Assessment of Navigated Pedicle Screws From Intraoperative Imaging: A Prospective Study of Accuracy and Agreement.

BACKGROUND: Intraoperative (IO) image guidance surgery using 3-dimensional fluoroscopic navigation methods, such as the O-arm system, has improved the accuracy of pedicle screw placement in instrumented spine surgery. IO and postoperative (PO) validation of the implant's correct position from radiological images is a decisive step to ensure patient safety and avoidance of complications related to implant misplacement. In this prospective single-center study, the authors investigated the accuracy and agreement of assessment of pedicle screws from IO O-arm images in comparison to PO computed tomography images. This study aimed to determine whether final evaluation of pedicle screws can safely be conducted from IO images that supersedes the PO computed tomography control. METHODS: A prospective single-center study was carried out at the Spine Unit in the Department of Orthopedics at Umeå University Hospital between 2019 and 2021. All patients enrolled in the study underwent instrumented thoracolumbar spine surgery using navigation. Imaging data were obtained from IO and PO examinations. Four reviewers-2 attending senior spine surgeons, 1 final year resident in orthopedics, and 1 attending neuroradiologist-classified pedicle screws using the Gertzbein and Robbins classification system. Agreement and accuracy of the reviewers were studied to evaluate the assessment of pedicle screws from IO and PO images. RESULTS: A total of 70 patients (422 screws) were included in the study. There was high accuracy among surgeons both on IO and PO images (0.96-0.97, 95% CI [0.94-0.99] and 0.97, 95% CI [0.94-0.99], respectively), and the overall agreement between all raters was 92% to 98% (95% CI [0.90, 1.00]). The discrepancy in assessment between optimal (Group 1) and suboptimal (Group 2) screws between IO and PO images was as low as 1% to 1.7%, which indicates that very few suboptimal screws are missed in the assessment of IO images. CONCLUSIONS: The assessment of navigated pedicle screws using IO images is safe and reliable and may replace the need for further assessment using PO imaging.

Impact of Postoperative Imaging Following Emergency Surgery for Penetrating Ballistic Thoracic Trauma.

INTRODUCTION: Patients undergoing emergent surgical procedures after penetrating trauma can benefit from postoperative imaging studies to identify potential missed injuries or indications to additional surgery. Aim of this study is to describe postoperative imaging findings in patients who underwent emergent operation for thoracic gunshot wounds (GSWs) and the subsequent need for further surgery, diagnostic evaluations or consults. METHODS: Patients who survived to receive imaging evaluation after emergency surgery for penetrating chest trauma in a level I trauma center between 2017 and 2021 were included. Results of postoperative diagnostic evaluation were screened to determine their impact on the subsequent management. RESULTS: Overall, 125 patients admitted with a thoracic GSW underwent an emergent surgical procedure and 29 survived to receive postoperative imaging and were included. Postoperative CT-scan was performed in 26 (89.6%) patients, echocardiography in 8 (27.5%). Other tests included esophagoscopy (1) and bronchoscopy (1). Impact on management of abnormal imaging included a new indication to surgery or additional procedures in 7 cases and need for additional imaging or consults in other 8 cases. Bone fractures and lung injuries were more often diagnosed on postoperative CT-scan. In 3 patients, abnormal echocardiographic findings led to a second cardiac operation. CONCLUSION: Following emergency surgery for penetrating trauma, completion of injury assessment with CT-scan can lead to identification of missed or additional injuries, while other imaging is indicated according to operative findings. In this study, 24.1% had additional surgical pathology identified by postoperative imaging while others had findings requiring additional studies or specialist consult evaluations.

Early Postoperative Computed Tomography Scan Air Distribution Predicts Postoperative CSF Leak in Endoscopic Skull Base Surgery.

BACKGROUND: Cerebrospinal fluid (CSF) leak remains the primary concern of endoscopic skull base surgery (ESBS). Pneumocephalus seen in postoperative images has been linked to CSF leak in some reports; however, few studies have looked at the extent to which it is indicative of CSF leak. In the current study, we aim to examine the size and location of post-ESBS pneumocephalus in the early postoperative period and determine their association with postoperative CSF leak. METHODS: Patients undergoing ESBS in a 5-year period were included. All patients underwent brain computed tomography scan within the first 24 postoperative hours. Computed tomography scans were reviewed by a neurosurgeon and a radiologist and have been classified based on the size and location of pneumocephalus. Patients were followed in the postoperative period for clinical signs of CSF leak and managed accordingly. RESULTS: Out of 120 patients, 86 patients met the inclusion criteria. Thirty-five patients (41%) had no pneumocephalus on day one postoperative imaging, while 51 patients (59%) had pneumocephalus with different sizes and distributions. Eleven of 86 patients developed CSF leak. Of the 11 patients, 5 patients (45%) had grade 4 pneumocephalus (P value = 0.02). Patients with multiple locations of pneumocephalus were more likely to develop CSF leak (P value = 0.01). CONCLUSIONS: In post-ESBS patients, both the volume and location of the pneumocephalus are potentially predictive of CSF leak. In patients with a larger volume of intra-axial air and/or multiple air locations, an impending CSF leak should be anticipated.

Postoperative MRI Visualization of the Cervical Spine Following Cervical Disc Arthroplasty: A Prospective Single-Center Comparison of a Titanium and Cobalt-Chromium Prosthesis.

STUDY DESIGN: Prospective non-randomized single-center cohort study. OBJECTIVES: To analyze the quality of postoperative magnetic resonance imaging of 2 structurally different cervical disc arthroplasty devices at the index and adjacent levels. METHODS: A non-randomized, comparative, prospective, single-center study included 40 patients (23 men and 17 women) aged 32 (26-40) years. Two study groups were utilized: in the first (n = 20), a titanium prosthesis was used; in the second (n = 20), a cobalt-chromium implant was used. Evaluation of MRI studies before and after surgery was performed using sagittal and axial T2 weighted images by 2 specialists who were blinded to the prosthesis that was used. To determine the quality of an MRI image, the classification of Jarvik 2000, the radiological and orthopedic scales for assessing artifacts were used. RESULTS: There was good-to-excellent inter-observer agreement for all of the MR parameters used for the titanium and satisfactory-to-good for the cobalt chromium group. The analysis of the quality of postoperative imaging using the Jarvik 2000 scale showed a statistically significant deterioration in MR images in the cobalt chromium group (P < 0.001), compared to the titanium (P = 0.091). Following a single-level total arthroplasty, the titanium group had better MRI images according to radiological and orthopedic scales (P < 0.001). CONCLUSION: Titanium cervical disc arthroplasty devices result in superior postoperative MR imaging, as compared to cobalt chromium prostheses, as the latter significantly reduces image quality due to the pronounced ferromagnetic effect.

An evaluation of patients with abdominal pain after lateral lumbar interbody fusion.

Context: Abdominal pain after surgery can occur for numerous reasons. Postoperative radiographs may be indicated to evaluate for ileus or other reasons for the pain. Whether outcomes are significantly different based on whether patients get radiographs following lateral lumbar interbody fusion (LLIF) are unclear. Aims: To investigate the postoperative outcomes of patients experiencing abdominal pain after LLIF. Settings and Design: This retrospective cohort study included patients at a tertiary academic medical center and surrounding affiliated hospitals. Materials and Methods: Patients >18 years of age who underwent elective LLIF at a single institution were retrospectively identified. Patients were stratified into two groups depending on whether they received a postoperative abdominal radiograph or computed tomography (CT) scan for postoperative abdominal pain. Statistical Analysis: Patient demographics, surgical characteristics, and surgical outcomes were compared between groups utilizing independent t-tests or Mann-Whitney U-tests for continuous variables or Pearson's Chi-square tests for categorical variables. Results: A total of 153 patients (18 with abdominal scans, 135 without) were included. Patients who received a postoperative abdominal radiograph or CT scan were more likely to undergo exploratory laparotomy (11.1% vs. 0.00%, P = 0.013). Ultimately, patients with abdominal scans had a longer hospital length of stay (6.67 vs. 3.79 days, P = 0.002) and were discharged home less frequently (71.4% vs. 83.7%, P = 0.002). Conclusions: Patients who received abdominal imaging after LLIF were more likely to undergo exploratory laparotomy, experience longer hospital length of stay, and were discharged home less frequently. Intra-abdominal air on postoperative imaging without corresponding physical exam findings consistent with bowel injury is not an appropriate indication for surgical intervention.

The 2023 Stone-Free CT Mandate: Addressing the Two Sides of the Debate.

To the editors of the Journal of Endourology, we write to express our reservations in the recent announcement that starting in 2023 all reporting of stone-free rates be based on CT.

Clinical Utility of Routine Postprocedural Computed Tomography of the Head Following Elective Neuroendovascular Interventions.

BACKGROUND: Little evidence supports acquisition of routine head imaging after uncomplicated elective neurosurgical procedures for patients with unchanged neurological examinations; however, imaging is still performed by some neurointerventionalists. We assessed the clinical utility of routine computed tomography of the head (CTH) following elective neuroendovascular interventions, including aneurysm coiling, aneurysm stent-assisted coiling, aneurysm flow diversion, arteriovenous malformation/fistula embolization, middle meningeal artery embolization for subdural hematoma, extracranial carotid artery stenting, and venous sinus stenting. METHODS: Retrospective chart review identified patients undergoing neuroendovascular intervention from 2011 to 2021 at our institution. Demographic, clinical, and radiographic variables, including presenting signs and symptoms, antiplatelets and/or anticoagulant medications, intraprocedural complications, postprocedural CTH findings, and postprocedural neurological examinations, were recorded. Association of clinical variables with an abnormal postprocedural CTH was assessed with univariate analysis. Patients with ruptured vascular pathology, preoperative embolizations, and missing postprocedural CTH images and/or reports were excluded. RESULTS: Of 509 procedures identified, 354 were eligible for analysis; 4.8% of patients (17/354) had abnormal findings on postprocedural CTH. Nine patients had intraprocedural complications or new postprocedural neurological deficits that would have prompted imaging regardless of institutional practice. None of the remaining 8 (2.3%) patients required additional procedures. New postprocedural neurological deficit was the only significant predictor of abnormal postprocedural CTH (odds ratio = 6.79; 95% confidence interval, 2.01-20.32; P = 0.0009). CONCLUSIONS: In a large cohort of patients undergoing elective neuroendovascular intervention, no patients were identified for whom routine postprocedural CTH alone meaningfully altered their clinical care. Routine CTH is not necessary after uncomplicated elective neuroendovascular interventions performed with careful postprocedural neurological assessment.

Combining gantry-free cone-beam computed tomography with iterative metal artefact reduction for surgical follow-up imaging of the appendicular skeleton.

PURPOSE: Post-surgical evaluation of osteosynthesis material and adjacent tissue can be challenging in both radiography and cross-sectional imaging. This study investigates the performance of a multi-purpose X-ray scanner with cone-beam CT (CBCT) function and iterative metal artefact reduction capabilities in patients after osteoplasty of the appendicular skeleton. METHOD: Eighty individuals who underwent both conventional X-ray imaging and CBCT after osteoplasty of the hand/wrist (48), elbow (14), or ankle/foot (18) with the gantry-free twin robotic system were retrospectively enrolled. Radiological reports from clinical routine for both imaging modalities were retrospectively analyzed and compared with consensus expert reading by two musculoskeletal specialists serving as the standard of reference. Findings of screw dislocation or implant loosening, fragment displacement, and delayed healing were compared between X-ray and CBCT reports using the McNemar test. RESULTS: The median dose-area-product of CBCT and X-ray scans amounted to 27.98 and 0.2 dGy*cm2, respectively. Diagnostic accuracy for screw dislocation was superior in CBCT compared to standard radiograms (98.8 % vs 83.8 %; p = 0.002). Implant loosening (98.8 % vs 86.3 %; p = 0.006), fragment displacement (98.8 % vs 85.0 %; p < 0.001), and delayed healing (97.5 % vs 88.8 %; p = 0.016) were also more reliably detected in CBCT. Employing CBCT, postoperative complications were detected with a sensitivity and specificity of at least 95.8 % and 98.1 %, compared to 33.3 % and 92.86 % in radiography. CONCLUSIONS: With superior accuracy for various osteoplasty-related complications, the CBCT scan mode of a gantry-free twin robotic X-ray system with iterative metal artefact reduction aids post-surgical assessment in the appendicular skeleton.

Clinical Utility of Routine Postoperative Imaging in Spinal Fusion Surgery: A Systematic Review.

OBJECTIVE: Following spinal fusion surgery, routine imaging is often obtained in all patients regardless of clinical presentation. Such routine imaging may include x-ray, computed tomography, or magnetic resonance imaging studies in both the immediate postoperative period and after discharge. The clinical utility of this practice is questionable. Our goal is to assess the existing literature for evidence of impact on clinical care from routine radiographic surveillance following spinal fusion. METHODS: A systematic search of Embase, Scopus, PubMed, Cochrane, and Ovid databases was performed for studies investigating postoperative imaging following spinal fusion surgery. Studies were analyzed for imaging findings and rates of change in management due to imaging. RESULTS: In total, the review identified 9 studies that separated data by unique patient or by unique clinic visits. The 4 studies reporting per-patient data totaled 475 patients with 328 (69%) receiving routine imaging. Among these, 28 (8.5%) patients had abnormal routine findings with no patients having a change to their clinical course. Of the 5 studies that reported clinic visit data, 3119 patient visits were included with 2365 (76%) clinic visits accompanied by imaging. Across these 5 studies, 146 (6.2%) visits noted abnormal imaging with only 12 (0.5%) subsequent management changes. CONCLUSIONS: Our analysis found that routine imaging after spinal fusion surgery had no direct benefit on clinical management. The utility of baseline imaging for long-term comparison and medicolegal concerns were not studied and remain up to the provider's judgment. Further research is necessary to identify optimal imaging criteria following spinal fusion surgery.

MR Imaging of the Postoperative Meniscus.

Meniscal tears are one of the most common knee injuries. Partial meniscectomy and meniscal repair are the most common treatment options in the setting of an unstable meniscal tear. Standard MR diagnostic criteria of a meniscal tear may be normal findings postoperatively. The diagnosis of a recurrent or residual meniscal tear after prior meniscal surgery is primarily based on the visualization of surfacing high meniscal T2-weighted signal. After meniscectomy of greater than 25%, or meniscal repair, MR arthrography may be of benefit in the accurate evaluation of a possible residual or recurrent meniscal tear.

Mapping Motor Pathways in Parkinson's Disease Patients with Subthalamic Deep Brain Stimulator: A Diffusion MRI Tractography Study.

INTRODUCTION: This study assessed the safety of postoperative diffusion tensor imaging (DTI) with on-state deep brain stimulation (DBS) and the feasibility of reconstruction of the white matter tracts in the vicinity of the stimulation site of the subthalamic nucleus (STN). The association between the impact of DBS on the nigrostriatal pathway (NSP) and the treatment effect on motor symptoms in Parkinson's disease (PD) was then evaluated. METHODS: Thirty-one PD patients implanted with STN-DBS (mean age: 66 years; 25 male) were scanned on a 1.5-T magnetic resonance imaging (MRI) scanner using the DTI sequence with DBS on. Twenty-three of them were scanned a second time with DBS off. The NSP, dentato-rubro-thalamic tract (DRTT), and hyperdirect pathway (HDP) were generated using both deterministic and probabilistic tractography methods. The DBS-on-state and off-state tractography results were validated and compared. Afterward, the relationships between the characteristics of the reconstructed white matter tracts and the clinical assessment of PD symptoms and the DBS effect were further examined. RESULTS: No adverse events related to DTI were identified in either the DBS-on-state or off-state. Overall, the NSP was best reconstructed, followed by the DRTT and HDP, using the probabilistic tractography method. The connection probability of the left NSP was significantly lower than that of the right side (p < 0.05), and a negative correlation (r = -0.39, p = 0.042) was identified between the preoperative symptom severity in the medication-on state and the connection probability of the left NSP in the DBS-on-state images. Furthermore, the distance from the estimated left-side volume of tissue activated (VTA) by STN-DBS to the ipsilateral NSP was significantly shorter in the DBS-responsive group compared to the DBS-non-responsive group (p = 0.046). CONCLUSIONS: DTI scanning is safe and delineation of white matter pathway is feasible for PD patients implanted with the DBS device. Postoperative DTI is a useful technique to strengthen our current understanding of the therapeutic effect of DBS for PD and has the potential to refine target selection strategies for brain stimulation.

For some more seriously affected Parkinson's disease (PD) patients, drugs are no longer effective in treating their symptoms. An alternate treatment is to use deep brain stimulation (DBS), a commonly used neurosurgical therapy for PD patients. For those DBS treatments targeting the subthalamic nucleus (STN), the electrical stimulation used may impact nearby white matter tracts and alter the effectiveness of the DBS treatment. The nigrostriatal pathway (NSP), dentato-rubro-thalamic tract, and hyperdirect pathway are three white matter tracts near the STN. They are all relevant to motor symptoms in PD. This study examined whether imaging these tracts using magnetic resonance imaging (MRI) is safe and feasible in the presence of DBS leads. The relationships between the fiber-tracking characteristics and distance to the DBS leads were then evaluated. For this purpose, 31 PD patients with stimulation-on were scanned on a 1.5 T MRI scanner using a diffusion tensor imaging sequence. A total of 23 subjects underwent another scan using the same sequence with stimulation-off. No adverse events related to diffusion tensor imaging were found. Among the white matter tracts near the STN, the NSP was best delineated, followed by the dentato-rubro-thalamic tract and the hyperdirect pathway. The connection probability of the left NSP was significantly lower than that of the right side as were the subject's motor symptoms. The closer the distance between the NSP and the stimulation location, the better the DBS outcome. These findings indicate that imaging white matter tracts with DBS on is safe and useful in mapping DBS outcomes.

Visualization of Different Types of Cochlear Implants in Postoperative Cone-Beam CT Imaging.

RATIONALE AND OBJECTIVES: To evaluate cone-beam computed-tomography (CBCT) images of the temporal bone for radiological delineation, metal artifacts, and accuracy for localization of six different electrode arrays after cochlear device implantation. MATERIALS AND METHODS: This retrospective study included 116 patients who underwent CBCT (120kV, 7.1mA) within 24 hours after cochlear device implantation. Exclusion criteria were anatomical abnormalities, and electrode misinsertion. Six different CI electrodes were implanted: Advanced Bionics HiFocus Mid-Scala, Cochlear Contour Advance, Cochlear Slim-Straight, Cochlear Slim-Modiolar, MED-EL Flex 24 and MED-EL Flex 28. Two radiologists rated independently presence of metal artifacts, overall image quality, as well as dedicated visualization of the osseous spiral lamina, inner and outer cochlear wall, single electrode contacts, and electrode position using 5-point-Likert scales. Inter-rater agreement was calculated by using Cohen's kappa and intraclass correlation. RESULTS: Of 116 patients, 94 (81.0%; 56.1 ± 16.9 years; age range, 13-86 years; 49 [52.1%] females) were included in the study. Overall image quality was rated good for all electrode models without significant differences (p = 0.061). Depiction of electrode contacts was rated significantly better for Advanced Bionics HiFocus Mid-Scala, Cochlear Slim-Straight, and MED-EL Flex 24 and 28 compared to Cochlear Contour Advance and Slim-Modiolar (p < 0.001). Depiction of the osseous spiral lamina (p = 0.20), inner (p = 0.42) and outer cochlear wall (p = 0.35), metal artifacts (p = 0.18), and electrode position (p = 0.31) did not show significant differences between electrode models. Inter-rater agreement varied from substantial to almost perfect (0.70-0.93). CONCLUSION: CBCT provides excellent visualization of all evaluated CI electrode types, in particular electrode arrays with greater spacing between contacts and contact size allow improved radiologic evaluation.

Fusion of Preoperative and Postoperative Imaging May Predict the Diagnostic Yield of Stereotactic Needle Brain Biopsies.

BACKGROUND: Stereotactic needle brain biopsy is a commonly used neurosurgical procedure. However, up to 15% of biopsies result in undiagnostic pathology reports. Repeat biopsy or continued management without a diagnosis are often considered after undiagnostic biopsies. There have been no reports about the role of postoperative imaging in predicting the diagnostic yield of stereotactic biopsies. METHODS: We retrospectively assessed all stereotactic biopsies performed over an 11-year period. We performed fusion of immediate postoperative computed tomography (CT) with preoperative MRI, to document whether the air bubble in the postoperative CT was located within the targeted lesion. We then evaluated the association of this fusion-based accuracy assessment with the diagnostic yield of the biopsy. RESULTS: Fewer than 5% of biopsies did not have an air bubble on postoperative CT. A total of 226 biopsies were performed for 219 patients. In our sample, 213 of 226 biopsies were accurate (94.2% accuracy rate), and 203 of 226 biopsies gave a definitive diagnosis (89.8% diagnostic rate). In those cases where the fusion was accurate, the diagnostic rate was 93.9%. When the fusion was inaccurate, the diagnostic rate was only 23.1% (odds ratio 51.5, 95% confidence interval 12.6-210.44, P < 0.001). Of all patient, imaging, surgical, and admission parameters, the only parameter that correlated with diagnostic outcome of the biopsy was the fusion construct accuracy. CONCLUSIONS: Fusion of immediate postoperative CT with preoperative imaging is predictive of the diagnostic rate. In cases where the pathology report following a biopsy is not diagnostic, this fusion may be useful in making decisions regarding repeat biopsy or considering other diagnostic options.

Updates in postoperative imaging modalities following musculoskeletal surgery.

Postoperative imaging following orthopaedic surgeries is essential in assessing complications post-surgery and also helps plan further treatment. Combining a high degree of clinical insight with appropriate imaging can guide the treating clinician to the correct diagnosis. Imaging is quite challenging because of surgery-related soft tissue changes, especially in the early postoperative period and the presence of metal implants resulting in image scatter and metal artifacts. Newer modalities and advances in imaging have helped overcome shortcomings and assess better, especially in procedures that involve implants. Collaborative decision-making involving radiologists and clinicians has shown to be beneficial and is the way forward. This narrative review discusses the utility of imaging in evaluating postoperative complications following musculoskeletal surgeries with specific relation to trauma, arthroplasty, and tumour by discussing commonly encountered clinical scenarios.

Postoperative lumbar spine MRI: How well does a radiology report that raises suspicion for infection correlate with true clinical infection?

INTRODUCTION: Interpretation of a lumbar spine MRI in the immediate postoperative period is challenging, as postoperative tissue enhancement and fluid collections may be mistaken for infection. Radiology reports may use ambiguous language, creating a clinical problem for a surgeon in determining whether a patient needs treatment with antibiotics or revision surgery. Moreover, retrospective criticism of management in instances of a true infection may lead to medicolegal ramifications. METHODS: A retrospective review of patients undergoing posterior-approach lumbar decompressive surgery with or without fusion over a 30-month period identified those undergoing postoperative MRI within 10 weeks of surgery. Patients initially operated upon for infection were excluded. The MRI reports were analyzed for language describing findings suspicious for infection and those of these with true infections were identified. RESULTS: Of 487 patients undergoing posterior lumbar spine decompression surgery, 68 (14%) had postoperative MRI within 10 weeks. Of these, the radiology reports raised suspicion for infection in 20 (29%), of which 2 (10%) patients had a true infection. Two patients underwent reoperation for new motor deficit from seroma/hematoma. Of 63 patients who had MRI to evaluate complaints of back and/or leg pain without new motor deficits, the MRI significantly altered management in 3 patients (4.8%). CONCLUSION: Radiology reports of postoperative lumbar spine MRIs frequently use language that raises suspicion for infection; but it is uncommon, however, that these patients harbor true infections. A radiology report describing possible infectious findings may not be considered significant without corroboration with other laboratory and clinical data.

Correlation between FDG-PET uptake and survival in patients with primary brain tumors.

This study evaluates F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) semi-quantitative analysis as biomarker of tumor aggressiveness and predictor of survival in patients with primary brain tumors. Semi-quantitative analyses (SUVmax, SUVmean) were derived from FDG PET images in 78 patients with suspected recurrence of primary brain tumors based on MRI. SUVmax and the ratio of lesion SUVmax to the SUVmean of contralateral white matter (SUVmax/WM) were measured. A one-way Analysis of Variance (ANOVA), Kaplan-Meier analyses and the log rank test for evaluating statistical significance were utilized. There was statistical significance for time between FDG-PET and patient death. There was a significant difference with respect to FDG-PET time to death between patients with glioblastoma and patients with anaplastic oligodendroglioma, oligodendroglioma, and other histological subtypes. There is significant correlation with SUVmax/WM and patient survival following FDG-PET when a cut-point ratio of 1.90 is used. A 1.90 cut-point ratio of SUVmax/WM was associated with a difference in survival. GBM was associated with a significant difference in terms of reduced survival following FDG PET compared to most other histological sub-types. These results may inform current treatment and counseling strategies for patients with primary brain tumors.

Delayed hemorrhage after pediatric stereo-electroencephalography: delayed occurrence or delayed diagnosis?

BACKGROUND: Stereo-electroencephalography (SEEG) is a well-known invasive diagnostic method for drug-resistant epilepsy (DRE). Its rate of complications is relatively low, being the intracranial hemorrhage (ICH) the most relevant. Most centers perform immediate imaging studies after SEEG to rule out complications. However, delayed intracranial hemorrhages (DIH) can occur despite normal imaging studies in the immediate postoperative period. METHODS: We performed a retrospective review of DRE pediatric patients operated on SEEG between April 2016 and December 2020 in our institution. After implantation, an immediate postoperative CT was performed to check electrode placement and rule out acute complications. An additional MRI was performed 24 h after surgery. We collected all postoperative hemorrhages and considered them as major or minor according to Wellmer´s classification. RESULTS: Overall, 25 DRE patients were operated on SEEG with 316 electrodes implanted. Three ICHs were diagnosed on postoperative imaging. Two of them were asymptomatic requiring no treatment, while the other needed surgical evacuation after clinical worsening. The total risk of hemorrhage per procedure was 12%, but just one third of them were clinically relevant. Two hemorrhages were not visible on immediate postoperative CT, being incidentally diagnosed in the 24 h MRI. We recorded them as DIH and are reported in detail. CONCLUSION: Few reports of DIH after SEEG exist in the literature. It remains unclear whether these cases are late occurring hemorrhages or immediate postoperative hemorrhages undiagnosed on initial imaging. According to our findings, we recommend to perform additional late postoperative imaging to diagnose these cases and manage them accurately.

Comparison of MRI Visualization Following Minimally Invasive and Open TLIF: A Retrospective Single-Center Study.

Analysis of magnetic resonance image (MRI) quality after open (Op)-transforaminal interbody fusion (TLIF) and minimally invasive (MI)-TLIF with the implantation of structurally different systems has not previously been performed. The objective of this study was to conduct a comparative analysis of the postoperative MRI following MI and Op one-segment TLIF. MATERIAL AND METHODS: The nonrandomized retrospective single-center study included 80 patients (46 men and 24 women) aged 48 + 14.2 years. In group I (n = 20) Op-TLIF with open transpedicular screw fixation (TSF) was performed, in II group (n = 60), the MI-TLIF technique was used: IIa (n = 20)-rigid interspinous stabilizer; IIb (n = 20)-unilateral TSF and contralateral facet fixation; IIc (n = 20)-bilateral TSF. RESULTS: Comparison of the quality of postoperative imaging in IIa and IIb subgroups showed fewer MRI artifacts and a significantly greater MR deterioration after Op and MI TSF. Comparison of the multifidus muscle area showed less atrophy after MI-TLIF and significantly greater atrophy after Op-TLIF. CONCLUSION: MI-TLIF and Op-TLIF with TSF have comparable postoperative MR artifacts at the operative level, with a greater degree of muscle atrophy using the Op-TLIF. Rigid interspinous implant and unilateral TSF with contralateral facet fixation have less artifacts and changes in the multifidus muscle area.

Recommendations for Postoperative Surveillance of Pediatric Benign Ovarian Neoplasms.

STUDY OBJECTIVE: To assess postoperative management of pediatric patients with benign ovarian neoplasms, to develop recommendations for postoperative care. DESIGN: A retrospective cohort study. SETTING: Eight pediatric hospitals in the midwestern United States. PARTICIPANTS: Patients up to 21 years of age who underwent surgery for a benign ovarian neoplasm between January 2010 and December 2016 were included. INTERVENTIONS: No prospective interventions were evaluated. MAIN OUTCOME MEASURES: Main outcome measures included postoperative imaging findings, recurrence rates, reoperation rates, and the timing of the aforementioned results. RESULTS: A total of 427 patients met inclusion criteria. After the index surgery, 155 patients (36%) underwent a routine imaging study. Among those with routine imaging, abnormalities were noted in 48 patients (31%); 7 went on to have reoperation (5%), and no malignant pathologies or torsion were identified. Excluding the 7 patients who went on to have a reoperation as a result of routine imaging, 113 patients developed symptoms postoperatively and underwent imaging as a result (27%, 113/420). Abnormalities were noted in 44 (10%); 15 of these patients underwent reoperation (4%), among them 2 with malignancies and 3 with torsion. Of these 44 patients, 23 had initially undergone routine imaging and subsequently went on to have symptomatic imaging, with 17% (4/23) undergoing reoperation. CONCLUSIONS: Routine imaging did not identify malignancy; most lesions identified on routine imaging were incidental findings. Although the study was not powered to appreciate a statistically significant difference, patients with malignancy or torsion were identified in the symptomatic group. This suggests no benefit from routine imaging, and supports symptomatic imaging postoperatively to minimize costs and patient/family burden.

Aortic injury in spine surgery What a spine surgeon needs to know.

Aortic injury is a rare, yet underreported and underestimated complication of spine surgery. Anatomical relation between the aorta and the spine changes under physiological (positional) as well as pathological (deformity) conditions, which puts the aorta at risk of injury during spine surgery. Clinical presentation of aortic injury ranges from asymptomatic perforation of the aorta to acute fatal bleeding. Although several diagnostic methods have been reported, CT-angiography remains an important diagnostic study. Several advancements in the open and the endovascular surgical management have been reported to be successfully used in the management of aortic injury following spine surgery. Management approach of malpositioned screws abutting the aorta is still controversial. Anatomical knowledge and understanding of the previously reported mechanisms of aortic injury are important to be integrated in the preoperative planning process. If the complication occurs, time-to- recognition and to-appropriate-management are important factors for predicting mortality. If unrecognized and untreated in the acutely injured patients, mortality can approach 100%.