Biomedical subjects

Aki Kido

Publications and source records attributed to Aki Kido.

11 recordsLinked to original sources

PubMed2006

Cine MR imaging of uterine peristalsis in patients with endometriosis.

Endometriosis is one of the most important causes of infertility; however the precise mechanism by which it affects female fertility is unclear. The objective of this study was to study the functional aspects of the uterus by evaluating uterine contractility in patients with endometrial cysts of the ovary. The study population was recruited from two institutes and consisted of 26 women (periovulatory (10), luteal (13), and menstrual phase (3); age range: 19-51 years) with untreated endometriosis; the control group consisted of 12 healthy women (age range: 22-41 years). Cine MR imaging obtained by a 1.5T magnet was visually evaluated at 12x faster than real speed, focusing on the presence of uterine peristalsis, the direction and frequency of peristalsis, and the presence of sustained uterine contractions. Uterine peristalsis was identifiable in 3/10, 3/13, and 3/3 of the endometriosis patients in each menstrual cycle, respectively, and in 11/12, 3/12, and 5/12 of their control subjects. Peristaltic detection rate and frequency were significantly less for the endometriosis group than for the controls in the periovulatory phase only (p<0.05). Sustained contractions were recognized in 19/36 control subjects and in 13/26 endometriosis patients, but the difference was not significant. Uterine peristalsis appears to be suppressed during the periovulatory phase in patients with endometriosis, which may have an adverse effect on sperm transport.

Adult↗

PubMed2006

Investigation of uterine peristalsis diurnal variation.

BACKGROUND: In women of reproductive age, wavelike movements of the subendometrial myometrium, which is called uterine peristalsis, is considered to be related with fertility and menstrual problems. This is because the direction and frequency of peristalsis is known to be different among menstrual cycle phases. However, nothing is known as regarding diurnal variations. This study was designed to evaluate for the presence of a diurnal variation in uterine peristalsis. MATERIALS AND METHODS: MR studies were performed on 12 volunteers of reproductive age using a 1.5-T magnet, four times per day (at 0800, 1300, 1800 and 2300 h) during three (periovulatory, luteal and menstrual) phases of one menstrual cycle. Sixty images were obtained by half-Fourier acquisition single-shot turbo spin echo every 2 s and displayed on cine mode. Semiautomated software was utilized to discern the presence of peristaltic waves, as well as peristaltic frequency and direction. The presence of sustained contractions was visually determined. RESULTS: There was no statistically significant difference during the daytime for frequency and direction of uterine peristalsis for all menstrual cycle phases. Nonetheless, peristaltic frequency and direction fluctuated during each cycle. Statistically significant peristaltic suppression was observed in association with sustained contractions during the periovulatory phase. CONCLUSIONS: A diurnal variation was not observed for uterine peristalsis. Sporadic changes in peristaltic frequency were observed and appear to be closely related to sustained uterine contractions.

Adult↗

PubMed2006

MR features of physiologic and benign conditions of the ovary.

In reproductive women, various physiologic conditions can cause morphologic changes of the ovary, resembling pathologic conditions. Benign ovarian diseases can also simulate malignancies. Magnetic resonance imaging (MRI) can play an important role in establishing accurate diagnosis. Functional cysts should not be confused with cystic neoplasms. Corpus luteum cysts typically have a thick wall and are occasionally hemorrhagic. Multicystic lesions that may mimic cystic neoplasms include hyperreactio luteinalis, ovarian hyperstimulation syndrome, and polycystic ovary syndrome. Recognition of clinical settings can help establish diagnosis. In endometrial cysts, MRI usually provides specific diagnosis; however, decidual change during pregnancy should not be confused with secondary neoplasm. Peritoneal inclusion cysts can be distinguished from cystic neoplasms by recognition of their characteristic configurations. Ovarian torsion and massive ovarian edema may mimic solid malignant tumors. Recognition of normal follicles and anatomic structures is useful in diagnosing these conditions. In pelvic inflammatory diseases, transfascial spread of the lesion should not be confused with invasive malignant tumors. Radiologic identification of abscess formation can be a diagnostic clue. Many benign tumors, including teratoma, Brenner tumor, and sex-cord stromal tumor, frequently show characteristic MRI features. Knowledge of MRI features of these conditions is essential in establishing accurate diagnosis and determining appropriate treatment.

Diagnosis, Differential↗

PubMed2005

Dysmenorrhea: evaluation with cine-mode-display MR imaging--initial experience.

PURPOSE: To prospectively evaluate uterine contractility during menstruation and its relation to primary dysmenorrhea by using magnetic resonance (MR) imaging with cine mode display. MATERIALS AND METHODS: The university ethics committee approved the study protocol, and all subjects gave written informed consent. Nineteen healthy women were examined during menstrual cycle days 1-3 by using a 1.5-T-magnet unit. Sixty serial half-Fourier rapid acquisition with relaxation enhancement MR images of the uterus were obtained every 3 seconds for 3 minutes and displayed in cine mode. MR images were analyzed in terms of thickness of the inner low-signal-intensity myometrial layer, presence of endometrial distortion, and uterine peristalsis detectability. Pain was assessed by using a four-point scale. For 56 MR imaging cases, the association between MR imaging findings and pain degree was examined with Spearman correlation and Mann-Whitney tests. MR imaging findings in the dysmenorrheic and eumenorrheic subject groups were compared by using Mann-Whitney and chi(2) tests. The area of the uterine myometrium in both groups was calculated for quantitative assessment of uterine contraction and was compared between the groups by using the Student t test. RESULTS: MR imaging findings revealed marked changes during cycle days 1-3. Thickness of the inner low-signal-intensity myometrial layer and endometrial distortion were significantly associated with pain degree (P < .001), while uterine peristalsis was undetectable when pain was severe or moderate. The area of the uterine myometrium significantly decreased during cycle days 1-3 in the dysmenorrheic group, as compared with that in the eumenorrheic group (P = .010). CONCLUSION: MR imaging features of the uterus on cycle days 1-3 correlated with pain degree. Cine-mode-display MR imaging is a potential tool for evaluating dysmenorrhea.

Adult↗

PubMed2005

A semiautomated technique for evaluation of uterine peristalsis.

PURPOSE: To evaluate the capability of a newly developed semiautomatic analysis technique for evaluation of uterine peristalsis in comparison with visual assessment. MATERIALS AND METHODS: Cine magnetic resonance (MR) images were obtained from 16 normal volunteers in periovulatory phase. Sixty-eight studies were evaluated by both visual evaluation and by a semiautomated computer assisted software. The software was developed by applying an automated contour tracking method and enables objective analysis of frequency, amplitude, velocity, and direction. Assessments were based on: 1) the recognition of peristalsis, 2) peristaltic direction and frequency, and 3) the way of recognizing peristaltic direction. The data obtained by both modalities were compared with those of previously reported ultrasound (US) findings. RESULTS: Uterine peristalsis was identified in all studies by both objective and visual analyses. There was no significant difference in the identification of peristalsis, recognition of peristaltic directions, or peristaltic frequency (P > 0.05). Data were well in accordance with those in US literature. Peristaltic direction was recognized either by configuration change in the endometrium or by conduction of low signal intensity in the subendometrial myometrium and there was statistically no difference. CONCLUSION: Evaluation of uterine peristalsis by the semiautomatic analysis accorded well with the results obtained visual assessments and previous US findings.

Adult↗

PubMed2005

Oral contraceptives and uterine peristalsis: evaluation with MRI.

PURPOSE: To evaluate the effects of oral contraceptives (OCs) on uterine contractility using cine MRI, and correlate the kinematic findings with the static findings. MATERIALS AND METHODS: Healthy female volunteers of reproductive age (23 taking OCs, and 15 not) were evaluated at mid-cycle. MR images were obtained with a 1.5T magnet, with 60 serial images taken every three seconds by half-Fourier acquisition single-shot turbo spin echo (HASTE) to be displayed in cine mode. Assessments were based on the 1) detectability of uterine peristalsis in cine mode, 2) peristaltic frequency and direction, 3) thickness of the endometrium, myometrium, and junctional zone (JZ) on T2-weighted images (T2WIs), and 4) intensity of the myometrium and cervical mucus on T2WIs and T1-weighted images (T1WIs), respectively. RESULTS: Uterine peristalsis was markedly decreased in the OC users. The endometrium and JZ were significantly thinner, and the myometrium was thicker in the OC users compared to controls. The signal intensity of the myometrium and cervical mucus was significantly higher in the OC users than in controls. CONCLUSION: OCs markedly suppressed uterine peristalsis at mid-cycle, and the uterus displayed a globular configuration with a thin JZ that may be related to decreased uterine peristalsis in OC users.

Adult↗

PubMed2004

Uterine peristalsis: comparison of transvaginal ultrasound and two different sequences of cine MR imaging.

PURPOSE: To compare uterine peristalsis as seen on two different magnetic resonance (MR) imaging sequences and transvaginal ultrasound (TVUS), so as to better determine the best method for evaluating uterine peristalsis. MATERIALS AND METHODS: Eleven women in the periovulatory phase of the menstrual cycle underwent TVUS and cine MR imaging within a time period of three hours. Findings on cine MR images obtained with a serial 60 half-Fourier acquisition single-shot turbo spin-echo (HASTE) sequence and a 300 true fast imaging with steady-state precession (FISP) sequence were compared with TVUS. RESULTS: The image quality of the HASTE technique was the best among the three methods, followed by TVUS, and then true FISP technique (P < 0.001). Uterine peristalsis was detected in 100% of subjects using HASTE, 82% with True FISP, and 100% with TVUS. With HASTE technique, true FISP, and TVUS, respectively, endometrial stripping movement was identified in 100%, 82%, and 100%; direction was identified in 100%, 45% (P = 0.014), and 73%; and wave conduction toward the outer myometrium was identified in 55%, 9% (P = 0.025), and 0% (P = 0.014). CONCLUSION: Cine MR imaging by HASTE technique with a time resolution of two seconds best delineated uterine peristalsis compared to that by true FISP technique or with TVUS.

Adult↗

PubMed2003

Kinematics of the uterus: cine mode MR imaging.

Cine mode magnetic resonance (MR) imaging has allowed evaluation of kinematics of the pelvis. Visualization of dynamic changes under strain facilitates evaluation of prolapses and adhesions between organs. The uterus, an organ of smooth muscle, has an inherent contractility that characterizes it as different from other visceral organs. This sustained contraction has occasionally been shown on static images as a finding masquerading as a leiomyoma or as adenomyosis. Cine mode MR imaging clearly shows the configuration of the myometrium during these dynamic changes, as well as its signal intensity during contractions. Uterine peristalsis, the subtle and rhythmic contractions of the inner myometrium, is also clearly identifiable on cine mode images as a wavy movement of the endometrium and/or inner myometrium. The direction and frequency of uterine peristalsis are different in each of the menstrual cycle phases and are thought to have important roles in uterine function, such as in fertility and menstrual blood discharge. Elucidation of these kinematics of the uterus will help in the evaluation of static MR images and study of the physiology of the uterus. Cine MR imaging is a novel technique for diagnosis and evaluation of the pelvic organs, especially the uterus.

Adult↗

PubMed2003

Uterine arterial embolization for the treatment of diffuse leiomyomatosis.

Diffuse leiomyomatosis of the uterus is an extremely rare condition and presents as a diffuse involvement of the myometrium by numerous leiomyomata. Despite patients being in only the third or fourth decades of life, all previously reported patients with this condition have undergone hysterectomy because myomectomy is impossible for this condition. Uterine arterial embolization (UAE) successfully reduced the uterine volume of diffuse leiomyomatosis without major complications in the case presented herein, and the symptoms improved remarkably. Enhanced magnetic resonance imaging after intravenous injection of gadolinium demonstrated global infarction of the vast majority of nodules.

Adult↗

PubMedDate not supplied

Retained products of conception masquerading as acquired arteriovenous malformation.

This case documents a seldom-described event of retained products of conception masquerading as an acquired arteriovenous malformation (AVM) of the uterus. The patient presented with sudden onset of heavy vaginal bleeding 6 weeks after artificial abortion. Ultrasonography and magnetic resonance imaging revealed a diffuse intramural lesion predominantly consisting of prominent vessels, which raised suspicion of an AVM. Hysterectomy revealed retained products of placenta that were necrotic and encroached into thin myometrium.

Adult↗

PubMedDate not supplied

Diffusely enlarged uterus: evaluation with MR imaging.

Diffuse uterine enlargement is a common clinical finding. Because this abnormality can represent a physiologic manifestation, benign tumor, or malignancy, the diagnostic dilemma of a diffusely enlarged uterus can be challenging. Clinical findings can provide valuable information in regard to physiologic effects, pregnancy-related changes, and hormonal causes. Cytologic examination is essential for identification of cervical and endometrial malignancies. However, since preoperative histologic examination of myometrial lesions is not possible, preoperative distinction between benign and malignant conditions is frequently difficult. Imaging thus plays an important role in evaluation of myometrial lesions. In particular, magnetic resonance (MR) imaging allows specific diagnosis of several different lesions. Signal voids and prominent vessels at MR imaging are characteristic of vascular lesions. Adenomyosis and leiomyomas can be distinguished from other lesions with MR imaging, although a variety of unusual manifestations can be seen. MR imaging findings that allow distinction between leiomyoma and leiomyosarcoma have yet to be clearly established; however, invasion, hemorrhagic necrosis, or rapid growth is suggestive of malignancy. Endometrial stromal sarcoma tends to have distinct MR imaging features that allow differentiation from benign lesions.

Adult↗