider pulmonary AVF as an etiology of cerebral abscess when routine investigations fail to detect a source.

A Case of Traumatic Unilateral Internuclear Ophthalmoplegia: Clinical Significance of Susceptibility-Weighted Imaging.

A 43-year-old man was admitted for head trauma after falling backward. The patient complained of diplopia. Unilateral internuclear ophthalmoplegia (INO) was diagnosed during the neurologic examination. Initially, no specific finding was shown on T2-weighted, T1-weighted, and fluid attenuated inversion recovery brain magnetic resonance image (MRI) or brain computed tomography (CT). However, susceptibility-weighted imaging (SWI) definitively demonstrated a tiny hemorrhage at the midline of the pontomesencephalic junction. The patient's symptom improved after 12 weeks. We discuss the clinical significance of SWI when traumatic INO due to a tiny hemorrhage is suspected.

The Prevalence of Undiagnosed Presurgical Cognitive Impairment and Its Postsurgical Clinical Impact in Older Patients Undergoing Lumbar Spine Surgery.

OBJECTIVE: Because elderly patients are undergoing more surgeries, the importance of postoperative cognitive impairment (CI) evaluations is rising, especially for spine surgery, which is related to subjective pain. We investigated the prevalence of undiagnosed CI among elderly patients who underwent spine surgery and the impact of CI on postoperative outcomes. METHODS: The preoperative cognitive statuses of 129 patients over 65 who underwent lumbar spine surgery from 2012 to 2014 were determined with the Mini-Mental State Examination, and patients with scores under 24 were diagnosed with CI. The patients were then divided into a CI group (n=49) and non-cognitive impairment (NCI) group (n=80). RESULTS: Among the 129 patients, 49 (38.0%) were diagnosed with CI, and 9 (7.0%) had severe CI. The age of the CI group (72.88±6.20 years) was significantly greater than that of the NCI group (69.96±4.53 years). In contrast, the postoperative visual analog scale scores and performance statuses did not differ significantly. However, postoperative delirium was more frequent and the hospital stay length was longer in the CI group compared with the NCI group (p<0.05). CONCLUSION: A high prevalence of undiagnosed CI was discovered among elderly patients undergoing spine surgery. The existence of CI was associated with higher rates of postoperative delirium and prolonged hospital stays, which affected clinical outcomes. Thus, CI assessments should be included in preoperative evaluations of elderly patients prior to spine surgery.

Acute Contralateral Radiculopathy after Unilateral Transforaminal Lumbar Interbody Fusion.

OBJECTIVE: Cases of contralateral radiculopathy after a transforaminal lumbar interbody fusion with a single cage (unilateral TLIF) had been reported, but the phenomenon has not been explained satisfactorily. The purpose of this study was to determine its incidence, causes, and risk factors. METHODS: We did retrospective study with 546 patients who underwent a unilateral TLIF, and used CT and MRI to study the causes of contralateral radicular symptoms that appeared within a week postoperatively. Clinical and radiological results were compared by dividing the patients into the symptomatic group and asymptomatic group. RESULTS: Contralateral symptoms occurred in 32 (5.9%) of the patients underwent unilateral TLIF. The most common cause of contralateral symptoms was a contralateral foraminal stenosis in 22 (68.8%), screw malposition in 4 (12.5%), newly developed herniated nucleus pulposus in 3 (9.3%), hematoma in 1 (3.1%), and unknown origin in 2 patients (6.3%). 16 (50.0%) of the 32 patients received revision surgery. There was no difference in visual analogue scale and Oswestry disability index between the two groups at discharge. Both preoperative and postoperative contralateral foraminal areas were significantly smaller, and postoperative segmental angle was significantly greater in the symptomatic group comparing to those of the asymptomatic group (p<0.05). CONCLUSION: The incidence rate is not likely to be small (5.9%). If unilateral TLIF is performed for cases when preoperative contralateral foraminal stenosis already exists or when a large restoration of segmental lordosis is required, the probability of developing contralateral radiculopathy is increased and caution from the surgeon is needed.

The Effects of Spinopelvic Parameters and Paraspinal Muscle Degeneration on S1 Screw Loosening.

OBJECTIVE: To investigate risk factors for S1 screw loosening after lumbosacral fusion, including spinopelvic parameters and paraspinal muscles. METHODS: We studied with 156 patients with degenerative lumbar disease who underwent lumbosacral interbody fusion and pedicle screw fixation including the level of L5-S1 between 2005 and 2012. The patients were divided into loosening and non-loosening groups. Screw loosening was defined as a halo sign larger than 1 mm around a screw. We checked cross sectional area of paraspinal muscles, mean signal intensity of the muscles on T2 weight MRI as a degree of fatty degeneration, spinopelvic parameters, bone mineral density, number of fusion level, and the characteristic of S1 screw. RESULTS: Twenty seven patients showed S1 screw loosening, which is 24.4% of total. The mean duration for S1 screw loosening was 7.3±4.1 months after surgery. Statistically significant risk factors were increased age, poor BMD, 3 or more fusion levels (p<0.05). Among spinopelvic parameters, a high pelvic incidence (p<0.01), a greater difference between pelvic incidence and lumbar lordotic angle preoperatively (p<0.01) and postoperatively (p<0.05). Smaller cross-sectional area and high T2 signal intensity in both multifidus and erector spinae muscles were also significant muscular risk factors (p<0.05). Small converging angle (p<0.001) and short intraosseous length (p<0.05) of S1 screw were significant screw related risk factors (p<0.05). CONCLUSION: In addition to well known risk factors, spinopelvic parameters and the degeneration of paraspinal muscles also showed significant effects on the S1 screw loosening.

Role of a Burr Hole and Calvarial Bone Marrow-Derived Stem Cells in the Ischemic Rat Brain: A Possible Mechanism for the Efficacy of Multiple Burr Hole Surgery in Moyamoya Disease.

OBJECTIVE: This study investigates the role of a burr hole and calvarial bone marrow-derived stem cells (BMSCs) in a transient ischemic brain injury model in the rat and postulates a possible mechanism for the efficacy of multiple cranial burr hole (MCBH) surgery in moyamoya disease (MMD). METHODS: Twenty Sprague-Dawley rats (250 g, male) were divided into four groups : normal control group (n=5), burr hole group (n=5), ischemia group (n=5), and ischemia+burr hole group (n=5). Focal ischemia was induced by the transient middle cerebral artery occlusion (MCAO). At one week after the ischemic injury, a 2 mm-sized cranial burr hole with small cortical incision was made on the ipsilateral (left) parietal area. Bromodeoxyuridine (BrdU, 50 mg/kg) was injected intraperitoneally, 2 times a day for 6 days after the burr hole trephination. At one week after the burr hole trephination, brains were harvested. Immunohistochemical stainings for BrdU, CD34, VEGF, and Doublecortin and Nestin were done. RESULTS: In the ischemia+burr hole group, BrdU (+), CD34 (+), and Doublecortin (+) cells were found in the cortical incision site below the burr hole. A number of cells with Nestin (+) or VEGF (+) were found in the cerebral parenchyma around the cortical incision site. In the other groups, BrdU (+), CD34 (+), Doublecortin (+), and Nestin (+) cells were not detected in the corresponding area. These findings suggest that BrdU (+) and CD34 (+) cells are bone marrow-derived stem cells, which may be derived from the calvarial bone marrow through the burr hole. The existence of CD34 (+) and VEGF (+) cells indicates increased angiogenesis, while the existence of Doublecortin (+), Nestin (+) cells indicates increased neurogenesis. CONCLUSION: Based on these findings, the BMSCs through burr holes seem to play an important role for the therapeutic effect of the MCBH surgery in MMD.

CSF flow pathways through the ventricle-cistern interfaces in kaolin-induced hydrocephalus rats-laboratory investigation.

PURPOSE: The goal of this study was to identify direct cerebrospinal fluid (CSF) pathways in the interface between ventricles and cisterns. Such routes are hypothesized to be involved in alternative CSF flows in abnormal circumstances of CSF circulation. METHODS: Chronic obstructive hydrocephalus models were induced in ten Sprague-Dawley rats with kaolin injection into the cisterna magna. Three weeks after the kaolin injection, when thick arachnoid fibrosis obliterated the fourth ventricular outlets, cationized ferritin was stereotactically infused as a tracer into the lateral ventricle in order to observe the pathways from the ventricles to the subarachnoid space. Animals were killed in 48 h and brains were sectioned. CSF flow pathways were traced by the staining of ferritin with ferrocyanide. RESULTS: Eight out of ten rats developed hydrocephalus. The subarachnoid membranes of the convexity and basal cisterns were severely adhered such that most of the ferritin remained in the ventricles whereas basal and convexity cisterns were clear of ferritin. In six out of the eight hydrocephalus rats, ferritin leaked from the third ventricle into the quadrigeminal cistern, and from the lateral ventricle into the ambient cistern. CONCLUSIONS: The interfaces between the third ventricle and the quadrigeminal cistern, and between the lateral ventricle and the ambient cistern appear to be alternative CSF pathways in a pathologic condition such as obstructive hydrocephalus.