[IgG4 related disease presenting as panhypopituitarism and perimacular scotoma]. / Panhipopituitarismo y escotoma perimacular como presentación de enfermedad relacionada a IgG4.

IgG4-related disease (IgG4-RD) is a recently described systemic entity of unknown origin. It predominantly affects older men and has distinctive histopathologic features as storiform fibrosis, obliterative phlebitis, dense lymphoplasmacytic infiltrate with immunostaining for IgG4, and it may be associated with elevated serum levels of IgG4. Although any organ can be affected, pituitary gland is rarely involved. We describe the case of a 36-year-old man who presented with headaches, impaired vision, panhypopituitarism with diabetes insipidus and an infiltrative lesion mainly of infundibulum and pituitary. We arrived at diagnosis of IgG4-RD by pituitary biopsy. A successful response to treatment with immunosuppressive doses of corticosteroids was achieved.

[Endoscopic treatment of 140 pituitary tumors, results and complications]. / Tratamiento endoscópico de 140 tumores de hipófisis, resultados y complicaciones.

OBJECTIVE: To present the clinical and radiographic outcomes of 140 patients with pituitary adenomas treated by an endoscopic endonasal approach (EEA) over a period of 4 years. MATERIAL AND METHODS: A retrospective analysis was performed between 2011 and 2014. Pre and post operative MRI, ophtalmological assessment, endocrinological laboratory evaluation and surgical morbidity and mortality were assessed. RESULTS: 57,9% of the patients had functional tumors (n=81), acromegaly being the most frequent sub-type (29.3%). 78.6% of the lesions were macroadenomas (n=110) of which 56.4% (n=62) involved the cavernous sinus, 61 patients presented with visual field defects (44%) of which 50.8% of patients showed improvement after surgery. Gross total removal was achieved in 60% of the cases. Hormonal remission was achieved in the 75% of the patients with functional tumors. The morbidity rate was 15% and one patient died after surgery (mortality 0.7%). CONCLUSION: EEA is a safe and effective tool to treat pituitary adenomas. The main limitation for complete surgical resection is the cavernous sinus invasion.

Pathological changes of the hippocampus and cognitive dysfunction following frontal lobe surgery in a rat model.

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a known complication after intracranial surgery. Impaired hippocampal neurogenesis has been associated with cognitive dysfunction in animal models. METHODS: In order to assess hippocampal changes after brain surgery, a frontal lobe corticectomy was performed in ten adult Wistar rats (group 4). Three different control groups (n = 10 each) included no treatment (G1), general anesthesia alone (G2), and craniectomy without dural opening (G3). Twenty-four hours after surgery, half of the animals were killed, and the mRNA levels for IL-6, TNF-α, and brain-derived growth factor (BDNF) in the contralateral hippocampus were assessed by qPCR. Seven days later, the remaining animals underwent anxiety and memory testing. Afterwards, the number of immature neurons in the hippocampal cortex was measured by doublecortin (DCX) staining. RESULTS: Twenty-four hours after surgery, mRNA levels of IL-6 and TNF-α increased and BDNF decreased in both surgical groups G3 and G4 (p = 0.012). Cognitive tests demonstrated an increase in anxiety levels and memory impairment in surgical groups compared with non-surgical animals. These changes correlated with an inhibition of hippocampal neurogenesis evidenced by a decreased number of new neurons (mean ± SD for G1-4: 66.4 ± 24; 57.6 ± 22.2; 21.3 ± 3.78; 5.7 ± 1.05, p < 0.001, non-parametric ANOVA). CONCLUSIONS: Intracranial surgery was demonstrated to induce an inflammatory reaction within the hippocampus that compromised neurogenesis and impaired normal cognitive processing. Corticectomy had a greater effect than craniotomy alone, indicating a central trigger for hippocampal inflammatory changes. POCD after craniotomy may originate from a central inflammatory response resulting from surgical trauma to the brain parenchyma.

Unsuccessful pulsed radiofrequency of the sphenopalatine ganglion in patients with chronic cluster headache and subsequent successful thermocoagulation.

We present the results of pulsed and continuous radiofrequency (CRF) of the sphenopalatine ganglion in a case series of 3 patients with chronic cluster headache (CCH). Three patients were referred to our neurosurgical department because of CCH, which was refractory to pharmacological treatment. They underwent pulsed radiofrequency of the sphenopalatine ganglion (PRF-SPG), and the procedure was performed through an infrazygomatic approach. In the PRF procedures, we applied 2 cycles of PRF at 42°C and 45 V for 120 seconds, with a pulse frequency of 2 Hz and a pulse width of 20 ms. In those procedures where thermocoagulation was carried out, 2 CRF lesions at 80°C for 90 seconds each were performed. Following corticosteroid and local anesthetic (40 mg of methylprednisolone and 1 mL of 1% lidocaine) injection, 2 patients had no pain relief at all, whereas the third one experienced a partial response, which lasted only 1 month and his pain then returned to its baseline level. Thus, this outcome was assessed as a nonsustained partial response. Therefore, all of them underwent a CRF lesioning of the SPG, and after this procedure, they achieved complete pain relief until the end of the follow-up period. Furthermore, the associated autonomic manifestations disappeared. The 3 patients presented in this case series failed to achieve adequate pain relief after PRF-SPG. However, these same patients subsequently underwent a successful CRF of the SPG.

Minimally Invasive Drainage of Intracerebral Hemorrhage. A South American Experience with the MISTIE Procedure.

BACKGROUND: Intracerebral hemorrhage (ICH) is the second most common subtype of stroke but is associated with greater rates of disability or mortality. One of the factors of a poor prognosis is large hematoma volume. The MISTIE III trial with the aim of decreasing clot size showed that the greater the ICH reduction, the higher likelihood of lower mortality without a net increase in the proportion of patients with severe disability. Our aim is to describe our experience with treating selective patients with ICH per the MISTIE trial protocol in a university hospital in Argentina during 4 years. METHODS: A retrospective analysis was performed of consecutive patients with ICH treated at a single university tertiary-care center from 2017 to 2021 with the MISTIE protocol. RESULTS: We deployed this procedure in 7 patients with a median age of 61 years, median National Institutes of Health Stroke Scale score of 14, an ICH volume of 35 mL and median ICH score of 2. Five of 7 patients achieved the target goal of hematoma reduction; 4 of the patients had a total independence level and 1 needed minimal help at 12 months after discharge. Five patients had a good functional outcome (modified Rankin Scale score 0-3 and extended Glasgow Outcome Scale score 4-8) and 2 patients had died but neither because of consequences of thrombolysis of the intracerebral hemorrhage. We did not find bleeding complications during catheter placement, alteplase infusion, or after catheter removal. CONCLUSIONS: The procedure can be carried out safely in Latin American centers that have experience in managing neurocritical patients.

Safety margin for the preservation of the nasoseptal artery during trans-nasal endoscopic approach.

BACKGROUND: The introduction of the nasoseptal flap for the reconstruction of extended endoscopic approaches decreased the incidence of postoperative fistula. In order to preserve the septal vascular pedicles, many have started to prepare the flap systematically, prior to the opening of the sphenoid rostrum. The aim of this study is to obtain an average measure of the location of the posterior septal artery using the upper edge of the choana as a landmark. METHODS: Ten cadaveric heads, fixed with formaldehyde and injected with colored silicone, were studied. The course, branching pattern and dominance of the branches of the posterior septal artery were recognized, as well as the distance in of its superior and lower branches respect to the medial upper edge of the choana. RESULTS: In all cases, the posterior septal artery enters as an only vessel through the sphenopalatine foramen. In its sphenoid segment, over the sphenoid rostrum, the posterior septal artery divides into its upper and lower branches, in most cases, laterally to the sphenoid ostium (70%, N.=14). The lower branch was dominant in 60% of the cases (N.=12). Regarding the mean distance in millimeters from the medial upper edge of the choana to the superior branch, it was 14.45±0.4102 (18-11.5) and, to the lower branch, 10.9±0.4682 (14-7). CONCLUSIONS: A rostrum opening to 15 mm over the upper edge of the choana is safe to avoid vascular complications, and to be able to prepare a viable nasoseptal flap only if it is necessary.

Navigated multiplanar osteotomies for spinal primary bone tumors.

BACKGROUND: Establishing the proper diagnosis and rendering appropriate treatment of spinal primary bone tumors (SPBT) can result in definitive cures. Notably, malignant, or benign SPBT (i.e., with aggressive local behavior) generally require en bloc resection. Osteotomies of the vertebral body in more than 1 plane may avoid critical structures, preserve nerve functions, and reduce the volume of healthy bone resected. Here, our objective was to report how we planned and performed navigated multiplanar osteotomies for en bloc resection of 14 SPBT. METHODS: We performed a retrospective analysis of 14 patients with malignant or locally aggressive benign SPBT operated on consecutively between 2014 and 2019 utilizing preoperative 3D planning/navigation. Tumors were resected in an en bloc fashion utilizing multiplanar osteotomies. Patients were followed for a minimum of 12 postoperative months. RESULTS: Diagnoses included three benign but locally aggressive bone tumors (i.e., all osteoblastomas) and 11 primary sarcomas (i.e., six chordomas and five chondrosarcomas). Eleven tumors involved the sacrum and the other three, the thoracic spine. In 12 patients, the en bloc margins were classified as marginal (<1 cm), and in two patients, as wide (>1 cm). Intraoperative navigation facilitated the performance of 40 osteotomies in 14 patients (median = 2.9, range = 2-6). CONCLUSION: Navigated multiplanar osteotomies increased the precision and safety of en bloc resections for 14 primary spinal bone tumors SPBT that included 11 malignant and three benign/locally aggressive lesions.

Surgical Indication Optimization of Brain Metastases Based on the Evolutionary Analysis of Karnofsky Performance Status.

BACKGROUND AND OBJECTIVE: Surgical resection of brain metastases (BM) offers the highest rates of local control and survival; however, it is reserved for patients with good functional status. In particular, the presence of BM tends to oversize the detriment of the overall functional status, causing neurologic deterioration, potentially reversible following symptomatic pharmacological treatment. Thus, a timely indication of surgical resection may be dismissed. We propose to identify and quantify these variations in the functional status of patients with symptomatic BM to optimize the indication of surgical resection. PATIENTS AND METHODS: Historic, retrospective cohort analysis of adult patients undergoing BM microsurgical resection, consecutively from January 2012 to May 2016, was conducted. The Karnofsky performance status (KPS) variation was recorded according to the symptomatic evolution of each patient at specific moments of the diagnostic-therapeutic algorithm. Finally, survival curves were delineated for the main identified factors. RESULTS: One hundred and nineteen resection surgeries were performed. The median overall survival was 243 days, while on average it was 305.7 (95% confidence interval [CI]: 250.6-360.9) days. The indication of surgical resection of 10% of the symptomatic patients in our series (7.5% of overall) could have been initially rejected due to pharmacologically reversible neurologic impairment. Survival curves showed statistically significant differences when KPS was stratified following pharmacological symptomatic treatment (p < 0.0001), unlike when they were estimated at the time of BM diagnosis (p = 0.1128). CONCLUSION: The preoperative determination of the functional status by KPS as an evolutive parameter after the nononcologic symptomatic pharmacological treatment allowed us to optimize the surgical indication of patients with symptomatic BM.

Fungal cerebral abscess in a diabetic patient successfully treated with surgery followed by prolonged antifungal therapy.

BACKGROUND: Intracranial fungal masses are uncommon diseases, but their incidence is increasing, most often due to the prolonged survival of patients with different immunodeficiencies. The management of patients with intracranial fungal masses included stereotactic biopsy for diagnosis, partial or radical surgery excision and prolonged antifungal therapy. AIMS: We report the case of a 51-year-old diabetic man with a history of psoas abscess due to Candida albicans 1 year before the onset of neurological symptoms, including headache and generalized tonoclonic seizures. METHODS: Magnetic resonance imaging showed a single lesion located in the right parietal lobe with mass effect, surrounding edema and enhancement after injection of gadolinium. The material was purulent. RESULTS: Direct microscopic examination showed hyaline, branched and septate hyphae compatible with fungal elements. CONCLUSIONS: Fungal infections, especially due to Candida species, should be considered in diabetic patients with parenchymal brain abscesses. Radical excision followed by prolonged antifungal therapy based on fluconazole or amphotericin B is necessary to improve the prognosis of this type of patients.

Early Report on the Impact of COVID-19 Outbreak in Neurosurgical Practice Among Members of the Latin American Federation of Neurosurgical Societies.

BACKGROUND: The COVID-19 pandemic has caused severe economic consequences by local governmental measures to contain the outbreak. We provide insight on the impact that health care restriction has made on neurosurgical activity in Latin Iberoamerica. METHODS: We performed an internet-based survey among presidents and members of the societies of the Latin American Federation of Neurosurgical Societies (FLANC). We blindly analyzed information regarding local conditions and their impact on neurosurgical praxis using SPSS software. RESULTS: Information came from 21 countries. Sixteen society presidents reported having suspended regular activities and deferring local scheduled congresses, 14 reported mandatory isolation by government, and 4 instituted a telemedicine project. Four-hundred eighty-six colleagues, mean age 49 years, reported a mean 79% reduction in their neurosurgical praxis. Seventy-six percent of neurosurgeons have savings to self-support for 3-6 months if restrictions are long lasting. CONCLUSIONS: Stopping activities among societies of the FLANC, together with a drop of 79% of neurosurgical praxis, adds to deficits in provider's protection equipment and increasing demand for attention in the health care systems, representing a huge financial risk to their sustainability. Neurosurgeons should be involved in local policies to protect health and economy. Telemedicine represents an excellent solution, avoiding another pandemic of severe diseases across all-specialties as nonessential care can turn essential if left untreated. Financial support and ethics code review is needed to battle this new disease, designated the occupational disease of the decade, that continues to scrag the health care system. Times of crisis are times of great opportunities for humanity to evolve.

Lateral Transpsoas Approach for Lumbar Indirect Lateral Recess Decompression: 2-Dimensional Operative Video.

Neurogenic claudication is a common symptom of lumbar spinal stenosis; its pathophysiology is thought to be ischemia of the nerve roots secondary to compression from surrounding structures. The stenosis of the lateral recesses and neuroforamen can cause these symptoms and its surgical treatment is decompression. The placement of interbody cages that restore the disc space height may indirectly decompress the neuroforamen and alleviate the nerve impingement symptoms. In case of concomitant low-grade spondylolisthesis, interbody devices might also reduce the slippage. We present a technical surgical video of a minimally invasive lateral transpsoas fusion, relying on indirect decompression to treat a patient with neurogenic claudication secondary to grade 1 spondylolisthesis. The patient signed a written consent to publish a video, recording, photograph, image, illustration, and/or information about him.

Minimally Invasive Single-Stage Removal of a Thoracic Dumbbell Tumor from a Posterior Approach: 2-Dimensional Operative Video.

Dumbbell-shaped thoracic tumors usually involve the spinal canal and the posterior thoracic cavity. Gross total resection is the treatment of choice, but techniques for surgical excision remain controversial. An anterolateral transthoracic approach may remove the paravertebral component of the tumor, but has limited or no control of the intracanal lesion. A combined posteroanterior approach requires a 2-stage surgery with significant morbidity. The preferred approach depends mainly on the tumor location, size, shape, and its specific anatomical relationship with the surrounding vital structures. We present a surgical video of a single-stage posterior minimally invasive approach for the management of a thoracic dumbbell tumor.

[Minimally invasive resection of spinal synovial cysts: Technical note]. / Resección mínimamente invasiva de quistes sinoviales espinales. Nota técnica.

OBJECTIVE: To present the treatment algorithm, surgical technique, and results of a series of patients with spinal synovial cysts operated with minimally invasive techniques (MIS). INTRODUCTION: Spinal synovial cysts originate from the dilation and potential rupture of the synovial sheath of a facet joint. Surgical resection is considered the treatment of choice in symptomatic patients. The use of MIS techniques could reduce the disruption of the facet joint involved, reducing the risk of postoperative instability. MATERIALS AND METHODS: We retrospectively evaluated 21 patients with spinal synovial cysts operated by MIS approach and decompression. We analyzed the signs, symptoms, surgical time, hospital stay, evolution, and complications. The visual analog scale (VAS) was used to evaluate pain and the Weiner scale and the modified Macnab criteria to measure the patient's postoperative satisfaction. RESULTS: A total of 21 patients were surgically treated with MIS technique; 76.2% (n = 16) did not require arthrodesis, the remaining 23.8% (n = 5) were fused. We performed 13 (61.9%) contralateral hemilaminectomies, 7 ipsilateral hemilaminectomies (33.3%), and 1 laminectomy in S1-S2. The average follow-up was 26 months; surgical time was 150.33 ± 63.31 min, with a hospital stay of 2.5 ± 1.78 days. The VAS decreased from 8.3 preoperatively to 2.3 postoperatively. Sixteen patients reported excellent results, four good and one regular in the scale of Macnab. 95.2% of patients perceived that the procedure was very/quite successful according to the Weiner scale. CONCLUSION: The minimally invasive approach is a safe and effective procedure for the complete resection of spinal synovial cysts. It provides excellent clinical-functional results by preserving muscles, ligaments, and joint facets.

Minimally Invasive Resection of a Cervical Anterolateral Meningioma: 2-Dimensional Operative Video.

Intradural extramedullary spinal tumors were historically managed through traditional midline approaches. Although conventional laminectomy or laminoplasty provides a wide tumor and spinal cord exposure, they may cause prolonged postoperative neck pain and late kyphosis deformity. Minimally invasive ipsilateral hemilaminectomy preserves midline structures, reduces the paraspinal muscle disruption, and could avoid postoperative kyphosis deformity. A safe tumor resection through this approach could be complicated in large sized or anteromedullary located lesions. We present a surgical video of C3 antero located meningioma removed en bloc through a minimally invasive approach. The patient signed a written consent to publish video, recording, photograph, image, illustration, and/or information about him.

[Usefulness of minimally invasive spine surgery for the management of thoracolumbar spinal metastases]. / Utilidad de la cirugía espinal mínimamente invasiva en el manejo de las metástasis espinales toraco-lumbares.

OBJECTIVE: To describe the surgical results and evolution of patients who underwent minimally invasive spine surgery (MISS) for the treatment of thoracolumbar spinal metastases, using the NOMS (Neurological, Oncological, Mechanical, Systemic) assessment for the therapeutic decision. METHODS: Patients who underwent MISS technique for the treatment of thoracolumbar spinal metastases were prospectively enrolled at the Hospital Italiano de Buenos Aires, from June 2014 to June 2017. In all cases, the NOMS assessments were performed for therapeutic decision making. Surgical results were analyzed in terms of improvements in Karnofsky performance status, pain relief (VAS - visual analog scale), Frankel, blood loss, need for transfusions, complications, use of opioids and hospitalization length. A P < 0.05 value was considered statistically significant. RESULTS: During the study period 26 patients were included, 13 of them were women. The average age was 57-year-old (27-83 years). Breast cancer was the most frequent primary tumor (27%). The main symptom was pain (96%), although 12 patients presented with myelopathy (46%). High-grade epidural spinal cord compression requiring decompression was observed in 17 cases (65%). According to the SINS (spinal instability neoplastic score), most lesions were potentially unstable or unstable (89%) requiring MISS stabilization. After surgery, pain relief (VAS) and neurological recovery (Frankel) improved significantly in the 77% and 67% of the cases, respectively, with low intraoperative blood loss and without any transfusions. Only one minor surgical complication was presented (4%). The average of hospital stay was 5.5 days. CONCLUSION: In our series and using the NOMS as a therapeutic algorithm, MISS was effective for decompression and spinal stabilization, with a low rate of complications and rapid postoperative recovery.

Accuracy in Percutaneous Transpedicular Screws Placement Using Biplane Radioscopy: Systematic Review and Meta-Analysis.

STUDY DESIGN: Systematic review and descriptive data meta-analysis. OBJECTIVE: The objective of this study was to appropriately establish the accuracy in the percutaneous transpedicular screws (PTS) placement using biplane radioscopy (Rx-2D). SUMMARY OF BACKGROUND DATA: The Rx-2D is a widely-used technique for PTS as it is practical, ubiquitous, and cost-effective. However, the reported "acceptable" accuracy attained by this method is widely variable ranging between 76% and 100%. METHODS: A systematic review was conducted to screen publications about PTS placement using Rx-2D guidance. PubMed/MEDLINE database was consulted using the search term "percutaneous pedicle screw" from 1977 to 2017. Previous meta-analysis and reference lists of the selected articles were reviewed. Accuracy values were assessed fulfilling the proposed criteria. Observational data meta-analysis was performed. Cochran's Q test was used to determine heterogeneity among data extracted from the series, which was quantified by I test. P-values≤0.05 were considered statistically significant. The results were depicted by Forest plots. Funnel plots were outlined to visualize a possible bias of publication among the selected articles. RESULTS: In total, 27 articles were included in the analysis. Results of the accuracy were as follow, 91.5% (n=7993; 95% CI, 89.3%-93.6%) of the screws were placed purely intrapedicular, and 96.1% (n=8579; 95% CI, 94.0%-98.2%) when deviation from the pedicle was up to 2 mm. CONCLUSIONS: This meta-analysis is the largest review of PTS placed with Rx-2D guidance reported up to date. We concluded that the procedure is a safe and reproducible technique. The key values obtained in this work set reliable references for both clinical and training outcome assessing.

Flow Diverter for the Treatment of Pseudoaneurysms of the Extracraneal Vertebral Artery: Report of Two Cases and Review of the Literature.

BACKGROUND: Pseudoaneurysms (PAs) of the extracranial vertebral artery (VA) are rare lesions, representing less than 1% of all aneurysms. Although these lesions may resolve spontaneously, they present a high rupture rate, so early preventive treatment is advised. CASE DESCRIPTION: Case 1: A 48-year-old woman presented with pain and cervical rigidity. An angiotomography showed a PA of the left VA at the level of the C2 transverse foramen, with mural thrombosis and bone remodeling of the left lateral mass. The PA was treated with the endovascular placement of a flow diverter stent. The patient was discharged 3 days after the procedure without complications. The last vascular imaging follow-up was performed 6 years after the procedure showing a patent left VA, with complete resolution of the aneurysm. Case 2: A 57-year-old woman was admitted referring cervicalgia after a polytraumatism. An angiotomography revealed a fracture of the C1 posterior arch, lateral mass, and left transverse foramen, on top of a left VA thrombosis due to a vascular dissection. Eleven months after the trauma, a left VA V3 segment arteriovenous fistula developed. It was treated with hydrocoils, with no complications. One month after the embolization, a left VA V3 segment PA was observed and treated with a flow diverter stent. An angiographic follow-up 2 years after the procedure showed a patent left VA, with complete resolution of the PA. CONCLUSION: The use of flow diverters seems to be a safe and effective therapeutic option for the treatment of PAs of the extracranial VAs.

[Stereotactic brain biopsy in the diagnosis of focal brain lesions in AIDS]. / La biopsia estereotáctica en el diagnóstico de las lesiones cerebrales focales en sida.

Focal brain lesions are frequent complications among HIV/AIDS patients. Between January 1999 and May 2007, 83 procedures of stereotactic brain biopsies in HIV/AIDS patients with focal cerebral lesions were carried out. The inclusion criteria were lack of response to current diagnostic and therapeutic guidelines for brain lesions. All the samples underwent microscopic evaluation during surgery to assert valid material and delayed histopathological and microbiological examination. Forty one patient images demonstrated multiple brain lesions. Sixty two cases had supratentorial localization, 4 lesions were located beneath the tentorium and 17 showed both settings. Fifty one lesions presented peripheral enhancement after contrast computed tomography (CT) or magnetic resonance imaging (MRI). A 100% of useful samples recovery was achieved. Progressive multifocal leucoencephalopathy (PML) was the most frequent diagnosis (29%), followed by primary central nervous system lymphoma (PCNSL) (23%), and toxoplasmosis (15.7%). Statistically significant association was observed between histopathological diagnosis and lesion location and between those and peripheral ring enhancement images. The positive diagnostic rate of the invasive procedure was 90.3%. The morbidity/mortality rate was 2.4% in this series. In conclusion, the stereotactic brain biopsy ordered early during the patient's evolution showed a good performance in order to achieve a prompt and accurate diagnosis and to guide the therapeutic scheme in these AIDS patients with focal brain lesions.

Application of Fibrin Rich in Leukocytes and Platelets in the Reconstruction of Endoscopic Approaches to the Skull Base.

BACKGROUND: The objective of this work is to report the feasibility and results of an institutional protocol for the application of an innovative biologically active hemoderivative autologous material, denominated leukocyte- and platelet-rich fibrin (L-PRF), in the reconstruction of endoscopic approaches to the sellar region. METHODS: L-PRF membranes were produced from centrifuged autologous venous blood. They were used for the reconstruction of transsphenoidal endoscopic approaches to the sellar region in 12 patients. The trophism of the mucosa was monitored during the first 30 days by means of fiberoptic endoscopic controls on the second and seventh postoperative days. Follow-up was performed to rule out complications up to 30 postoperatively days. RESULTS: The product obtained bore the characteristics of the original descriptions of L-PRF. Standardized preparation of L-PRF membranes promoted early regeneration of the sphenoid sinus mucosa to close endoscopic approaches to the sellar region. No complications within the first 30 postsurgical days were reported. CONCLUSIONS: L-PRF membranes offer characteristics that are superior to other techniques and products, mainly because of their role as biological promoters of tissue regeneration, their low economic cost, and immediate availability. However, it would be necessary to confirm these results in studies involving more patients.

[Minimally invasive extraforaminal lumbar interbody fusion]. / Fusión intersomática lumbar extraforaminal mínimamente invasiva.

OBJECTIVES: The objective of the present study was to determine the indications, surgical technique, results, and complications of minimally invasive extraforaminal lumbar interbody fusion (ELIF). INTRODUCTION: ELIF is characterized as removal of the superior articular process (SAP) to access the intra-canalicular root and disc through Kambin's triangle. METHODS: A retrospective study was conducted of 40 patients operated upon between 2013 and 2015. Patients with low back pain or root pain due to degenerative disc disease, spondylolisthesis grade 1 and 2, recurrent disc herniation, and recess-foraminal stenosis were included. A visual analogue scale (VAS), the Oswestry index, the Weiner scale and the modified MacNab criteria were used to assess pain, clinical and functional results and patient satisfaction one year after surgery. Complications were documented and rated according to their severity, in four degrees. RESULTS: We operated on 25 women and 15 men of average age 57 years. Of the forty, 47.5% were treated for spondylolisthesis, 25% by recess foraminal stenosis. In total, 54 interbody cages and 188 percutaneous pedicle screws were placed; and the mean duration of surgery was 245 (±25.4) minutes. The mean hospitalization time was 3.5 (±0.49) days. We observed nine Grade 1 and one Grade 2 complication. The mean preoperative ODI score was 51.9 ± 4.96, which improved to 12.2 ± 3.19 at one year (P < 0.0001). The mean VAS low back pain rating improved from 8.81 ± 0.62 to 2.12 ± 0.89 (P < 0.0001). By one year post-operatively, 77.5% of the patients had fusion (Bridwell grade 1 or 2). CONCLUSIONS: ELIF is a safe and effective surgical approach. Satisfactory clinical outcomes, comparable to traditional techniques, can be achieved with facet resection limited to the superior articular process.