Clinical applications of artificial intelligence in radiology.

The rapid growth of medical imaging has placed increasing demands on radiologists. In this scenario, artificial intelligence (AI) has become an attractive partner, one that may complement case interpretation and may aid in various non-interpretive aspects of the work in the radiological clinic. In this review, we discuss interpretative and non-interpretative uses of AI in the clinical practice, as well as report on the barriers to AI's adoption in the clinic. We show that AI currently has a modest to moderate penetration in the clinical practice, with many radiologists still being unconvinced of its value and the return on its investment. Moreover, we discuss the radiologists' liabilities regarding the AI decisions, and explain how we currently do not have regulation to guide the implementation of explainable AI or of self-learning algorithms.

Perceptual analysis of the reading of dermatopathology virtual slides by pathology residents.

CONTEXT: The process by which pathologists arrive at a given diagnosis-a combination of their slide exploration strategy, perceptual information gathering, and cognitive decision making-has not been thoroughly explored, and many questions remain unanswered. OBJECTIVE: To determine how pathology residents learn to diagnose inflammatory skin dermatoses, we contrasted the slide exploration strategy, perceptual capture of relevant histopathologic findings, and cognitive integration of identified features between 2 groups of residents, those who had and those who had not undergone their dermatopathology rotation. DESIGN: Residents read a case set of 20 virtual slides (10 depicting nodular and diffuse dermatitis and 10 depicting subepidermal vesicular dermatitis), using an in-house-developed interface. We recorded residents' reports of diagnostic findings, conjectured diagnostic hypotheses, and final (or differential) diagnosis for each case, and time stamped each interaction with the interface. We created search maps of residents' slide exploration strategy. RESULTS: No statistically significant differences were observed between the resident groups in the number of correctly or incorrectly reported diagnostic findings, but residents with dermatopathology training generated significantly more correct hypotheses (mean improvement of 88.5%) and correct diagnoses (70% of all correct diagnoses). CONCLUSIONS: Two types of slide exploration strategy were identified for both groups: (1) a focused and efficient search, observed when the final diagnosis was correct; and (2) a more dispersed, time-consuming strategy, observed when the final diagnosis was incorrect. This difference was statistically significant, and it suggests that initial interpretation of a slide may bias further slide exploration.

Mammographic images segmentation using texture descriptors.

Tissue classification in mammography can help the diagnosis of breast cancer by separating healthy tissue from lesions. We present herein the use of three texture descriptors for breast tissue segmentation purposes: the Sum Histogram, the Gray Level Co-Occurrence Matrix (GLCM) and the Local Binary Pattern (LBP). A modification of the LBP is also proposed for a better distinction of the tissues. In order to segment the image into its tissues, these descriptors are compared using a fidelity index and two clustering algorithms: k-Means and SOM (Self-Organizing Maps).

Clinical features of rhabdomyolysis after open and laparoscopic Roux-en-Y gastric bypass.

BACKGROUND: Rhabdomyolysis (RML) is caused by muscle injury, this may cause kidneys overload and lead to acute renal failure (ARF). The risk factors for RML in bariatric surgery (BS) are operative time (OT) >4 h and high BMI. The frequency of RML in BS varies from 12.9 to 37.8%. This study has the objective of describing the characteristics associated with RML and ARF in BS. METHODS: We studied retrospectively 114 patients submitted to BS. Criteria for RML were CPK level >950 IU/l (five times the normal value). The variables were BMI, OT, age, intraoperative hydration and diuresis, CPK, creatinine, arterial hypertension, peripheric vascular disease, diabetes, open and laparoscopic techniques--inclusion criteria: patients submitted to gastric bypass; exclusion: renal failure and statins use. RESULTS: RML incidence was 7%. The factors associated with RML in the bivariate analysis were hepatic steatosis, high BMI, high weight, higher excess weight, and prolonged OT. The risk factor for RML in the multivariate analysis was BMI > or = 50 kg/m2. When the OT was below 2 h the incidence of RML was zero, but this was not significant in the multivariate analysis. The factors associated with a higher risk of CPK elevation (multivariate analysis) were hypertension and open technique. CONCLUSION: BS is safe, with low incidence of RML/ARF. High BMI is associated with a higher risk of RML. Probably a longer OT is associated with a higher risk of RML not statistically demonstrated in this study. The factors associated with a higher risk of CPK elevation were hypertension and open technique.

Image segmentation of ovitraps for automatic counting of Aedes Aegypti eggs.

The Aedes Aegypti mosquito is the vector of the most difficult public health problems in tropical and semi-tropical world: the epidemic proliferation of dengue, a viral disease that can cause human beings death specially in its most dangerous form, dengue haemorrhagic fever. One of the most useful methods for mosquito detection and surveillance is the ovitraps: special traps to collect eggs of the mosquito. It is very important to count the number of Aedes Aegypti eggs present in ovitraps. This counting is usually performed in a manual, visual and non-automatic form. This work approaches the development of automatic methods to count the number of eggs in ovitraps images using image processing, particularly color segmentation and mathematical morphology-based non-linear filters.

Incidence of lower limbs deep vein thrombosis after open and laparoscopic gastric bypass: a prospective study.

BACKGROUND: Lower limbs deep vein thrombosis (DVT) and pulmonary embolism (PE) are major causes of morbidity and mortality and are even higher in bariatric patients. The longer operative time and higher immobility in these patients increase the DVT risk. Although deaths after bariatric surgery have been reported, there is no consensus regarding the prophylaxis of DVT. This study's objective is to determine the incidence of lower limbs DVT in patients submitted to Roux-en-Y-gastric bypass (RYGBP) under prophylaxis by enoxaparin. METHODS: Patients with body mass index (BMI) equal to or higher than 35 kg/m(2) who submitted to RYGBP by laparotomy or laparoscopy using 40 mg/day of enoxaparin for 15 days were recruited between October 2004 and August 2005. Individuals with previous DVT and heparin allergy were excluded. Patients were tested for DVT using color Doppler ultrasound performed before surgery and on the second and fifth weeks after surgery. RESULTS: The study population included 136 patients, with 126 concluding the protocol. There were 79% (100/126) of female patients aged 19 to 65 years old, with mean of 40 years SD = 10 and BMI between 35 and 61 kg/m(2), mean of 43 kg/m(2) (SD = 5). All patients who submitted to RYGBP were divided as 55% (69/126) by laparoscopy and 45% (57/126) by laparotomy. The incidence rate of lower limbs DVT was 0.79% (1/126). CONCLUSION: The low incidence rate of DVT found in our study suggests that obesity might not be a major risk factor for venous thromboembolism in patients submitted to RYGBP.

Rhabdomyolysis: diagnosis and treatment in bariatric surgery.

BACKGROUND: Rhabdomyolysis (RML) and subsequent acute renal failure can be serious problems following bariatric operations. Early diagnosis and treatment are important to avoid the complications of RML. METHODS: This review was achieved by searching the key words: Rhabdomyolysis, diagnosis, treatment and bariatric surgery. We included prospective, retrospective, case reports and review articles. RESULTS: RML diagnosis can be done by: signs and symptoms, physical evaluation, laboratory findings and imaging examinations. Muscle weakness, myalgia, decubitus ulcer, proteinuria and myoglobinuria are the more mentioned findings. Elevation of CPK levels is the most sensitive diagnostic evidence of RML. Treatment is geared toward preserving renal function by avoiding dehydration, hypovolemia, tubular obstruction, aciduria, and free radical release. Early recognition allows the administration of fluids, bicarbonate, and mannitol. CONCLUSION: Prophylactic measures and early diagnosis and treatment of rhabdomyolysis in bariatric surgery are imperative to prevent the potential fatal complications of this condition.

Laparoscopic gastric banding in the rat model as a means of videolaparoscopic training.

BACKGROUND: The development of laparoscopy in bariatric surgery has attracted a large number of surgeons. Learning this method for future clinical practice requires intensive training with inert tissues, simulators and experimental surgery in animals. Performing these procedures in small animals, with the same equipment used in humans, is feasible, allowing familiarization with and comprehension of the basic techniques. Wistar rats weighing 300-600 g were used. The animals were kept in standard laboratory conditions. A laparoscopic video-system, Veress needle, three ports, a 0 degree optic, a laparoscopic needle-holder, two 5-mm graspers, a 5-mm dissection clamp and a 5-mm scissors were used. An orogastric catheter with three 4-0 nylon sutures and one 6-0 nylon suture were also utilized. For the gastric band, we used a plastic device similar to the human gastric band. The present study describes a simple, inexpensive and reproducible technique for laparoscopic gastric banding in a rat model utilizing the same instruments developed for humans. The experimental rat model is more motivating than simulators, requires less space, and has easier maintenance compared with bigger animals, and consequently allows the use of more animals for teaching, training and application in many scientific studies.

Staplerless laparoscopic gastric bypass: a new option in bariatric surgery.

The staplerless Roux-en-Y gastric bypass (RYGBP) is a new option in bariatric surgery. The first to describe it was Himpens (2004) utilizing the LigaSure Atlas (LSA) in a series of 10 patients. The laparoscopic RYGBP is performed utilizing the LSA for the gastric and jejunal partition; after that, an imbricating running suture is performed to ensure stomach and bowel hermetic closure. All anastomoses are hand-sewn. Technical disadvantages are: learning curve; complications related to suture failure; possible thermal/electricity related injuries; longer operating time. Advantages are: stapler-associated bleeding, leaks, staple-line disruption, and fistulas are avoided; cost reduction. The staplerless RYGBP is complex; the surgeon involved requires expertise and ability. This technique will evolve and will be used by more surgeons. It is a new option for the surgeon preoccupied with costs, which is particularly important in developing countries.