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1.
J Ultrasound Med ; 43(3): 553-560, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38088498

ABSTRACT

PURPOSE: This study aims to investigate and compare quantitative factors of the cesarean scar defect (CSD) in symptomatic patients with and without uterine adenomyosis. METHOD: This study was conducted as a case-control study. Patients who met the inclusion criteria were divided into two groups: with adenomyosis (case) and without adenomyosis (control). The demographic data, medical history, and sonohysterography findings were extracted from the patient's documents and archived images. RESULT: During 2 years, 310 symptomatic women with a history of previous cesarean section underwent sonohysterography. Among them, 204 patients met the inclusion criteria. The most common chief complaints were post-menstrual bleeding (34.3%) and prolonged bleeding (27%). Cesarean scar depth and width significantly differed between these two groups, and patients with underlying adenomyosis had significantly larger defects (P-value of .009 and .005, respectively). Mean RMT/AMT ratio was 31.83% in the case group and 42.88% in the control group. In our study, RMT/AMT ratios were significantly lower in the case group (P-value of .001). In addition, we performed analysis on a subgroup of patients with one prior cesarean section. Similar results were achieved with a lower RMT/AMT ratio in case group (mean of 31.20% in case group and 46.47% in control group; P-value of .000). CONCLUSION: Our study showed a strong association between the presence of adenomyosis and larger clinically more significant CSDs. To establish a causative relationship, we suggest a prospective cohort study to follow up the patients and compare the evolution of CSD in patients with and without adenomyosis.


Subject(s)
Adenomyosis , Cicatrix , Humans , Female , Pregnancy , Adenomyosis/complications , Cesarean Section/adverse effects , Case-Control Studies , Prospective Studies
2.
Curr Pharm Des ; 24(37): 4474-4483, 2018.
Article in English | MEDLINE | ID: mdl-30582471

ABSTRACT

BACKGROUND: Keratoconus is recognized by asymmetrical thinning and bulging of the cornea, resulting in distortion in the surface of the cornea. Keratoconus also alters the biomechanical properties of the cornea, which can be an indicator of the healthy and keratoconus eyes. This study was aimed at employing a combination of clinical data, finite element method (FEM), and artificial neural network (ANN) to establish a novel biomechanical- based diagnostic method for the keratoconus eyes. METHODS: To do that, the clinical-biomechanical parameters of 40 healthy and 40 keratoconus eyes were obtained via the Pentacam and non-contact tonometer (Corvis ST, Oculus Optikgeräte, Wetzlar, Germany) devices. Intraocular pressure (IOP) was measured using a Goldmann applanation tonometer as well as Corvis. According to the geometry of the cornea, the FE model of each cornea was made and the same boundary and loading conditions were applied not only to confirm the FE model in terms of the biomechanical parameters but also to calculate the amount of von Mises stress in the apex of the cornea. The clinical-biomechanical data of the Corvis along with the von Mises stresses were then incorporated into the ANN algorithm to distinguish the healthy and keratoconus corneas on a basis of the resulted von Mises stresses. The proposed programming code, according to the input data from the Corvis, enabled to predict whether the cornea is keratoconus or not. Finally, to verify the results of the proposed method, 155 individuals were examined. RESULTS: The clinical and biomechanical results of the Corvis revealed that the healthy corneas have a higher thickness compared to the keratoconus ones. No significant differences were observed among the IOPs, 1st applanation length, and pick distance in the highest concavity. The 2nd applanation length and radius in the highest concavity of the healthy cornea were higher than the keratoconus ones. Conversely, the 1st and 2nd applanation velocities and deformation amplitudes of the keratoconus corneas were higher than the healthy ones. The FE results also showed higher stresses for the healthy corneas compared to the keratoconus ones. The ANN was also well verified since it demonstrated more than 95.5% accuracy on diagnosing the keratoconus eyes. CONCLUSION: These findings have implications not only for identifying the keratoconus corneas as an important clinical and surgical tool for eye care professionals but also for providing both a quantitative and an accurate approach to the problem of understanding the biomechanical nature of keratoconus.


Subject(s)
Finite Element Analysis , Keratoconus/diagnosis , Neural Networks, Computer , Algorithms , Biomechanical Phenomena , Humans , Keratoconus/physiopathology , Prospective Studies , Stress, Mechanical
3.
Photoacoustics ; 7: 27-35, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28702357

ABSTRACT

In the application of photoacoustic human infant brain imaging, debubbled ultrasound gel or water is commonly used as a couplant for ultrasonic transducers due to their acoustic properties. The main challenge in using such a couplant is its discomfort for the patient. In this study, we explore the feasibility of a semi-dry coupling configuration to be used in photoacoustic computed tomography (PACT) systems. The coupling system includes an inflatable container consisting of a thin layer of Aqualene with ultrasound gel or water inside of it. Finite element method (FEM) is used for static and dynamic structural analysis of the proposed configuration to be used in PACT for infant brain imaging. The outcome of the analysis is an optimum thickness of Aqualene in order to meet the weight tolerance requirement with the least attenuation and best impedance match to recommend for an experimental setting.

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