Image-derived Metrics Quantifying Hemodynamic Instability Predicted Growth of Unruptured Intracranial Aneurysms

Background

While image-derived predictors of intracranial aneurysm (IA) rupture have been well-explored, current understanding of IA growth is limited. Pulsatility index (PI) and wall shear stress pulsatility index (WSSPI) are important metrics measuring temporal hemodynamic instability. However, they have not been investigated in IA growth research. The present study seeks to verify reliable predictors of IA growth with comparative analyses of several important morphological and hemodynamic metrics between stable and growing cases among a group of unruptured IAs.

Methods

Using 3D images, vascular models of 16 stable and 20 growing cases were constructed and verified using Geodesic techniques. With an overall mean follow-up period of 25 months, cases exhibiting a 10% or higher increase in diameter were considered growing. Patient-specific, pulsatile simulations were performed, and hemodynamic calculations were computed at 5 important regions of each aneurysm (inflow artery, aneurysm neck, body, dome, and outflow artery). Index values were compared between growing and stable IAs using ANCOVA controlling for aneurysm diameter. Stepwise multiple logistic regression and ROC analyses were conducted to investigate predictive models of IA growth.

Results

Compared to stable IAs, growing IAs exhibited significantly higher intrasaccular PI, intrasaccular WSSPI, intrasaccular spatial flow rate deviation, and intrasaccular spatial wall shear stress (WSS) deviation. Stepwise logistic regression analysis revealed a significant predictive model involving PI at aneurysm body, WSSPI at inflow artery, and WSSPI at aneurysm body.

Conclusions

Our results showed that high degree of hemodynamic variations within IAs is linked to growth, even after controlling for morphological parameters. Further, evaluation of PI in conjunction with WSSPI yielded a highly accurate predictive model of IA growth. Upon validation in future cohorts, these metrics may aid in early identification of IA growth and current understanding of IA remodeling mechanism.

Impact of cerebral aneurysm size on distal intracranial hemodynamics and changes following flow diversion

BACKGROUND

The impact of cerebral aneurysm size on distal intracranial hemodynamics such as arterial pressure and Pulsatility Index is not completely understood, either before or after flow diversion.

OBJECTIVE

The aim of the study is to assess the impact of aneurysm size on distal Pulsatility Index and pressure before and after flow diversion.

METHODS

From December 2015, prospective measurement of middle cerebral artery pressure and Pulsatility Index was performed in consecutive patients with unruptured cerebral aneurysms in the cavernous to communicating segments of the internal carotid artery, which were treated with single flow diversion. Pressure and Pulsatility Index were recorded at the M1-segment ipsilateral to the cerebral aneurysm. Ratio of middle cerebral artery to radial arterial pressure (pressure ratio) was calculated to control for variations in systemic blood pressure. Correlations between aneurysm size and pressure ratio and Pulsatility Index were assessed before and after treatment.

RESULTS

A total of 28 aneurysms were treated. The mean aneurysm size was 7.2 mm. Aneurysm size correlated linearly with systolic pressure ratio (1% pressure ratio increase per mm aneurysm size increase, P = 0.002, r² = 0.33), mean pressure ratio (0.6% per mm, P = 0.03, r² = 0.17) and Pulsatility Index (5% Pulsatility Index increase per mm, P = 0.003, r² = 0.43). After flow diversion, aneurysm size preserved a linear correlation with the systolic pressure ratio (1% per mm, P = 0.004, r²  =  0.28), but not with the mean pressure ratio (0.4% per mm, P = 0.15, r² < 0.1) or Pulsatility Index (0.3% per mm, P = 0.78, r² < 0.1).

CONCLUSION

Aneurysm size affects distal hemodynamics: patients with larger aneurysms have increased systolic and mean pressure ratio, and increased Pulsatility Index. After flow diversion, mean pressure ratio and Pulsatility Index no longer associate with the aneurysm size, suggesting an effect of the flow diversion also on distal intracranial hemodynamics.

Is There a Role for Color Doppler Ultrasonography in Acute Cholecystitis?

OBJECTIVE

The aim of this study was to evaluate the utility of the Pulsatility Index (PI) of the right hepatic artery, measured by color Doppler sonography, in the diagnosis of acute cholecystitis.

METHODS

Seventy-five subjects were included in this study and divided into three groups, each consisting of 25 subjects: the cholecystitis group, the asymptomatic cholelithiasis group, and normal controls. Patients with acute cholecystitis fulfilled all the diagnostic criteria as stated in the latest Tokyo Guidelines. In all patients, the right hepatic artery was detected by color Doppler ultrasound and the PI was measured.

RESULTS

Patients with acute cholecystitis were found to have significantly higher PI values compared to both normal controls and cholelithiasis patients. Regression analysis revealed a significant positive correlation between the PI and the cholecystitis outcome.

CONCLUSION

Measurement of PI by color Doppler ultrasound represents a useful aid in the diagnostic process of acute cholecystitis. More studies are needed before this method is incorporated in the relevant guidelines.

Transcranial Doppler Evaluation of the Cerebral Vasculature in Women Patients who Have Migraine with Aura

BACKGROUND

Previous studies suggest that increased cerebrovascular reactivity might be a feature of patients who have migraine with aura (MwA). The correlation between the clinical presentation of migraine with aura and transcranial Doppler parameters remains unclear.

OBJECTIVE

The main aim of this study was to explore cerebral blood flow, vascular resistance, and cerebrovascular reactivity in women MwA. Also, the relationships between hemodynamic conditions and aura characteristics are examined.

DESIGN

Cross-sectional study.

SETTING

Headache Center, Neurology Clinic, Clinical Center of Serbia.

SUBJECTS

Fifty-four women MwA and 49 healthy controls (HCs).

METHODS

Transcranial Doppler sonography examination was used to determine blood flow mean velocity (MV) and pulsatility index (PI), as well as breath-holding index (BHI), in 15 arterial segments comprising the circle of Willis.

RESULTS

A total of 54 women MwA and 49 HCs were studied. The PIs of all segments of the left and right middle cerebral arteries and the left and right anterior cerebral arteries were significantly higher in MwA with regards to HCs. Also, both the left and right BHIs were significantly higher in MwA than HCs. In addition, MVs of the right vertebral artery and the first segment of the basilar artery were significantly lower in MwA than HCs. Longer duration of migraine aura showed a weak negative correlation with the PI of the left posterior cerebral artery.

CONCLUSIONS

Our findings suggest increased vessel pulsatility, abnormal cerebrovascular reactivity, and decreased cerebral blood flow velocity in several arterial segments of the Willis circle in women MwA.

MiRNAs Regulating Oxidative Stress: A Correlation with Doppler Sonography of Uteroplacental Complex and Clinical State Assessments of Newborns in Fetal Growth Restriction

Overproduction of reactive oxygen species (ROS) and, as a result, uncontrolled oxidative stress (OS) can play a central role in disorders of fetal hemodynamics and subsequent development of adverse perinatal outcomes in newborns with fetal growth restriction (FGR). Given the epigenetic nature of such disorders, the aim of our study was to evaluate the expression of miRNAs associated with OS and endothelial dysfunction (miR-27a-3p, miR-30b-5p, miR-125b-5p, miR-221-3p, miR-451a and miR-574-3p) in umbilical cord blood using real-time quantitative RT-PCR. ΜiRNA expression was evaluated in patients with FGR delivery before (n = 9 pregnant) and after 34 weeks of gestation (n = 13 pregnant), and the control groups corresponding to the main groups by gestational age (13 pregnant women in each group, respectively). A significant increase in miR-451a expression was detected in late-onset FGR and correlations with fetoplacental and cerebral circulation were established (increase of resistance in the umbilical artery (pulsatility index, PI UA (umbilical artery): r = −0.59, p = 0.001) and a decrease in cerebral blood flow (CPR: r = 0.48, p = 0.009)). The change in miR-125b-5p expression in the placenta is associated with reduced Doppler of cerebral hemodynamics (CPR: r = 0.73, p = 0.003; PI MCA (middle cerebral artery): r = 0.79, p = 0.0007), and newborn weight (r = 0.56, p = 0.04) in early-onset FGR. In addition, significant changes in miR-125b-5p and miR-451a expression in umbilical cord blood plasma were found in newborns with neonatal respiratory distress syndrome (NRDS) (in early-onset FGR) and very low birth weight (VLBW) (in late-onset FGR). A number of key signaling pathways have been identified in which the regulation of the studied miRNAs is involved, including angiogenesis, neurotrophin signaling pathway and oxidative stress response. In general, our study showed that changes of the redox homeostasis in the mother-placenta-fetus system in FGR and subsequent perinatal outcomes may be due to differential expression of oxidative stress-associated miRNAs.

Association Between Fetal Middle Cerebral Artery and Umbilical Artery Doppler Ratio with Fetal Distress in 38-40 Weeks of Gestation

BACKGROUND AND OBJECTIVE

Knowing the factors affecting fetal distress is of particular importance in improving prognosis in newborns. The study aimed to determine the relationship between fetal middle cerebral artery pulsatility indexes and umbilical artery Doppler ratio with fetal distress at 38-40 weeks of gestation.

MATERIALS AND METHODS

In this prospective cohort, 181 consecutive pregnant women with 38-40 weeks of gestational age were selected by a non-random convenience sampling method from January 2016 to January 2017. Women with labor pain and embryos with chromosomal and structural disorder were excluded. Color Doppler sonography was done for all of them, and the association of this ratio with fetal distress consequently was assessed as well.

RESULTS

In this study, abnormal amniotic fluid index (AFI) (1.1%), low birth weight (< 2500 g) (5.5%), emergency cesarean (11.6%), neonatal intensive care unit (NICU) admission (12.2%), low 5th minute Apgar (< 7) (0.6%), abnormal fetal monitoring (10.5%), fetal distress (11.6%), meconium aspiration syndrome (10.5%), and respiratory distress (3.9%) were present. The mean cerebroplacental ratio was 1.9. There was a significant association between low fetal middle cerebral artery pulsatility index and umbilical artery Doppler ratio with fetal distress, abnormal monitoring, and urgent cesarean (P = 0.006). The cutoff 1.94 led to sensitivity, specificity, positive predictive value, and negative predictive value of 80.95, 50, 17.5, and 95.2%, respectively.

CONCLUSION

It may be concluded that in our study a cutoff for fetal middle cerebral artery to umbilical artery ratio of 1.94 at 38 weeks was considered statistically significant in predicting fetal distress at 38-40 weeks. However, further studies with larger sample size and multi-center sampling would develop more definite results for wider application.

Tadalafil for Endometrial Growth in Clomiphene Citrate stimulated cycles in an IUI programma: A pilot study

AIM OF THE STUDY

The objective of this study was to assess the impact of tadalafil on endometrial growth, the uterine artery pulsatility index (PI) and the uterine artery resistance index (RI) in patients under clomiphene ovarian stimulation for intrauterine insemination (IUI).

METHODS

This randomized crossover study included 30 patients with a normal endometrium over 53 cycles, and 46 of those cycles in 23 patients were included in the analysis. In group A the patients were under 100 mg clomiphene daily for five days (2-6) and 5 mg tadalafil daily for 7 days (4-10). For Group B (control) the patients only received clomiphene. Measurements of the endometrium, PI, RI and estradiol determinations were taken on cycle days 4, 8 and 10.

RESULTS

We observed a better endometrial growth in Group A compared to Group B: 7.5 ± 2.1 mm vs 5.5 ± 1.2 mm, P < 0.0002 and 8.9 ± 1.8 mm vs 6.3 ± 1.8 mm, P < 0.0002 on days 8 and 10, respectively. Additionally, a progressive decrease in the RI was observed in Group A but not in Group B from day 8 (0.77 ± 0.15 vs 0.85 ± 0.18, P = 0.059) to day 10 (0.74 ± 0.20 vs 0.87 ± 0.14, P < 0.017). However, no differences were observed in PI or serum estradiol between Group A and Group B.

CONCLUSION

The use of tadalafil improved endometrial growth in patients under clomiphene ovarian stimulation with no significant effect on the uterine artery Pulsatility Index and serum estradiol.

Effects of Cabergoline administration on uterine perfusion in women with polycystic ovary syndrome

Objectives: The aim of this study was to determine the effects of Cabergoline administration on uterine blood flow in women suffering from polycystic ovary syndrome (PCOS).

Methods: This study is a randomized, controlled, triple-blind trial which is tested on 40 women who were randomly divided into two groups of 20 people and using a randomized block design during which the subjects were assessed and included. They were suffering from polycystic ovarian syndrome. Inclusion criteria were classically defined PCOS criteria including: oligomenorrhea or amenorrhea, clinical or Laboratory findings based on increase in blood level androgen (testosterone) and ultrasound confirmation of PCOS. Exclusion criteria were Pregnancy, lactation, Dopamine Agonist Therapy. After selection of intervention and placebo groups, primary control Doppler ultrasound was done for both groups. Then a weekly dose of Cabergoline 0.5 mg was administered to intervention group for duration of 12 weeks. Placebo group were administered placebo in the same fashion. At the end of 12 weeks, Doppler ultrasound was performed and the results were recorded in the check lists.

Results: No significant difference was noticed in both groups with respect to their age, employment, level of education, type of infertility, duration of marriage, and results of RI and PI before intervention. Later PCOS patients under the treatment of Cabergoline showed a significant increase in uterine blood flow Pulsatility Index (PI) before 2.65±0.52 and after 1.98±0.52 and RI before 0.85 and after intervention 0.77), yet no significant difference were found in PCOS patient under the treatment of placebo.

Conclusion: PCOS patients were shown to have more resistance in uterine blood flow than healthy people; however, Cabergoline administration proved to increase uterine blood perfusion and regulate menstruation cycle.