Phacoemulsification in Complex Cases

BackgroundMedical problems are often complex and ill-structured. In formulating the problem, one has to discriminate pertinent elements from irrelevant information in order to effectively find a solution. In this observation study, we describe how medical students formulate the problem of a complex case.Methods32 third year medical students were presented with a complex case of endocarditis. They were asked to synthesize the case and give the best formulation of the problem. They were then asked to provide a diagnosis. A subsequent group of 25 students were presented with the problem already formulated and were also asked for the diagnosis. We analyzed the student's problem formulations using the presence or absence of essential elements of the case, the use of higher-order concepts and the use of relations between concepts.Results12/32 students presented with the case made the correct diagnosis. Diagnostic accuracy was significantly associated with the use of higher-order concepts and relations between concepts. Establishing explicit relations was particularly important. Almost all students who missed the diagnosis could not elicit any relations between concepts but only reported factual observations. When presented with an already formulated problem, 19/25 students made the correct diagnosis. (p < 0.05)ConclusionWhen faced with a complex new case, students may not have the structured knowledge to recognize the nature of the problem. They have to build new schema or problem representation. Our observations suggest that this process involves using higher-order concepts and establishing new relations between concepts. The fact that students could recognize the disease when presented with a formulated problem but had more difficulty when presented with the original complex case indicates that knowledge of the clinical features may be necessary but not sufficient for problem formulation. Our hypothesis is that problem formulation represents a distinct ability.

Older people with severe and complex needs are a major challenge in the realm of community health. However, despite the importance of the issue there is a lack of knowledge regarding complex cases of community-dwelling older people with cognitive impairment (hereafter referred to as "complex cases").The first aim of this study was to develop a framework for the comprehensive assessment and analysis of the issues faced by complex cases. The second aim was to identify the relationships between these issues and the clinical stages of dementia using the Clinical Dementia Rating (CDR). A consecutive case series study was conducted using the records of 293 cases in municipal psychogeriatric services. Descriptions regarding the issues faced by complex cases were extracted from the case records and categorized. Next, trends according to CDR were analyzed. The association between each category and the CDR was then examined by multivariate analysis. The issues faced by complex cases were categorized into five categories: A, Mental Health Issues; B, Physical Health Issues; C, Family Issues; D, Issues of Neighborhood Communication; and E, Financial Issue. The higher the CDR score, the higher the frequency of categories C and E, the lower the frequency of category A, and the more categories each case faced. After adjusting for possible confounders, CDRs were associated with the categories of issues faced by complex cases. The analytical framework developed in the present study will help in the categorization of the complexity of complex cases and the development of intervention strategies. In addition, by incorporating the perspective of the clinical stage of dementia, more effective support can be provided. Geriatr Gerontol Int 2022; 22: 997-1004.

A better insight in how the biopsychosocial factors influence patient outcome(s) may provide information that helps selecting the optimal pain management for a specific group. Categorization was made in the prospective DATAPAIN registry, in which patients with pain severity (Numeric Rating Scale [NRS]: 7-10), depression or anxiety (Hospital Anxiety and Depression Scale: > 10), and pain catastrophizing (Pain Catastrophizing Scale: > 31) were identified as complex cases. Patient outcomes; treatment satisfaction on the Patient Global Impression of Change (PGIC), pain relief (NRS), pain interference on the Brief Pain Inventory (BPI) and quality of life indicator General Perceived Health (GPH) were evaluated. Logistic regression analyzed if belonging to the complex cases showed modification in the outcome of the PGIC and GPH. Linear regression was observed if complex cases differed in average reduction in pain relief and interference compared to non-complex cases. 1637 patients were included, of which 345 (21.08%) were considered complex cases. The changes in scores of pain relief and BPI active subscale were not significantly different between groups. The BPI affective subscale had a different change in score (-0.509; p: 0.002). The complex cases had an odds ratio (OR) of 0.59 (95% confidence interval [CI]: 0.36-0.77) on treatment satisfaction compared to non-complex cases, and an OR of 0.28 (95% CI: 0.11-0.56) on the GPH. When treating patients with complex cases, desired treatment outcome(s) should be recognized by specialists and patients, as these may be less likely to occur.

The authors sought to evaluate the impact of virtual reality (VR) applications for preoperative planning and rehearsal on the total procedure time of microsurgical clipping of middle cerebral artery (MCA) ruptured and unruptured aneurysms compared with standard surgical planning. A retrospective review of 21 patients from 2016 to 2019 was conducted to determine the impact on the procedure time of MCA aneurysm clipping after implementing VR for preoperative planning and rehearsal. The control group consisted of patients whose procedures were planned with standard CTA and DSA scans (n = 11). The VR group consisted of patients whose procedures were planned with a patient-specific 360° VR (360VR) model (n = 10). The 360VR model was rendered using CTA and DSA data when available. Each patient was analyzed and scored with a case complexity (CC) 5-point grading scale accounting for aneurysm size, incorporation of M2 branches, and aspect ratio, with 1 being the least complex and 5 being the most complex. The mean procedure times were compared between the VR group and the control group, as were the mean CC score between the groups. Comorbidities and aneurysm conduction (ruptured vs unruptured) were also taken into consideration for the comparison. The mean CC scores for the control group and VR group were 2.45 ± 1.13 and 2.30 ± 0.48, respectively. CC was not significantly different between the two groups (p = 0.69). The mean procedure time was significantly lower for the VR group compared with the control group (247.80 minutes vs 328.27 minutes; p = 0.0115), particularly for the patients with a CC score of 2 (95% CI, p = 0.0064). A Charlson Comorbidity Index score was also calculated for each group, but no statistical significance was found (VR group, 2.8 vs control group, 1.8, p = 0.14). In this study, usage of 360VR models for planning the craniotomy and rehearsing with various clip sizes and configurations resulted in an 80-minute decrease in procedure time. These findings have suggested the potential of VR technology in improving surgical efficiency for aneurysm clipping procedures regardless of complexity, while making the procedure faster and safer.

The goal of independent component analysis (ICA) is to decompose observed signals into components as independent as possible. In linear instantaneous blind source separation, ICA is used to separate linear instantaneous mixtures of source signals into signals that are as close as possible to the original signals. In the estimation of the so-called demixing matrix one has to distinguish two different factors: 1. Variance of the estimated inverse mixing matrix in the noiseless case due to randomness of the sources. 2. Bias of the demixing matrix from the inverse mixing matrix: This chapter studies both factors for circular and noncircular complex mixtures. It is important to note that the complex case is not directly equivalent to the real case of twice larger dimension. In the derivations, we aim to clearly show the connections and differences between the complex and real cases. In the first part of the chapter, we derive a closed-form expression for the CRB of the demixing matrix for instantaneous noncircular complex mixtures. We also study the CRB numerically for the family of noncircular complex generalized Gaussian distributions (GGD) and compare it to simulation results of several ICA estimators. In the second part, we consider a linear noisy noncircular complex mixing model and derive an analytic expression for the demixing matrix of ICA based on the Kullback-Leibler divergence (KLD). We show that for a wide range of both the shape parameter and the noncircularity index of the GGD, the signal-to-interference-plus-noise ratio (SINR) of KLD-based ICA is close to that of linear MMSE estimation. Furthermore, we show how to extend our derivations to the overdetermined case (\(M>N\)) with circular complex noise.

Diagnostic pitfalls and complex cases in MS.

Significant improvements in percutaneous coronary intervention (PCI) technology have enabled cardiovascular procedures to be performed without onsite cardiac surgery facilities. However, little is known about the association between onsite cardiac surgical support and long-term outcomes of PCI, particularly among emergent and complex cases. We investigated whether the presence or absence of cardiovascular surgery affects the long-term prognosis after PCI, emergent and complex elective cases. The SHINANO 5-year registry, a prospective, observational, and multicenter cohort study registry in Nagano, Japan, consecutively included 1665 patients who underwent PCI between August 2012 and July 2013. The procedures were performed at 11 hospitals with onsite cardiac surgery facilities [onsite surgery (+) group; n = 1257] and 8 hospitals without onsite cardiac surgery facilities [onsite surgery (−) group; n = 408]. The primary endpoint was all-cause mortality and the secondary endpoint was major adverse cardiac and cerebrovascular events [MACCE: all-cause death, Q-wave myocardial infarction, non-fatal stroke, and target lesion revascularization]. The onsite surgery group (+) had a lower rate of emergent PCI and ST-segment elevation myocardial infarction (40.8% vs. 51.7%, p < 0.01 and 24.9% vs. 39.2%, p < 0.01, respectively), and a higher prevalence of hemodialysis and history of peripheral artery disease (7.6% vs. 2.45%, p < 0.01 and 12.1% vs. 6.9%, p < 0.01, respectively). However, the Kaplan–Meier analysis showed no difference in the 5-year mortality rate (16.4% vs. 15.2%, p = 0.421) and MACCE incidence (31.6% vs. 28.9%, p = 0.354) between the groups. Also, there were no differences in the mortality rate and incidence of MACCE among emergent cases of ST-segment elevation myocardial infarction and complex elective cases who underwent PCI. Long-term outcomes of PCI appear to be comparable between institutions with and without onsite cardiac surgical facilities.

History matching integrated with uncertainty reduction is a key process in the closed loop reservoir development and management methodology which is used for decision analysis related to the development &amp; management of petroleum fields. Despite developments over the last decades in history matching &amp; uncertainty analysis, the challenge of capturing complex interaction among several attributes and several reservoir responses acting simultaneously for complex models still remains. This paper describes the use of a probabilistic and multi-objective history matching integrated with uncertainty reduction as a systematic and iterative process for obtaining a set of reservoir models that honors dynamic data in a complex field case. The methodology is an iterative process that simultaneously matches different objective functions, one for each well production profile. The procedure uses a re-characterization step, where the uncertainties of the attributes (represented by their probability density functions) are updated using indicators that show global and local problems and a correlation matrix to capture the interaction between several reservoir uncertainties and the different objective functions. The methodology was applied to the Norne Field benchmark case considering production data up to 2001 and the remaining part of the provided history is used to estimate the quality of production forecast. The major benefit derived from the application of the methodology was the identification of global and local problems. The initial reservoir models presented high discrepancies between simulated and observed data. The use of independent objective functions in conjunction with the concise plot that is based on the normalized quadratic error of each production data highlighted when new parametrization of the reservoir was necessary. New reservoir attributes were added, such as separated permeability curves for each reservoir formation and new gas permeability curves that better describe the fluid behavior. The initial number of uncertain attributes was twenty seven; the correlation matrix clearly showed which one of those had major influence on the results. Some attributes with significant impact in the study were water-oil and gas-oil contact and faults transmissibility. We updated the probability of the most influencing attributes in order to identify the uncertain levels that improved the history match results. The methodology integrated the process of history matching with uncertainty analysis, addressing both processes simultaneously for a complex case. The methodology was effective and simple to use, even in the complex case study where the reservoir characterization is important.

Background/Objectives: Complex cases in pediatric surgery involving multiple congenital anomalies pose significant diagnostic and therapeutic challenges. These conditions require coordinated interdisciplinary care tailored to the individual patient. We present a case of syndromic congenital anomalies in a neonate, later diagnosed with CHARGE syndrome, to illustrate the importance of staged, multidisciplinary management. Methods: A 34-year-old woman in her third pregnancy developed significant polyhydramnios at 31 weeks of gestation, followed by preterm labor. The neonate presented with esophageal atresia with tracheoesophageal fistula (EA/TEF), intrathoracic stomach, aortic coarctation, patent ductus arteriosus, atrial septal defect, and bilateral choanal atresia. A structured treatment protocol was developed and implemented at Klinikum Stuttgart by an interdisciplinary team comprising gynecology, pediatric surgery, cardiology, ENT, neonatology, and genetics. Results: Initial pediatric surgical procedures included ligation of the tracheoesophageal fistula, repositioning of the intrathoracic stomach, and primary esophageal anastomosis. Cardiovascular anomalies were managed through staged interventions. Bilateral choanal atresia was surgically corrected. Genetic testing confirmed CHARGE syndrome. Postoperative care included respiratory support, enteral nutrition, and regular esophageal dilations. Due to persistent reflux esophagitis, antireflux surgery is planned. Conclusions: This case underscores the importance of a highly individualized and interdisciplinary approach in the management of syndromic congenital anomalies. The presence of CHARGE syndrome with multiple system involvement required careful staging of surgical interventions and long-term coordination of follow-up care. Early genetic diagnosis and integrated team planning were critical in optimizing outcomes in this complex neonatal case.

Tethered cord release (TCR) is the gold standard treatment for tethered cord syndrome (TCS); however, there are significant shortcomings including high rates of retethering, especially in complex and recurrent cases. Spinal column shortening (SCS) is an alternative treatment for TCS intended to avoid these shortcomings. Early studies were limited to case reports and smaller case series; however, in recent years, larger case series and small cohort studies have been conducted. Given the increase in available data, a repeat systematic review and meta-analysis is warranted to assess the safety and efficacy of SCS for TCS. The authors conducted a systematic review using MEDLINE (OVID), Embase (Elsevier), and Web of Science records dating from 1944 to July 2021 to identify all articles investigating SCS for TCS. They performed standard and individual patient data (IPD) meta-analyses, with 2 independent reviewers using PRISMA-IPD guidelines. Primary outcomes were improvement of preoperative clinical symptoms of pain, motor weakness, and bladder and bowel dysfunction, and also surgical complication rate. Secondary outcomes included urodynamic improvement and health-related quality-of-life outcomes determined using patient-reported outcome tools. Individual study quality assessment was performed using a standardized assessment tool for case reports/series, and publication bias was assessed using funnel plot analyses. The review yielded 15 studies with 191 cases of TCS treated with SCS. IPD were available in 11 studies with 89 cases. The average age at time of surgery was 28.0 years (range 5-76 years). The average follow-up time was 33.2 months (range 7-132 months). Improvement was observed at last follow-up in 60 of 70 (85.7%) patients with preoperative pain, in 38 of 60 (60.3%) patients with preoperative weakness, and in 36 of 76 (47.4%) patients with preoperative bladder or bowel dysfunction. Complications of CSF leak, new neurological deficit, wound infection, or reoperation occurred in 4 of 89 (4.5%) patients. SCS may be considered a safe and efficacious treatment option for TCS in children and adults (level C evidence; class IIb recommendation), especially for recurrent and complex cases. Current evidence is likely to be affected by selection and publication bias. Prospective comparative studies of SCS and TCR for TCS are recommended to determine long-term duration of outcomes, long-term safety in skeletally immature children, and exact indications of SCS versus traditional TCR.

Some cases are thought to be more complex and difficult to treat, although there is little consensus on how to define complexity in psychological care. This study proposes an actuarial, data-driven method of identifying complex cases based on their individual characteristics. Clinical records for 1,512 patients accessing low- and high-intensity psychological treatments were partitioned in 2 random subsamples. Prognostic indices predicting post-treatment reliable and clinically significant improvement (RCSI) in depression (Patient Health Questionnaire-9; Kroenke, Spitzer, & Williams, 2001) and anxiety (Generalized Anxiety Disorder-7; Spitzer, Kroenke, Williams, & Löwe, 2006) symptoms were estimated in 1 subsample using penalized (Lasso) regressions with optimal scaling. A PI-based algorithm was used to classify patients as standard (St) or complex (Cx) cases in the second (cross-validation) subsample. RCSI rates were compared between Cx cases that accessed treatments of different intensities using logistic regression. St cases had significantly higher RCSI rates compared to Cx cases (OR = 1.81 to 2.81). Cx cases tended to attain better depression outcomes if they were initially assigned to high-intensity (vs. low intensity) interventions (OR = 2.23); a similar pattern was observed for anxiety but the odds ratio (1.74) was not statistically significant. Complex cases could be detected early and matched to high-intensity interventions to improve outcomes. (PsycINFO Database Record

One approach to the analysis of the high signal-to-noise ratio (SNR) capacity of noncoherent wireless communication systems is to ignore the noise component of the received signal in the computation of its differential entropy. In this paper, we consider the error incurred by this approximation when the transmitter and the receiver have one antenna each and when the noise has a Gaussian distribution. We consider the complex and real cases, and we show that when the probability density function (pdf) of the signal component of the received signal is piecewise differentiable, the approximation error decays as 1/SNR, which tightens the available result that the error decays as o(1). In addition, we consider the special instance in which the signal component of the received signal corresponds to a signal transmitted over a channel with a Gaussian fading coefficient. For that case, we provide explicit expressions for the first nonconstant term of the Taylor expansion of the differential entropy, and we invoke Schwartz's inequality to obtain an efficiently computable bound on it. Our results are supported by numerical examples.

The population of ageing adults with congenital heart disease (ACHD) is increasing; surgery in these patients presents major difficulties in management. A great debate has developed about whether these patients should be cared for at an adult or paediatric hospital and by an acquired or congenital cardiac surgeon. We analysed data of the surgical treatment of ACHD from the Italian cardiac surgery centres in 2016, focusing on the type of surgery performed, where these patients were operated on and by whom. Ninety-two Italian cardiac surgery centres were contacted and 70 centres participated in this study. We collected data on the types of cardiac operations performed in congenital heart defect patients older than 18 years. In 2016, a total of 913 patients with ACHD were operated on: 440 by congenital cardiac surgeons (group I) in centres with paediatric and adult cardiac surgery units, and 473 by adult cardiac surgeons (group II) in centres with exclusively adult cardiac surgery units. Pathologies of the right ventricular outflow tract were the most frequent diseases treated in group I and pathologies of the left ventricular outflow tract in group II. Group I included more complex and heterogeneous cases than group II. Surgery for ACHD represented 12% of the activity of congenital cardiac surgeons and only 1% of the activity of adult cardiac surgeons. In Italy, ACHD patients are operated on both by congenital and adult cardiac surgeons. Congenital cardiac surgeons working in centres with both paediatric and adult cardiac surgery are more involved with ACHD patients and with more complex cases.

Reducing the risk of violent and aggressive behaviour in patients with schizophrenia remains a clinical priority. There is emerging evidence to suggest that the second-generation antipsychotic, clozapine, is effective at reducing this risk in patients with schizophrenia and some evidence to suggest that it may be best in selected patients. We conducted a systematic literature search in March 2011 of all prospective and retrospective studies, which investigated clozapine's anti-aggressive effects in a variety of mental disorders. The review identified six animal studies, four randomized controlled trials, 12 prospective non-controlled studies and 22 retrospective studies, with four case studies. We found considerable evidence in support of clozapine's ability to reduce violent and aggressive behaviour. Clozapine's anti-aggressive effect was most commonly explored in patients with schizophrenia, with less evidence available for other psychiatric disorders, including borderline personality disorder, autistic spectrum disorders, post-traumatic stress disorder, bipolar disorder and learning disability. There was mixed evidence to address the question of whether or not clozapine was any more effective than other antipsychotics. In the case of schizophrenia, there was evidence to suggest that clozapine's anti-aggressive effect was more marked particularly in those with treatment-resistant illness. Its anti-aggressive effects appeared to be 'specific', being to some extent greater than both its more general antipsychotic and sedative effects. There were significant methodological inconsistencies in the studies we identified, particularly surrounding patient recruitment criteria, the definition and measurement of violence and the lack of randomized, controlled trials. Data on therapeutic monitoring were also limited. Clozapine can reduce violence and persistent aggression in patients with schizophrenia and other psychiatric disorders. It may offer an advantage over other antipsychotics, although perhaps exclusively in the case of traditionally defined 'treatment resistance' or more broadly defined 'complex cases' with co-morbidity. Larger, randomized, blinded, controlled studies with robust characterization of participants, and standardized measures of violence and aggression are, however, needed to fully understand this link and explore the possible mechanisms.

Outcomes of both complex and isolated cases of infants with large stomach on fetal ultrasound