Intraoperative cell salvage in revision hip arthroplasty.

Aims: The aim of this study was to perform a systematic review of the evidence for the use of intraoperative cell salvage in patients undergoing revision hip arthroplasty, and specifically to analyze the available data in order to quantify any associated reduction in the use of allogenic blood transfusion, and the volume which is used. Methods: An electronic search of MEDLINE (PubMed), Embase, Scopus, and the Cochrane Library was completed from the date of their inception to 24 February 2022, using a search strategy and protocol created in conjunction with the PRISMA statement. Inclusion criteria were patients aged > 18 years who underwent revision hip arthroplasty when cell salvage was used. Studies in which pre-donated red blood cells were used were excluded. A meta-analysis was also performed using a random effects model with significance set at p = 0.05. Results: Of the 283 studies which were identified, 11 were included in the systematic review, and nine in the meta-analysis. There was a significant difference (p < 0.001) in the proportion of patients requiring allogenic transfusion between groups, with an odds ratio of 0.331 (95% confidence interval (CI) 0.165 to 0.663) associated with the use of cell salvage. For a total of 561 patients undergoing revision hip arthroplasty who were treated with cell salvage, 247 (44.0%) required allogenic transfusion compared with 418 of 643 patients (65.0%) who were treated without cell salvage. For those treated with cell salvage, the mean volume of allogenic blood which was required was 1.95 units (390 ml) per patient (0.7 to 4.5 units), compared with 3.25 units (650 ml) per patient (1.2 to 7.0 units) in those treated without cell salvage. The mean difference of -1.91 units (95% CI -4.0 to 0.2) in the meta-analysis was also significant (p = 0.003). Conclusion: We found a a significant reduction in the need for allogenic blood transfusion when cell salvage was used in patients undergoing revision hip arthroplasty, supporting its routine use in these patients. Further research is required to determine whether this effect is associated with types of revision arthroplasty of differing complexity.

Olfactomedin-4 + neutrophils exacerbate intestinal epithelial damage and worsen host survival after Clostridioides difficile infection.

Neutrophils are key first responders to Clostridioides difficile infection (CDI). Excessive tissue and blood neutrophils are associated with worse histopathology and adverse outcomes, however their functional role during CDI remains poorly defined. Utilizing intestinal epithelial cell (IEC)-neutrophil co-cultures and a pre-clinical animal model of CDI, we show that neutrophils exacerbate C. difficile -induced IEC injury. We utilized cutting-edge single-cell transcriptomics to illuminate neutrophil subtypes and biological pathways that could exacerbate CDI-associated IEC damage. As such, we have established the first transcriptomics atlas of bone marrow (BM), blood, and colonic neutrophils after CDI. We found that CDI altered the developmental trajectory of BM and blood neutrophils towards populations that exhibit gene signatures associated with pro-inflammatory responses and neutrophil-mediated tissue damage. Similarly, the transcriptomic signature of colonic neutrophils was consistent with hyper-inflammatory and highly differentiated cells that had amplified expression of cytokine-mediated signaling and degranulation priming genes. One of the top 10 variable features in colonic neutrophils was the gene for neutrophil glycoprotein, Olfactomedin 4 (OLFM4). CDI enhanced OLFM4 mRNA and protein expression in neutrophils, and OLFM4 + cells aggregated to areas of severe IEC damage. Compared to uninfected controls, both humans and mice with CDI had higher concentrations of circulating OLFM4; and in mice, OLFM4 deficiency resulted in faster recovery and better survival after infection. Collectively, these studies provide novel insights into neutrophil-mediated pathology after CDI and highlight the pathogenic role of OLFM4 + neutrophils in regulating CDI-induced IEC damage. One Sentence Summary: Utilizing single-cell transcriptomics, IEC-epithelial co-cultures, and pre-clinical models of CDI, we have identified a subset of neutrophils that are marked by OLFM4 expression as pathogenic determinants of IEC barrier damage after CDI.

The Exeter Trauma Stem: A radiographic follow-up at minimum of five years post implantation.

INTRODUCTION: The Exeter Trauma Stem (ETS) has been recommended by National Institute of Clinical Excellence (NICE) guidelines in the United Kingdom as a proven, cemented stem. A single laboratory study in the literature has raised possible concerns about the polished finish of the ETS and subsequent potential for accelerated loosening although there is little clinical evidence to support or refute this. METHODS: The aim of this study was to assess clinical outcomes of the ETS at a minimum of five years post implantation. Primary outcomes were radiological loosening at a minimum of five years along with survivorship of the implant. Patient demographics were prospectively collected and followed up. RESULTS: 218 ETS's (in 214 patients) were implanted from June 2002 until August 2008 in a single centre by a wide variety of surgeons of differing grades. Of these, 16 underwent revision surgery for fracture (2), dislocation (3), infection (1) and acetabular erosion (10) but there were no revisions for aseptic loosening of the implant. There were 64.0% (137/214) patients that had died by the time of this study. Of the remaining patients, 90 had radiographs of their hips at a minimum of 5 years with 36 of these at a minimum of 7 years post implantation. None of these had evidence of loosening. CONCLUSION: The ETS is a robust and suitable stem for implantation in patients with hip fractures. There are no clinical suspicions or increased rates of loosening with the ETS in our study. The concerns about surface finish are not borne out in our clinical study which shows no evidence of loosening at a minimum of five years post operation. It confers many advantages including ease of revision and it should continue to be used as per NICE guidelines.

The Lateral Meniscus as a Guide to Anatomical Tibial Tunnel Placement During Anterior Cruciate Ligament Reconstruction.

PURPOSE: The aim of the study is to show, on an MRI scan, that the posterior border of the anterior horn of the lateral meniscus (AHLM) could guide tibial tunnel position in the sagittal plane and provide anatomical graft position. METHOD: One hundred MRI scans were analysed with normal cruciate ligaments and no evidence of meniscal injury. We measured the distance between the posterior border of the AHLM and the midpoint of the ACL by superimposing sagittal images. RESULTS: The mean distance between the posterior border of the AHLM and the ACL midpoint was -0.1mm (i.e. 0.1mm posterior to the ACL midpoint). The range was 5mm to -4.6mm. The median value was 0.0mm. 95% confidence interval was from -0.5 to 0.3mm. A normal, parametric distribution was observed and Intra- and inter-observer variability showed significant correlation (p<0.05) using Pearsons Correlation test (intra-observer) and Interclass correlation (inter-observer). CONCLUSION: Using the posterior border of the AHLM is a reproducible and anatomical marker for the midpoint of the ACL footprint in the majority of cases. It can be used intra-operatively as a guide for tibial tunnel insertion and graft placement allowing anatomical reconstruction. There will inevitably be some anatomical variation. Pre-operative MRI assessment of the relationship between AHLM and ACL footprint is advised to improve surgical planning. LEVEL OF EVIDENCE: Level 4.

Endoscopic endonasal approach for the treatment of schwannomas of the pterygopalatine fossa: case report and review of the literature.

INTRODUCTION: Pterygopalatine fossa (PPF) schwannomas are rare lesions most often arising from branches of the trigeminal nerve. Symptomatic lesions have been traditionally treated by conventional external approaches. However, the development of an expanded endonasal approach (EEA) enables skull base surgeons to reach these deeply seated lesions via a different route with its own advantages and drawbacks. METHODS: Case report and review of the literature. CASE DESCRIPTION: A 41-year-old woman presented with a 6-year history of right facial pain and numbness. Her symptoms had increased progressively over a year, and she recently had developed right-sided otalgia. MRI revealed a right PPF mass, hypointense on T1 and T2 sequences with homogeneous enhancement following the use of gadolinium. A biopsy, attempted at another institution, was considered non-diagnostic. We totally removed the lesion through an endoscopic endonasal transmaxillary approach. Final pathology confirmed the diagnosis of schwannoma. Post-operatively, the patient noted a significant improvement of her facial pain (V2 territory). CONCLUSION: The endonasal endoscopic transmaxillary approach provides adequate access to the PPF, thus enabling safe tumor removal with less morbidity than conventional routes.

Emergency department staff views and experiences on diagnostic overshadowing related to people with mental illness.

Aims. To investigate recognition of diagnostic overshadowing, i.e., misattribution of physical symptoms to mental illness, among emergency medicine professionals; further, to identify contributory and mitigating factors to diagnostic overshadowing. Methods. In-depth individual interviews of 25 emergency department clinicians and qualitative analysis using thematic analysis. Results. Diagnostic overshadowing was described as a significant issue. Contributing factors included: (1) problems of knowledge and information gathering; (2) clinicians' attitudes toward people with mental illness, substance misuse and frequent attenders; and (3) difficulties in working with mental health services in the context of a 4-h target for discharge from the emergency department. Avoidance of patients with a psychiatric diagnosis was also described, due to fear of violence. Conclusion. The physical health care of people with mental illness in emergency departments may be adversely affected by diagnostic overshadowing and avoidance by clinical staff, along with difficulties created by the illness, medication and the emergency department environment. Greater joint working between psychiatric and emergency department staff is suggested as one way to reduce diagnostic overshadowing.

Displaced femoral neck stress fractures in Royal Marine recruits--management and results of operative treatment.

Femoral neck stress fractures (FNSF) represent 3.5%-8% of stress fractures in military recruits; potentially resulting in medical discharge and/or complications. The incidence of displaced FNSF in the British Army has been reported as 1.8 in 10,000 recruits. We aimed to review the incidence and outcome of displaced FNSF in Royal Marine recruits. Retrospective review identified 6 recruits who sustained a displaced FNSF from 2001 to 2011 representing an incidence of 9.3 in 10,000 recruits. All were treated urgently by internal fixation. There were no cases of avascular necrosis, no surgical complications and no further procedures required. All united with a mean time to union of 11 months. 50% had a union time greater than 1 year. These fractures are slow to unite but with urgent surgical intervention and stable fixation 100% union was achieved. Awareness of this guides the management and rehabilitation whilst avoiding the risks of unnecessary secondary surgical interventions.

The supraorbital approach for recurrent or residual suprasellar tumors.

BACKGROUND: Suprasellar tumors can be removed through a variety of approaches including conventional frontotemporal craniotomies, the transsphenoidal route, or the supraorbital (SO) eyebrow craniotomy. Herein we assess the utility of the SO route for recurrent or residual suprasellar tumors previously treated by an alternative route. MATERIAL AND METHODS: A retrospective analysis of all consecutive patients who underwent an SO approach for removal of a recurrent/residual tumor was undertaken. RESULTS: Between December 2007 and February 2010, 11 patients underwent an SO craniotomy for a recurrent or growing residual tuberculum sellae meningioma (n=7) or craniopharyngioma (n=4). All 11 patients had prior craniotomies, 5 had transsphenoidal surgery, 6 had radiation treatment, and 1 had chemotherapy. In the last 5 cases, the endoscope was used in addition to the microscope for intraoperative visualization. 3 patients underwent decompression of multicystic craniopharyngiomas and the remaining 8 patients had tumor debulking, all achieving 70% or more tumor removal. Of 9 patients with preoperative visual deterioration, 6 (67%) had improvement and no patient had visual worsening. No new adenohypophysis or neurohypophysis dysfunction was noted. One patient had a postoperative CSF leak requiring reoperation. CONCLUSION: The SO approach should be considered as a safe and effective alternative route for recurrent or residual suprasellar tumors previously treated by conventional craniotomy or TS surgery. It typically offers a simplified trajectory that minimizes scar tissue from prior approaches and provides excellent access for optic apparatus decompression. Endoscopy is helpful to visualize hidden tumor remnants and maximize safe tumor removal.

Vidian nerve neurofibroma removed via a transpterygoid approach.

BACKGROUND: Lesions originating in the vidian canal are extremely rare. Most frequently, they are extensions from contiguous carcinomas. We present a rare case of a vidian nerve neurofibroma and discuss its surgical management. CASE REPORT: A 62-year-old woman with a history of a basal cell skin cancer was evaluated for bilateral tinnitus. Imaging revealed a left-sided lesion at the medial aspect of the pterygoid process base, over the vidian canal. Under image-guidance, an endonasal endoscopic transpterygoid approach was performed. The histopathological examination supported the diagnosis of neurofibroma. CONCLUSION: Benign nerve sheath tumors of the vidian nerve should be considered in the differential diagnosis of a vidian canal lesion. Given the propensity of more aggressive tumors, a tissue diagnosis should be warranted in order to coordinate appropriate subsequent treatment. The expanded endonasal transpterygoid approach offers a safe, less invasive, and effective route to perform the excisional biopsy of such a lesion.

Development and responsiveness of a scale to measure clinicians' attitudes to people with mental illness (medical student version).

OBJECTIVE: We report the rationale, reliability, validity and responsiveness studies of the Mental Illness: Clinicians' Attitudes (MICA) Scale, a 16-item scale designed to measure attitudes of health care professionals towards people with mental illness. METHOD: Items were generated through focus groups with service users, carers, medical students and trainee psychiatrists. Psychometric testing was completed in a number of student samples. The responsiveness of the scale was tested after a 1.5 h mental illness stigma related intervention with medical students. RESULTS: The MICA scale showed good internal consistency, alpha = 0.79. The test-retest reliability (concordance) was 0.80 (95% CI: 0.68-0.91). The standardised response mean for the scale was 0.4 (95% CI 0.02-0.8) after a mental illness related stigma intervention. CONCLUSION: The MICA scale is a responsive, reliable and valid tool, which can be used in medical education and mental health promotion settings and studies.

Animal model for endoscopic neurosurgical training: technical note.

OBJECTIVE: The learning curve for endonasal endoscopic and neuroendoscopic port surgery is long and often associated with an increase in complication rates as surgeons gain experience. We present an animal model for laboratory training aiming to encourage the young generation of neurosurgeons to pursue proficiency in endoscopic neurosurgical techniques. METHODS: 20 Wistar rats were used as models. The animals were introduced into a physical trainer with multiple ports to carry out fully endoscopic microsurgical procedures. The vertical and horizontal dimensions of the paired ports (simulated nostrils) were: 35×20 mm, 35×15 mm, 25×15 mm, and 25×10 mm. 2 additional single 11.5 mm endoscopic ports were added. Surgical depth varied as desired between 8 and 15 cm. The cervical and abdominal regions were the focus of the endoscopic microsurgical exercises. RESULTS: The different endoscopic neurosurgical techniques were effectively trained at the millimetric dimension. Levels of progressive surgical difficulty depending upon the endoneurosurgical skills set needed for a particular surgical exercise were distinguished. LEVEL 1 is soft-tissue microdissection (exposure of cervical muscular plane and retroperitoneal space); LEVEL 2 is soft-tissue-vascular and vascular-capsule microdissection (aorto-cava exposure, carotid sheath opening, external jugular vein isolation); LEVEL 3 is artery-nerve microdissection (carotid-vagal separation); LEVEL 4 is artery-vein microdissection (aorto-cava separation); LEVEL 5 is vascular repair and microsuturing (aortic rupture), which verified the lack of current proper instrumentation. CONCLUSION: The animal training model presented here has the potential to shorten the length of the learning curve in endonasal endoscopic and neuroendoscopic port surgery and reduce the incidence of training-related surgical complications.

Endoscopic, endonasal decompression of spinal stenosis with myelopathy secondary to cranio-vertebral tuberculosis: two cases.

BACKGROUND: Tuberculosis can cause extensive osseo-ligamentous destruction at the cranio-vertebral junction, leading to atlanto-axial instability and compression of vital cervico-medullary centres. This may manifest as quadriparesis, bulbar dysfunction and respiratory insufficiency. AIM: We report two patients presenting with spinal stenosis and cord compression secondary to cranio-vertebral tuberculosis, who were successfully decompressed via an endoscopic, endonasal approach. STUDY DESIGN: Two case reports. METHODS AND RESULTS: Both patients were successfully decompressed via an endoscopic, endonasal approach which provided access to the cranio-vertebral junction and upper cervical spine. CONCLUSION: An endoscopic, endonasal approach is feasible for the surgical management of cranio-vertebral junction stenosis; such an approach minimises surgical trauma to critical structures, reducing post-operative morbidity and the duration of hospital stay.

Hypoxia promotes expansion of the CD133-positive glioma stem cells through activation of HIF-1alpha.

Hypoxia contributes to the progression of a variety of cancers by activating adaptive transcriptional programs that promote cell survival, motility and tumor angiogenesis. Although the importance of hypoxia and subsequent hypoxia-inducible factor-1alpha (HIF-1alpha) activation in tumor angiogenesis is well known, their role in the regulation of glioma-derived stem cells is unclear. In this study, we show that hypoxia (1% oxygen) promotes the self-renewal capacity of CD133-positive human glioma-derived cancer stem cells (CSCs). Propagation of the glioma-derived CSCs in a hypoxic environment also led to the expansion of cells bearing CXCR4 (CD184), CD44(low) and A2B5 surface markers. The enhanced self-renewal activity of the CD133-positive CSCs in hypoxia was preceded by upregulation of HIF-1alpha. Knockdown of HIF-1alpha abrogated the hypoxia-mediated CD133-positive CSC expansion. Inhibition of the phosphatidylinositol 3-kinase(PI3K)-Akt or ERK1/2 pathway reduced the hypoxia-driven CD133 expansion, suggesting that these signaling cascades may modulate the hypoxic response. Finally, CSCs propagated at hypoxia robustly retained the undifferentiated phenotype, whereas CSCs cultured at normoxia did not. These results suggest that response to hypoxia by CSCs involves the activation of HIF-1alpha to enhance the self-renewal activity of CD133-positive cells and to inhibit the induction of CSC differentiation. This study illustrates the importance of the tumor microenvironment in determining cellular behavior.

The MR imaging appearance of the vascular pedicle nasoseptal flap.

BACKGROUND AND PURPOSE: Recently, surgeons have used an expanded endonasal surgical approach (EENS) to access skull base lesions not previously accessible by minimally invasive techniques. Reconstruction of the large skull base defects created during EENS is necessary to prevent postoperative CSF leaks. A vascular pedicle nasoseptal mucoperiosteal flap based on the nasoseptal artery, (Hadad-Bassagasteguy flap) is becoming a common reconstructive technique. The purpose of this study was to review the expected MR imaging appearance of these flaps and to discuss variations in the appearance that may suggest potential flap failure. MATERIALS AND METHODS: We retrospectively reviewed 10 patients who underwent EENS for resection of sellar lesions with skull base reconstruction by multilayered reconstruction including the Hadad-Bassagasteguy flap. All patients had preoperative, immediate, and delayed postoperative MR imaging scans. Flap features that were evaluated included flap configuration, signal intensity characteristics on T1-weighted and T2-weighted images, enhancement patterns, location, and flap thickness. RESULTS: All patients had detectable postoperative skull base defects. All patients had C-shaped configuration flaps within the operative defect, which were isointense on T1-weighted and T2-weighted images on both immediate and delayed postoperative MR imaging scans. On the immediate scans, 8 of 10 patients had enhancing flaps and 2 of 10 had minimal to no enhancement. There were 9 of 10 patients who had enhancing flaps on delayed scans, and 2 of 10 patients had flaps that increased in enhancing coverage on the delayed scans. CONCLUSIONS: Vascular pedicle nasoseptal flaps have a characteristic MR imaging appearance. It is important for the radiologist to recognize this appearance and to evaluate for variations that may suggest potential flap failure.

The antero-medial triangle: the risk for cranial nerves ischemia at the cavernous sinus lateral wall. Anatomic cadaveric study.

OBJECTIVE: Vascular damage in the cavernous sinus can cause ischemic injury to the cranial nerves. An appropriate anatomical knowledge of the blood supply to the cranial nerves can help to reduce the morbidity associated with cavernous sinus surgery. MATERIAL AND METHODS: Three formalin-fixed and six adult cadaveric fresh heads, with common carotid arteries injected, were used for anatomical dissection in this study. A fronto-temporal craniotomy was performed and the cavernous sinus was explored according to the Dolenc technique. With microsurgical dissection and photographic documentation, we demonstrate the anatomy of the superior orbital fissure artery in the antero-medial triangle. RESULTS: The 12 explored cavernous sinuses demonstrated the presence of two principal branches directly from the intracavernous internal carotid artery that supply the cranial nerves: the infero-lateral trunk and the meningohypophyseal trunk. The artery of the Superior Orbital Fissure (SOF), originated more often from the infero-lateral trunk, and vascularized the III, IV, VI, and VI, and ophtalmic division of the trigeminal nerve (TGN VI) at their entry in the fissure. CONCLUSION: In this study we demonstrate that the superior orbital fissure artery is a branch from the infero-lateral trunk which runs immediately under the reticularis layer at the level of the anteromedial triangle in the lateral wall of the cavernous sinus. The blood supply to all cranial nerves in the SOF is at risk to injury when the lateral wall of the cavernous sinus is transgressed at the anteromedial triangle since the SOF-artery runs superficially at this level.

Anatomic results and complications of stent-assisted coil embolization of intracranial aneurysms.

SUMMARY: The purpose of this study was to evaluate and report our anatomic results and complications associated with stent-assisted coil embolization of intracranial aneurysms using the Neuroform stent. From September 2003 to August 2007, 127 consecutive patients (ruptured 50, 39.4%; unruptured 77, 60.6%) underwent 129 stent-assisted coil embolization procedures to treat 136 aneurysms at our institution. Anatomic results at follow-up, procedure-related complications, and morbidity/mortality were retrospectively reviewed. Stent deployment was successful in 128 out of 129 procedures (99.2%). Forty-seven patients presented with 53 procedure-related complications (37.0%, 47/127). Thromboembolic events (n=17, 13.4%) were the most common complications, followed by intraoperative rupture (n=8, 6.3%), coil herniation (n=5, 3.9%), and postoperative rupture (n=4, 3.1%). For thromboembolic events, acute intra-procedural instent thromboses were observed in two patients and subacute or delayed in-stent thromboses in three patients. Overall mortality rate was 16.5% (21/127) and procedure-related morbidity and mortality rates were 5.5% (7/127) and 8.7% (11/127) retrospectively. Patients with poor grade subarachnoid hemorrhage (Hunt and Hess grade IV or V; 25/127, 19.7%) exhibited 56% (14/25) overall mortality rate and 24% (6/25) procedure-related mortality rate. Immediate angiographic results showed complete occlusion in 31.7% of aneurysms, near-complete occlusion in 45.5%, and partial occlusion in 22.8%. Sixty nine patients in 70 procedures with 77 aneurysms underwent angiographic followup at six months or later. Mean follow-up period was 13.7 months (6 to 45 months). Complete occlusion was observed in 57 aneurysms (74.0%) and significant in-stent stenosis was not found. Thromboembolism and intra/postoperative aneurysm ruptures were the most common complications and the main causes of procedure-related morbidity and mortality. Patients with poor grade subarachnoid hemorrhage showed poor clinical outcomes. Since most complications were induced by stent manipulation and deployment, it is mandatory to utilize these devices selectively and cautiously. While the follow- up angiographic results are promising, further studies are essential to evaluate safety, efficacy, and durability of the Neuroform stent.

Risk of hemorrhage in combined neuroform stenting and coil embolization of acutely ruptured intracranial aneurysms.

SUMMARY: Stenting as adjuvant therapy for the coiling of acutely ruptured aneurysms remains controversial due to the necessity of anticoagulation and antiplatelet medications. We report our experience using the Neuroform stent in the management of 41 aneurysms in 40 patients over a period of three years. For aneurysms whose open surgical risk remains excessive with a morphology that would preclude complete embolization, the risks of stenting may be warranted.

Stenting and angioplasty of the symptomatic chronically occluded carotid artery.

Patients with hemodynamic impairment ipsilateral to a carotid occlusion are at a high risk of subsequent stroke, and currently 2 surgical options have been studied: extracranial-to-intracranial bypass and direct thromboendarterectomy. We report the successful revascularization of 2 symptomatic chronically occluded carotid arteries with stenting and angioplasty.