Extended Analysis of Raman Spectra Using Artificial Intelligence Techniques for Colorectal Abnormality Classification

Raman spectroscopy (RS) techniques are attracting attention in the medical field as a promising tool for real-time biochemical analyses. The integration of artificial intelligence (AI) algorithms with RS has greatly enhanced its ability to accurately classify spectral data in vivo. This combination has opened up new possibilities for precise and efficient analysis in medical applications. In this study, healthy and cancerous specimens from 22 patients who underwent open colorectal surgery were collected. By using these spectral data, we investigate an optimal preprocessing pipeline for statistical analysis using AI techniques. This exploration entails proposing preprocessing methods and algorithms to enhance classification outcomes. The research encompasses a thorough ablation study comparing machine learning and deep learning algorithms toward the advancement of the clinical applicability of RS. The results indicate substantial accuracy improvements using techniques like baseline correction, L2 normalization, filtering, and PCA, yielding an overall accuracy enhancement of 15.8%. In comparing various algorithms, machine learning models, such as XGBoost and Random Forest, demonstrate effectiveness in classifying both normal and abnormal tissues. Similarly, deep learning models, such as 1D-Resnet and particularly the 1D-CNN model, exhibit superior performance in classifying abnormal cases. This research contributes valuable insights into the integration of AI in medical diagnostics and expands the potential of RS methods for achieving accurate malignancy classification.

Biochemical differentiation between cancerous and normal human colorectal tissues by micro-Raman spectroscopy

Human colorectal tissues obtained by ten cancer patients have been examined by multiple micro-Raman spectroscopic measurements in the 500-3200 cm^-1 range under 785 nm excitation. Distinct spectral profiles are recorded from different spots on the samples: a predominant 'typical' profile of colorectal tissue, as well as those from tissue topologies with high lipid, blood or collagen content. Principal component analysis identified several Raman bands of amino acids, proteins and lipids which allow the efficient discrimination of normal from cancer tissues, the first presenting plurality of Raman spectral profiles while the last showing off quite uniform spectroscopic characteristics. Tree-based machine learning experiment was further applied on all data as well as on filtered data keeping only those spectra which characterize the largely inseparable data clusters of 'typical' and 'collagen-rich' spectra. This purposive sampling evidences statistically the most significant spectroscopic features regarding the correct identification of cancer tissues and allows matching spectroscopic results with the biochemical changes induced in the malignant tissues.

DIRECT MEASUREMENTS OF SKIN, EYE LENS AND THYROID DOSE DURING PEDIATRIC BRAIN CT EXAMINATIONS

Pediatric brain computed tomography (CT) is identified as the most frequent CT examination in children. The aim of the study is the direct measurement of skin, eye lens and thyroid dose in pediatric patients during brain CT examinations. The study included 35 pediatric patients who underwent brain CT examinations. The patients were categorized in three age groups: Group A (age range: 0.8-1 years), Group B (age range: 2.0-4.9 years) and Group C (age range: 5.5-15.5 years). thermoluminescent dosimeters (TLDs) were placed on the eyes, the frontal region of the head, the mastoid apophysis and the thyroid gland. The skin dose was found 16.6 ± 1.5, 38.8 ± 5.1 and 41.7 ± 9.4 mGy for Groups A, B and C, respectively. The mean dose for the eye lens was 10.5 ± 3.3, 29.9 ± 8.6 and 34.2 ± 14.9 mGy and for the thyroid 1.7 ± 0.4, 2.4 ± 0.5 and 1.9 ± 0.4 mGy for Groups A, B and C, respectively. In vivo dosimetry using TLDs proved to be an efficient method. Gantry tilting and patient's set-up seem to significantly affect eye lens dose.

Guidewire-induced coronary artery perforation and tamponade during PCI: in-hospital outcomes and impact on long-term survival

BACKGROUND

Guidewire-induced coronary perforation (CP) rate is reported to have increased.

METHODS

We analyzed 23,399 PCIs and identified 73 patients complicated by CP, of which 31 were guidewire induced. Patients were divided into two groups: group A (guidewire-induced CP) and group B (non-guidewire induced CP). Characteristics and outcomes were compared and a multivariate model was developed to evaluate the independent contribution of guidewire-induced CP on mortality.

RESULTS

Group A patients had more PCIs on CTO lesions (P=.001). Group A showed a trend for higher tamponade (P=.08). Delayed tamponade occurred only in group A (P<.001). Polytetrafluoroethylene stents were used more often in group B (P<.01). In-hospital mortality was similar between groups (3.2% vs. 7.1%; P=NS). Emergent cardiac surgery was needed in 5.5% of all CP patients and was similar between groups. Group A had a trend for better survival (hazard ratio [HR], 0.37; 95% CI, 0.12-1.10; P=.07). Tamponade conferred a 3-fold increase in the long-term probability of death (HR, 2.95; 95% CI, 1.07-8.13; P=.04). Guidewire-induced CP during elective PCI had the best survival (HR, 0.31; 95% CI, 0.11-0.87; P=.03).

CONCLUSIONS

Guidewire-induced CP rate is low. In-hospital mortality was similar for patients with guidewire-induced and non-guidewire induced perforations. Presentation of tamponade was occasionally delayed and associated with increased early and late death. Percutaneous coronary intervention of lesions with an expected increased risk of CP should be undertaken with consideration of the short- and long-term risk, particularly during non-elective PCI since tamponade in this setting increased the risk of late death by nearly 3-fold.

Cardiac tamponade complicating coronary perforation during angioplasty: short-term outcomes and long-term survival

BACKGROUND

Cardiac tamponade constitutes the most severe clinical consequence of a coronary perforation (CP) during percutaneous coronary intervention (PCI).

METHODS

We analyzed 23,399 PCIs and identified 73 patients complicated by CP (0.31%), of which 26 developed tamponade (0.11%). Patients were divided into two groups: CP with tamponade (group A) and CP without tamponade (group B). Characteristics and outcomes were compared and a multivariate model was developed to evaluate the independent contribution of tamponade on mortality.

RESULTS

All patients with tamponade were treated with pericardiocentesis. Tamponade increased the risk of death by more than 3-fold (odds ratio [OR] = 3.3; 95% confidence interval [CI],1.01-10.6; P=.047) relative to patients with CP but no tamponade. CP with tamponade during non-elective PCI carried a significantly worse long-term prognosis (P=.001) than the same complications during elective PCI. The use of glycoprotein IIb/IIIa inhibitors and bivalirudin did not differ between groups. Polytetrafluoroethylene-covered stents were used similarly between the two groups, while coil embolization was used more often in group A (P=.003). Emergent cardiac surgery was needed in 3 patients (11.5%) in group A versus 1 patient (2.1%) in group B.

CONCLUSIONS

Tamponade complicating CP during PCI has short- and long-term major adverse effects. In-hospital mortality after tamponade and referral for emergent surgical treatment have decreased. Nonetheless, tamponade in this setting increases risk of death by >3-fold. PCI of complex lesions with an expected increased risk of perforation should be undertaken cautiously among patients with non-elective PCI because of increased early and late risk of death.

Radiation-free distal locking of intramedullary nails: evaluation of a new electromagnetic computer-assisted guidance system

Distal locking of intramedullary nails (IMNs) is a difficult part of intramedullary nailing (IMN) that could be time-consuming and expose the surgeon, the surgery personnel and the patient to a considerable amount of radiation as fluoroscopy is usually guiding the procedure. Utilization of electromagnetic fields for that purpose offers an attractive alternative. The SURESHOT™ Distal Targeting System (Smith & Nephew, Inc., Memphis, TN, USA) is a novel commercially available radiation-free aiming system that utilizes computerized electromagnetic field tracking technology for the distal locking of IMNs. In order to evaluate the efficacy of the system we conducted the present study. Nineteen patients (six females-thirteen males, mean age 39.5 years, range 17-85 years) with closed diaphyseal fracture of the femur (eight patients) or the tibia (eleven patients) were treated with IMN using the SURESHOT™ Distal Targeting System for the distal interlocking. All targeting attempts were successful at first try and followed by correct positioning of the screws. Mean time for distal locking of tibial IMNs (two screws) was 219sec (range 200-250sec). Mean time for distal locking of femoral IMNs (two screws) was 249 (range 220-330sec). In the current study the SURESHOT™ Distal Targeting System proved to be accurate, fast and easy to learn.

Opposing effects of bortezomib-induced nuclear factor-κB inhibition on chemical lung carcinogenesis

Since recent evidence indicates a requirement for epithelial nuclear factor (NF)-κB signaling in lung tumorigenesis, we investigated the impact of the NF-κB inhibitor bortezomib on lung tumor promotion and growth. We used an experimental model in which wild-type mice or mice expressing an NF-κB reporter received intraperitoneal urethane (1 g/kg) followed by twice weekly bortezomib (1 mg/kg) during distinct periods of tumor initiation/progression. Mice were serially assessed for lung NF-κB activation, inflammation and carcinogenesis. Short-term proteasome inhibition with bortezomib did not impact tumor formation but retarded the growth of established lung tumors in mice via effects on cell proliferation. In contrast, long-term treatment with bortezomib resulted in significantly increased lung tumor number and size. This tumor-promoting effect of prolonged bortezomib treatment was associated with perpetuation of urethane-induced inflammation and chronic upregulation of interleukin-1β and proinflammatory C-X-C motif chemokine ligands (CXCL) 1 and 2 in the lungs. In addition to airway epithelium, bortezomib inhibited NF-κB in pulmonary macrophages in vivo, presenting a possible mechanism of tumor amplification. In this regard, RAW264.7 macrophages exposed to bortezomib showed increased expression of interleukin-1β, CXCL1 and CXCL2. In conclusion, although short-term bortezomib may exert some beneficial effects, prolonged NF-κB inhibition accelerates chemical lung carcinogenesis by perpetuating carcinogen-induced inflammation. Inhibition of NF-κB in pulmonary macrophages appears to play an important role in this adverse process.

Which are the most important discriminatory items for subclassifying non-specific low back pain? A Delphi study among Greek health professionals

RATIONALE, AIMS AND OBJECTIVES

Developing homogenous low back pain (LBP) classification groups is recommended for enhancing clinical outcomes. However, an important step towards the development of specific subgroups is the selection and consensus agreement among health professionals on the discriminatory clinical items (sings and symptoms) that should be included in the classification process. Thus, this study's objective was to develop a list of clinical features for the assessment of LBP by health care providers within Greece, which are believed to be discriminatory in identifying LBP subgroups.

METHODS

A random sample stratified by geographical region and work status of 150 Greek physiotherapists (PTs) participated in a two-round Delphi study. PTs were asked to obtain consensus and hierarchy, the most important items out of a list of evaluating/diagnostic features believed to be discriminatory for LBP patients. These items included 80 clinical features and were generated in by PTs and doctors previous work.

RESULTS

Second-round questionnaires were returned by 112 PTs (74.6% response rate). A total of 66 clinical features were rated as important discriminatory items in LBP assessment. Clinical items included characteristics of present symptoms and the history's condition, general medical history, information regarding patient function, patients' attitudes regarding movement, diagnosis, expectations, fear-avoidance beliefs as well as aspects of a physical examination including observation, active and passive movements, neurological and muscular examination.

CONCLUSIONS

This is the first study identifying important clinical items for LBP patients in Greece. It may be that these features are 'discriminatory' for different LBP subsets; however, further research is needed.

The decline in PCI complication rate: 2003-2006 versus 1999-2002

INTRODUCTION

Technical improvements permit the performance of percutaneous coronary interventions (PCI) reliably and safely. However, adverse events during such procedures have still not been eliminated. The purpose of this study was to assess the current rates of complications from PCI, as well as any changes from 1999 to 2006.

METHODS

Prospectively collected Lenox Hill Hospital data were abstracted from the New York State PCI Report forms and a review of the Quality Improvement office database. The reported complications from 23,399 consecutive PCIs performed during an eight-year period (January 1999 to December 2006) were recorded. The one-month composite endpoint (CEP: death, myocardial infarction, stent thrombosis, stroke, or emergent cardiac surgery within one month of the PCI) and the one-month composite endpoint excluding stent thrombosis (CEPnoST) were evaluated.

RESULTS

Complications occurred in 3.36% of PCIs. The following complication rates were found: one month death rate 0.6%, death in the catheterization suite 0.047%, stent thrombosis (one month) 0.53%, presumed stent thrombosis (one month) 0.82%, myocardial infarction (MI: either Q or non-Q wave) 0.74%, emergent cardiac surgery 0.15%, stroke 0.29%, cardiac perforation 0.29%, retroperitoneal bleeding 0.18%, acute renal failure 0.28%, need for hemodialysis 0.17%, CEP 1.8% and CEPnoST 1.58%. When the complication rates from the most recent period (2003-2006) were compared with those from the earlier period (1999-2002), a statistically significant difference was found in total complications, CEP, CEPnoST, stroke, MI, and vascular complications.

CONCLUSIONS

Current rates of PCI complications remain low. The overall PCI complication rate was lower during the last four years of the study.

A-dip of the aortic valve by M-mode echocardiography

We present a case with the previously unreported finding of an a-dip in the M-mode tracing of the aortic valve. An a-dip is commonly seen in the M-mode tracing of the pulmonic valve motion, and represents near equalization of pulmonary artery and right ventricular end- -diastolic pressures during atrial contraction. M-mode echocardiography has become an ancillary study to the basic two-dimensional examination, but can often convey important features of cardiac hemodynamics quite elegantly, as the present case demonstrates.

Radial access - be prepared!

We present the case of a 46-year-old female patient that experienced recurrent stent thrombosis and underwent attempted primary PCI via the radial artery. Although radial artery cannulation with a 6 Fr sheath and the diagnostic angiography were successfully performed, the PCI could not be achieved because of failure to advance the 6 Fr guide through the radial artery, due to severe angulation of a high take-off radial artery, combined with a proximal radial artery stenosis.

The clinical and cultural factors in classifying low back pain patients within Greece: a qualitative exploration of Greek health professionals

RATIONALE, AIMS AND OBJECTIVES

Identifying homogenous subgroups of low back pain (LBP) patients is considered a priority in musculoskeletal rehabilitation and is believed to enhance clinical outcomes. In order to achieve this, the specific features of each subgroup need to be identified. The aim of this study was to develop a list of clinical and cultural features that are included in the assessment of LBP patients in Greece, among health professionals. This 'list' will be, utilized in a clinical study for developing LBP subgroups.

METHODS

Three focus groups were conducted, each one comprising health professionals with homogenous characteristics and all coordinated by a single moderator. There were: 11 physiotherapists (PTs) with clinical experience in LBP patients, seven PTs specialized in LBP management, and five doctors with a particular spinal interest. The focus of discussions was to develop a list of clinical and cultural features that were important in the examination of LBP. Content analysis was performed by two researchers.

RESULTS

Clinicians and postgraduates developed five categories within the History (Present Symptoms, History of Symptoms, Function, Psychosocial, Medical History) and six categories within the Physical Examination (Observation, Neurological Examination, Active and Passive Movements, Muscle Features and Palpation). The doctors identified four categories in History (Symptomatology, Function, Psychosocial, Medical History) and an additional in Physical Examination (Special Tests). All groups identified three cultural categories; Attitudes of Health Professionals, Patients' Attitudes and Health System influences.

CONCLUSION

An extensive Greek 'list' of clinical and cultural features was developed from the groups' analysis. Although similarities existed in most categories, there were several differences across the three focus groups which will be discussed.