Rapid Spontaneous Resolution of Contralateral Lentiform Acute Subdural Hematoma After Burr Hole Trephination for Chronic Subdural Hematoma.

Although rare, acute subdural hematoma (ASDH) may occur after burr hole trephination (BHT) for chronic subdural hematoma (CSDH). It usually occurs in the hemisphere ipsilateral to the burr hole site and rarely in the hemisphere contralateral to the burr hole site. On computed tomography (CT), SDH is usually crescent-shaped and occasionally lentiform or biconvex, which can be misdiagnosed as epidural hematoma (EDH). In rare cases, ASDH may resolve spontaneously and rapidly. Here, we report a case of rapid spontaneous resolution of contralateral lentiform ASDH after BHT for CSDH in a patient with brain atrophy. A 55-year-old man developed left CSDH 2 months after traumatic brain injury. Left BHT was performed, and a lentiform hematoma, presumed to be EDH, was found in the right frontal region on the CT scan acquired immediately after BHT. On the CT scan acquired 12 hours later, the lentiform hematoma disappeared and spread along the hemisphere. It was presumed to be ASDH. To prevent contralateral ASDH after BHT, slow decompression and minimal gentle or no irrigation should be performed during BHT, particularly in patients with brain atrophy.

Stent-assisted Coiling vs. Flow Diverter for Treating Blood Blister-like Aneurysms : A Proportion Meta-analysis.

PURPOSE: Blood blister-like aneurysms (BBAs) are rare vascular lesions and a therapeutic challenge. Although endovascular treatment of BBA is a promising approach, the optimal treatment remains controversial. The purpose of this study was to compare the safety and efficacy of stent-assisted coiling (SAC) and flow diverter (FD) in the management of BBAs. METHODS: A proportion meta-analysis including a published series of BBAs treated with endovascular approaches from 2009 to 2020 including SAC and FD was performed by searching English language studies via MEDLINE and EMBASE. RESULTS: The 32 studies included 16 based on SAC and 16 involving FD. The long-term complete occlusion rate was higher in FD (89.26%, 95% confidence interval, CI 82.93-94.26%, I2 = 14.42%) than in SAC (70.26%, 95% CI 56.79-82.13%, I2 = 70.60%). The rate of aneurysm recanalization was lower in FD (4.54%, 95% CI 1.72-8.16%, I2 = 0%) than in SAC (25.38%, 95% CI 14.44-38.19%, I2 = 67.31%). Rates of mortality, favorable functional outcome, procedural complications, and rebleeding showed no differences between the two procedures. CONCLUSION: In a proportion meta-analysis comparing FD with SAC, the FD was associated with more favorable angiographic outcomes but similar complications and clinical outcomes.

Does the Size of Unilateral Decompressive Craniectomy Impact Clinical Outcomes in Patients with Intracranial Mass Effect after Severe Traumatic Brain Injury?

OBJECTIVE: Decompressive craniectomy (DC) is one of the treatment modalities in severe traumatic brain injury (TBI), however, there was a lack of evidence for optimal craniectomy size. The authors aimed to investigate optimal DC size and analyze clinical outcome according to craniectomy size. METHODS: We retrospectively reviewed the medical data of 87 patients with a space occupying lesion following TBI who underwent unilateral DC. Craniectomy size was measured by anterior-posterior (AP) diameter and surface estimate (SE). Mortality, clinical outcome, and complications were collected and analyzed according to craniectomy size. RESULTS: Nineteen patients (21.8%) died and 35 patients (40.2%) had a favorable outcome at last follow-up (a mean duration, 30.3±39.4 months; range, 0.2-132.6 months). Receiver operating curve analyses identified AP diameter more than 12.5 cm (area under the curve [AUC]=0.740; p=0.002) and SE more than 98.0 cm2 (AUC=0.752; p=0.001) as cut-off values for survival, and AP diameter more than 13.4 cm (AUC=0.650; p=0.018) and SE more than 107.3 cm2 (AUC=0.685; p=0.003) for favorable outcome. Large craniectomy resulted in a significantly lower mortality rate and a higher rate of favorable outcome than small craniectomy (p=0.005 and p=0.014, respectively). However, procedure related bleeding occurred more frequently in the large craniectomy group (p=0.044). CONCLUSION: Unilateral DC size is associated with clinical outcome of patients with a space occupying lesion following severe TBI. Large craniectomy is needed for survival and favorable outcome.

Longitudinal change of cervical artificial disc motion following replacement.

We reviewed charts and radiologic studies of 30 patients operated upon by ADR with Mobi-C® in single level since 2006. All patients had healthy cervical facet joints (less than or equal to grade 1 according to grading systems for cervical facet joint degeneration) preoperatively. We assessed clinical outcomes with NDI and VAS on neck and arm over follow-up and also measured ROM at implanted segment on dynamic radiographs during follow-up. The mean follow-up period was 42.4 ± 15.9 months. We then assessed the linearity of changes in ROM at implanted segment through linear mixed model. All patients showed significantly improved clinical outcomes. ROMs at implanted segment were maintained at slightly increased levels until 24 months postoperatively (P = 0.529). However, after 24 months, ROMs at implanted segment decreased significantly until last follow-up (P = 0.001). In addition, the decreasing pattern after 24 months showed a regular regression (P = 0.001). This decline was correlated with decline of extension angle at implanted segment. Based on this regular regression, we estimated that ROMs at implanted segments would be less than 2 degrees at 10.24 years postoperatively. Even though implanted segment maintains its motion for some length of time, we could assume that an artificial disc would have limited life expectancy correlated with the decline of extension angle.

Lateral Lumbar Interbody Fusion and in Situ Screw Fixation for Rostral Adjacent Segment Stenosis of the Lumbar Spine.

OBJECTIVE: The purpose of this study is to describe the detailed surgical technique and short-term clinical and radiological outcomes of lateral lumbar interbody fusion (LLIF) and in situ lateral screw fixation using a conventional minimally invasive screw fixation system (MISF) for revision surgery to treat rostral lumbar adjacent segment disease. METHODS: The medical and radiological records were retrospectively reviewed. The surgery was indicated in 10 consecutive patients with rostral adjacent segment stenosis and instability. After the insertion of the interbody cage, lateral screws were inserted into the cranial and caudal vertebra using the MISF through the same LLIF trajectory. The radiological and clinical outcomes were assessed preoperatively and at 1, 3, 6, and 12 months postoperatively. RESULTS: The median follow-up period was 13 months (range, 3-48 months). Transient sensory changes in the left anterior thigh occurred in 3 patients, and 1 patient experienced subjective weakness; however, these symptoms normalized within 1 week. Back and leg pain were significantly improved (p<0.05). In the radiological analysis, both the segmental angle at the operated segment and anterior disc height were significantly increased. At 6 months postoperatively, solid bony fusion was confirmed in 7 patients. Subsidence and mechanical failure did not occur in any patients. CONCLUSION: This study demonstrates that LLIF and in situ lateral screw fixation may be an alternative surgical option for rostral lumbar adjacent segment disease.

Quantity of Disc Removal and Radiological Outcomes of Percutaneous Endoscopic Lumbar Discectomy.

BACKGROUND: Herniated intervertebral disc disease (HIVD) is a common cause of lower back and leg pain. Percutaneous endoscopic lumbar discectomy (PELD) is indicated when non-surgical treatments such as medication and interventions are intractable. Ruptured discs and loose fragments inside discs are removed during PELD. Nerve root decompression is usually assessed by visualizing the free movement of the traversing nerve root or epidural fat, the free passage of a probe into the epidural space, the depression of the annulus, and the removal of the expected ruptured discs and loose fragments based on preoperative magnetic resonance images (MRI). However, these criteria are subjective, and the quantity of the disc removal necessary for successful outcomes after PELD has not been investigated. OBJECTIVES: The present study investigates the amount of discectomy of PELD and its clinical and radiological outcomes. STUDY DESIGN: A retrospective case study (IRB Number H-1611-015-803). SETTING: University Medical Center, Seoul, Korea. METHODS: PELD was performed in 109 consecutive patients (M:F = 53:56; mean age, 37.4 years) using the transforaminal or interlaminar route. Ruptured disc fragments were first removed in all patients, and the graspable loose fragments under the disc were removed. After surgery, all removed disc fragments were placed into disposable syringes and manually compressed to measure their volume. The volume of herniated disc outside the disc boundary was calculated in MRI. The measured and calculated disc volumes were retrospectively compared. Clinical success was defined as an improvement in both the Oswestry Disability Index (ODI) and leg pain, as well as no recurrent symptoms. Radiological success was defined as the disappearance of herniated disc material outside the disc boundary based on postoperative MRI taken within one day after surgery. The follow-up period was 7.2 ± 5.2 months. RESULTS: Successful clinical outcomes were obtained in 96/109 (88.1%) patients in a median time of 3 months. Re-operation was performed in 3 patients due to recurrent discs in 2 patients and a residual disc in one patient. Predictors of clinical success were not identified, and the quantity of the removed disc was not associated with the clinical outcome. Radiological success was achieved in 93/109 (85.3%) patients. Of 13 patients with radiological failure, 2 patients showed clinical failure. A logistic regression analysis showed that the relative volume of the removed disc (%) compared with the volume of preoperative herniated disc based on the MRI was the only significant predictor (P < 0.001; OR = 0.96). When 100% of the calculated disc amount was removed during the operation, the probability of residual disc was 30%. When 131% of the calculated disc amount was removed, the probability of residual disc was 10%. LIMITATIONS: This study employed a retrospective design, and its inherent selection bias and limited statistical power should be considered. CONCLUSIONS: The amount of disc removal during PELD was not a significant predictor of clinical success after the primary ruptured fragments were removed. The relative volume of the removed disc based on the preoperative MRI might predict the postoperative MRI. KEY WORDS: Disc, lumbar vertebra, discectomy, surgery, endoscopy, volume.

How to address cerebrospinal fluid leakage following ossification of the posterior longitudinal ligament surgery.

BACKGROUND: Primary dural repair in ossification of posterior longitudinal ligament (OPLL) surgery via anterior is challenging because of limited space. Based on several years of our experiences, we present our concept for addressing cerebrospinal fluid (CSF) leakage following dural tear during anterior OPLL surgery. METHODS: We reviewed the medical records of 65 patients who underwent anterior OPLL surgery from 2003 to 2014. We included 7 patients whose operation records described dural tear followed by CSF leakage. Primary dural repair could not be performed in 6 patients because of ragged tear and limited space. We managed them with our own strategy: simple cover with an artificial dura, collagen sponge and/or fibrin glue on defect site; anatomical layer-by-layer repair without either subfascial or CSF drain, and early ambulation. RESULTS: Of 7 patients, wound problems developed in 2 patients. Wound aspiration and antibiotic treatment was done without wound compression in one patient, and simple irrigation followed by anatomical layer-by-layer re-closure was done in the other patient without either bed rest or lumbar drainage. Pseudomeningoceles were detected in 4 patients, including 2 patients who had wound problems. However, all pseudomeningoceles were absorbed spontaneously or stabilized on follow-up images without interventions such as bed rest, lumbar drain or wound compression. CONCLUSIONS: Without interference of pressure equilibrium between intradural and extradural space, the defect site would heal and close. After that, the isolated pseudomeningocele would be spontaneously absorbed after certain period of time.

Comparison of Cervical Sagittal Alignment and Kinematics after Posterior Full-endoscopic Cervical Foraminotomy and Discectomy According to Preoperative Cervical Alignment.

BACKGROUND: The progression of cervical kyphosis due to injury to the facet joints and musculature is a major concern for posterior foraminotomy especially for patients with cervical lordosis of less than 10°. However, cervical hypo-lordosis (cervical lordosis < 10°) may be improved with the alleviation of pain and muscle spasms, which corresponds with the disappearance of a positive Spurling's test. When surgery is necessary, the spontaneous recovery of cervical curvature may be minimally offset using minimally invasive surgical techniques, such as posterior percutaneous endoscopic cervical foraminotomy (P-PECF). OBJECTIVES: The primary objective was to compare the changes in cervical kinematics between patients with cervical lordosis (≥ 10°, group I) and hypo-lordosis (< 10°, group II) after P-PECF. STUDY DESIGN: This study was a retrospective nested case-control study with the IRB No. H-1210-078-434. SETTING: University Medical Center, Seoul, Korea. METHODS: P-PECFs were performed for patients with a radiculopathy due to single-level unilateral cervical foraminal soft-disc herniations or foraminal stenosis with minimal degeneration of the disc/facet joints and a positive Spurling's test. A retrospective nested case-control study was performed for 23 patients with cervical lordosis of ≥ 10° (group I; M:F = 15:8; age, 52.3 ± 9.8 years) and 23 patients with cervical lordosis of < 10°(group II; M:F = 15:8; age, 46.3 ± 12.7 years). P-PECFs were performed using the methods previously reported, and all patients were discharged the next day without limitations on neck motion. The patients were followed at one, 3, 6, and 12 months postoperatively and yearly thereafter. The follow-up period was 25.8 ± 19.6 months. Clinical outcomes were assessed using the visual analogue pain score of arms. The cervical angles (C2-7, tangential method) were measured on neutral (CA), flexion (CAF), and extension (CAE) lateral radiographs, and range of motion (C-ROM) was calculated by conducting a radiological analysis. A linear mixed model was used to assess the linearity of the changes in cervical curvatures during the postoperative 12 months between the groups. RESULTS: Significant reductions in arm pain and negative results on Spurling's test were initially achieved in 21/23 patients in group I and in 23/23 patients in group II with means of 1.7 ± 0.31 months and 1.09 ± 0.09 months, respectively. Using the mixed effect models, the interactions between group and time were significant for the CA (P = 0.004), CAE (P < 0.001), and C-ROM (P < 0.001) but not the CAF (P = 0.392). The CA (adjusted-P < 0.001), CAE (adjusted-P < 0.001), and C-ROM (adjusted-P = 0.046) exhibited significant between-group differences at the pre-operation. However, during the follow-up, these parameters were significantly changed in group II, especially during the postoperative 3 months. The CA, CAE, and C-ROM changed by -11.73°, -19.87°, and 20.32°, respectively. Postoperatively, 17/23 patients in group II and 22/23 patients in group I exhibited cervical lordosis of ≥ 10°. LIMITATIONS: This study was retrospective in design, and the inherent selection bias and limited statistical power should be considered. CONCLUSIONS: Cervical hypo-lordosis less than 10° may not be a contra-indication for P-PECF when the change of cervical curvature is not a structural change. A larger study is necessary to identify prognostic factors. Key words: Alignment, cervical vertebrae, disc, percutaneous, endoscopes, biomechanical phenomena, surgery, lordosis, kyphosis.

Sagittal imbalance in patients with lumbar spinal stenosis and outcomes after simple decompression surgery.

BACKGROUND CONTEXT: Lumbar spinal stenosis (LSS) is the most common lumbar degenerative disease, and sagittal imbalance is uncommon. Forward-bending posture, which is primarily caused by buckling of the ligamentum flavum, may be improved via simple decompression surgery. PURPOSE: The objectives of this study were to identify the risk factors for sagittal imbalance and to describe the outcomes of simple decompression surgery. STUDY DESIGN: This is a retrospective nested case-control study PATIENT SAMPLE: This was a retrospective study that included 83 consecutive patients (M:F=46:37; mean age, 68.5±7.7 years) who underwent decompression surgery and a minimum of 12 months of follow-up. OUTCOME MEASURES: The primary end point was normalization of sagittal imbalance after decompression surgery. METHODS: Sagittal imbalance was defined as a C7 sagittal vertical axis (SVA) ≥40 mm on a 36-inch-long lateral whole spine radiograph. Logistic regression analysis was used to identify the risk factors for sagittal imbalance. Bilateral decompression was performed via a unilateral approach with a tubular retractor. The SVA was measured on serial radiographs performed 1, 3, 6, and 12 months postoperatively. The prognostic factors for sagittal balance recovery were determined based on various clinical and radiological parameters. RESULTS: Sagittal imbalance was observed in 54% (45/83) of patients, and its risk factors were old age and a large mismatch between pelvic incidence and lumbar lordosis. The 1-year normalization rate was 73% after decompression surgery, and the median time to normalization was 1 to 3 months. Patients who did not experience SVA normalization exhibited low thoracic kyphosis (hazard ratio [HR], 1.04; 95% confidence interval [CI], 1.02-1.10) (p<.01) and spondylolisthesis (HR, 0.33; 95% CI, 0.17-0.61) before surgery. CONCLUSIONS: Sagittal imbalance was observed in more than 50% of LSS patients, but this imbalance was correctable via simple decompression surgery in 70% of patients.

Nocardia brain abscess in a liver transplant recipient.

Nocardia brain abscess is rare. We report on a unique case of N. farcinica brain abscess in a liver transplant recipient, following Aspergillus fumigatus pneumonia. A 43-year-old liver transplant recipient presented with altered mentality at 2 months after A. fumigates pneumonia. He was successfully treated with surgical removal and antibiotic therapy with trimethoprim-sulfamethoxazole and ceftriaxone.

Vein of galen aneurysmal malformation : endovascular management of 6 cases in a single institute.

OBJECTIVE: The aim of this study was to analyze the treatment outcome of patients with vein of Galen aneurysmal malformations (VGM). METHODS: Clinical and angiographic data of six consecutive patients with VGM were retrospectively reviewed. VGMs were angiographically classified by Yasargil's method. Treatment outcomes were evaluated. RESULTS: Mean age at initial treatment was 4.4±5.7 months. Angiographic types of VGMs were type II in two patients and type III in four. Three patients had cardiac symptoms and the others were asymptomatic. Two patients were treated with transvenous embolization, three with transarterial embolization, and one was managed conservatively. Two patients died due to venous hypertension few days after transvenous approach. Of three patients who were transarterially embolized, one was completely occluded with Onyx and two were incompletely occluded. During the follow-up period (range, one to six years) two of three patients treated with transarterial approach were asymptomatic and the other showed mild symptoms. One patient who was managed conservatively showed normal performance. CONCLUSION: Transarterial embolization of VGMs may be better than transvenous approach in terms of the treatment outcome and complication. Further studies are needed because of the rarity of the disease and rapid advancement of endovascular techniques.