Pak Yin Lam

BACKGROUND AND OBJECTIVES: Bone flap infection and contamination are feared complications of cranial surgery, yet optimal management remains controversial. The aim of this review was to determine comparative outcomes of preservation with decontamination and reinsertion vs discard and replacement after intraoperatively contaminated or postoperatively infected bone flaps. METHODS: We systematically reviewed 70 studies (621 patients) reporting either intraoperatively contaminated or postoperatively infected flaps (PROSPERO: CRD420251041697). Patient demographics, decontamination protocols, replacement materials, and outcomes were extracted and synthesized. RESULTS: Three studies (49 patients) reported intraoperative contamination from dropped flaps, whereas 67 studies (572 patients) reported postoperative flap infections. Decontamination methods involved washing, scrubbing, and soaking with saline, povidone-iodine, peroxide or an antibiotic/antiseptic agent, and/or autoclaving, while replacement materials included titanium, polymethyl methacrylate, polyether ether ketone, or hydroxyapatite. Most patients achieved satisfactory cosmetic and neurological outcomes, with comparably low complication rates. None of the intraoperatively contaminated flaps developed postoperative infections after either approach. Preserved flaps carried significantly higher reoperation risk (absolute risk ratio 6.68%, odds ratio 2.948, 95% CI 1.450-5.993, P = .006). This means for every 15 patients treated with decontamination rather than replacement, one extra reoperation occurs. All reoperations occurred in patients with postoperatively infected flaps, most commonly because of severe recurrent infection. Comorbidities, for example, radiotherapy, immunosuppression, diabetes, and high body mass index, also emerged as a significant predictor of reoperation risk in logistic regression analysis (adjusted odds ratio 44.2, 95% CI 1.17-436, P = .0012). CONCLUSION: This is the largest pooled individual-patient data synthesis to date on management of contaminated or infected bone flaps. Both decontamination and replacement provide good outcomes and are safe and effective for intraoperatively contaminated flaps. However, decontamination with reinsertion carries higher reoperation risk compared with flap replacement among patients with postoperatively infected flaps. Flap preservation should therefore be undertaken selectively considering organism virulence, presence of purulence, and comorbidities. These results inform development of standardized risk-stratified guidelines and cost-effectiveness evaluation for bone flap management in cranial surgery.

Myocardial infarction (MI) is a leading cause of mortality, affecting 3.8% of the global population under 60 years of age, and 9.5% over 60 years. Adverse post-MI remodelling is the main contributor to heart failure, conferring a three- to six-fold increase in risk of premature death. Current imaging modalities, such as nuclear imaging and magnetic resonance imaging, provide structural and functional information of the heart and identify extracellular expansion for indirect estimation of infarct size. However, they do not characterize the exact biological mechanisms involved, nor the staging of disease progression. Molecular imaging aims to visualize the underlying processes of remodelling at a molecular and cellular level, aiding more accurate prognosis and targeted treatment. Molecular tracers, such as radioisotopes and paramagnetic nanoparticles, are modified to adhere to specific molecules or cells involved in inflammation, angiogenesis, and scar formation, which can be visualized and quantitatively assessed using positron-emission tomography and magnetic resonance imaging. This article provides an overview of the pathophysiology of adverse remodelling, the latest molecular contrast agents under development, and future directions for integration into clinical practice.

Spatial skills, or spatial ability, is the ability to visualize and mentally manipulate three‐dimensional objects, and is essential to the study of anatomy. This study aims to investigate whether spatial skills required to infer cross‐sectional images could be improved through anatomy learning, as well as gender differences in spatial skills. First‐year medical students from 2016, 2018, and 2019 at King's College London undertook two online tests examining their ability to identify cross‐sections of various anatomical structures and geometric solids from the Santa Barbara Solids Test (SBST). Test 1 took place in October before anatomy teaching, and Test 2 in December after anatomy teaching on the abdomen and pelvis. Mean scores were compared between Test 1 and Test 2 using the paired t‐test, and between male and female students using the chi‐squared test. Results demonstrate a trend toward improved performance in anatomical questions following anatomy teaching, although the extent of improvement was not consistent across cohorts. This trend remained evident even after exclusion of questions on the abdomen and pelvis. However, mean scores for SBST questions decreased significantly. No significant difference in spatial performance was observed between males and females. Our results suggest that spatial reasoning of anatomical cross‐sections could potentially be improved through anatomy teaching. Furthermore, improvements in spatial ability may be transferrable across body systems through the development and activation of mental schemas. However, they may not be transferrable to the broader domain of geometric solids, necessitating further research.

Background: Neurosurgery for mental disorder (NMD), colloquially known as ‘psychosurgery’, a branch of neurosurgery defined by the World Health Organization (WHO) as the selective surgical removal or destruction of neural pathways to influence behaviour, has evolved significantly since its inception in the 1930s. NMD has a profound yet controversial history, from Antonio Egaz Moniz, founder and pioneer of the prefrontal leucotomy and cerebral angiography. Globally, the acceptance and applications of NMD vary significantly: in some regions, it is a well-established part of the therapeutic arsenal, while in others it remains controversial or underutilized. Yet, research on modern applications of NMD remains limited, indicated in a range of psychiatric disorders in cases where conservative or pharmacological treatments have been deemed intractable. These comprise treatment-resistant depression, anxiety, anorexia nervosa, obsessive-compulsive disorder, bipolar disorder, schizophrenia, and Tourette's syndrome. Historically, NMD stipulated lobotomies where corticectomy was practiced. Now, deep brain and vagus nerve stimulation, gamma knife radiosurgery, stereotactic radiosurgery, and focused ultrasound have revolutionised NMD. Hence, this systematic review aims to comprehensively evaluate the current psychosurgery landscape from 2000 onwards, comparing patient demographics, functional outcomes, complication and mortality rates between different types of psychosurgeries. Methods: A systematic review and meta-analysis will be performed between 2000 to 2024, adhering to the PRISMA-P guidelines alongside the Cochrane Handbook of Systematic Reviews of Interventions. Search databases used were PubMed/MEDLINE, EMBASE, GlobalHealth, APA PsycInfo, and Scopus. Search terms, alongside Boolean operators, were employed, examining mental health conditions eligible for NMD and procedures indicated. We will also review the reference sections of each eligible article. Inclusion criteria for this review include studies written in the medium of the English language involving neurosurgery for psychiatric disorders between 2000 to 2024. Studies were only considered eligible to be included if they had complete individual patient data. Two independent reviewers will screen the abstracts and titles. A third, impartial reviewer will settle any disputes. Discussion: The evidence basis pertaining to this review will cohere to the thorough evaluation of NMD across contrasting patient demographics, functional outcomes, postoperative sequalae, comorbidity and mortality rates in modern-day neurosurgical practice. Systemic Review Registration: PROSPERO 2024 CRD42024610729. Future amendments to the protocol will be updated on the PROSPERO record.

With the advent of healthcare globalization, interprofessional collaboration has become increasingly important on an international scale. This longitudinal study evaluated group dynamics in the International Collaboration and Exchange Program, a global online program of students across 33 universities from diverse healthcare backgrounds, including medicine, dentistry, pharmacy, and biomedical science. In groups of 4 to 6, participants engaged in regular discussions and projects relating to anatomy education and global health. Peer assessment was used to determine (1) whether a relationship existed between group cohesiveness and disparities in individual contribution levels and (2) whether group cohesiveness and individual contribution levels changed over time across varying group sizes. Two student cohorts were studied using the Individual Peer Assessment of Contribution methodology. Peer assessment surveys were distributed at two time points for the first (2021–2022) and second (2022–2023) cohorts, respectively, yielding 423 responses from 126 groups. Collaboration quality and effectiveness were evaluated through numerical ratings and qualitative feedback. Peer assessment is a viable tool for evaluating the dynamics of group interactions in virtual collaboration on a global scale. A reduction in group cohesiveness was associated with greater imbalances in individual contribution levels (r = −0.71, p < 0.001). Furthermore, larger groups (n = 6 students) demonstrated improved cohesiveness and equality in individual contribution levels over time compared to smaller groups (n = 4 students). This study on international healthcare student collaboration provides insights into sociocultural and educational factors impacting virtual group interactions and offers strategies for enhancing interprofessional collaborative practices in global health education.

Background/Objectives: Intradural extramedullary (IDEM) spinal tumours are relatively rare and predominantly benign. Gross total resection (GTR) has been demonstrated as an effective treatment, with increasing evidence supporting the use of minimally invasive techniques to achieve GTR. This study reviews the current surgical management options for IDEM tumours and their outcomes. Methods: A systematic literature search without meta-analysis was conducted by two independent reviewers in December 2024. The population of interest comprised patients who underwent surgical treatment for IDEM tumours. Outcomes assessed included the extent of resection, postoperative neurological function, and complications. Results: Fifty-seven articles met the inclusion criteria, providing data on 4695 IDEM cases, of which 3495 were managed through open surgery and 750 via minimally invasive surgery. The extent of resection was high, with a mean GTR > 90% across studies. Open laminectomy and unilateral minimally invasive hemilaminectomy were the most common surgical approaches. Complications, such as cerebrospinal fluid leaks, were less frequent following minimally invasive procedures vs. open surgery (11.1% vs. 14.3%). Minimally invasive surgery also led to improved postoperative functional outcomes (mean McCormick score change −1.30 vs. −0.64) and a lower recurrence rate (1.4% vs. 10.0%). Conclusions: Whilst open surgery yields acceptable rates of resection and neurological improvement, there is growing evidence that minimally invasive surgery can achieve comparable, if not superior, rates of resection with fewer complications, leading to lower costs and shorter hospital stays.