Page kidney phenomenon in kidney allograft following abdominal trauma

The page kidney phenomenon is often associated in patients with abdominal trauma. External compression from a renal hematoma can cause hypertension, and presentation can be delayed following the initial injury. For patients who have a kidney allograft, page kidneys may lead to renal insufficiency and acute renal failure due to the absence of a contralateral kidney to compensate. This case report discusses the identification and management of a page kidney in a kidney allograft recipient within three months following transplantation.

Covered Stent Implantation for Treatment of Iliac Vein Rupture During Percutaneous Left Atrial Appendage Occlusion

An 82-year-old woman who experienced an iatrogenic external iliac vein perforation during a left atrial appendage occlusion procedure was successfully treated by endovascular graft implantation. We report the short- and long-term outcomes of the procedure. (Level of Difficulty: Advanced.).

A rare case of parathyroid crisis with respiratory failure successfully treated using extracorporeal membrane oxygenation

Parathyroid crisis, which might occur during the natural history of primary hyperparathyroidism, presents fatal hypercalcemia. Although hyperparathyroidism is known to cause metastatic pulmonary calcification, parathyroid crisis with respiratory failure is rarely reported. Here, we present a case of parathyroid crisis with respiratory failure due to parathyroid adenoma. For the first 2 weeks after admission to our hospital, the patient was treated with hydration, calcium-lowering agents, dialysis and extracorporeal membrane oxygenation, with gradual improvement in her respiratory condition as blood calcium levels decreased. However, she still needed oxygen even after that. Therefore, parathyroidectomy was performed on day 48, and she no longer needed oxygen after the surgery. Chest computed tomography scan also demonstrated improvement in pulmonary calcification, although it did not completely disappear even 4 months after parathyroidectomy. Parathyroid crisis is an endocrine emergency, and its possibility should be considered in patients with respiratory failure with hypercalcemia.

Lung metastasis from gastric cancer presenting as diffuse ground-glass opacities

Most metastatic lung tumors display well-defined, round, multiple nodular shadows, whereas the presence of diffuse ground-glass opacities on chest computed tomography generally suggests non-malignant conditions. Here, we report an unusual case of pulmonary metastasis from gastric cancer in which diffuse ground-glass opacities were observed in all lung segments. A 59-year-old man with a 3-month history of worsening chest pain and shortness of breath was referred to the pulmonary clinic. Chest computed tomography revealed low attenuation areas, suggesting emphysema, along with diffuse ground-glass opacities and interlobular septal thickening in both lungs. A transbronchial lung biopsy specimen revealed signet-ring cell carcinoma infiltrating the alveolar septa. Immunohistochemical staining of the cancer cells was positive for CDX-2, cytokeratin 7, and cytokeratin 20, and negative for surfactant apoprotein-A, TTF-1, and Napsin A. Gastrointestinal endoscopy revealed an ulcerative tumor in the stomach, and a biopsy from the tumor demonstrated malignant cells with similar morphology and immunophenotypes as those in the lungs. The final diagnosis was diffuse lung metastasis from gastric cancer. Our case shows that although multiple, well-defined nodules are typically considered to be the classic presentation of pulmonary metastasis, clinicians should also be aware of the possibility of pulmonary metastasis presenting as diffuse ground-glass opacities.

Immunoglobulin G4-Related Multiple Giant Coronary Artery Aneurysms and a Single Left Gastric Artery Aneurysm

Coronary artery aneurysm (CAA) is potentially life-threatening. We describe a case of multiple giant CAAs and a single left gastric artery aneurysm caused by immunoglobulin G4-related disease (IgG4-RD). Our case highlights the significance of assessing IgG4-RD in the diagnosis of CAA and screening for other concurrent cardiovascular involvements. (Level of Difficulty: Intermediate.)

Fulminant Eosinophilic Myocarditis: A Rare and Life-Threatening Presentation of Eosinophilic Granulomatosis With Polyangiitis

We describe a case of fulminant eosinophilic myocarditis as the first presentation of eosinophilic granulomatosis with polyangiitis, promptly managed with extracorporeal membrane oxygenation. This case highlights the multidisciplinary work involving all health care professionals in the acute management of these patients and discusses it from an educational point of view. (Level of Difficulty: Intermediate.)

A case of pulmonary Mycobacterium heckeshornense infection in a healthy Japanese man

A 72-year-old man, healthy, smoker, with long-standing cough, was referred to our hospital and his chest X-ray (CXR) revealed a cavity lesion in the right upper lobe. Direct sputum smears, but not culture in solid medium, were positive for acid-fast bacilli (AFB) without tuberculosis DNA. The preliminary diagnosis was of a non-tuberculosis infection that progressed slowly, and the CXR showed the condition to worsen daily. Four years later, a commercialized mycobacteria growth indicator tube system was used to culture the colonies of AFB successfully in liquid medium, and the species Mycobacterium heckeshornense was identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. The patient responded well to triple therapy with rifampicin, ethambutol, and clarithromycin, the sputum cultures remained negative and the roentgenogram showed minor improvement over the following 6 months.

Metastatic pulmonary calcification: First report of pulmonary calcium suppression using dual-energy CT

Metastatic pulmonary calcification is an underdiagnosed metabolic lung disease characterized by diffuse calcium deposition in the lungs, often associated with secondary hyperparathyroidism due to chronic renal failure. A 31-year-old man with chronic renal failure initially presented with diffuse pain symptoms, deterioration of general condition, and respiratory insufficiency. Noncontrast-enhanced computed tomography of the chest was performed using a spectral-detector-based dual-energy CT. It showed multiple, centrilobular, ground-glass opacities, and nodules, ultimately leading to the diagnosis. Calcium suppression proved to be highly useful to classify the pulmonary alterations.

CTPA with a conventional CT at 100 kVp vs. a spectral-detector CT at 120 kVp: Comparison of radiation exposure, diagnostic performance and image quality

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With SD-CT, increased radiation exposure is not present.

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In the current study, CTDI_vol was lower with SD-CT than with C-CT, even when 100 kVp was used for the latter.

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With SD-CT, higher levels of diagnostic performance and image quality can be achieved.

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SD-CT may be the system of choice due to the availability of spectral data and thus additional image information.

Purpose

To compare CT pulmonary angiographies (CTPAs) as well as phantom scans obtained at 100 kVp with a conventional CT (C-CT) to virtual monochromatic images (VMI) obtained with a spectral detector CT (SD-CT) at equivalent dose levels as well as to compare the radiation exposure of both systems.

Material and Methods

In total, 2110 patients with suspected pulmonary embolism (PE) were examined with both systems. For each system (C-CT and SD-CT), imaging data of 30 patients with the same mean CT dose index (4.85 mGy) was used for the reader study. C-CT was performed with 100 kVp and SD-CT was performed with 120 kVp; for SD-CT, virtual monochromatic images (VMI) with 40, 60 and 70 keV were calculated. All datasets were evaluated by three blinded radiologists regarding image quality, diagnostic confidence and diagnostic performance (sensitivity, specificity). Contrast-to-noise ratio (CNR) for different iodine concentrations was evaluated in a phantom study.

Results

CNR was significantly higher with VMI at 40 keV compared to all other datasets. Subjective image quality as well as sensitivity and specificity showed the highest values with VMI at 60 keV and 70 keV. Hereby, a significant difference to 100 kVp (C-CT) was found for image quality. The highest sensitivity was found using VMI at 60 keV with a sensitivity of more than 97 % for all localizations of PE. For diagnostic confidence and subjective contrast, highest values were found with VMI at 40 keV.

Conclusion

Higher levels of diagnostic performance and image quality were achieved for CPTAs with SD-CT compared to C-CT given similar dose levels. In the clinical setting SD-CT may be the modality of choice as additional spectral information can be obtained.

A Recovered Case of COVID-19 Myocarditis and ARDS Treated With Corticosteroids, Tocilizumab, and Experimental AT-001

We describes a case of a critically ill patient with myocarditis and severe acute respiratory distress syndrome related to coronavirus disease-2019. This case highlights management strategies, including the use of corticosteroids, an interleukin-6 inhibitor, and an aldose reductase inhibitor, resulting in complete clinical recovery. (Level of Difficulty: Intermediate.)

RADIANCE - Radiochemotherapy with or without Durvalumab in the treatment of anal squamous cell carcinoma: A randomized multicenter phase II trial

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The 3-year disease-free survival of locally-advanced anal carcinoma is about 60%.

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Anal carcinoma is considered an immunogenic tumor due to its association with HPV.

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The PD-L1 inhibitor durvalumab may synergize with radiochemotherapy.

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The RADIANCE trial will test durvalumab with radiochemotherapy in anal carcinoma.

Purpose

Anal squamous cell carcinomas (ASCC) are increasing in frequency across the developed world. The 3-year disease-free survival (DFS) in patients with locally-advanced disease is approximately 60% after primary radiochemotherapy (RCT). There is a strong rationale for combining immunotherapy with RCT in patients with ASCC due to its association with human papilloma virus (HPV) infection.

Methods/design

RADIANCE is an investigator initiated, prospective, multicenter, randomized phase II trial testing the addition of Durvalumab, a PD-L1 immune checkpoint inhibitor, to standard RCT in 178 patients with locally advanced ASCC (T2 ≥ 4 cm Nany, cT3-4 and/or cN+). In the control arm, patients will be treated with standard mitomycin C (MMC)/5-fluorouracil (5-FU)-based RCT. Intensity-modulated radiotherapy (IMRT) will be applied as follows: PTV_A (primary tumor) T1-T2 < 4 cm N+: 28 × 1.9 Gy = 53.2 Gy; or T2 ≥ 4 cm, T3-4 Nany: 31 × 1.9 Gy = 58.9 Gy; PTV_N (involved node): 28 × 1.8 Gy = 50.4 Gy ; and PTV_Elec (elective node): 28 × 1.43 Gy = 40.0 Gy over a period of 5,5–6 weeks. Concomitant chemotherapy will be administered using MMC with 5-FU during weeks 1 and 5 of radiotherapy (MMC 12 mg/m², day 1 [maximum single dose 20 mg]; 5-FU 1000 mg/m² days 1–4 and 29–32). In the experimental arm, Durvalmab (1500 mg absolute dose, intravenously) will be combined with the same RCT as in the control arm. Immunotherapy with Durvalumab will start 14 days before initiation of standard RCT, administered every four weeks (q4w) thereafter for a total of twelve doses. The primary endpoint is disease-free survival (DFS) after 3 years.

Discussion

As ASCC is considered an immunogenically “hot” tumor due to its association with HPV infection, the combination of RCT with Durvalumab may improve tumor control and long-term clinical outcome in this patient collective compared to RCT alone.

Microcatheter injection reduces the amount of contrast medium during middle cerebral artery aneurysm embolization in a patient with chronic kidney disease

We describe a unique technique to reduce the amount of contrast medium by injecting diluted contrast medium from the microcatheter during neurointervention. A patient with severe renal impairment due to polycystic kidney was referred for endovascular surgery for wide-neck middle cerebral artery aneurysm. In order to reduce the amount of contrast medium, contrast medium was injected from the microcatheter placed in the middle cerebral artery during coil embolization; renal function decline was not observed after the procedure. This technique, therefore, reduces the amount of contrast medium and enables one to perform coil embolization safely.

A Rare Complication of Chronic Active Epstein-Barr Virus Infection

A 42-year-old man with a 6-month-long fever was found to have chronic active Epstein-Barr virus infection complicated by aneurysmal coronary arteries with other arteries. In adult patients with this infection, coronary aneurysms are rare but are a poor prognostic factor. (Level of Difficulty: Intermediate.)

An atypical complicated left-sided bronchopleural fistula presenting more than seven months after lobectomy

Background

Bronchopleural fistulas (BPF) are abnormal sinus tracts connecting the bronchi and pleural cavity and form after surgical resection of a lung lobe. It is a complication with potentially disastrous sequelae including, failure of the bronchial stump to heal, ischemia of the affected area, and/or infection of the stump. Bronchopleural fistulas caused by surgical intervention most commonly present on the right side and within 7–12 days post-operatively, i.e., subacutely. While the fistula may initially be asymptomatic, they carry a mortality rate of 25–71% in the absence of other comorbidities.

Case presentation

A 60-year-old female developed a BPF more than seven months after a left lower lobe lung lobectomy for non-small cell adenocarcinoma is presented. She was seen at our hospital on multiple occasions after her lobectomy with no evidence of a developing fistula on chest computer tomography (CT) during those visits. During her most recent presentation, roughly 7 months postoperatively, she was noted on imaging to have a new left-sided bronchopleural fistula. Bronchoscopy with lavage and culture of the fistula grew Pseudomonas Aeruginosa, for which she received appropriate treatment. Further surgical interventions were deferred due to poor prognosis. Her presentation differed from the typical BPF presentation in that it was left-sided and occurred out of the window of its usual occurrence.

Conclusion

Late-onset BPF is an important diagnosis to consider in patients who have undergone lung resection, regardless of the type of surgery or postoperative duration, especially when patients are known to have multiple predisposing factors.

A rare case of giant cystic adamantinomatous craniopharyngioma in an adult

Craniopharyngioma is an uncommon intracranial tumor that primarily occurs in the sella turcica. Giant cystic craniopharyngioma is rare in general and extremely rare in adults. We report a rare case of giant cystic craniopharyngioma in the anterior pontine cisterna and suprasellar cisterna. A 27-year-old man presented with double vision, and craniocerebral MRI revealed cystic masses in the anterior pontine cisterna and suprasellar cisterna. The masses were removed surgically and diagnosed as large cystic craniopharyngiomas by pathology and MRI. Giant cystic craniopharyngioma is rare in adults. Through this case report, we hope to increase awareness of this disease among various clinicians, including radiologists.

Endovascular exclusion of the entire aortic arch with branched stent-grafts after surgery for acute type A aortic dissection

Background

The treatment of residual pathology of the aortic arch after surgical repair for type A acute dissection (AAD) represents a therapeutic challenge. Recently, new branched endovascular devices have expanded the possibility of aortic arch stent-grafting (ASG) with proximal landing in zone 0. The aim of this retrospective, single-center study was to evaluate outcomes of patients with a history of surgical repair for AAD undergoing ASG with branched devices.

Methods

We analyzed patients undergoing ASG after treatment for type AAD with 2 different branched devices: Nexus (dual-module, single branch, off-the-shelf) and RelayBranch (single-module, dual branch, custom-made). Before ASG, surgical bypass of supra-aortic vessels was performed according to patient's anatomy and to the selected device. All patients underwent clinical and computed tomography scan evaluation before hospital discharge, at 6 months, and on a yearly basis thereafter.

Results

From March 2017 to April 2019, 4 consecutive patients underwent ASG after surgery for AAD at our institution. Mean time from surgery for AAD to ASG was 20 months. Mean age at the time of ASG was 72 years. Nexus and Relay were implanted in 2 patients each. All patients survived and were successfully discharged. Mean intensive care unit stay and hospital stay were 3 and 19 days, respectively. We did not observe any major adverse events. At a mean follow-up of 28 months, all patients are alive and computed tomography scans showed good anatomic results with no endoleaks.

Conclusions

This preliminary experience shows that ASG after surgery for AAD is feasible and provides encouraging clinical and anatomic early results.

Transient receptor potential vanilloid 1 and 4 double knockout leads to increased bone mass in mice

Calcium balance is important in bone homeostasis. The transient receptor potential vanilloid (TRPV) channel is a nonselective cation channel permeable to calcium and is activated by various physiological and pharmacological stimuli. TRPV1 and TRPV4, in particular, have important roles in intracellular Ca²⁺ signaling and extracellular calcium homeostasis in bone cells. TRPV1 and TRPV4 separately mediate osteoclast and osteoblast differentiation, and deficiency in any of these channels leads to increased bone mass. However, it remains unknown whether bone mass increases in the absence of both TRPV1 and TRPV4. In this study, we used TRPV1 and TRPV4 double knockout (DKO) mice to evaluate their bone mass in vivo, and osteoclast and osteoblast differentiation in vitro. Our results showed that DKO mice and wild type (WT) mice had no significant difference in body weight and femur length. However, the results of dual-energy X-ray absorption, microcomputed tomography, and bone histomorphometry clearly showed that DKO mice had higher bone mass than WT mice. Furthermore, DKO mice had less multinucleated osteoclasts and had lower bone resorption. In addition, the results of cell culture using flushed bone marrow from mouse femurs and tibias showed that osteoclast differentiation was suppressed, whereas osteoblast differentiation was promoted in DKO mice. In conclusion, our results suggest that the increase in bone mass in DKO mice was induced not only by the suppression of osteoclast differentiation and activity but also by the augmentation of osteoblast differentiation and activity. Our findings reveal that both the single deficiency of TRPVs and the concurrent deficiency of TRPVs result in an increase in bone mass. Furthermore, our data showed that DKO mice and single KO mice had varying approaches to osteoclast and osteoblast differentiation in vitro, and therefore, it is important to conduct further studies on TRPVs regarding the increase in bone mass to explore not only individual but also a combination of TRPVs.

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Knockout of either TRPV1 or TRPV4 results in increased bone mass in mice.

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This study evaluates the effects of TRPV1 and TRPV4 double knockout (DKO) in mice.

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Concurrent TRPV1 and TRPV4 deficiency increases mouse bone mass.

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TRPV1 and TRPV4 DKO suppresses osteoclast differentiation and activity.

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TRPV1 and TRPV4 DKO enhances osteoblast differentiation and activity.

Rapid and sustained effects of a single dose of benralizumab on chronic eosinophilic pneumonia

Chronic eosinophilic pneumonia (CEP) is an eosinophilic inflammatory disease of unknown etiology, and oral corticosteroid (OCS) is commonly used for its treatment. Approximately half of CEP cases relapse secondary to reduction or termination of OCS. A 43-year-old woman visited our hospital because of a chronic cough and abnormal chest X-ray findings. She was diagnosed with CEP because of marked eosinophilia, as well as eosinophilic infiltrates in cryobiopsy samples. After initiation of OCS treatment, her symptoms disappeared with a decrease in peripheral blood eosinophil counts and the amelioration of abnormal infiltrative shadows on chest X-ray. However, symptoms reappeared after OCS termination, including a recurrence of eosinophilia and appearance of fresh abnormal shadows on chest X-ray. Because she refused readministration of OCS because of side effects such as appetite enhancement and moon face in last treatment course, we administered her a single dose of benralizumab. Her symptoms and peripheral eosinophil counts were markedly ameliorated 1 week after benralizumab administration. The marked amelioration in abnormal shadows on chest X-ray were maintained 2 weeks after benralizumab administration. She had no relapse of CEP for almost 6 months after benralizumab administration. Our experience with this case suggests that a single dose of benralizumab may be a treatment option for relapsed CEP cases or those with side effects of long-term OCS therapy.

A case report of an unrecognized osteoid osteoma of the proximal femur

We present the case of a 59-year-old male patient with unrecognized osteoid osteoma in radiography as well as in magnetic resonance imaging. Computed tomography revealed osteoid osteoma that was successfully treated with percutaneous computed tomography guided radiofrequency ablation. The osseous pathology was underestimated on magnetic resonance imaging in the presented case and bone marrow edema led to incorrect diagnosis. The particular case emphasizes the value of computed tomography scans diagnosing an osteoid osteoma.

A fight-and-flight for life: A rare case of advanced cervical cancer in pregnancy

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Advanced cervical cancer during pregnancy requires shared decision making and a multidisciplinary team approach.

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If the pregnancy is continued, antepartum chemotherapy should be strongly considered.

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Maternal prognoses tend to be poor, but neonatal outcomes appear to be favorable.

Background

Advanced cervical cancer during pregnancy is an extremely rare event. We describe a case of at least stage IIIB cervical squamous cell carcinoma during pregnancy. This may possibly represent the longest gestation from time of diagnosis to delivery in a case of advanced cervical cancer, with potentially the most advanced gestational age at delivery and a relatively favorable outcome in the current literature.

Case: A 29-year-old female at 20 0/7 weeks of gestation with at least stage IIIB squamous cell carcinoma of the cervix flew from Micronesia to Hawaii for oncologic treatment. After consultation with gynecologic oncology and maternal-fetal medicine, she opted to continue the pregnancy and began neoadjuvant chemotherapy with carboplatin and paclitaxel. At 33 2/7 weeks of gestation, she was admitted for preterm prelabor rupture of membranes and immediately underwent a cesarean delivery for heavy vaginal bleeding. Postpartum, she underwent cisplatin chemotherapy with concurrent radiation therapy. After 6 cycles of chemotherapy, the patient’s cancer had progressed to the point that hospice was recommended. She died 11 months after initial presentation.

Conclusion

Advanced cervical cancer during pregnancy requires individualized treatment, shared decision making, and a multidisciplinary team approach. If the pregnancy is continued, antepartum chemotherapy should be strongly considered. Maternal prognoses tend to be poor, but neonatal outcomes appear to be favorable.

A case report of COVID-19 with false negative RT-PCR test: necessity of chest CT

The definite diagnosis of corona virus disease 2019 (COVID-19) is based on the viral isolation or positive result of polymerase chain reaction (PCR) from sputum, or nasal swab, or throat swab. However, the sensitivity to detect COVID-19 of real time (RT)-PCR is reported to be lower than that of chest CT. We report a case of 34-year-old man who was diagnosed as negative for COVID-19 based on the four sequential RT-PCR tests of his pharyngeal swab. Chest CT showed patchy ground-glass opacity on admission, and it rapidly progressed to segmental mixed consolidation and ground-glass opacity 3 days after admission, and it resolved in left upper lobe, but showed multifocal ground-glass opacities 7 days after admission, and they resolved within 2 weeks. The fifth RT-PCR test finally revealed positive results at the fifth day after admission. It is difficult to distinguish COVID-19 pneumonia from other viral pneumonia on CT findings alone; however, we emphasize the utility of chest CT to detect early change of COVID-19 in cases which RT-PCR tests show negative results.

Intraoperative evaluation of hepatic artery blood flow during pancreatoduodenectomy (HEPARFLOW): Protocol of an exploratory study

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Assessment of flow rates of the hepatic artery during pancreatoduodenectomy.

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Identification of pre- and intraoperative factors influencing liver blood flow.

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Relevance of a celiac axis stenosis by pancreatoduodenectomy.

Introduction

Pancreatoduodenectomy is the treatment of choice for a range of benign and malignant diseases. The pancreatic head must be separated from its supplying vessels, especially the gastroduodenal artery, during this operation. However, dissection of the gastroduodenal artery can disturb blood supply to the liver and result in liver ischemia. There is currently no well-established algorithm to evaluate and ensure sufficient blood flow in patients with altered hepatic artery blood flow. To address this important issue, this study aims to establish a basis for assessing liver blood supply during pancreatoduodenectomy. Furthermore, factors influencing arterial blood flow and related postoperative complications will be evaluated.

Methods and analysis

The HEPARFLOW study is a single institutional single-arm prospective exploratory observational clinical trial. All consecutive patients undergoing elective partial or total pancreatoduodenectomy will be screened for inclusion until 100 patients are enrolled. Blood flow in the proper hepatic artery, gastroduodenal artery, portal vein, and additional vessels supplying the liver will be measured during pancreatoduodenectomy using Doppler flowmetry. All patients will be followed up for 90 days after surgery. At each visit, standard clinical data, postoperative complications and mortality will be recorded.

Discussion

This will be the first study to prospectively assess intraoperative flow rates of the hepatic artery and portal vein to evaluate liver blood supply during pancreatoduodenectomy. The preoperative and intraoperative factors influencing blood flow in the hepatic arteries will be identified. This study may also reveal the hemodynamic and clinical relevance of a compression of the celiac axis during pancreatoduodenectomy.

Ethics and dissemination

This study was approved by the Ethics Committee of the University of Heidelberg (S-073/2018). The results will be published in a peer-reviewed journal and will be presented at medical meetings.

Pancreatic metastasis from locally recurrent neuroendocrine differentiated prostate cancer after radical prostatectomy

Pancreatic metastasis from prostate cancer (PC) is quite rare. Herein, we report the case of a 67-year-old man with pancreatic metastasis from a neuroendocrine differentiated PC (NEDPC), a local recurrence after radical prostatectomy and androgen deprivation therapy for 6 years. Chemoradiotherapy was initiated for the locally recurrent NEDPC, and it had almost disappeared after the therapy. However, rapidly enlarged pancreatic metastasis from the NEDPC was detected 6 months after therapy. There is no standard treatment available for pancreatic metastasis from NEDPC owing to its rarity; hence, further knowledge and clinical experience regarding it are crucial.

Late Atrial Thrombus Formation After Percutaneous Patent Foramen Ovale Closure

Late thrombus formation is a rare complication associated with patent foramen ovale (PFO) closure devices. We report the case of an incidental discovery of large thrombi in both atria 9 months after percutaneous PFO occlusion that required cardiac surgery for thrombi removal. (Level of Difficulty: Beginner.)