A patient presenting with a perivascular epithelioid cell tumor in the broad ligament: a case report

<p>Abstract</p> <p>Introduction</p> <p>Perivascular epithelioid cell tumors are a family of rare mesenchymal tumors composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. They can originate in any visceral organ or soft tissue and include a range of lesions such as angiomyolipoma, clear cell 'sugar' tumor of the lung, lymphangioleiomyomatosis and clear cell myomelanocytic tumors of the falciparum ligament/ligament teres. Due to their rarity and varied sites and presentation, management of these tumors remains highly challenging.</p> <p>Case Presentation</p> <p>A 46-year-old para 2 Caucasian woman initially presented to the general surgeons at our hospital in North West London with abdominal pain. Laparoscopy revealed a right broad ligament hematoma, which was thought to be iatrogenic in origin, from insertion of the Veress needle at the time of surgery, and was managed conservatively. Upon her re-presentation two months later with severe pain, ultrasound scanning revealed the hematoma had increased in size and she underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histology results from necrotic tissue from the hematoma led to a diagnosis of perivascular epithelioid cell tumor. She was then referred to a tertiary oncology center, where she underwent several further operations in an attempt to debulk the tumor for symptomatic relief of her pain, with limited success. She is now taking the immunosuppressive drug sirolimus, which has produced a modest reduction in tumor size. She is now 47 months on from initial presentation.</p> <p>Conclusions</p> <p>A literature search has revealed only six other case reports of broad ligament perivascular epithelioid cell tumors, with varied presentations and management. The longest duration of follow-up was 21 months. Only five other cases of perivascular epithelioid cell tumor managed with sirolimus have been reported. We therefore feel that this report highlights some of the difficulties in diagnosing perivascular epithelioid cell tumors, and sheds light on management strategies for a very rare gynecological tumor in addition to sharing our experience in the use of sirolimus in its treatment.</p

Monitoring the Progression of Micro-Pitting in Spur Geared Transmission Systems Using Online Health Monitoring Techniques

Micro-pitting is a fatigue effect that occurs in geared transmission systems due to high contact stress, and monitoring its progression is vital to prevent the eventual failure of the tooth flank. Parameter signature analysis has been successfully used to monitor bending fatigue failure and advanced phases of gear surface fatigue failure such as macro-pitting and scuffing. However, due to modern improvements in steel production the main cause of gear contact fatigue failure can be attributed to surface micro-pitting rather than sub-surface phenomena. Responding to the consequent demand to detect and monitor the progression of micro-pitting, this study experimentally evaluated the development of micro-pitting in spur gears using vibration and oil debris analysis. The paper presents the development of an online health monitoring system for use with back-to-back gear test rigs. The results validate the system capabilities in detecting early gear defects and reliably identifying the type of failure so that it can be used in predictive health monitoring (PHM) systems

Improvement of Driverless Cars' Passengers on Board Health and Safety, using Low-Cost Real-Time Heart Rate Monitoring System

In this work, a real-time unobtrusive heart rate monitoring system is proposed and implemented. The proposed system aims to monitor the heart rate of the passengers by using a low-cost camera, which can be readily embedded in the car's rear-view mirror. Additionally, we integrate this system with the main system of our test driverless car, and we propose how driverless cars should act in response to serious medical emergency situations. Moreover, we investigate how this system can benefit from the promising features of Google I/O and Google AI. Our approach is based on Remote Photoplethysmography (rPPG), in which the heart rate is extracted from the subtle tiny changes occurring in the skin color of the face during every pulsation. The face is automatically detected and tracked, then the raw signal is calculated from each frame over a 10-seconds sliding window. After that, a series of signal processing techniques are implemented on the raw signals to recover the heart rate frequency. Finally, the resultant heart rate measurements are processed and stored, then we compare it with ground truth measurements values obtained using pulse oximeter