The Accuracy of Patient-Specific Spinal Drill Guides Is Non-Inferior to Computer-Assisted Surgery: The Results of a Split-Spine Randomized Controlled Trial.

In recent years, patient-specific spinal drill guides (3DPGs) have gained widespread popularity. Several studies have shown that the accuracy of screw insertion with these guides is superior to that obtained using the freehand insertion technique, but there are no studies that make a comparison with computer-assisted surgery (CAS). The aim of this study was to determine whether the accuracy of insertion of spinal screws using 3DPGs is non-inferior to insertion via CAS. A randomized controlled split-spine study was performed in which 3DPG and CAS were randomly assigned to the left or right sides of the spines of patients undergoing fixation surgery. The 3D measured accuracy of screw insertion was the primary study outcome parameter. Sixty screws inserted in 10 patients who completed the study protocol were used for the non-inferiority analysis. The non-inferiority of 3DPG was demonstrated for entry-point accuracy, as the upper margin of the 95% CI (−1.01 mm−0.49 mm) for the difference between the means did not cross the predetermined non-inferiority margin of 1 mm (p < 0.05). We also demonstrated non-inferiority of 3D angular accuracy (p < 0.05), with a 95% CI for the true difference of −2.30°−1.35°, not crossing the predetermined non-inferiority margin of 3° (p < 0.05). The results of this randomized controlled trial (RCT) showed that 3DPGs provide a non-inferior alternative to CAS in terms of screw insertion accuracy and have considerable potential as a navigational technique in spinal fixation.

An aggressive lactotroph pituitary tumor in a young male: A pituitary carcinoma without metastasis.

This case report concerns a 31-year-old male with an aggressive pituitary tumor who presented initially with bitemporal hemianopsia and slightly elevated prolactin. On magnetic resonance imaging of the brain, there was a sellar mass with parasellar invasion to the lateral aspects of the internal carotid arteries, compressing the optic chiasm. On histopathological analysis, the diagnosis was made of a densely granulated lactotroph pituitary tumor with a Ki67 proliferation rate of 15%, a mitotic count of 6/10 high-power fields, and p53 positivity. Based on these features, the tumor was classified as a grade 2b tumor according to the Trouillas classification, and a more aggressive behavior of the tumor could be expected. In order to anticipate a future need for alternative drug treatments, the following analyses were undertaken: MGMT methylation (present) as well as the expression of estrogen receptor (negative), programmed-death ligand 1 (60 - 70% positive tumor cells), vascular endothelial growth factor-A and somatostatin receptor 2 (both positive). There was regrowth of residual tumor tissue, and the treatment consisted thus far of repeat surgery, cabergoline, pasireotide, and radiotherapy. Chemotherapy with temozolomide could not yet be initiated due to a concurrent infertility treatment. This case is unique because the tumor displays atypical characteristics, both in terms of morphology and behavior. It also illustrates how pathologists can play an important role in determining the diagnosis, prognosis, and possibilities for targeted therapy.

Fluorescence-guided detection of pituitary neuroendocrine tumor (PitNET) tissue during endoscopic transsphenoidal surgery available agents, their potential, and technical aspects.

Differentiation of pituitary neuroendocrine tumor (PitNET) tissue from surrounding normal tissue during surgery is challenging. A number of fluorescent agents is available for visualization of tissue discrepancy, with the potential of improving total tumor resection. This review evaluates the availability, clinical and technical applicability of the various fluorescent agents within the field of pituitary surgery. According to PRISMA guidelines, a systematic review was performed to identify reports describing results of in vivo application of fluorescent agents. In this review, 15 publications were included. Sodium Fluorescein (FNa) was considered in two studies. The first study reported noticeable fluorescence in adenoma tissue, the second demonstrated the strongest fluorescence in non-functioning pituitary adenomas. 5-Aminolevulinic acid (5-ALA) was investigated in three studies. One study compared laser-based optical biopsy system (OBS) with photo-diagnostic filter (PD) and found that the OBS was able to detect all microadenomas, even when MRI was negative. The second study retrospectively analyzed twelve pituitary adenomas and found only one positive for fluorescence. The third investigated fifteen pituitary adenomas of which one displayed vague fluorescence. Indocyanine green (ICG) was researched in four studies with variable results. Second-Window ICG yielded no significant difference between functioning and non-functioning adenomas in one study, while a second study displayed 4 times higher fluorescence in tumor tissue than in normal tissue. In three studies, OTL38 showed potential in non-functioning pituitary adenomas. At present, evidence for fluorescent agents to benefit total resection of PitNETs is lacking. OTL38 can potentially serve as a selective fluorescent agent in non-functioning pituitary adenomas in the near future.

Detection by fluorescence of pituitary neuroendocrine tumour (PitNET) tissue during endoscopic transsphenoidal surgery using bevacizumab-800CW (DEPARTURE trial): study protocol for a non-randomised, non-blinded, single centre, feasibility and dose-finding trial.

INTRODUCTION: Achieving gross total resection and endocrine remission in pituitary neuroendocrine tumours (PitNET) can be challenging, especially in PitNETs with cavernous sinus (CS) invasion, defined as a Knosp grade of 3 or 4. A potential target to identify PitNET tissue is vascular endothelial growth factor A (VEGF-A), which expression is known to be significantly higher in PitNETs with CS invasion. METHODS AND ANALYSIS: The aim of this non-randomised, non-blinded, single centre, feasibility and dose-finding phase 1 trial is to determine the feasibility of intraoperative fluorescence imaging detection of PitNET tissue during endoscopic transsphenoidal surgery using the VEGF-A targeting optical agent bevacizumab-800CW (4, 5, 10 or 25 mg). Nine to fifteen patients with a PitNET with a Knosp grade of 3 or 4 will be included. Secondary objectives are: (1) To identify the optimal tracer dose for imaging of PitNET tissue during transsphenoidal surgery for further development in a phase 2 fluorescence molecular endoscopy trial. (2) To quantify fluorescence intensity in vivo and ex vivo with multidiameter single-fibre reflectance, single-fibre fluorescence (MDSFR/SFF) spectroscopy. (3) To correlate and validate both the in vivo and ex vivo measured fluorescence signals with histopathological analysis and immunohistochemical staining. (4) To assess the (sub)cellular location of bevacizumab-800CW by ex vivo fluorescence microscopy. Intraoperative, three imaging moments are defined to detect the fluorescent signal. The tumour-to-background ratios are defined by intraoperative fluorescence in vivo measurements including MDSFR/SFF spectroscopy data and by ex vivo back-table fluorescence imaging. After inclusion of three patients in each dose group, an interim analysis will be performed to define the optimal dose. ETHICS AND DISSEMINATION: Approval was obtained from the Medical Ethics Review Board of the University Medical Centre Groningen. Results will be disseminated through national and international journals. The participants and relevant patient support groups will be informed about the results. TRIAL REGISTRATION NUMBER: NCT04212793.

Accuracy of Patient-Specific 3D-Printed Drill Guides for Pedicle and Lateral Mass Screw Insertion: An Analysis of 76 Cervical and Thoracic Screw Trajectories.

STUDY DESIGN: Single-center retrospective case series. OBJECTIVE: The purpose of this study was to assess the safety and accuracy of three-dimensional (3D)-printed individualized drill guides for pedicle and lateral mass screw insertion in the cervical and upper-thoracic region, by comparing the preoperative 3D surgical plan with the postoperative results. SUMMARY OF BACKGROUND DATA: Posterior spinal fusion surgery can provide rigid intervertebral fixation but screw misplacement involves a high risk of neurovascular injury. However, modern spine surgeons now have tools such as virtual surgical planning and 3D-printed drill guides to facilitate spinal screw insertion. METHODS: A total of 15 patients who underwent posterior spinal fusion surgery involving patient-specific 3D-printed drill guides were included in this study. After segmentation of bone and screws, the postoperative models were superimposed onto the preoperative surgical plan. The accuracy of the realized screw trajectories was quantified by measuring the entry point and angular deviation. RESULTS: The 3D deviation analysis showed that the entry point and angular deviation over all 76 screw trajectories were 1.40 ±â€Š0.81 mm and 6.70 ±â€Š3.77°, respectively. Angular deviation was significantly higher in the sagittal plane than in the axial plane (P = 0.02). All screw positions were classified as "safe" (100%), showing no neurovascular injury, facet joint violation, or violation of the pedicle wall. CONCLUSIONS: 3D virtual planning and 3D-printed patient-specific drill guides appear to be safe and accurate for pedicle and lateral mass screw insertion in the cervical and upper-thoracic spine. The quantitative 3D deviation analyses confirmed that screw positions were accurate with respect to the 3D-surgical plan.Level of Evidence: 4.

Three-Dimensional Printed Polymethylmethacrylate Casting Molds for Posterior Fossa Reconstruction in the Surgical Treatment of Chiari I Malformation: Technical Note and Illustrative Cases.

OBJECTIVE: To describe a new method for cranial reconstruction after posterior fossa craniectomy in the surgical treatment of Chiari 1 malformation through a technical note and presentation of 3 illustrative cases. METHODS AND MATERIALS: A virtual surgical planning workflow was established for planning posterior fossa decompression, designing the suboccipital reconstruction, and manufacturing a 3D-printed polymethylmethacrylate (PMMA) casting mold. The casting accuracy was assessed by conducting a phantom experiment, and clinical data were provided by means of 3 illustrative cases. RESULTS: The accuracy of implant fabrication was found to be excellent, particularly when PMMA is introduced into the mold in a malleable state. In all 3 clinical cases, the implants were fabricated and positioned with success. Postoperative analysis revealed that accurate placement was achieved, with only minor deviation from the preoperative plan. CONCLUSIONS: 3D virtual surgical planning provides feasible tools for the planning of posterior fossa decompression and intraoperative fabrication of accurate patient-specific suboccipital cranioplasty.

Anterior Thoracic Spinal Cord Herniation: Surgical Treatment and Postoperative Course. An Individual Participant Data Meta-Analysis of 246 Cases.

BACKGROUND: Anterior thoracic spinal cord herniation (ATSCH) is a rare cause of progressive myelopathy. Early surgery is essential, but there is no agreement about the best surgical approach. OBJECTIVE: To identify factors that determine surgical results and to find evidence for the most favorable technique to correct ATSCH. METHODS: To find relevant literature, computed databases of PubMed, EMBASE, and ISI Web of Science were searched. The study comprised case reports published between 1974 and 2018, and the data set was completed with 12 cases treated in our own institute. Patient characteristics were analyzed following the principles of an individual participant data meta-analysis. RESULTS: Brown-Séquard-like neurologic deficit before surgery was associated with postoperative motor function improvement compared with patients with paraparesis (P = 0.04). In the univariate analysis, widening of the dura defect (WDD) was more prevalent among improved patients, whereas anterior dura patch and application of intraoperative neurophysiologic monitoring were not. In the multivariate analysis, the favorable association with WDD disappeared, which is explained by the dominant influence of a Brown-Séquard-like deficit on outcome. CONCLUSIONS: In general, postoperative results after surgery for ATSCH are favorable, with a high percentage of patients experiencing postoperative improvement. Postoperative motor function improvement is more likely to occur in patients with a Brown-Séquard-like neurologic deficit. The WDD should be favored above the application of a patch as the technique of choice in surgical treatment of ATSCH.

Surgery on spinal epidural metastases (SEM) in renal cell carcinoma: a plea for a new paradigm.

BACKGROUND CONTEXT: Prediction models for outcome of decompressive surgical resection of spinal epidural metastases (SEM) have in common that they have been developed for all types of SEM, irrespective of the type of primary tumor. It is our experience in clinical practice, however, that these models often fail to accurately predict outcome in the individual patient. PURPOSE: To investigate whether decision making could be optimized by applying tumor-specific prediction models. For the proof of concept, we analyzed patients with SEM from renal cell carcinoma that we have operated on. STUDY DESIGN/SETTING: Retrospective chart analysis 2006 to 2012. PATIENT SAMPLE: Twenty-one consecutive patients with symptomatic SEM of renal cell carcinoma. OUTCOME MEASURES: Predictive factors for survival. METHODS: Next to established predictive factors for survival, we analyzed the predictive value of the Motzer criteria in these patients. The Motzer criteria comprise a specific and validated risk model for survival in patients with renal cell carcinoma. RESULTS: After multivariable analysis, only Motzer intermediate (hazard ratio [HR] 17.4, 95% confidence interval [CI] 1.82-166, p=.01) and high risk (HR 39.3, 95% CI 3.10-499, p=.005) turned out to be significantly associated with survival in patients with renal cell carcinoma that we have operated on. CONCLUSIONS: In this study, we have demonstrated that decision making could have been optimized by implementing the Motzer criteria next to established prediction models. We, therefore, suggest that in future, in patients with SEM from renal cell carcinoma, the Motzer criteria are also taken into account.

Comparison of three types of treatment modalities on the outcome of fingertip injuries.

BACKGROUND: In this retrospective study, we analyzed the outcomes of different types of treatment of fingertip injuries and compared them after a mean follow-up of 4.5 years. METHODS: A total of 53 patients (59 injuries) were included in this study. The fingertip injuries were classified according to Allen classification. The patients were categorized into three groups based on the treatment: reconstructive group, bone-shortening group, and conservative group. As objective assessments, strength, sensibility, and goniometry were measured; as subjective assessments, cold intolerance, nail deformation, and aesthetics were measured. RESULTS: The mean reduction in strength, the Semmes-Weinstein monofilament test, and the reduction in mobility for the injured fingers compared with those of the uninjured finger were not significantly different between the groups. Cold intolerance was reported in 50 (84.7%) of the 59 fingers, and in almost 90% of all the cases, there was some kind of nail distortion. For the cold intolerance and nail distortions, there was no difference between the groups. The aesthetic outcomes judged by patients and surgeon were comparable. CONCLUSION: In conclusion, the outcome of treatment of Allen II, III, and IV fingertip injuries was irrespective of the treatment chosen. In an era where the enormous variety of surgical options suggests that treatment with a flap is the best, this outcome is at least surprising. LEVEL OF EVIDENCE: Therapeutic study, level IV.

A 71-year-old woman with an intracranial dural-based mesenchymal chondrosarcoma.

Intracranial mesenchymal chondrosarcoma is a rare, high-grade malignancy with the highest prevalence in young adults. Because of its rarity, most data regarding survival are limited to case studies and small series. We present a 71-year-old woman with an intracranial dural based mesenchymal chondrosarcoma located in the anterior skull base, to our knowledge the oldest patient reported with this tumor.