Design and Application of Intelligent Reflecting Surface (IRS) for Beyond 5G Wireless Networks: A Review.

The existing sub-6 GHz band is insufficient to support the bandwidth requirement of emerging data-rate-hungry applications and Internet of Things devices, requiring ultrareliable low latency communication (URLLC), thus making the migration to millimeter-wave (mmWave) bands inevitable. A notable disadvantage of a mmWave band is the significant losses suffered at higher frequencies that may not be overcome by novel optimization algorithms at the transmitter and receiver and thus result in a performance degradation. To address this, Intelligent Reflecting Surface (IRS) is a new technology capable of transforming the wireless channel from a highly probabilistic to a highly deterministic channel and as a result, overcome the significant losses experienced in the mmWave band. This paper aims to survey the design and applications of an IRS, a 2-dimensional (2D) passive metasurface with the ability to control the wireless propagation channel and thus achieve better spectral efficiency (SE) and energy efficiency (EE) to aid the fifth and beyond generation to deliver the required data rate to support current and emerging technologies. It is imperative that the future wireless technology evolves toward an intelligent software paradigm, and the IRS is expected to be a key enabler in achieving this task. This work provides a detailed survey of the IRS technology, limitations in the current research, and the related research opportunities and possible solutions.

A Survey of Autonomous Vehicles: Enabling Communication Technologies and Challenges.

The Department of Transport in the United Kingdom recorded 25,080 motor vehicle fatalities in 2019. This situation stresses the need for an intelligent transport system (ITS) that improves road safety and security by avoiding human errors with the use of autonomous vehicles (AVs). Therefore, this survey discusses the current development of two main components of an ITS: (1) gathering of AVs surrounding data using sensors; and (2) enabling vehicular communication technologies. First, the paper discusses various sensors and their role in AVs. Then, various communication technologies for AVs to facilitate vehicle to everything (V2X) communication are discussed. Based on the transmission range, these technologies are grouped into three main categories: long-range, medium-range and short-range. The short-range group presents the development of Bluetooth, ZigBee and ultra-wide band communication for AVs. The medium-range examines the properties of dedicated short-range communications (DSRC). Finally, the long-range group presents the cellular-vehicle to everything (C-V2X) and 5G-new radio (5G-NR). An important characteristic which differentiates each category and its suitable application is latency. This research presents a comprehensive study of AV technologies and identifies the main advantages, disadvantages, and challenges.

Device Free Detection in Impulse Radio Ultrawide Bandwidth Systems.

In this paper, an analytical framework is presented for device detection in an impulse radio (IR) ultra-wide bandwidth (UWB) system and its performance analysis is carried out. The Neyman-Pearson (NP) criteria is employed for this device-free detection. Different from the frequency-based approaches, the proposed detection method utilizes time domain concepts. The characteristic function (CF) is utilized to measure the moments of the presence and absence of the device. Furthermore, this method is easily extendable to existing device-free and device-based techniques. This method can also be applied to different pulse-based UWB systems which use different modulation schemes compared to IR-UWB. In addition, the proposed method does not require training to measure or calibrate the system operating parameters. From the simulation results, it is observed that an optimal threshold can be chosen to improve the ROC for UWB system. It is shown that the probability of false alarm, PFA, has an inverse relationship with the detection threshold and frame length. Particularly, to maintain PFA<10-5 for a frame length of 300 ns, it is required that the threshold should be greater than 2.2. It is also shown that for a fix PFA, the probability of detection PD increases with an increase in interference-to-noise ratio (INR). Furthermore, PD approaches 1 for INR >-2 dB even for a very low PFA i.e., PFA=1×10-7. It is also shown that a 2 times increase in the interference energy results in a 3 dB improvement in INR for a fixed PFA=0.1 and PD=0.5. Finally, the derived performance expressions are corroborated through simulation.

Partial vs radical nephrectomy for T1 renal tumours: an analysis from the British Association of Urological Surgeons Nephrectomy Audit.

OBJECTIVES: To analyse and compare data from the British Association of Urological Surgeons Nephrectomy Audit for perioperative outcomes of partial (PN) and radical nephrectomy (RN) for T1 renal tumours. PATIENTS AND METHODS: UK consultants were invited to submit data on all patients undergoing nephrectomy between 1 January and 31 December 2012 to a nationally established database using a standard pro forma. Analysis was made on patient demographics, operative technique, and perioperative data/outcome between PN and RN for T1 tumours. RESULTS: Overall, data from 6 042 nephrectomies were reported of which 1 768 were performed for T1 renal tumours. Of these, 1 082 (61.2%) were RNs and 686 (38.8%) were PNs. The mean age of patients undergoing PN was lower (PN 59 years vs RN 64 years; P < 0.001) and so was the WHO performance score (PN 0.4 vs RN 0.7; P < 0.001). PN for the treatment of T1a tumours (≤4 cm) accounted for 55.6% of procedures, of which 43.9% were performed using a minimally invasive technique. For T1b tumours (4-7 cm), 18.9% of patients underwent PN, in 33.3% of which a minimally invasive technique was adopted. The vast majority of RNs for T1 tumours were performed using a minimally invasive technique (90.3%). Of the laparoscopic PNs, 30.5% were robot-assisted. There was no significant difference in overall intraoperative complications between the RN and PN groups (4% vs 4.3%; P = 0.79). However, PN accounted for a higher overall postoperative complications rate (RN 11.3% vs PN 17.6%; P < 0.001). RN was associated with a markedly reduced risk of severe surgical complications (Clavien Dindo classification grade ≥3) compared with PN even after adjusting for technique (odds ratio 0.30; P = 0.002). Operation time between RN and PN was comparable (141 vs 145 min; P = 0.25). Blood loss was less in the RN group (mean for RN 165 vs PN 323 mL; P < 0.001); however, transfusion rates were similar (3.2% vs 2.6%; P = 0.47). RN was associated with a shorter length of stay (median 4 vs 5 days; P < 0.001). A direct comparison between robot-assisted and laparoscopic PN showed no significant differences in operation time, blood loss, warm ischaemia time, and intraoperative and postoperative complications. CONCLUSIONS: PN was the method of choice for treatment of T1a tumours whereas RN was preferred for T1b tumours. Minimally invasive techniques have been widely adopted for RN but not for PN. Despite the advances in surgical technique, a substantial risk of postoperative complications remains with PN.

Human prion diseases: surgical lessons learned from iatrogenic prion transmission.

The human prion diseases, or transmissible spongiform encephalopathies, have captivated our imaginations since their discovery in the Fore linguistic group in Papua New Guinea in the 1950s. The mysterious and poorly understood "infectious protein" has become somewhat of a household name in many regions across the globe. From bovine spongiform encephalopathy (BSE), commonly identified as mad cow disease, to endocannibalism, media outlets have capitalized on these devastatingly fatal neurological conditions. Interestingly, since their discovery, there have been more than 492 incidents of iatrogenic transmission of prion diseases, largely resulting from prion-contaminated growth hormone and dura mater grafts. Although fewer than 9 cases of probable iatrogenic neurosurgical cases of Creutzfeldt-Jakob disease (CJD) have been reported worldwide, the likelihood of some missed cases and the potential for prion transmission by neurosurgery create considerable concern. Laboratory studies indicate that standard decontamination and sterilization procedures may be insufficient to completely remove infectivity from prion-contaminated instruments. In this unfortunate event, the instruments may transmit the prion disease to others. Much caution therefore should be taken in the absence of strong evidence against the presence of a prion disease in a neurosurgical patient. While the Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) have devised risk assessment and decontamination protocols for the prevention of iatrogenic transmission of the prion diseases, incidents of possible exposure to prions have unfortunately occurred in the United States. In this article, the authors outline the historical discoveries that led from kuru to the identification and isolation of the pathological prion proteins in addition to providing a brief description of human prion diseases and iatrogenic forms of CJD, a brief history of prion disease nosocomial transmission, and a summary of the CDC and WHO guidelines for prevention of prion disease transmission and decontamination of prion-contaminated neurosurgical instruments.

Neurophysiological Monitoring During Spinal Cord Stimulator Placement Surgery.

OBJECTIVES: The objective of this retrospective study was to study the frequency of intraoperative neuromonitoring (IONM) alerts during the spinal cord stimulator (SCS) placement surgery, postoperative neurological complications and effectiveness of Somatosensory evoked potential (SSEP) and electromyography (EMG) methods to determine laterality of the SCS lead placement. MATERIALS AND METHODS: Records of 111 consecutive SCS placement surgeries monitored by a commercial IONM company between August 1, 2013 and December 31, 2013 were reviewed. IONM alerts, surgical interventions, and patient outcomes were assessed. RESULTS: Significant decreases of lower extremity SSEPs following the placement of the SCS paddle electrodes into the epidural space were recorded in two (1.9%) patients prompting alerts to the surgeons and removal of the electrode. Somatosensory system dysfunction due to stimulated limb malpositioning was identified by continuous SSEP in four cases (3.8%). All waveform changes resolved and SSEP waveforms returned back to baselines in all six patients after adjustments were made. There was no evidence of sustained neurological injury in any patients in this study. The location of the stimulator was adjusted based on IONM feedback in 8/43 (18.6%) cases. CONCLUSIONS: IONM is an effective tool in detecting potential neurological event and facilitating lead placement and potentially avoiding revision surgery.

Elucidating the performance of hexamethylene tetra-amine interlinked bimetallic NiCo-MOF for efficient electrochemical hydrogen and oxygen evolution.

Bimetallic metal-organic frameworks (MOFs) play a significant role in the electrocatalysis of water due to their large surface area and availability of increased numbers of pores. For the inaugural time, we examine the effectiveness of a hexamethylene tetra-amine (HMT)-induced 3D NiCo-MOF-based nanostructure as a potent bifunctional electrocatalyst with superior performance for overall water splitting in alkaline environments. The structural, morphological, and electrochemical properties of the as-synthesized bifunctional catalyst were examined thoroughly before analyzing its behavior towards electrochemical water splitting. The HMT-based NiCo-MOF demonstrated small overpotential values of 274 mV and 330 mV in reaching a maximum current density of 30 mA cm-2 for hydrogen and oxygen evolution mechanisms, respectively. The Tafel parameter also showed favorable HER/OER reaction kinetics, with slopes of 78 mV dec-1 and 86 mV dec-1 determined during the electrochemical evaluation. Remarkably, the NiCo-HMT electrode exhibited a double-layer capacitance of 4 mF cm-2 for hydrogen evolution and 23 mF cm-2 for oxygen evolution, while maintaining remarkable stability even after continuous operation for 20 hours. This research offers a valuable blueprint for implementing a cost-effective and durable MOF-based bifunctional catalytic system that has proven to be effective for complete water splitting. Decomposition of water under higher current densities is crucial for effective long-term generation and commercial consumption of hydrogen.

Fournier's gangrene associated with intradermal injection of cocaine.

INTRODUCTION: Cocaine abuse is associated with a number of medical complications, most notably arrhythmias, myocardial infarction, and cerebral hemorrhages. The injection of cocaine in the penis has been predominantly recorded into the corpus cavernosae and is associated with priapism. AIM: Here we describe the injection of subcutaneous cocaine within the penile shaft skin producing ischemic necrosis and Fournier's gangrene. MAIN OUTCOME MEASURES: We sought to highlight the effects of cocaine use within the penis and emphasize the different effects that may ensue. METHODS: We reviewed a recent clinical case and conducted a literature review on the use of cocaine within the penis. RESULTS: The use of cocaine has been reported previously within the literature and is mainly limited to case reports. Cocaine use within the corpora and the subcutaneous tissues produces significantly different consequences ranging from priapism to Fournier's gangrene. CONCLUSIONS: The case illustrates the growing use of cocaine and other illicit drugs and emphasizes the importance of this issue to all clinicians.

The story of the condom.

Condoms have been a subject of curiosity throughout history. The idea of safer sex has been explored in ancient and modern history, and has been used to prevent venereal diseases. We conducted a historical and medical review of condoms using primary and secondary sources as well as using the RSM library and the internet. These resources show that the first use of a condom was that of King Minos of Crete. Pasiphae, his wife, employed a goat's bladder in the vagina so that King Minos would not be able to harm her as his semen was said to contain "scorpions and serpents" that killed his mistresses. To Egyptians, condom-like glans caps were dyed in different colours to distinguish between different classes of people and to protect themselves against bilharzia. The Ancient Romans used the bladders of animals to protect the woman; they were worn not to prevent pregnancy but to prevent contraction of venereal diseases. Charles Goodyear, the inventor, utilized vulcanization, the process of transforming rubber into malleable structures, to produce latex condoms. The greater use of condoms all over the world in the 20(th) and 21(st) centuries has been related to HIV. This account of the use of condoms demonstrates how a primitive idea turned into an object that is used globally with a forecast estimated at 18 billion condoms to be used in 2015 alone.

Neurotrophic Keratopathy and Topical Insulin Therapy: A Case Report.

Neurotrophic keratopathy is a rare disorder caused by the loss of corneal sensation. It is characterized by persistent epithelial defects, corneal ulceration, and, ultimately, corneal perforation if not managed in a timely manner. The management includes aggressive lubrication, prophylactic topical antibiotics, therapeutic contact lenses, tarsorrhaphy, and amniotic membrane transplantation. Some novel therapeutic options are also available, one of which is topical insulin therapy. We report the clinical course of a patient with neurotrophic keratopathy that was successfully treated with topical insulin. A 64-year-old male presented to our outpatient department with a three-month history of painless blurring of vision following prior episodes of herpetic keratitis. Ocular examination showed a bilateral reduction in corneal sensations, bilateral corneal opacities, and a corneal ulcer in the left eye. He was diagnosed as a case of neurotrophic keratopathy secondary to prior herpetic keratitis. He was then treated with topical and oral acyclovir along with topical insulin drops. There was a remarkable improvement in his condition after a month with a reduction in the size of the ulcer and, after two months, the ulcer was completely re-epithelialized. This case report illustrates the use of topical insulin in the initial management of neurotrophic keratopathy as opposed to its conventional use in refractory neurotrophic corneal ulcers.

Long COVID-19 Syndrome: Insights From a Major Tertiary Center in the UK on Who Is at Greater Risk.

INTRODUCTION: The COVID-19 pandemic triggered the unprecedented 'long COVID' crisis, with persistent symptoms beyond two months post-infection. This study explores the nexus between long COVID symptoms, patient demographics such as age, gender, and smoking, and clinical factors like vaccination, disease severity, and comorbidities. METHODS: A retrospective analysis of records was conducted between September 2021 and December 2022. The analysis covered adults with confirmed COVID-19 diagnoses. Data encompassed demographics, medical history, vaccination, disease severity, hospitalization, treatments, and post-COVID symptoms, analyzed using logistic regression. RESULTS: Among 289 participants, the average age was 51.51 years. Around 62.6% were females, and 93% received the COVID-19 vaccination, i.e., primarily the mRNA vaccine (48.4%) and the adenovirus vector-based vaccine (34.8%). Reinfections occurred in 11.76% of cases. Disease severity varied, with 75% having mild, 15% having moderate, and 10% having severe infections. Hospitalization rates were significant (25.6%), including 10.7% requiring intensive care. Thirteen distinct post-COVID symptoms were reported. Fatigue, shortness of breath upon exertion, and brain fog emerged as the most prevalent symptoms. Notably, females exhibited higher symptom prevalence. Significant correlations were established between higher BMI and smoking with augmented symptomatology. Conversely, a link between booster doses and symptom reduction was discerned. Using multinomial regression analysis, gender and smoking were identified as predictors of post-COVID-19 symptoms. CONCLUSION: The study underscores obesity, smoking, and the female gender's impact on long COVID symptoms; boosters show promise in alleviation. Respiratory pathology might underlie persistent symptoms in cases with radiological abnormalities and abnormal spirometry. Findings contribute to risk stratification, intervention strategies, and further research.

Raised Glycated Hemoglobin (HbA1c) Level as a Risk Factor for Myocardial Infarction in Diabetic Patients: A Hospital-Based, Cross-Sectional Study in Peshawar.

Background Diabetes is a rapidly rising chronic illness in developing countries. The main objective of this research is to compare the frequency of myocardial infarction (MI) in controlled and uncontrolled diabetics in Pakistan, especially in the underprivileged district of Peshawar, and to determine raised blood glucose as a risk factor for MI. Methodology This cross-sectional study involving 237 diabetic patients aged 30-80 years was conducted in three major tertiary care hospitals in Peshawar, Pakistan. The inclusion criteria were diabetic patients with glycated hemoglobin (HbA1C) levels of less than 7% considered to be "controlled diabetics" and above 7% considered to be "uncontrolled diabetics." Data were collected using structured questionnaires, past medical records, and patient history and were analyzed using SPSS software (IBM Corp., Armonk, NY, USA). The study was concluded in March 2022. Results The highest number of MIs occurred in diabetics with HbA1c levels of 8-9% (47.9% of all MIs). There was a significant association between increasing HbA1c levels and the incidence of MI (p = 0.002). The adjusted prevalence odds ratio for MI in uncontrolled diabetics was 6.105 (95% confidence interval = 2.42-15.43), that is, six times increased incidence of MI in patients with HbA1c of more than 7%. Furthermore, with a 1% increase in HbA1c, there was a 10% increase in the proportion of MIs. Conclusions From this study, it is clear that HbA1c levels of 8-9% were most significantly associated with the risk of MI in uncontrolled diabetics, and with rising levels of HbA1c, the risk of MI increased significantly. Thus, this study highlights the importance of HbA1c control in diabetic patients to prevent a heart attack.

Pharmacological management of acromegaly: a current perspective.

Acromegaly is a chronic disorder of enhanced growth hormone (GH) secretion and elevated insulin-like growth factor­I (IGF-I) levels, the most frequent cause of which is a pituitary adenoma. Persistently elevated GH and IGF-I levels lead to substantial morbidity and mortality. Treatment goals include complete removal of the tumor causing the disease, symptomatic relief, reduction of multisystem complications, and control of local mass effect. While transsphenoidal tumor resection is considered first-line treatment of patients in whom a surgical cure can be expected, pharmacological therapy is playing an increased role in the armamentarium against acromegaly in patients unsuitable for or refusing surgery, after failure of surgical treatment (inadequate resection, cavernous sinus invasion, or transcapsular intraarachnoid invasion), or in select cases as primary treatment. Three broad drug classes are available for the treatment of acromegaly: somatostatin analogs, dopamine agonists, and GH receptor antagonists. Somatostatin analogs are considered as the first-line pharmacological treatment of acromegaly, although efficacy varies among the different formulations. Octreotide long-acting release (LAR) appears to be more efficacious than lanreotide sustained release (SR). Lanreotide Autogel (ATG) has been shown to result in similar biological control as octreotide LAR, and there may be a benefit in switching from one to the other in some cases of treatment failure. The novel multireceptor somatostatin analog pasireotide, currently in Phase II clinical trials, also shows promise in the treatment of acromegaly. Dopamine agonists have been the earliest and most widely used agents in the treatment of acromegaly but have been found to be less effective than somatostatin analogs. In this class of drugs, cabergoline has shown greater efficacy and tolerability than bromocriptine. Dopamine agonists have the advantage of oral administration, resulting in increased use in select patient groups. Selective GH receptor antagonists, such as pegvisomant, act by blocking the effects of GH, resulting in decreased IGF-I production despite persistent elevation of GH serum levels. Thus far, tumor growth has not been a concern during pegvisomant therapy. However, combination treatment with somatostatin analogs may counteract these effects. The authors discuss the latest guidelines for biochemical cure and highlight the efficacy of combination therapy. In addition, the effects of pharmacological presurgical treatment on surgical outcome are explored.

Thyroid Storm, a Mimicker of Guillain-Barre Syndrome: A Case Report.

A 60-year-old woman with diabetes mellitus presented to the emergency department (ER) with complaints of lower limb weakness, preceded by diarrhea. She complained of sweating and palpitations. There was no fever, cough, trauma, seizures, or headache. There was global weakness in all four limbs with absent reflexes and hypotonia. Examination of cranial nerves, the sensory system, and other systems was normal. Guillain-Barre syndrome (GBS) was suspected, but due to the patient's co-morbidities, treatment was withheld for 24 hours and the patient was kept under observation. Medical consultation was sought and thyroid function tests were ordered which showed thyroid-stimulating hormone (TSH) 0.019 uIU/ml (normal: 0.35-4.94 uIU/ml), free triiodothyronine (T3) 11.94 pg/ml (normal: 2.0-4.4 pg/ml), and free thyroxine (T4) >5 ng/dl (normal: 0.70-1.48 ng/dl). Thyroid storm was suspected and she was treated with hydrocortisone, propylthiouracil, Lugol iodine, and beta-blocker and her symptoms improved in 10 days with resolution of the weakness, confirming the diagnosis. Besides highlighting this association, this report demonstrates the importance of conducting thyroid function tests in patients presenting with axonal neuropathy. In patients having weakness in all four limbs and presenting with multiple comorbidities, we need to exclude medical reasons before starting treatment for GBS, such as in our case where it was thyrotoxicosis.

Widespread lytic lesions-A metastatic or vasculitic process?

INTRODUCTION: This case highlights the complexities in the initial diagnosis and investigations of widespread lytic lesions initially perceived to be a widespread metastatic process and the consideration of alternative diagnosis. PRESENTATION OF CASE: A 57 year-old man with a background of psoriatic arthritis presented to the rheumatology department with lumbar back pain and sensory disturbance over L4/5. Magnetic resonance imaging (MRI) and bone scan identified lesions consistent with bony metastases at L5. The patient previously had a raised prostate specific antigen (PSA) of 10.8µg/L (normal<4) but prostate biopsy was benign. Multiple metastatic deposits in the liver and kidneys (confirmed necrotic tissue on biopsy) were identified through further investigations. The initial diagnosis of malignancy was challenged after a positron emission tomography (PET) scan showed lesions highly suggestive of polyarteritis nodosa (PAN) and subsequent magnetic resonance angiogram (MRA) revealed stenosis and aneurysm in the renal artery in keeping with PAN. Therefore what was initially thought to be a widespread metastatic disease process was in fact the manifestation of a systemic vasculitic disease. DISCUSSION: PAN is a vasculitis that predominantly involves small to medium-sized vessels. The disease can affect any site in the body, but holds a predisposition for organs such as kidneys, heart and the gastrointestinal tract. Differential diagnosis of PAN should be considered in patients with widespread lytic lesions. CONCLUSION: Due to the pathological nature of PAN and its variable clinical manifestations that add to the challenges of its diagnosis, one must hold a high clinical suspicion, even in urological conditions.

The Use of Transperineal Sector Biopsy as A First-Line Biopsy Strategy: A Multi-Institutional Analysis of Clinical Outcomes and Complications.

PURPOSE: Systematic transrectal ultrasound biopsies have been the first-line biopsy strategy in men with suspected prostate cancer for over 30 years. Transperineal biopsy is an alternative approach but has been predominately reserved as a repeat biopsy strategy and not widely used as a first-line approach. This study evaluates the diagnostic and clinical outcomes of transperineal sector biopsy (TPSB) as a first-line biopsy strategy in the diagnosis and management of prostate cancer. MATERIALS AND METHODS: A multi-institutional review of 402 consecutive patients who underwent primary transperineal sector biopsy. All patients had no prior history of prostate biopsy. TPSB was carried out as a day-case procedure under general or regional anaesthesia. The cancer detection rate, location and complications for all cases were evaluated. RESULTS: Prostate cancer was identified in 249 patients (61.9%) and was comparably sited across anterior, middle and posterior sectors. The disease was clinically significant (Gleason 3+4 or > 4mm maximum cancer length) in 187 patients (47%). Post biopsy urinary retention occurred in 6 patients (1.5%). Hematuria requiring overnight hospital admission occurred in 4 patients (1.0%). There were no cases of urosepsis. CONCLUSIONS: As a primary diagnostic strategy, TPSB is a safe and effective technique with high cancer detection rates. It also offers an attractive compromise to more extensive transperineal protocols, which can be more time-consuming and associated with higher morbidity. .

An unrecognised case of metabolic acidosis following neobladder augmentation cystoplasty.

INTRODUCTION: We present a case where there was a delay in the diagnosis of severe metabolic acidosis in a patient with an orthotopic neobladder. There are a growing number of patients with orthotopic neobladders and a wider range of clinicians are encountering these patients. A delay in the diagnosis can lead to significant morbidity but if identified early it can be easily treated. PRESENTATION OF CASE: A 59-year old patient with a recent neobladder augmentation cystoplasty was admitted under the medical team with a metabolic acidosis which was incorrectly presumed to be secondary to urosepsis. His condition rapidly deteriorated until a surgical review identified hyperchloremic metabolic acidosis secondary to neobladder augmentation. The patient required admission to the intensive care unit where he was treated with intravenous alkalising therapy which produced rapid metabolic improvement. Following a full recovery, he underwent neo-bladder excision and ileal conduit formation. DISCUSSION: Hyperchloraemic metabolic acidosis develops due to the bowel segment absorbing urinary constituents including ammonium, hydrogen ions and chloride in exchange for sodium and bicarbonate. It can be diagnosed by careful interpretation of the arterial blood gas and calculation of the anion gap. This hyperchloraemic metabolic acidosis can be corrected with alkalizing agents combined with catheterisation. CONCLUSION: Hyperchloremic metabolic acidosis is a well-established complication of urinary diversion. Patient with orthotopic neobladder with high residual urine and large capacity are at even higher risk of metabolic acidosis. This information should be clearly documented in the post-operative discharge documentation to ensure early recognition by non-specialists.

Management of ureteropelvic junction obstruction in adults.

Ureteropelvic junction obstruction (UPJO) is characterized by impaired flow of urine from the renal pelvis to the ureter. Untreated disease can result in renal impairment making effective management crucial. A combination of CT imaging and diuretic renography is typically used for diagnosis. CT is the investigation of choice for obtaining anatomical information about UPJO and can help to identify potential causes. Diuretic renography is best for providing functional information about UPJO. A variety of open and minimally invasive surgical techniques are available for treatment of UPJO. Traditionally open pyeloplasty has been the standard of care but minimally invasive surgical techniques have become increasingly popular. Endopyelotomy has a lower success rate than other modalities (42-90% depending on the approach), but is associated with reduced pain and shorter convalescence. Laparoscopic pyeloplasty and robot-assisted pyeloplasty have similar success rates to open pyeloplasty (>90%), with the additional advantages of significantly reduced morbidity and shorter convalescence. More long-term outcome data for minimally invasive surgical techniques are awaited.

An overview of the use and implementation of checklists in surgical specialities - a systematic review.

INTRODUCTION: Surgical procedures present an immense risk to patients, and adverse patient outcomes are frequently due to substandard non-technical skills amongst surgical staff. The implementation of a 19-item Surgical Safety Checklist, developed by the World Health Organization, is being enforced in operating theatres globally. The objective is to systematically analyze published literature to assess the use of the WHO Surgical Safety Checklist and their impact in on patient safety. METHODS: An English literature search was carried out using MEDLINE, EMBASE and PsycINFO databases. Relevant information was extracted relating to surgical specialities, compliance with the checklist, effects of checklist use on patient outcomes, and staff perceptions of the checklist. Selection was restricted to articles that used the WHO Surgical Safety Checklist. RESULTS: The literature search found 916 potentially relevant articles, which were narrowed down following an abstract review and a full text review. A final total of 16 studies were identified that observed the use of checklists in various surgical specialties; all surgical specialities (n-10), pediatric surgery (n-2), orthopedic surgery (n-2), otorhinolaryngology surgery (n-2). DISCUSSION: Surgical checklists have been shown to significantly improve patient outcomes subsequent to surgery, and therefore their use is being widely encouraged and accepted. Continual feedback could be given to maintain high checklist compliance, and thus high patient safety. SUMMARY: The recent use of checklists in surgery has shown improvements in patient outcomes post-operatively. A review was conducted to establish the impact of the checklist on different surgical specialities.

Deep brain stimulation surgical techniques.

Stereotactic techniques for placement of deep brain stimulation (DBS) electrodes have undergone continuous refinement since the introduction of human stereotaxis in the 1940s. Volumetric imaging techniques, including magnetic resonance imaging and computed tomography, have replaced ventriculography, and increasingly sophisticated computer systems now allow highly refined targeting of subcortical structures. This chapter reviews the underlying principles of stereotactic surgery, including imaging, targeting, and registration, and describes the surgical approach to DBS placement using both framed and frameless techniques.