Surgical Outcomes and Complications of Laparoscopic Hysterectomy for Endometriosis: a multicentric cohort study

STUDY OBJECTIVE

To investigate the postoperative morbidity of laparoscopic hysterectomy (LH) for endometriosis/adenomyosis in terms of operative outcomes and complications.

DESIGN

Retrospective multicentric cohort study.

SETTING

Eight European minimally invasive referral centers.

PATIENTS

Data from 995 patients with pathologically confirmed endometriosis and/or adenomyosis who underwent LH without concomitant urological and/or gastroenterological procedures from January 2010 to December 2020.

INTERVENTIONS

Total laparoscopic hysterectomy.

MEASUREMENTS AND MAIN RESULTS

Demographic patients' characteristics, surgical outcomes, and intraoperative and postoperative complications were evaluated. We considered major postoperative surgical-related complications any grade 2 or more events (Clavien-Dindo score) that occurred within 30 days from surgery. Univariate analysis and multivariable models fit with logistic regression were used to estimate the adjusted odds ratio (OR) and corresponding 95% CI for major complications. Median age at surgery was 44 years (28-54) and about half of them (505, 50.7%) were on medical treatment (estro-progestins, progestin or GnRh-analogues) at the time of surgery. In association with LH, posterior adhesiolysis was performed in 387 (38,9%) cases and deep nodule resection in 302 (30,0%). Intraoperative complications occurred in 3% of the patients and major postoperative complications were registered in 93 (9.3%). The multivariable analysis showed an inverse correlation between the occurrence of Clavien-Dindo >2 complications and age (OR 0.94, 95%CI 0.90-0.99), while previous surgery for endometriosis (OR 1.62, 95%CI 1.01-2.60) and intraoperative complications (OR 6.49, 95%CI 2.65-16.87) were found as predictors of major events. Medical treatment at the time of surgery has emerged as a protective factor (OR 0.50, 95%CI 0.31-0.81).

CONCLUSION

LH for endometriosis/adenomyosis is associated with non-negligible morbidity. Knowing the factors associated with higher risks of complications might be used for risk stratification and could help clinicians during preoperative counseling. The administration of estro-progestin or progesterone preoperatively might reduce the risks of postoperative complications following surgery.

Ultrasound-guided needle biopsy for preoperative assessment of uterine fibroids: Our experience and a review of the literature

Leiomyomas are the most common uterine benign tumor, and their malignant counterpart leiomyosarcomas are extremely rare. Despite this, a preoperative diagnosis could be useful for safe surgical minimally invasive management. At present, some clinical and ultrasound findings help recognizing lesions at risk of malignancy. We tried to implement a technique for the preoperative diagnosis for lesions at risk performing ultrasound-guided biopsies of suspected lesions in ten patients. Among them, one case was diagnosed as malignant by the needle biopsy. All patients underwent surgery for myomectomy or hysterectomy, and the histology was confirmed in all cases. No complications occurred. The review of the literature shows other similar experiences of preoperative biopsy of uterine lesions, showing good results for the differential diagnosis between uterine sarcoma and leiomyoma. In our experience, despite the small number of patients enrolled, this technique is safe and effective to plan minimally invasive surgery of uterine fibroids.

Diagnosis and treatment of uncommon ileal endometriosis: a case report and literature review

Endometriosis is defined as the presence of endometrial tissue outside the uterine cavity. It is a common finding in premenopausal women and commonly affects the gastrointestinal tract, especially the rectosigmoid tract. Small bowel involvement is rare and usually asymptomatic making diagnosis difficult. Here we report an uncommon case of exophytic ileal endometriosis surgically treated. Detailed pre-operative counselling on the risk of ileal surgery should always be considered in all cases with endometriosis requiring surgery. We also present a review of the literature regarding the clinical presentation, diagnosis, and treatment of this challenging condition.

Evaluation of Bowel Function After Surgical Treatment for Intestinal Endometriosis: A Prospective Study

BACKGROUND

Defecation symptoms related to intestinal deep infiltrative endometriosis are caused by anatomical and functional disorders and are probably linked to the course of the disease and surgical treatment.

OBJECTIVE

The primary aim of this study was to assess bowel function before and after intestinal deep infiltrative endometriosis surgery. Secondarily, we sought to correlate defecatory symptoms with preoperative risk factors.

DESIGN/SETTINGS

This is a single-center prospective cohort study, using the low anterior resection syndrome score to evaluate bowel function 4 weeks before, as well as at 6 months and 1 year after surgery. The Wilcoxon signed-rank test and logistic multiple regression analyses were performed to compare preoperative and postoperative scores. The level of significance was set at <0.05 for all comparisons.

PATIENTS

Thirty-seven adult female patients who underwent intestinal resection for deep infiltrative endometriosis between 2015 and 2017 were included.

MAIN OUTCOME MEASURES

The primary outcome was bowel function appraisement in deep infiltrative endometriosis intestinal surgery.

RESULTS

During the preoperative evaluation, 48.6% of patients reported low anterior resection syndrome score ≥21. This group presented a mean score of 17.9 ± 13.7, with a median of 20 and a range of 5 to 30. After 1 year, the mean score was decreased to 9.6 ± 11.1, with a median of 4 and a range of 0 to 22. A significant difference was detected when comparing the post- and preoperative scores (p = 0.0006). Improvements in defecatory symptoms such as reduced fecal incontinence for flatus (p = 0.004) and liquid stools (p = 0.014) were also reported. The clustering of stools (p = 0.005) and fecal urgency (p = 0.001) also improved 1 year after surgery. The preoperative multiple logistic regression showed that dyschezia was the only independent variable associated with bowel symptoms.

LIMITATIONS

This is a well-documented prospective study, but the data presented have a relatively small population.

CONCLUSIONS

This study provides evidence that intestinal deep infiltrative endometriosis surgery improves bowel function and has a positive impact on evacuation symptoms. See Video Abstract at http://links.lww.com/DCR/B534.

EVALUACIN DE LA FUNCIN INTESTINAL DESPUS DEL TRATAMIENTO QUIRRGICO PARA LA ENDOMETRIOSIS INTESTINAL UN ESTUDIO PROSPECTIVO

ANTECEDENTES:Se considera que los síntomas defecatorios relacionados con la endometriosis intestinal infiltrativa profunda, son causados por trastornos anatómicos y funcionales, y probablemente estén relacionados con el curso de la enfermedad y tratamiento quirúrgico.OBJETIVO:El objetivo principal fue evaluar la función intestinal antes y después de la cirugía por endometriosis intestinal infiltrativa profunda. En segundo lugar, correlacionar los síntomas defecatorios con los factores de riesgo preoperatorios.DISEÑO / AJUSTES:Es un estudio de cohorte prospectivo de un solo centro, utilizando la puntuación del síndrome de resección anterior baja (LARS Score) para evaluar la función intestinal 4 semanas antes, 6 meses y un año después de la cirugía. Se realizaron pruebas de rango firmado de Wilcoxon y análisis de regresión logística múltiple para comparar puntuaciones preoperatorias y postoperatorias. Para todas las comparaciones, el nivel de significancia se estableció en <0.05.ENTORNO CLINICO:Se incluyeron 37 mujeres adultas sometidas a resección intestinal por endometriosis infiltrativa profunda entre 2015 y 2017.PRINCIPALES MEDIDAS DE VALORACION:El resultado principal, fue la evaluación de la función intestinal en cirugía de endometriosis infiltrativa profunda intestinal.RESULTADOS:Durante la evaluación preoperatoria, el 48,6% de los pacientes reportaron Síndrome de Resección Anterior Baja ≥ 21. Este grupo presentó una puntuación media de 17,9 ± 13,7, con una mediana de 20 y un rango de 5 a 30. Después de un año, la puntuación media se redujo a 9,6 ± 11,1, con una mediana de 4 y un rango de 0 a 22 Se detectó una diferencia significativa al comparar las puntuaciones postoperatorias y preoperatorias (p = 0,0006). Se informó de mejoras en los síntomas defecatorios como la reducción de la incontinencia fecal por flatos (p = 0,004) y heces líquidas (p = 0,014). La agrupación de heces (p = 0,005) y la urgencia fecal (p = 0,001) presentaron mejoría a un año después de la cirugía. La regresión logística múltiple preoperatoria mostró que la disquecia fue la única variable independiente asociada con los síntomas intestinales.LIMITACIONES:A pesar de que es un estudio prospectivo bien documentado, los datos presentados son de una población relativamente pequeña.CONCLUSIONES:El estudio proporciona evidencia de que la cirugía intestinal por endometriosis infiltrativa profunda, mejora la función intestinal y tiene un impacto positivo en los síntomas de evacuación. Consulte Video Resumen en http://links.lww.com/DCR/B534.

Slotted E-Shaped Meta-Material Decoupling Slab for Densely Packed MIMO Antenna Arrays

In contemporary wireless communication systems, the multiple-input and multiple-output systems are extensively utilized due to their enhanced spectral efficiency and diversity. Densely packed antenna arrays play an important role in such systems to enhance their spatial diversity, array gain, and beam scanning capabilities. In this article, a slotted meta-material decoupling slab (S-MTM-DS) with dual reflexes slotted E-shapes and an inductive stub is proposed. Its function was validated when located between two microstrip patch antenna elements to reduce the inter-element spacing, the mutual coupling, the return losses, and manufacturing costs due to size reduction. A prototype is simply fabricated in a volume of 67.41 × 33.49 × 1.6 mm³ and frequency-span measured from 8.4:11 GHz. At 9.4 GHz frequency, the spaces between the transmitting elements are decreased to 0.57 of the free space wavelength. When the proposed isolation S-MTM-DS is applied, the average isolation among them is measured to be −36 dB, the operational bandwidth is enhanced to be 1.512 GHz, the fractional bandwidth improved to be 16.04%, and the return losses are decreased to be −26.5 dB at 9.4 GHz center frequency. Consequently, the proposed design has the potential to be implemented simply in wireless contemporary communication schemes.

High-Resolution and Large-Detection-Range Virtual Antenna Array for Automotive Radar Applications

Collision avoidance and autonomous control of vehicles have become essential needs for providing a high-quality and safe life. This paper introduces a new generic scheme for a virtual antenna array (VAA) and its application in a train collision-avoidance system (TCAS). The proposed TCAS shall have the capability of identifying the range and angle of an object in front of a moving train and provide the required alerts. Thereby, a new virtual array distribution for both the transmitting and the receiving antenna arrays is introduced to get a long-range object detection and high-resolution multi-input multi-output (MIMO) system. This can be accomplished because the VAA radiation pattern is the multiplication of the radiation patterns for both the transmitting and receiving antenna arrays, which is different than each one of them alone. In this work, the VAA is utilized in radar systems in which the radar range depends on the multiplication of the gain of the transmitting and receiving antennas. So, we introduce a new scheme for the general design of VAA-based radars. A prototype for the antenna system was fixed on a of Texas Instruments platform for the cascading radar. One of the main problems of the VAA is the loss of radiated power in undesired directions, which affects the maximum detection range in beamforming systems and degrades the diversity gain in MIMO applications. These issues have been solved by the introduction of the practical implementation of a proposed high-gain, low side lobe level VAA system for automotive radar that is based on the integration of four AWR1243 RF chips operating in a frequency range of 76 GHz to 81 GHz. It was implemented using low-power 45 nm (TI) RFCMOS technology. The measured gain of the realized VAA was 47.2 dBi, which was 1.815 times higher than that of the Texas instrumentation linear frequency modulated continuous wave (TI’ LFMCW) radar, which was 26 dBi. The proposed VAA saved 45% of the required implementation area compared to the TI’ LFMCW antenna array. The VAA system was fabricated and tested in an anechoic chamber, and it was found that the simulated and measured patterns of the proposed VAA were highly matched in terms of half-power beamwidth and side lobe level.

THER-04. IS THERE A ROLE FOR CANNABIDIOL IN THE TREATMENT OF CHILDHOOD BRAIN TUMOURS?

Brain tumours are the leading cause of cancer related death in children with limited treatment options and high recurrence rates. Recent evidence suggests there may be anti-tumoral properties of cannabinoids, and of cannabidiol (CBD) in particular. We evaluated the effect of CBD on paediatric brain tumour cell lines in 2D and 3D spheroids; pHGG (SF188), ependymoma (BxD-1425EPN) and human astrocytes. At the CBD EC₅₀ concentration, astrocytic cell death was insignificant. 3D spheroids decreased in size by approximately 20% when cultured in CBD compared to cells only after 5-day exposure. Cell death increased with time after a single dose of CBD. Western Blot showed an increase in Lc3b expression (autophagy) after 24 hours incubation (early cell death) with CBD in both BxD-1425EPN and SF188 with PARP expression (apoptosis) increased after 5 days incubation (late cell death). Cell cycle analysis showed a decrease of cells in G₁ and no change in G₂ indicating cell cycle arrest. In hypoxia, SF188 and BxD-1425EPN cells showed decreased cell death after 24 hours and 5 days when compared to normoxia and an EC₅₀ within acceptable limits could not be achieved. SF188 cells pre-treated with receptor antagonists indicate that CBD was not acting through CB₁, CB₂, GPR18, PPARα or PPARγ receptors but may act as a partial agonist of the TRPV1 and 5-HT_1A receptors and a full agonist of the GPR55 receptor (resazurin assay). This provides evidence that CBD is effective at killing paediatric brain tumour cells and does not have a significant effect on normal astrocytes.

Unicornuate uterus with noncommunicating functional horn: diagnostic workup and laparoscopic horn amputation

OBJECTIVE

To describe the diagnosis and the management of hematometra in a patient with unicornuate uterus with noncommunicating functional horn (hemi uterus and rudimentary uterine hemicavity).

DESIGN

Video case report.

SETTING

Minimally invasive gynaecology unit.

PATIENT(S)

Sixteen-year-old nulliparous woman admitted to the gynaecologic emergency department with pelvic pain during menses.

INTERVENTION(S)

Two-dimensional transvaginal ultrasound, magnetic resonance imaging, and laparoscopic rudimentary horn resection.

MAIN OUTCOME MEASURE(S)

Description of a case of anomaly of the female reproductive tract treated by laparoscopy.

RESULT(S)

After pain reduction and stabilization of clinical condition, ultrasound and magnetic resonance were performed, which detected a hemi uterus with a right rudimentary uterine hemicavity and a hematosalpinx. The removal of the right rudimentary uterine horn was successfully performed. The patient was in good health at the 3-month follow-up visit.

CONCLUSION(S)

Laparoscopic amputation of a functional rudimentary horn is considered the basic and traditional surgical option for women with hemiuterus. A detailed diagnostic evaluation should be performed to avoid misdiagnoses of other anomalies with blind hemicavity, which may be treated by hysteroscopy. Laparoscopic surgery with minimally invasive approach could be an essential tool to treat these cases, achieving optimal results with low postsurgical pain and a short hospital stay.

COVID-19 and Laparoscopic Surgery: Scoping Review of Current Literature and Local Expertise

BACKGROUND

The current coronavirus disease (COVID-19) pandemic is holding the world in its grip. Epidemiologists have shown that the mortality risks are higher when the health care system is subjected to pressure from COVID-19. It is therefore of great importance to maintain the health of health care providers and prevent contamination. An important group who will be required to treat patients with COVID-19 are health care providers during semiacute surgery. There are concerns that laparoscopic surgery increases the risk of contamination more than open surgery; therefore, balancing the safety of health care providers with the benefit of laparoscopic surgery for the patient is vital.

OBJECTIVE

We aimed to provide an overview of potential contamination routes and possible risks for health care providers; we also aimed to propose research questions based on current literature and expert opinions about performing laparoscopic surgery on patients with COVID-19.

METHODS

We performed a scoping review, adding five additional questions concerning possible contaminating routes. A systematic search was performed on the PubMed, CINAHL, and Embase databases, adding results from gray literature as well. The search not only included COVID-19 but was extended to virus contamination in general. We excluded society and professional association statements about COVID-19 if they did not add new insights to the available literature.

RESULTS

The initial search provided 2007 records, after which 267 full-text papers were considered. Finally, we used 84 papers, of which 14 discussed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Eight papers discussed the added value of performing intubation in a low-pressure operating room, mainly based on the SARS outbreak experience in 2003. Thirteen papers elaborated on the risks of intubation for health care providers and SARS-CoV-2, and 19 papers discussed this situation with other viruses. They conclude that there is significant evidence that intubation and extubation is a high-risk aerosol-producing procedure. No papers were found on the risk of SARS-CoV-2 and surgical smoke, although 25 papers did provide conflicting evidence on the infection risk of human papillomavirus, hepatitis B, polio, and rabies. No papers were found discussing tissue extraction or the deflation risk of the pneumoperitoneum after laparoscopic surgery.

CONCLUSIONS

There seems to be consensus in the literature that intubation and extubation are high-risk procedures for health care providers and that maximum protective equipment is needed. On the other hand, minimal evidence is available of the actual risk of contamination of health care providers during laparoscopy itself, nor of operating room pressure, surgical smoke, tissue extraction, or CO₂ deflation. However, new studies are being published daily from current experiences, and society statements are continuously updated. There seems to be no reason to abandon laparoscopic surgery in favor of open surgery. However, the risks should not be underestimated, surgery should be performed on patients with COVID-19 only when necessary, and health care providers should use logic and common sense to protect themselves and others by performing surgery in a safe and protected environment.

Feasibility and safety of laparoscopic approach in obese patients with endometriosis: a multivariable regression analysis

PURPOSE

To evaluate the feasibility and safety of laparoscopic excision of endometriotic lesions in obese women.

METHODS

Retrospective analysis of prospectively collected data involving consecutive women scheduled for complete laparoscopic removal of macroscopic endometriotic lesions between January 2012 and November 2018. Operative time, laparotomic conversion rates, complication rates, and length of hospital stay were recorded.

RESULTS

One thousand two hundred thirty women were enrolled and divided into two main groups, according to the World Health Organization classification of obesity, obese (body mass index ≥ 30 kg/m²) and non-obese (body mass index < 30 kg/m²). During the study period, 91 (7.4% of overall study cohort) obese women underwent surgery. At univariate analyses, significant differences between the two groups were found in terms of age, rates of severe endometriosis, American Society of Anesthesiologists physical status classification ≥ III, and different surgical procedures. Significant differences in terms of median operative time [125 (interquartile range (IQR) 85-165) in obese group vs 110 min (IQR 75-155) in non-obese group, P = 0.04] were observed. There were no significant differences between the obese and non-obese groups with respect to the other variables of interest. After adjusted multivariable regression models for potential confounders, difference in operating time (coefficient of 13.389; 95% CI 1.716, 25.060) was still found to be significant.

CONCLUSION

In our tertiary care referral center, laparoscopic removal of endometriosis is feasible and safe, except for a slight increase of operative time and conversion rate.

Rectosigmoid Endometriosis Vascular Patterns at Intraoperative Indocyanine Green Angiography and their Correlation with Clinicopathological Data

Introduction. The objective of the study was to evaluate the presence of different rectosigmoid endometriosis (RSE) vascular patterns using intraoperative indocyanine green (ICG) angiography and their correlation with clinicopathological data. Material and Methods. A prospective pilot study on 30 consecutive symptomatic women affected by RSE and scheduled for minimally invasive surgery between May 2018 and January 2019. ICG was used for the intraoperative evaluation of RSE vascularization. Perfusion grade was classified as follows: 0-1 = no or low fluorescence (hypovascular pattern); 2 = regular fluorescence, similar to healthy surrounding rectosigmoid tract (isovascular pattern); and 3-4 = diffuse or abundant fluorescence (hypervascular pattern). Results. Thirty women were intravenously injected with ICG after nodule exposure. No adverse effects related to ICG use were noted. After a 5- to 50-s latency from ICG injection, the real-time direct visualization of RSE perfusion showed diffuse or abundant fluorescence in 12/30 (40%) women, while in the remaining 18/30 (60%), fluorescence was poor or absent. No statistical differences were observed between the 2 groups regarding preoperative, intraoperative, and histological variables analyzed, except for a maximum diameter of bowel lesions and microvessel density (MVD). Hypovascular nodules had a larger maximum diameter (39.5 ± 15.6 mm vs 30.3 ± 11.4 mm, P < .05) and lower MVD (154.6+/43.6 vs 281.1+/-77.4, P < .05) than hypervascular ones. Conclusions. ICG angiography is a feasible and safe technique to intraoperatively assess RSE vascularization. The majority (60%) of endometriotic nodule presented a hypovascular pattern. The hypovascular pattern seems to be associated with a larger nodule size and lower MVD.

Laparoscopic surgery for benign adnexal conditions under spinal anaesthesia: Towards a multidisciplinary minimally invasive approach

•

In general surgery locoregional anaesthesia increased laparoscopy advantages.

•

28 women submitted to gynaecological laparoscopy for benign adnexal conditions.

•

13 patients under spinal anaesthesia, 15 under general anaesthesia.

•

Less postoperative pain and reduced need f opioids in the spinal anaesthesia arm.

•

Earlier mobilization and return of bowel function in the spinal anaesthesia arm.

Background

Laparoscopic gynaecological surgery is commonly performed under general anaesthesia with endotracheal intubation. In general surgery, locoregional anaesthesia was applied to laparoscopic procedures, increasing minimally invasive surgery advantages.

Aims

To assess and compare postoperative pain after laparoscopic adnexal procedures for benign conditions under spinal anaesthesia (SA) versus general anaesthesia (GA). Furthermore, anaesthesiologic, surgical and clinical data were evaluated in both groups.

Materials and Methods

This is a prospective cohort study performed in a tertiary level referral centre for minimally invasive gynaecological surgery (Gynaecology and Human Reproduction Physiopathology, University of Bologna). Women scheduled for adnexal laparoscopic surgery for benign conditions between February and May 2019 were assigned to receive either SA or GA with endotracheal intubation. A sample size of 13 women per group was needed to detect a 2-point difference in pain scores.

Main findings

13 women were enrolled in the SA arm, 15 in the GA arm. In the SA cohort, the most common intraoperative adverse event was shoulder pain, reported by 3/12 women. At 1, 8, 12, 24 and 48 h after surgery pain was significantly lower in the SA arm (p < .05). Patients submitted to SA experienced no need for opioid drugs administration, unlike those receiving GA. Patients’ mobilization and return of bowel function were noted significantly earlier in the SA group (p < .05).

Conclusions

SA is a feasible, safe and effective anaesthesiologic technique for laparoscopic gynaecological procedures for benign conditions, allowing a better control of postoperative pain. Women undergoing SA achieve earlier mobilization and bowel canalization. During the Covid-19 pandemics, SA could be useful in reducing the need for invasive procedures on respiratory tract.

Acute abdominal pain in non-pregnant endometriotic patients: not just dysmenorrhoea. A systematic review

Endometriosis, defined as the presence of functional endometrial tissue outside the uterine cavity, presents mainly with pelvic pain and infertility. Acute abdominal pain in non-pregnant patients with endometriosis might be minimised as a typical feature of the disease, while endometriosis is rarely considered in the differential diagnosis of acute abdominal pain. Our objective was to conduct a systematic review of the current literature of cases of acute abdomen/acute abdominal pain in non-pregnant endometriotic patients. We performed a PubMed/MEDLINE search of studies published from January 1990 to December 2018, selecting English language reports and series of non-pregnant patients with acute abdomen and histological confirmation of endometriosis. The studies were revised by two independent authors. Data were abstracted and compiled for analysis. Fifty articles reporting 62 patients were identified. The complications were classified according to anatomical sites in bowel, urinary tract, and genital organs emergencies. Rarely was the first diagnostic hypothesis endometriosis, misdiagnosis was frequent. The time frame from symptoms onset to management was often long. This is the first systematic review evaluating acute abdomen/acute abdominal pain in non-pregnant endometriotic patients. These conditions are rare but possibly life-threating and require prompt diagnosis and emergent medical or surgical treatment.

Use of Indocyanine Green for Intraoperative Perfusion Assessment in Women with Ureteral Endometriosis: A Preliminary Study

STUDY OBJECTIVE

To evaluate the feasibility, safety, and potential usefulness of near-infrared imaging (NIR) with indocyanine green (ICG) to assess ureteral perfusion after conservative surgery (ureterolysis or nodule removal) for ureteral endometriosis. Any changes to the surgical plan regarding intraoperative ureteral stent placement after NIR-ICG evaluation and early postoperative outcomes were recorded.

DESIGN

Prospective case series study.

SETTING

Tertiary level referral center for endometriosis and minimally invasive gynecology.

PATIENTS

Consecutive symptomatic women scheduled for laparoscopic conservative ureteral surgery for ureteral endometriosis.

INTERVENTIONS

After ureterolysis or nodule removal, residual perfusion of the ureters with regular caliber and peristalsis was evaluated through NIR-ICG imaging. Ureteral perfusion grade was defined as absent, irregular, or regular. Time required for NIR-ICG assessment, interoperator agreement regarding ureteral perfusion grade, any changes to the surgical plan after NIR-ICG evaluation, perioperative complications, and clinical-radiologic outcomes at early follow-up were recorded.

MEASUREMENTS AND MAIN RESULTS

A total of 31 ureters were examined with NIR-ICG imaging after conservative ureteral procedures. ICG assessment required 5.4 + 2.3 minutes. No complications related to fluorescence imaging were observed. Local ischemia supporting ureteral stent placement was suspected in 5 ureters (16.1%) at white light. Of these, 2 (40.0%) presented regular fluorescence; thus, ureteral stent placement was avoided. In the remaining 3 (60.0%), NIR-ICG confirmed irregular or absent fluorescence, requiring ureteral stent placement. Interoperator agreement regarding NIR-ICG evaluation was high. At a 3-month follow-up, all procedures were clinically and radiologically successful.

CONCLUSION

NIR-ICG imaging after conservative surgery for ureteral endometriosis seems to be a feasible, safe, and useful tool to assess ureteral perfusion and guide surgical decision, together with other visual cues at white light. However, this approach needs to be validated by further larger and controlled studies.

Painful Love: Superficial Dyspareunia and Three Dimensional Transperineal Ultrasound Evaluation of Pelvic Floor Muscle in Women with Endometriosis

We conducted an observational study between March 2015 and March 2018 in our academic center. Symptomatic, sexually active women with clinical and sonographic diagnosis of deep infiltrating endometriosis (DIE) or isolated ovarian endometriosis were enrolled. Women were asked to rank endometriosis-related symptoms, especially superficial and deep dyspareunia. Moreover, 3D transperineal ultrasound was performed to assess the levator hiatus area (LHA) evaluating pelvic floor muscle (PFM) morphometry. Women with endometriosis seem to have a high prevalence of superficial dyspareunia and three-dimensional transperineal ultrasound seems to be a viable technique to assess PFM morphometry in these women.

Recurrent endometriosis: a battle against an unknown enemy

Recurrence of endometriosis after conservative surgery is not an uncommon finding. There is no uniformity, however, on what the term 'recurrence' means. Recurrence is variously defined in the literature as the relapse of pain, clinical or instrumental detection of an endometriotic lesion, repeat rise in CA 125 levels, or evidence of recurrence found during repeat surgery. Consequently, the reported recurrence rate varies widely (0-89%) in the different series, depending on its definition and the type of study performed. As endometriosis recurrence seems to be an indeterminate enemy, we set out to examine exactly what we were fighting in our everyday battle. In this narrative review, we aimed to seek an answer to questions related to endometriosis recurrence, some of which are often asked by our patients.

First Impressions Can Be Deceiving: Surgical Outcomes of Laparoscopic Myomectomy in Patients Pretreated with Ulipristal Acetate

STUDY OBJECTIVE

To compare enucleation time, total operative time, and perioperative complications during laparoscopic myomectomy in patients pretreated with ulipristal acetate (UPA) compared with untreated patients.

DESIGN

Prospective, observational pilot study.

SETTING

Tertiary referral center of minimally invasive gynecologic surgery, Sant'Orsola Academic Hospital, Bologna, Italy.

PATIENTS

Seventy-four of 108 patients scheduled for laparoscopic myomectomy from January to November 2017 were enrolled.

INTERVENTIONS

Laparoscopic myomectomy following pretreatment with UPA or no hormonal pretreatment therapy.

MEASUREMENTS AND MAIN RESULTS

Of the 74 patients who were enrolled, 29 were pretreated with UPA (UPA group), and 45 did not receive any hormonal therapy before surgery (control group). Surgeons, blinded to patient pre-operative treatment, completed a 3-item questionnaire after each procedure to evaluate surgical difficulty. Based on surgeon response, myomas in the UPA group appeared softer and more difficult to enucleate because of less clear cleavage planes than the control group. The overall difficulty of myoma detachment from the myometrium was judged considerably higher in the UPA group. Despite this, enucleation time, total operative time, and perioperative complications were not statistically different in the 2 groups.

CONCLUSION

Myomas in patients pretreated with UPA are subjectively less easy to enucleate; however, surgical times and perioperative outcomes are not affected by pretreatment with UPA.

Keep Your Landmarks Close and the Hypogastric Nerve Closer: An Approach to Nerve-sparing Endometriosis Surgery

OBJECTIVE

Excisional techniques used to surgically treat deep infiltrating endometriosis (DIE) can result in inadvertent damage to the autonomic nervous system of the pelvis, leading to urinary, anorectal, and sexual dysfunction [1-4]. This educational video illustrates the autonomic neuroanatomy of the pelvis, identifying the predictable location of the hypogastric nerve in relation to other pelvic landmarks, and demonstrates a surgical technique for sparing the hypogastric nerve and inferior hypogastric plexus.

DESIGN

Using didactic schematics and medical drawings, we discuss and illustrate the autonomic neuroanatomy of the pelvis. With annotated laparoscopic footage, we demonstrate a stepwise approach for identifying, dissecting, and preserving the hypogastric nerve during pelvic surgery.

SETTING

Tertiary care academic hospitals: Mount Sinai Hospital in Toronto, Ontario, Canada, and S. Orsola Hospital in Bologna, Italy.

INTERVENTIONS

Radical excision of DIE with adequate identification and sparing of the hypogastric nerve and inferior hypogastric plexus bilaterally was performed, following an overview of pelvic neuroanatomy. The superior hypogastric plexus was described and the hypogastric nerve, the most superficial and readily identifiable component of the inferior hypogastric plexus, was identified and used as a landmark to preserve autonomic bundles in the pelvis. The following steps, illustrated with laparoscopic footage, describe a surgical technique developed to identify and preserve the hypogastric nerve and the deeper inferior hypogastric plexus without the need for more extensive pelvic dissection to the level of the sacral nerve roots: (1) transperitoneal identification of the hypogastric nerve, with a pulling maneuver for confirmation; (2) opening of the retroperitoneum at the level of the pelvic brim and retroperitoneal identification of the ureter; (3) medial dissection and identification of the hypogastric nerve; and (4) lateralization of the hypogastric nerve, allowing for safe resection of DIE.

CONCLUSION

The hypogastric nerve follows a predictable course and can be identified, dissected, and spared during pelvic surgery, making it an important landmark for the preservation of pelvic autonomic innervation.

Deep Infiltrating Endometriosis and Spontaneous Hemoperitoneum: A Life-Threatening Situation Treated by Laparoscopy

OBJECTIVE

To describe a case of spontaneous hemoperitoneum in a woman affected by deep infiltrating endometriosis (DIE).

DESIGN

Technical video showing laparoscopic management of a spontaneous hemoperitoneum in a patient with DIE.

SETTING

Minimally Invasive Gynecological Unit, Sant'Orsola Academic Hospital, Bologna, Italy.

INTERVENTION

A 35-year-old nulliparous woman was admitted to our gynecologic emergency room because of pelvic pain and a fainting sensation. She had a history of DIE and had been followed for 6 months by our outpatient clinics. The patient underwent an immediate laparoscopy because of the rapid worsening of clinical conditions. After blood suction and difficult adhesiolysis, a vascular lesion with a huge blood flow, close to the left utero-ovarian ligament, was detected. Selective coagulation was performed with good results. During the follow-up visit after 1 month, the patient reported good health. Written informed consent was obtained from the patient for publication of this case report.

CONCLUSION

Spontaneous hemoperitoneum represents a rare and life-threatening complication associated with endometriosis. In patients with hemoperitoneum and a history of endometriosis, it is important to pay attention to the possible presence of uncommon bleeding localizations. Laparoscopy was useful and effective in this challenging situation, identifying the bleeding source and performing selective coagulation.

Leyomiomatosis peritonealis disseminata associated with ovarian endometriosis in a patient submitted to hysteroscopic myomectomy

OBJECTIVE

To describe laparoscopic management of a case of leyomiomatosis peritonealis disseminata associated with ovarian endometriosis.

DESIGN

Surgical video article.

SETTING

Academic hospital.

PATIENT

We present a case of a 30-year-old woman referred to our clinic for abdominal and pelvic pain and dyspareunia. A hysteroscopic myomectomy was reported as previous surgical history. At ultrasound examination, a left ovarian cyst of 4 cm suspected for typical endometrioma and a mild hydroureteronephrosis of left kidney were revealed. The patient was scheduled for laparoscopic surgery.

INTERVENTIONS

During laparoscopy, multiple nodules were found simulating widespread metastases involving colon, small bowel, omentum, right diaphragmatic dome, gastric surface, vesico-uterine area and abdominal peritoneum. Several biopsies and a peritoneal washing were performed, suspecting a peritoneal carcinomatosis. The histological frozen section examination revealed a possible benign disease, requiring further immunohistochemical study that diagnosed leiomyomatosis peritonealis. A second laparoscopy was then performed after one month. Enucleation of the left ovarian endometriotic cyst with classic stripping technique was performed. The left ureter was compressed by a fibrotic nodule of 5 cm that was isolated and removed. Operating time was 80 minutes. The postoperative course was uneventful and the patient was discharged on postoperative day 2.

MAIN OUTCOME MEASURES

Description of a case of leiomyomatosis peritonealis disseminata in a patient with no previous history of intra-abdominal morcellation.

RESULTS

The removal of the left ovarian endometriotic cyst and the periureteral nodule was successfully performed. The patient reported good health conditions without hydroureteronephrosis at six months follow up visit.

CONCLUSIONS

Leiomyomatosis peritonealis disseminata is a rare clinical disorder characterized by proliferation of nodules, consisted by smooth muscle cells. The association of this condition with endometriosis has been described in other studies. Despite several medical therapies have been proposed (chemotherapy, aromatase inhibitor, gonadotropin-releasing hormone agonist), surgical excision remains a good option, frequently performed for symptoms palliation. Laparoscopic approach might be considered the procedure of choice in case of symptomatic women with leiomyomatosis peritonealis disseminata.

Endometriosis of the Appendix: When to Predict and How to Manage-A Multivariate Analysis of 1935 Endometriosis Cases

STUDY OBJECTIVE

To evaluate appendiceal endometriosis (AE) prevalence and risk factors in endometriotic patients submitted to surgery.

DESIGN

A retrospective cohort study.

SETTING

A tertiary level referral center, university hospital.

PATIENTS

One thousand nine hundred thirty-five consecutive patients who underwent surgical removal for symptomatic endometriosis.

INTERVENTIONS

Electronic medical records of patients submitted to surgery over a 12-year period were reviewed. We assessed any correlation between demographic, clinical, and surgical variables and AE. In our center, appendectomy was performed using a selective approach. Appendix removal was performed in case of gross abnormalities of the organ, such as enlargement, dilation, tortuosity, or discoloration of the organ or the presence of suspected endometriotic implants.

MEASUREMENTS AND MAIN RESULTS

AE prevalence was 2.6% (50/1935), with only 1 false-positive case at gross intraoperative evaluation. In multivariate analysis using a stepwise logistic regression model, independent risk factors for AE were adenomyosis (adjusted odds ratio [aOR] = 2.48; 95% confidence interval [CI], 1.32-4.68), right endometrioma (aOR = 8.03; 95% CI, 4.08-15.80), right endometrioma ≥5 cm (aOR = 13.90; 95% CI, 6.63-29.15), bladder endometriosis (aOR = 2.05; 95% CI, 1.05-3.99), deep posterior pelvic endometriosis (aOR = 5.79; 95% CI, 2.82-11.90), left deep lateral pelvic endometriosis (aOR = 2.11; 95% CI, 1.10-4.02), and ileocecal involvement (aOR = 12.51; 95% CI, 2.07-75.75).

CONCLUSION

Among patients with endometriosis submitted to surgery, AE was observed in 2.6%, and it was associated with adenomyosis, large right endometrioma, bladder endometriosis, deep posterior pelvic endometriosis, left deep lateral pelvic endometriosis, and ileocecal involvement.

Modulatory Role of Vitamins A and E on Memory and Motor Functions of Cyanide Induced Neurotoxicity in Adult Swiss Mice

Cyanide is a potent neurotoxic substance that can initiate series of intracellular reactions leading to oxidativestress. To evaluate effect of sublethal administration of potassium cyanide (KCN) on sensorimotor functions and long termvisuo-spatial learning and memory in adult Swiss mice and possible ameliorative role of vitamins A and E. These vitaminsA and E (dietary) are antioxidants that have scavenging properties against free radicals and reactive oxygen species as aresult of oxidative stress induced by cyanide. Thirty-five mice weighing between 18-22 g were used for the study. Theanimals were randomly divided into five groups (n = 7) and exposed to sublethal concentration of potassium cyanide (10%LD50; 1.5 mg/kg). KCN was administered orally while vitamin A (25 mg/kg) and vitamin E (50 mg/kg) were administeredintra-peritoneal (IP) once daily for 28 days. Potassium cyanide (KCN) was first administered and after 10 minutes intervals,followed by vitamin A and then E after 5 minutes, vitamin E were administered across the different treatment groups. Micewere examined for signs of toxicity. Vitamins pre-treatment ameliorated toxic signs. In the dynamics of wire grid, coathanger and stationary beam test, the latency to fall in weeks 2 and 4 were statistically significant. In acquisition and retention,using elevated plus maze (EPM), KCN treated group recorded high transfer latencies in seconds (50.40±1.72 secs) and(57.60±0.93 secs) as compared to group IV (29.40±0.68 secs; 5.60±0.60 secs). Cyanide is a neurotoxin that affects motorfunctions with progressive decline in motor strength and coordination. KCN affects acquisition and retention memory whilepre-treatment with antioxidant vitamins A and E ameliorated these deficits.

Transvaginal and transperineal ultrasound follow-up after laparoscopic correction of uterine retrodisplacement in women with posterior deep infiltrating endometriosis

BACKGROUND

Retrodisplacement of the uterus (retroflexion and/or retroversion) may be associated with pelvic pain symptoms and posterior deep infiltrating endometriosis (DIE). Previous studies in symptomatic women with retrodisplacement of the uterus showed the efficacy of hysteropexy in terms of pain symptoms improvement.

AIM

To evaluate sonographic, clinical and surgical outcomes of a hysteropexy technique MATERIALS AND METHODS: Laparoscopic round ligament plication and tilting of the uterine fundus in women with uterine retrodisplacement and posterior deep infiltrating endometriosis was performed. Forty-two symptomatic women were enrolled and the sonographic data of each (angle of uterine version and uterine flexion, uterine mobility) was assessed before and after surgery with transvaginal and transperineal approaches. Women were also evaluated at 1, 6 and 12 months after surgery for pain symptoms with a numerical rating scale (dysmenorrhoea, dyspareunia and chronic pelvic pain), intraoperative data and surgical complications.

RESULTS

The additional mean operative time of hysteropexy procedure was 8 ± 3 min. At early follow-up both the uterine angles were significantly (P < 0.001) reduced. At 12-month follow-up, seven patients (16.7%) presented a retroverted uterus, while 12 (28.6%) presented a retroflexed uterus; the sliding sign remained negative in four patients (9.5%). A significant improvement of symptoms (P < 0.001) was observed during the follow-up.

CONCLUSION

Laparoscopic hysteropexy appears as an effective additional surgical procedure, which can temporarily correct the uterine position in order to reduce the risk of postoperative adhesions.

Pelvic floor muscle assessment on three- and four-dimensional transperineal ultrasound in women with ovarian endometriosis with or without retroperitoneal infiltration: a step towards complete functional assessment

OBJECTIVES

Previous studies comparing women with deep infiltrating endometriosis (DIE) and healthy controls have underlined an association between pelvic floor muscle (PFM) hypertonic dysfunction and deep lesions. The aim of this study was to compare the morphometry of PFM in women affected by ovarian endometriosis with DIE vs those without DIE in order to assess the impact of retroperitoneal infiltration by the disease on PFM function.

METHODS

This was a prospective study conducted between March 2015 and December 2016 on symptomatic women with a clinical and sonographic diagnosis of ovarian endometriosis with or without DIE, scheduled for laparoscopic surgery. We excluded patients with current or previous pregnancy, previous surgery for deep endometriosis, other causes of chronic pelvic pain or congenital or acquired abnormalities of pelvic floor anatomy. Three- and four-dimensional transperineal ultrasound was performed to evaluate PFM morphometry and assess levator hiatal area (LHA) and diameters at rest, during PFM contraction and during Valsalva maneuver. All volumes were analyzed offline by an investigator blinded to the clinical data.

RESULTS

One hundred and fourteen patients with ovarian endometriosis were enrolled in the study, 75 with DIE and 39 without DIE. The diagnosis of endometriosis was confirmed by histological examination in all patients. Compared with women without DIE, women with DIE showed a smaller LHA at rest, during contraction and during Valsalva maneuver (P = 0.03, P = 0.03 and P = 0.02, respectively) and a smaller reduction in LHA during PFM contraction (P = 0.04).

CONCLUSIONS

Women with ovarian endometriosis who were affected by DIE showed smaller hiatal dimensions than did women without DIE. Considering that PFM dysfunction in patients with DIE could cause pain symptoms and pelvic organ dysfunction, transperineal ultrasound could allow a more complete functional assessment and tailored therapy. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

BACKGROUND

Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world.

METHODS

This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231.

FINDINGS

Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p<0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05-2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p<0·001).

INTERPRETATION

Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication.

FUNDING

DFID-MRC-Wellcome Trust Joint Global Health Trial Development Grant, National Institute of Health Research Global Health Research Unit Grant.

Short-term histopathological effects of dienogest therapy on ovarian endometriomas: in vivo, nonrandomized, controlled trial

Ovarian endometriosis is a common gynecological disorder. To date, progestins are recommended as the first-line medical treatment for symptomatic ovarian endometriosis. The aim of this study was to evaluate the main histopathological effects of short-term dienogest therapy in patients with ovarian endometriomas scheduled for surgery. A prospective, nonrandomized controlled trial, including 70 symptomatic women with single ovarian endometriotic cyst (diameter between 30-50 mm) was conducted. Women scheduled for surgery were divided into two groups, depending on the treatment established at enrollment: 36 women received progestin therapy with dienogest (P group) and 34 women received no therapy (C group). At histopathological examination necrosis, inflammation, decidualization, glandular atrophy and angiogenesis were blindly evaluated. At tissue level, decidualization was significantly more frequent in P group compared to C group (p = .001). A nonsignificant tendency (p = .29) towards a slight decreased inflammation in P group was found. No significant differences were observed between the two groups in terms of necrosis, glandular atrophy and angiogenesis. The study suggests that high decidualization rate and the tendency to reduced inflammatory reaction in the short-term administration of dienogest might contribute to its therapeutic efficacy.

Severe ureteral endometriosis: frequency and risk factors

Ureteral endometriosis (UE) can be classified as severe when there is obstruction to urinary flow (ureteral compression (UC)). In this retrospective study on 205 patients, we evaluated intraoperatively the frequency of severe ureteral endometriosis (UE) in women with UE and, secondarily, risk factors associated with UC. We documented intraoperatively ureteral UC in 124 (60.5%) patients with UE. A significantly lower body mass index (BMI) was observed in women with UC than in women without UC (p = .02). A significant association was found between UC and parametrial endometriosis (p = .001). In multivariable analysis, these variables remained significantly associated with UC. Ureteral compression is common in patients with UE, especially in women with parametrial infiltration and a low BMI.

Pelvic floor muscle dysfunction on 3D/4D transperineal ultrasound in patients with deep infiltrating endometriosis: a pilot study

OBJECTIVE

Pelvic floor muscle (PFM) dysfunction seems to play an important role in the pathophysiology of pelvic pain, including that associated with deep infiltrating endometriosis (DIE). The aim of this study was to evaluate the static and dynamic morphometry of the PFM using three-dimensional (3D) and four-dimensional (4D) transperineal ultrasound in women with DIE compared with asymptomatic healthy women.

METHODS

This was a pilot, prospective study conducted at our tertiary center between March and November 2015. Fifty nulliparous women with DIE (study group) and 35 nulliparous asymptomatic healthy women (control group) were included. 3D/4D transperineal ultrasound examination of the PFM was performed in both groups. Levator hiatal area (LHA) and anteroposterior and left-right transverse diameters were evaluated at rest, on maximum PFM contraction and on maximum Valsalva maneuver. Persistent levator ani muscle (LAM) coactivation during Valsalva maneuver was investigated.

RESULTS

Compared with the control group, women with DIE had a smaller LHA at rest (P = 0.03) and during Valsalva maneuver (P < 0.01). Furthermore, reduction in LHA during PFM contraction (P < 0.001) and enlargement in LHA during Valsalva maneuver (P = 0.01) were significantly less marked. In comparison with controls, women with DIE presented a higher frequency of LAM coactivation during Valsalva maneuver, although this difference did not reach statistical significance (P = 0.05).

CONCLUSIONS

3D and 4D transperineal ultrasound is an objective and non-invasive method for PFM morphometry and may have a role in detecting PFM dysfunction in women with DIE. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Therapeutic outcome of 6198 interferon-naïve Egyptian patients with chronic hepatitis C: a real-life experience and lessons to be learned in DAAs' era

Antiviral therapy for HCV infection has been validated in randomized controlled clinical trials, but its value in the real world is less well studied. There is relatively little data on real-world responses to interferon-based therapies for patients with genotype 4 infection. We aimed to examine experience with large-scale access to antiviral therapy in chronic HCV in a real-life clinical setting in Egypt. Detailed pretreatment data of 6198 IFN-naïve chronic HCV patients who had received PEG-IFN/RBV therapy at Cairo-Fatemic Hospital, Egypt, between 2009 and 2012 were obtained from the HCV database. At week 12, 95.7% of patients had undetectable HCV RNA, and by week 24 and 48, breakthrough was 6% and 4%, respectively. However, 43.7% of patients discontinued treatment prematurely, and intent to treat end of treatment response was 44.6% (79.3% per protocol). Sustai-ned response data were available from only 1281 patients and was 84.9%. Haematological abnormalities were comparable in patients who did or did not comply with therapy. This is the first real-world, large-scale experience of antiviral therapy in chronic HCV in Egypt. Suboptimal response in HCV predominantly genotype 4 was mainly driven by noncompliance as well as gaps in the healthcare system leading to treatment discontinuation. These results need to be considered in the era of all oral antiviral regimes.

Event Recognition for Contactless Activity Monitoring Using Phase-Modulated Continuous Wave Radar

OBJECTIVES

The use of remote sensing technologies such as radar is gaining popularity as a technique for contactless detection of physiological signals and analysis of human motion. This paper presents a methodology for classifying different events in a collection of phase modulated continuous wave radar returns. The primary application of interest is to monitor inmates where the presence of human vital signs amidst different, interferences needs to be identified.

METHODS

A comprehensive set of features is derived through time and frequency domain analyses of the radar returns. The Bhattacharyya distance is used to preselect the features with highest class separability as the possible candidate features for use in the classification process. The uncorrelated linear discriminant analysis is performed to decorrelate, denoise, and reduce the dimension of the candidate feature set. Linear and quadratic Bayesian classifiers are designed to distinguish breathing, different human motions, and nonhuman motions. The performance of these classifiers is evaluated on a pilot dataset of radar returns that contained different events including breathing, stopped breathing, simple human motions, and movement of fan and water.

RESULTS

Our proposed pattern classification system achieved accuracies of up to 93% in stationary subject detection, 90% in stop-breathing detection, and 86% in interference detection.

CONCLUSION

Our proposed radar pattern recognition system was able to accurately distinguish the predefined events amidst interferences.

SIGNIFICANCE

Besides inmate monitoring and suicide attempt detection, this paper can be extended to other radar applications such as home-based monitoring of elderly people, apnea detection, and home occupancy detection.

Model of human breathing reflected signal received by PN-UWB radar

Human detection is an integral component of civilian and military rescue operations, military surveillance and combat operations. Human detection can be achieved through monitoring of vital signs. In this article, a mathematical model of human breathing reflected signal received in PN-UWB radar is proposed. Unlike earlier published works, both chest and abdomen movements are considered for modeling the radar return signal along with the contributions of fundamental breathing frequency and its harmonics. Analyses of recorded reflected signals from three subjects in different postures and at different ranges from the radar indicate that ratios of the amplitudes of the harmonics contain information about posture and posture change.