Imaging in pulmonary hydatid cysts

Magnetic resonance imaging features and classification of intraspinal echinococcosis

Objective

This study aimed to investigate the magnetic resonance imaging (MRI) features and classification of echinococcosis of the spinal canal.

Methods

The clinical manifestations and MRI findings and classification of 19 patients diagnosed with intraspinal echinococcosis over 10 years (2011-2020) were retrospectively analyzed.

Results

The mean age of the nine males and 10 females was 39 years (range 28-65 years). Among these, the number of cases with thoracic, lumbar, sacral, thoracolumbar, and lumbosacral, cervical, and lumbar segments was nine (47 %), five (26 %), one (5 %), one (5 %), two (11 %), and one (5 %) cases, respectively. Furthermore, 13 cases (69 %) involved adjacent vertebral bodies, accessories, and surrounding soft tissues. The lesion was confined to the intramedullary, extramedullary subdural, extramedullary epidural, and multiple spaces in one (Type I) (5 %), four (Type II) (21 %), one (Type III) (5 %), and thirteen (69 %) cases, respectively. Moreover, nine cases (47 %) had a history of hydatid disease in the spine or other tissues. The clinical manifestations were chest and lumbosacral pain in 18 cases (95 %) and chest and lumbosacral pain accompanied by lower limb dysfunction in four cases (21 %). The MRI revealed different sizes of T1WI low-signal and T2WI high-signal vesicles with a "grape-like" appearance, with 16 cases (84 %) showing low signals on the edge of the cyst wall.

Conclusion

Intraspinal echinococcosis is rare, even in endemic areas. However, intraspinal echinococcosis should be considered when there is a history of echinococcosis in other sites or when there are clear MRI characteristics for the disease.

Unusual pediatric lung infections: imaging findings

Pediatric lung infections continue to be a leading cause of pediatric morbidity and mortality. Although both pediatric and general radiologists are familiar with typical lung infections and their imaging findings in children, relatively rare lung infections continue to present a diagnostic challenge. In addition, the advances in radiological imaging and emergence of several new lung infections in recent years facilitated the need for up-to-date knowledge on this topic. In this review article, we discuss the imaging findings of pediatric lung infections caused by unusual/uncommon and new pathogens. We review the epidemiological, clinical, and radiological imaging findings of viral (coronavirus disease 2019, Middle East respiratory syndrome, bird flu), bacterial (Streptococcus anginosus, Francisella tularensis, Chlamydia psittaci), and parasitic lung infections (echinococcosis, paragonimiasis, amoebiasis). Additional disorders whose clinical course and imaging findings may mimic lung infections in children (hypersensitivity pneumonitis, pulmonary hemorrhage, eosinophilic pneumonia) are also presented, to aid in differential diagnosis. As the clinical presentation of children with new and unusual lung infections is often non-specific, imaging evaluation plays an important role in initial detection, follow-up for disease progression, and assessment of potential complications.

Primary extrahepatic hydatid cyst of the thigh, an unusual presentation of sciatica: A case report of a diagnostic challenge

INTRODUCTION

Sciatica, a condition characterized by pain along the sciatic nerve distribution, is commonly associated with nerve compression or irritation. However, its etiology can vary, including rare non-spinal causes such as hydatid cysts. We present a case of hydatid cyst in the thigh causing sciatica-like symptoms, highlighting the diagnostic challenges and management approach.

CASE PRESENTATION

A 40-year-old patient with a history of pulmonary tuberculosis presented with persistent lumbosciatic pain despite conservative treatment. Physical examination revealed left sciatica without spinal abnormalities. MRI revealed a hydatid cyst in the thigh, causing nerve irritation. Surgical resection of the cyst was performed, achieving symptom resolution.

DISCUSSION

Hydatid cysts in skeletal muscles are rare, with atypical presentations complicating diagnosis. Localization in the thigh, particularly the biceps femoris muscle, is uncommon. Diagnostic modalities include imaging and serological tests, while treatment involves surgical excision and postoperative albendazole therapy.

CONCLUSION

Recognition of rare presentations like thigh hydatid cysts causing sciatica-like symptoms is crucial for timely diagnosis and management. This case emphasizes the importance of considering unusual etiologies in refractory sciatica cases and underscores the complexity of medical diagnosis. Increased awareness among healthcare providers can lead to improved patient outcomes and prevent diagnostic delays.

Primary Pulmonary Echinococcosis in the United States: A Case Report and Review of the Literature

We depict a unique case of a 34-year-old woman who presents to the emergency department with complaints of dyspnea and chest pain for the past month. A chest x-ray (CXR) from an earlier urgent care visit was concerning for large fluid opacity in the left lung and follow-up imaging revealed a cystic mass suspicious of a pulmonary cystic abscess. The patient underwent complete lobectomy and resection. Post-surgical biopsy confirmed pulmonary hydatid cystic mass and signs of rupture or seeding to liver tissue. The patient was discharged with adjuvant therapy and recommended imaging follow-up for the next decade. The diagnosis, treatment, and maintenance guidelines are discussed in this report which reveals controversy between experts given the lack of complete literature regarding echinococcosis. Our purpose in putting forward this case is to present a rare diagnosis of pulmonary echinococcosis in the United States and to emphasize the importance of early imaging and diagnosis to prevent cystic rupture and secondary organ dissemination.

Challenges and Prospective of Enhancing Hydatid Cyst Chemotherapy by Nanotechnology and the Future of Nanobiosensors for Diagnosis

Hydatid cysts have been widely recognized for decades as a common medical problem that affects millions of people. A revolution in medical treatment may be on the prospect of nanotechnology enhancing chemotherapy against hydatid cysts. An overview of nanotechnology's impact on chemotherapeutics is presented in the current review. It discusses some of the challenges as well as some of the opportunities. The application of nanotechnology to enhance chemotherapy against hydatid cysts is what this review will explore. Nanotechnology is a critical component of delivering therapeutic agents with greater precision and efficiency and targeting hydatid cysts with better efficacy, and minimizing interference with surrounding tissue. However, there are biodistribution challenges, toxicity, and resistance problems associated with nanotherapeutics. Additionally, nanobiosensors are being investigated to enable the early diagnosis of hydatid cysts. A nanobiosensor can detect hydatid cysts by catching them early, non-invasively, rapidly, and accurately. The sensitivity and specificity of diagnostic tests can be enhanced with nanobiosensors because they take advantage of the unique properties of nanomaterials. By providing more precise and customized treatment options for hydatid cysts, nanotechnology may improve therapeutic options and strategies for diagnosing the disease. In conclusion, treatment with nanotechnology to treat hydatid cysts is potentially effective but presents many obstacles. Furthermore, nanobiosensors are being integrated into diagnostic techniques, as well as helping to diagnose patients earlier and more accurately.

Cross-sectional imaging review of common to uncommon lung cancer mimickers in a tertiary care oncology center

Lung cancer is the most diagnosed cancer worldwide. Many non-malignant pulmonary lesions, such as tuberculosis, fungal infection, organizing pneumonia, inflammatory myofibroblastic tumor, and IgG4 disease, can mimic lung cancer due to their overlapping morphological appearance on imaging. These benign entities with minor differentiating imaging clues may go unnoticed in a high-volume cancer institution, leading to over-investigation that may result in repeated biopsies, pointless wedge resections, and related morbidities. However, with a thorough medical history, laboratory diagnostic work-up, and careful analysis of imaging findings, one can occasionally restrict the range of possible diagnoses or arrive at a definitive conclusion. When imaging features overlap, image-guided lung sampling is crucial since histopathological analysis is the gold standard.

Pulmonary Cystic Echinococcosis in a Child Presenting in the United Kingdom with Fever and Chest Pain: A Brief Report and Discussion on Management

Cystic echinococcosis is a zoonosis caused by the larvae of Echinococcus granulosus . Pulmonary disease may be asymptomatic until the cyst ruptures or becomes secondarily infected. We report a case of pulmonary cystic echinococcosis presenting in the United Kingdom, with discussion on management: optimum antihelminthic agent, length of treatment and type of operative intervention. Treatment should be individualized to the clinical scenario.

Traumatic occult pneumothorax and ipsilateral hydatid cyst: A case report

INTRODUCTION

Traumatic pneumothorax is a common chest condition that can be caused by a chest trauma. Hydatid cysts are also common, especially in Syria, and is caused by Echinococcus granulosis infection.

CASE PRESENTATION

We report a case of mutual presentation of pneumothorax and a large Hydatid cyst on the same chest side in an 18 years-old patient who got stabbed in the chest. The chest x-ray reveled well-defined, homogeneous radio-opacity lesion that is consistent with Hydatid cyst but no pneumothorax was observed. Later, the chest CT showed a small pneumothorax that coexist with the Hydatid cyst. The case was treated conservatively and the patient survived.

DISCUSSION

Some studies support treating asymptomatic trauma patients with occult PT with observation and placing a chest tube if still asymptomatic. Our case questions the management protocol for such a rare encounter as the stability status of the patient was poor, and there was a large hydatid cyst close to the chest wall.

CONCLUSION

Physicians should be aware of the possible management solutions when dealing with similar cases, especially in emergency settings. Until clear guidelines are published for this matter, we recommend that high-level observation of the patient's vitals are the determining factor for suitable intervention.

An unexpected guest: Pulmonary echinococcosis diagnosed by intraoperative frozen section examination. A case report and literature review

Echinococcosis is caused by tapeworms belonging to the Echinococcus genus. The most common site of infection is the liver although it may involve almost any organ. Symptoms of pulmonary echinococcosis vary depending on the location and structure of the cyst. While uncomplicated cysts usually appear at imaging as well-defined homogeneous lesions with fluid content and smooth walls of variable thickness, complicated lesions may have a more heterogeneous content with higher density making more difficult the distinction from malignancies or other infections. Hereby we describe the case of a 61-year-old Northern African male admitted to our tertiary center for left upper chest pain who then underwent a chest computed tomography (CT) scan which demonstrated a large hypodense lesion, with smooth and thick walls, in the upper left lobe. The following magnetic resonance confirmed the homogeneous fluid content, and the 18 F- fluorodeoxyglucose-positron emission tomography/CT demonstrated a mild uptake of the walls. According to these findings, the main differential diagnoses at imaging included bronchogenic cyst, synovial sarcoma, and pulmonary hematoma although the patient denied any recent trauma. Given the large size and clinical symptoms he underwent surgery. Intra-operative frozen section, supported by imprint cytology, excluded the presence of malignancy while suggested an echinococcal laminar exocyst. The final pathological examination confirmed the diagnosis of echinococcosis (i.e., Echinococcus Granulosus protoscolex). After surgery he was treated with albendazole and at the six-month follow-up he was in good clinical conditions. Our case highlights the importance of considering rare infections, particularly in individuals from endemic areas. Frozen tissue analyses can be a diagnostic challenge and often require ancillary tools such as imprint cytology and serial sections for more sensitive and accurate diagnosis.

Tension Hydropneumothorax Caused by a Ruptured Hydatic Cyst in the Pleural Cavity: Case Report

Hydatid disease is a zoonosis caused by a larva of the tapeworm Echinococcus. All organs can be involved, but it is frequently located in liver for adults and lung for children. The clinical features are nonspecific. Imaging findings has an important place in the diagnosis and the follow-up. Rupture is the most common complication of a hydatic cyst and has a variety of imaging findings depending on the ruptured layer, the amount of air within the cyst and the type rupture. We report the case of a 10-year-old boy presenting shortness of breath and fever among other symptoms revealing by chest X-ray and thoracic CT scan, a lung ruptured hydatic cyst to the pleural cavity causing a tension hydro-pneumothorax and a superadded infection.

The Neoplasms Mimicker: A Pictorial Review of Hydatid Disease

Hydatid cyst is a common name for the larval stage of a tapeworm species of the genus Echinococcus granulosus, which is transmitted from animals to humans via the fecal–oral route. Hydatid cysts predominantly affect the liver (75%), followed by the lung (15%), and they can affect many organs in the human body. Medical imaging modalities are the keystone for the diagnosis of hydatid cysts with high sensitivity and specificity. Ultrasound imaging with high resolution is the first choice for diagnosis, differential diagnosis, staging, establishing a role in interventional management, and follow-up, and it can differentiate Type I hydatid cysts from simple liver cysts. Unenhanced computed tomography (CT) is indicated where or when an ultrasound is unsatisfactory, such as with chest or brain hydatid cysts, when detecting calcification, and in obese patients. Magnetic resonance imaging (MRI) is superior for demonstrating cyst wall defects, biliary communication, neural involvement, and differentiating hydatid cysts from simple cysts using diffusion-weighted imaging (DWI) sequences. According to the phase of growth, hydatid cysts occur in different sizes and shapes, which may mimic benign or malignant neoplasms and may create diagnostic challenges in some cases. Hydatid cysts can mimic simple cysts, choledochal cysts, Caroli’s disease, or mesenchymal hamartomas of the liver. They can mimic lung cystic lesions, mycetoma, blood clots, Rasmussen aneurysms, and even lung carcinomas. Differential diagnosis can be difficult for arachnoid cysts, porencephalic cysts, pyogenic abscesses, and even cystic tumors of the brain, and can create diagnostic dilemmas in the musculoskeletal system.

Proteomics investigation of human sera for determination of postoperative indicators of pulmonary cystic echinococcosis

BACKGROUND

Cystic echinococcosis (CE)/hydatidosis is an important zoonotic parasitic disease caused by the larval stage of Echinococcus granulosus. The disease is a major health problem all over the world. Finding specific and sensitive biomarkers for follow-up of CE in patients after surgery is essential. Using proteomics methods, the present study aimed to evaluate post-surgical treatment by finding probable biomarker/s in the serum of human lungs CE.

METHODS

A total of 24 human sera were tested. These sera included eight confirmed lung/s CE patients sera before surgery (BS), eight sera 12 months post-surgery (12MPS) as well as eight control sera from healthy people. Proteomics methods including 2DE and LC-MS/MS were performed on the specimens followed by bioinformatics analysis. Differentially expressed proteins (DEP) were detected and, separately integrated with protein-protein interaction (PPI) data to construct the PPI network.

RESULTS

A total of 171 protein spots were detected in three groups including BS, 12MPS, and control groups; of which a total of 106 DEP have been expressed based on fold changes > = 2 and p-value < 0.05. More analysis was performed and a total of 10 protein spots were selected for identification by mass spectrometry showing the following proteins: APOA1, BGN, SPP2, EAF1, ACOXL, MRPL55, MCTP2, SEPTIN1, B4GALNT1, and ZNF843. Based on centrality parameters of the PPI network (degree and betweenness) five Hub-bottlenecks proteins with significant centrality values were found including APOA1, BGN, SPP2, EAF1, and ACOXL.

CONCLUSION

This study showed five proteins as hub-bottleneck proteins; of which APOA1 was more prominent. It can be concluded that a change in expression of this protein in patients' sera could be used as an indicator tool for the achievement of lungs CE surgical therapy.

Parasitic lung diseases

Parasitic lung diseases are caused by a number of parasites as a result of transient passage in the lung or as a result of an immunologic reaction. The clinical presentation may be in the form of focal or cystic lesions, pleural effusion or diffuse pulmonary infiltrates. With increasing globalisation, it is important to consider parasitic infections in the differential diagnosis of lung diseases. This is particularly important since early identification and prompt therapy result in full cure of these conditions. In this review, we summarise the most common parasitic lung diseases.

Pulmonary Hydatid Cyst in Children and Adults: Diagnosis and Management

Hydatid cyst disease induced by Echinococcus granulosus is a parasitic disease known since ancient times. Today, it continues to be seen in many countries and creates serious problems. The lung is the second most frequently affected organ by hydatid cysts after the liver. Lung involvement is more prevalent in children than adults, and the growth of the cyst is faster in children. Hydatid cysts are mostly seen in the right lower lobe of the lung. Common symptoms are chest pain, cough, and shortness of breath, with the most diagnostic symptom being the expectoration of cyst fluid or membranes. In endemic areas, the diagnosis of hydatid cysts can usually be made easily by clinical findings, serology tests, and radiological findings. When the hydatid cyst ruptures and becomes complicated, it is clinically and radiologically confused with many diseases, especially lung cancer. Surgery is accepted as primary treatment of lung hydatid cysts all over the world. The surgical approach is related to several factors such as the size of the cyst, whether it is intact or complicated, unilateral or bilateral, solitary or multiple, and the presence of destruction of the lung parenchyma. Although it is stated by some surgeons that capitonnage is not required, the most frequently applied surgical technique is cystotomy and capitonnage. Pulmonary resection should be avoided as much as possible, particularly in children. Albendazole or mebendazole treatment in pulmonary hydatid cyst is generally used after surgery and to prevent recurrences.

Pitfalls in the surgical treatment of undiagnosed lung lesions and cystic pulmonary hydatidosis

Background

Hydatid cysts can mimic many lung pathologies radiologically, as well as some malignant or benign lung tumors may show hydatid cyst-like radiological features. The aim of our study is to present our clinical experience and recommendations by analyzing the cases that create diagnostic difficulties by presenting a common radiological pattern with a pulmonary hydatid cyst.

Methods

The patients who were operated on with a preliminary diagnosis of hydatid cyst but were diagnosed differently, and who were operated on with different prediagnoses and unexpectedly diagnosed with hydatid cyst were included in the study. The clinical and radiological features of the patients were documented, and the features of the cases that could cause difficulties in diagnosis and treatment for the surgeon were revealed.

Results

A total of 20 patients who were radiologically suggestive of hydatid cyst but were diagnosed differently or unexpectedly diagnosed as hydatid cyst were included in the study. Lung cancer, bronchogenic cyst, or bronchiectasis were detected in 13 patients who were radiologically suggestive of hydatid cyst. There were 7 patients who were diagnosed with hydatid cysts, although they did not have specific radiological findings.

Conclusions

While hydatid cysts can mimic many lung pathologies, many benign or malign parenchymal lung pathologies may exhibit hydatid cyst-like radiological features. Therefore, in regions where a hydatid cyst is endemic, the surgeon should consider all possibilities while managing the cases.

Clinical registration number: Institutional Review Board of the Dr Suat Seren Chest Diseases and Chest Surgery Education and Research Center (No. 49109414-604.02).

Paediatric pulmonary echinococcosis: A neglected disease

Echinococcosis is a worldwide public health problem causing considerable paediatric morbidity and mortality in endemic areas. The presentation of cystic echinococcosis (CE) varies by age. Unlike adults, where hepatic involvement is common, pulmonary CE is the dominant site in the paediatric population. Pulmonary cysts are typically first seen on chest X-ray, either as an incidental finding or following respiratory symptoms after cyst rupture or secondary infection of the cyst. In children, pulmonary cysts have a broad differential diagnosis, and a definitive diagnosis relies on the combination of imaging, serology, and histology. In countries with high infectious burdens from diseases such as acquired immunodeficiency syndrome (AIDS) and tuberculosis (TB), the diagnosis is additionally challenging, as atypical infections are more common than in developed countries. Pulmonary CE is treated with a combination of surgery and chemotherapy.

Bilateral Large Pulmonary Hydatid Cyst: A Rare Presentation in a Young Child from Ethiopia

Hydatidosis is a parasitic disease caused by Echinococcus granulosus, which is endemic in many parts of the world. Hydatid cysts can occur in any organ of the human body and the lung is the most common site in children, primarily related to higher lung tissue elasticity. Bilateral pulmonary hydatid cyst is a rare clinical phenomenon in young children. Here, we report on a 3-year-old boy diagnosed with bilateral pulmonary hydatid cyst after he came with four months history of dry cough and progressive worsening of shortness of breath. Computed tomography of the chest revealed large bilateral thick-walled pulmonary cystic mass lesions, with bilateral perihilar extension and pressure effect on the diaphragm with surrounding atelectatic changes. The patient underwent left posterolateral thoracotomy and cyst excision was done for the left hydatid cyst. Two months after the first surgical cyst excision, right posterolateral thoracotomy and cystectomy was done for the right lung hydatid cyst. He recovered well post-operatively.

FDG PET/CT signs of proven pulmonary hydatid cyst: is there any clue?

PURPOSE

Pulmonary hydatid cyst (PHC) can imitate many diseases. Sometimes, positron emission tomography/computed tomography (PET/CT) is performed in terms of malignancy exclusion for complicated cysts. Although some specific findings (doughnut sign) have been identified in hydatid cyst of the liver, there is no specific sign described for PHC. The aim of this study is to investigate the presence of a common finding in PHC patients scanned with PET/CT inadvertently.

MATERIALS AND METHODS

From January 2015 to 2020, patients proven to have PHC were analyzed retrospectively. From all the patients, only 17, having a previous PET/CT, were included the study. Lesions were evaluated in three groups according to FDG uptake: A, negative; B, focal; C, doughnut sign.

RESULTS

The total number of patients was 17. Nine of the patients were male and the median age was 41.94 + 14.68 (16-65) years. SUV max of the lesions ranged from 0.5 to 15.8 (mean ± SE: 4.68). According to the FDG uptake of the lesions, five were in Group A, two in Group B, and the remaining ten (58.8%) in Group C with doughnut sign. To correlate the CT findings with PET/CT findings, doughnut sign, which is a typical finding of hydatid cysts of liver, is seen in only four patients in Group 1-classified cysts which are non-complicated. But in Group 2 (n = 3) and 3(n = 4), the finding of doughnut sign is three in both groups.

CONCLUSIONS

PET/CT is not a recommended imaging technique for PHC, but in cases where a definitive diagnosis is difficult, interpreting PET/CT findings is significant. This study demonstrates that previously described doughnut sign for liver hydatid cysts is also common for perforated pulmonary cysts. According to our knowledge, this is the first largest series of determining PET/CT findings of PHC. Further larger series will contribute to the literature.

A Multi-diagnostic Screening Study of the Prevalence and Risk Factors of Echinococcosis in First-degree Family Members of Infected Patients Undergoing Surgical Treatment

Background: Echinococcosis is a zoonotic infection caused by Echinococcus tapeworms. About 60% of patients remain asymptotic until severe stages. Early diagnosis of the infection in high-risk populations is of medical importance. Objectives: This study was designed to investigate the prevalence of echinococcosis among first-degree family members of the infected patients who underwent surgical treatment. Methods: A cross-sectional study was conducted to screen the first-degree family members of 96 patients who underwent surgical intervention at Imam Reza hospital, Mashhad, Iran, from September 2016 to March 2017. All family members were invited by phone calls to perform the serologic test, ultrasound examination, and chest X-ray test. Results: Forty-six (47.9%) patients participated in the study. A total of 114 family members performed the screening tests. Seven participants from five families (6.14%) were found to be infected in ultrasound examination (five females with a mean age of 36 years). There were no significant differences between the infected and non-infected groups concerning age (P = 0.921) and gender (P = 0.457). Conclusions: Screening the first-degree family members of patients with a confirmed echinococcosis infection results in the early diagnosis of infected patients, which is economically significant, especially in endemic areas.

Ultrasonography in the Evaluation of Pediatric Chest "Masses": When to Consider?

Thoracic ultrasound is radiation-free, easily available, portable modality with added advantage of real-time assessment. It is useful in mediastinal lesions and peripheral lung, pleural and chest wall masses. Not only is it a valuable modality in differentiating solid from cystic lesion, it can also depict internal architecture without the use of contrast material. The added advantages of its use in children are the lack of ionizing radiation, and no need for sedation or general anesthesia in most cases. Although it has its limitations with a longer learning curve, it can act as a second-line modality to chest radiograph and adjunctive modality to CT in cases of a thoracic mass in a child.

Bilateral Pulmonary Hydatid Cyst in a Young Child: A Rare Case Report from North India

Echinococcosis or hydatid disease is caused by the larval stage of the dog tapeworm, that is, Echinococcus granulosus , E. multilocularis , E. vogeli , or E. oligarthrus . Echinococcus granulosus causes cystic echinococcosis, which has a worldwide distribution. Liver is the most common site, affecting approximately two-third of the patients, whereas lung involvement is seen in approximately 25% of cases. This case is a very rare scenario of bilateral pulmonary hydatid cysts in a young child having exposure to a pet dog with negative hydatid serology and normal eosinophil count.

Cystic echinococcosis in a Moroccan boy: a silent and neglected disease among refugee and migrant children

We report the unusual case of a 5-year-old migrant boy from a rural area of Morocco with an almost-giant lung hydatid cyst that was an incidental finding on a chest X-ray performed during routine visa procedures. Echinococcus granulosus serology test was initially negative with subsequent positive seroconversion. Albendazole was started at 4 weeks before surgery and maintained for 4 months, with a favourable outcome. Cystic echinococcosis (CE) is considered a neglected tropical disease and affects more than one million people worldwide, mostly from a lower socioeconomic background. Preventive measures have been limited in underdeveloped regions. Children with CE are especially vulnerable, due not only to the high pathogenic potential of the disease but also to their frequent involvement in challenging socioeconomic situations, including migration. The incidence of CE is increasing in Europe because of high immigration flows from endemic countries. Nevertheless, CE is not covered by current migrant screening protocols.

Evaluation of clinical status, diagnosis, treatment and radiological findings of pulmonary hydatid cyst: 5-years' experience at tertiary lung center

BACKGROUND

Hydatidosis is one of the most critical worldwide parasitic zoonotic diseases. The lung is the second most common site of hydatidosis. This study aimed to evaluate the clinical status, diagnosis, treatment, and radiological findings of pulmonary hydatid cyst in patients referred to tertiary lung center.

METHODS

From April 2014 to July 2019, patients referred to Masih Daneshvari University Medical Center with the impression of alveolar hydatidosis included. Demographic data of 304 patients were collected including clinical symptoms, laboratory studies, radiological findings, location of the lung involvement, and cyst characteristics. Also, surgical procedures, medical treatments, and post-operative complications were recorded.

RESULTS

Pulmonary hydatidosis was confirmed for 234 patients. 55% of patients were males with the mean age of 45.1±16.6 years. The most common symptoms were cough (59.8%), dyspnea (31.1%), and hemoptysis (26%). Left lung, right lung, and bilateral involvement were reported in 40.1%, 55.1%, and 4.8% of cases, respectively. Cyst perforation (39.8%) was the most common intra-operative finding. Surgical interventions included thoracotomy, rigid bronchoscopy, cyst aspiration, and enucleation. The liver was the most concomitant organ involved due to pulmonary hydatidosis (16.6%). The most common postoperative complication was atelectasis, with the rate of 35.7%. 52.2% of patients were discharged within 10 days after surgery. No mortality was reported.

CONCLUSION

Sometimes atypical findings in different imaging modalities make the hydatid cyst diagnosis challenging. Although lobe involvement more than 50% has the indication for lobectomy, we conserved lobes with about 70% involvement in our institution, and patients had no postoperative complications.

Point-of-care Ultrasound Diagnosis of Pulmonary Hydatid Cyst Disease Causing Shock: A Case Report

Introduction

Point-of-care ultrasound (POCUS) is accepted as an important tool for evaluating patients presenting to the emergency department (ED) with dyspnea1 and undifferentiated shock.2 Identifying the etiology and type of shock is time-critical since treatments vary based on this information. Clinicians typically rely on the history, exam, and diagnostics tests to identify the etiology of shock. In resource-limited settings where there is reduced access to timely laboratory and diagnostic studies. The use of POCUS enables rapid classification and directed treatment of shock. Additionally, POCUS can aid in the diagnosis of rarer tropical diseases that can be important causes of shock in resource-limited settings.

Case Report

We discuss a case of a pediatric patient who presented to an ED in Cusco, Peru, with acute dyspnea and shock. Point-of-care ultrasound was used to expedite the diagnosis of a ruptured pulmonary hydatid cyst, guide proper management of septic and anaphylactic shock, and expedite definitive surgical intervention.

Conclusion

In resource-limited settings where there is reduced access to timely laboratory and diagnostic studies, the use of POCUS enables rapid classification and directed treatment of shock.

An Overview of Hepatic Echinococcosis and the Characteristic CT and MRI Imaging Manifestations

Hepatic echinococcosis is a parasitic, infectious disease with a high incidence in pastoral areas. It is highly infectious with a poor prognosis in some cases, which seriously affects the quality of life for people living in pastoral areas. This study aims to discuss the radiological characteristics, including computed tomography (CT) and magnetic resonance imaging (MRI), of hepatic echinococcosis from its definition, transmission, and pathological physiology. The characteristics of CT and MRI manifestations of cystic echinococcosis and alveolar echinococcosis are summarized in this study. It might help doctors to investigate this disease further and accurately make a diagnosis.

Single-stage versus two-stage surgery of pulmonary and hepatic hydatid cysts

Introduction

Concomitant lung and liver hydatid cyst is a rare condition. Most surgeons agree that both sites should be resected in one-time surgery.

Aim

We present a case series of hepatic and pulmonary hydatid cyst treated in one-stage surgery (OSS) compared with patients who underwent two-stage surgery (TSS).

Material and methods

This retrospective study included 47 patients separated into two groups (33 TSS and 14 OSS) between 2008 and 2019. Data on clinical symptoms, sites, radiological features, techniques, postoperative complications, mean hospital stay and outcome were analyzed separately for TSS and OSS procedures.

Results

A total of 33 patients who underwent TSS (70.2%) were compared to 14 patients operated on by OSS (29.8%). No significant differences were found between groups for age (45.3 vs. 42.7, p = 0.45), sex (male: 57.6% vs. 64.2%) and socio-geographic status (urban: 72.7% vs. 78.6%). But there were more postoperative complications (24.3% vs. 14.3%, p = 0.036) in the TSS group, and operative duration (154 minutes vs. 122 minutes, p = 0.047), postoperative hospital stay (13.8 days vs. 8.7 days, p = 0.022), and interruption of activities and work (56 days vs. 31 days, p = 0.045) were longer in the TSS group. There was no difference in postoperative mortality between the 2 groups.

Conclusions

Single-stage surgical management by trans-thoraco-phrenotomy can be recommended to treat dual-seat hepatic and pulmonary hydatid disease with fewer complications and a rapid return to work. This technique is easier and safer for right lung and liver dome hydatid cysts.

Concomitant Occurrence of Hepatopulmonary hydatid Cysts in Turkey

Background

We aimed to report the demographic characteristics with diagnosis and treatment methods in patients with concomitant hepatopulmonary hydatid cysts.

Methods

Over a ten-year period (from 2002-2020) in Konya, Turkey, surgery was performed on 52 patients with hepatopulmonary hydatid cyst. Main outcome measure(s) were 52 hydatid cysts patients, which had cysts both in the liver and lungs, were investigated regarding their age, gender, cyst localization, suppuration, symptoms, and treatment methods.

Results

Seventeen of the patients were males. Their mean age was 39.7±18.8 years. The most common occupation was housewifery. The most common symptom was coughing and none of the patients with concomitant hepatopulmonary hydatid cysts was asymptomatic. The pulmonary hydatid cysts were mostly encountered in the right lung and the majority of the hepatic hydatid cysts were observed in the right lobe. The mean hospitalization time of the operated patients was 17.12±6.7 days.

Conclusion

In patients with hydatid cysts localized concomitantly in the right lung and subdiaphragmatic area, right thoracotomy for the pulmonary cyst and a transdiaphragmatic approach for the hepatic cyst is a safe, effective, and comfortable method.

Giant pulmonary hydatid cyst in children

Hydatid disease is still endemic in Tunisia. It is mostly seen in young people less than 40 years and children are affected in one third of cases. The lungs are the predominant location in children. Our study aims to define the particularities of children PHC's (pulmonary hydatic cyst) management, the characteristics of giant cyst and to study predictive factors of complications. We included retrospectively 105 children with PHC followed between 1999 and 2019. Patients were aged less than 16 years with surgically confirmed diagnosis of PHC. Two groups of cysts were defined: giant cysts which were 10 cm across or more, and no giant cysts.The sex-ratio was 1,38 with a mean age of 10.5±3 years. The symptomatology was dominated by cough (59%), thoracic pain (51%) and hemoptysis (46%). Giant cysts were observed in 24 (22.9%) patients. Dyspnea (29% vs 5% p<0.001) and thoracic pain (88% vs .41% p<0.001) were significantly more frequently reported in giant cysts. Eighty-six patients had a single cyst (83%) and 19 had multiple cysts (17%). Giant cysts accounted for 22,9% (24 cases). Thoracic ultrasonography was diagnostic in 77.4%. The thoracic CT scan was performed in 27 children with inaccessible cysts in thoracic ultrasonography or in diagnostic doubt.Patients were all treated surgically. Surgical procedures consisted of cystectomy (59%), pericystectomy (18%) and pulmonary resection when parenchyma was destroyed (23%). Parenchymal resection was more often performed in complicated cysts (27% vs 20% p>0.05) and in giant cysts (41% vs 18% p<0.05). A two-stage thoracotomy was performed in the 4 patients with bilateral cysts. Thirteen patients presented immediate post-operative complications which occurred more frequently in complicated and giant cysts. Hospital stay was longer in complicated cysts (16±9 days vs 7±3 days; p<0.001) and in giant cysts (14±9 days vs 11±8 days; p>0.05). In endemic regions, the diagnosis of PHC in children should be based on the combination of thoracic radiography and ultrasonography which are effective, not costly, safe and accessible. Complicated and giant PHC cause lung damage leading to extensive parenchymal resection. They are more associated with post-operative complications prolonging hospital stay and increasing expenses.

Flexible Fibreoptic Bronchoscopy and Bronchoalveolar Lavage for Confirmation of Pulmonary Hydatid Disease in Children: A Case Series

Hydatid disease of the lungs is common in endemic regions. It can be suspected clinically by non-specific respiratory symptoms in children living in endemic regions, especially when they are close to sheep or dogs. Chest imaging X-ray or computed tomography may show characteristic cysts in some cases, but typical findings are absent in many children. Hydatid serology may contribute to the diagnosis, but does not have sufficient sensitivity for pulmonary cysts. Thus, there is no confirmatory diagnostic test, other than surgical excision and histopathologic examination. Hence, there is a need for more reliable diagnostic tests. We present a series of children, both with and without suspected pulmonary hydatid, wherein flexible fibreoptic bronchoscopy (FFOB) performed under conscious sedation, revealed hydatid membranes in the airways. Bronchoalveolar lavage (BAL) analysis revealed hydatid in most of them. Thus the diagnosis could be confirmed even before surgical excision of cysts was performed. We propose that FFOB with BAL could be useful to confirm the diagnosis of pulmonary hydatid in children. This will be particularly helpful in children without characteristic radiological or serological findings. To the best of our knowledge, this is a completely novel approach to the condition with potential to alter the diagnostic paradigm Lay summary Hydatid disease of the lungs is commonly encountered in endemic regions. However, there is no confirmatory diagnostic test for pulmonary hydatid cyst, other than surgical excision and histopathologic examination. Imaging including chest X-ray and computed tomography may not be typical, especially in complicated cysts and hydatid serology does not have a satisfactory sensitivity for diagnosing lung cysts. Thus, there is a need for more reliable diagnostic tests. We present a series of children, both with and without suspected pulmonary hydatid, wherein flexible fibreoptic bronchoscopy (FFOB) under conscious sedation, revealed hydatid membranes in the airways. Bronchoalveolar lavage (BAL) analysis confirmed hydatid in most of them. We propose FFOB with BAL as a useful diagnostic modality to confirm pulmonary hydatid in children, prior to surgical excision. To the best of our knowledge, this is a completely novel approach to the condition with potential to alter the diagnostic paradigm.

Rare pulmonary tumors and carcinoma mimickers; experience from an interventional radiology unit with radiologic-pathologic correlation-A pictoral essay

BACKGROUND

Although imaging findings along with patients' clinical history may give clue for the etiology of a pulmonary lesion, the differentiation of benign pulmonary lesions from lung cancer could be challenging.

OBJECTIVE

The aim of this review article was to increase the awareness of the carcinoma mimicking lung lesions.

METHODS

This paper was designed to illustrate rare pulmonary tumors and carcinoma mimickers with emphasis on radiologic-pathologic correlation. Pitfalls encountered on CT images and also false positivity of PET-CT scans were also presented.

CONCLUSION

Several benign pulmonary lesions may grow in size on follow-up and some may show pathologic FDG (18F-fluorodeoxyglucose) uptake, which makes them indistinguishable from lung carcinoma by imaging. In addition, some slow-growing malignant lesions, such as carcinoid, may be false-negative on PET/CT scans.

A 27-Year-Old Man With Intermittent Chest Pain During the Last 4 Years

CASE PRESENTATION

A 27-year-old man from Eritrea presented to the ED complaining about a progressively worse blunt chest pain in the anterior right hemithorax. Chest pain started 4 years ago and was intermittent. During the last 6 months, symptoms got worse, and the patient experienced shortness of breath in mild exercise. For this purpose, he visited another institution, where a chest radiograph was performed (Fig 1). He was advised to visit a pulmonologist for further evaluation, with the diagnosis of a loculated pleural effusion in the right upper hemithorax.

Echinococcosis of the spine

Echinococcosis or hydatid disease affecting the spine is an uncommon manifestation of Echinococcus granulosus infection of the spine.More commonly found in endemic areas, it causes significant morbidity and mortality as it grows slowly and produces symptoms mainly by compressing the spinal cord.As diagnostic methods are non-specific, diagnosis and management are usually delayed until the disease is advanced, thereby therapy is usually unlikely.Treatment is usually surgical, aiming at cyst excision, spinal cord decompression and spinal stabilization.This article summarizes the clinical findings of echinococcosis of the spine, discusses the specific laboratory and diagnostic findings, lists the current treatment options, and reviews the patients' outcomes.The aim is to prompt clinicians to be aware of the possibility of echinococcosis as a possible diagnosis in endemic areas. Cite this article: EFORT Open Rev 2021;6:288-296. DOI: 10.1302/2058-5241.6.200130.

The spectrum of imaging findings in pulmonary hydatid disease and the additive value of T2-weighted magnetic resonance imaging in its diagnosis

Purpose

To describe the spectrum of imaging findings in pulmonary echinococcosis and to study the additive value of T2-weighted magnetic resonance imaging (MRI) in the characterisation of pulmonary hydatid disease.

Material and methods

This was a descriptive, prospective study conducted for a period of 3 years from December 2016 to November 2019. Patients suspected of having pulmonary echinococcosis (n = 110) on preliminary chest radiography were examined with chest computed tomography (CT). Among them 41 cases were additionally examined with T2-weighted MRI of thorax. Final diagnosis was based on surgery or histopathology.

Results

Of the 110 patients enrolled for the study 15 were lost to attrition, and among the final cohort of 95 patients CT correctly diagnosed 68/84 (80.9%) as hydatid cyst, whereas 16/84 (19.1%) received an erroneous alternate diagnosis on CT. Based on the classical findings of hyperintense pulmonary cystic lesion with T2-weighted hypointense rim or detached internal T2-weighted hypointense membrane, a correct diagnosis of hydatid cyst was possible in 30 patients whereas a correct alternate diagnosis was made in 8 cases. T2-weighted MRI was found to have sensitivity of 96.7%, specificity of 80%, positive predictive value (PPV) of 93.7% and negative predictive value (NPV) of 88.9% with an overall diagnostic accuracy of 92.6%. Using the McNemar test, MRI was found to be diagnostically superior to CT (p = 0.019).

Conclusions

Most of the pulmonary hydatid cysts can be diagnosed on CT; however, sometimes the findings may be indeterminate or atypical, leading to a diagnostic dilemma. MRI, owing to its ability to demonstrate hypointense endocyst, can act as a useful adjunct to correctly diagnose hydatid cyst or suggest an alternative diagnosis.

Inflammatory Lesions Mimicking Chest Malignancy: CT, Bronchoscopy, EBUS, and PET Evaluation From an Oncology Referral Center

Infective and inflammatory diseases can mimic malignancy of the lung. Granulomatous inflammations are common causes of pulmonary nodule, mass, or nodal disease. Systemic infection or inflammation also commonly involves the lung that may raise suspicion of a malignant process. Even in patients with a known malignancy, inflammatory diseases can simulate new metastasis or disease progression. Knowledge of the imaging features of these diseases is essential to prevent missed or overdiagnosis of malignancy. Radiologists also need to be familiar with the scope and limitations of bronchoscopy, endobronchial ultrasound, PET-CT, and biopsy to guide clinical management. In this review, we discuss the imaging features and diagnostic approach of common mimickers of chest malignancy that involve the chest wall, pleura, lung parenchyma, and mediastinal nodes.

Radiological manifestations of thoracic hydatid cysts: pulmonary and extrapulmonary findings

Hydatid cyst caused by the larval form of Echinococcus is a worldwide zoonosis. The lungs and liver are the most common sites involved. While the lung parenchyma is the most common site within the thorax, it may develop in any extrapulmonary region including the pleural cavity, fissures, mediastinum, heart, vascular structures, chest wall, and diaphragm. Imaging plays a pivotal role not only in the diagnosis of hydatid cyst, but also in the visualization of the extent of involvement and complications. The aim of this pictorial review was to comprehensively describe the imaging findings of thoracic hydatid cyst including pulmonary and very unusual extrapulmonary involvements. An outline is also given for the findings of complications and differential diagnosis of thoracic hydatid cyst.

Giant isolated hydatid lung cyst: two case reports

BACKGROUND

Echinococcosis is a parasitic disease caused by Echinococcus granulosus and causes cystic lesions in the liver and lungs commonly. It is endemic in many parts of the world, and though humans are incidental hosts of the parasite, the disease can have severe consequences.

CASE PRESENTATION

We present two patients from pastoralist (Maasai) communities in rural Tanzania with long-standing chest pain accompanied by hemoptysis. Both were managed surgically after diagnosis, but one patient died of the complications following rapture of the cyst during surgery. Histopathological evaluation of the specimens confirmed the diagnosis of giant hydatid cysts.

CONCLUSION

Animal-keeping communities such as the Maasai are at risk of echinococcosis because of their close proximity to animals. The diagnosis can be made on the basis of history and radiological as well as laboratory findings. Surgery is a recommended mode of treatment, though it carries a high risk, especially when the cyst ruptures. Primary preventive measures are thus necessary in order to avoid the secondary and tertiary complications of the management of giant hydatid cysts, which is difficult in resource-limited endemic areas.

Surgical management of pulmonary hydatid cysts in children in KwaZulu-Natal Province, South Africa

Background

Pulmonary hydatid cyst disease is still a major problem in countries like South Africa (SA), where livestock farming is common. Hydatidosis has a variable clinical course depending on the size, location and complications of the cyst. For pulmonary cysts of any size, surgery remains the gold standard for treatment, with lung conservation surgery being the ideal.

Objectives

To describe the epidemiology, clinical presentation, surgical management, and surgical outcomes of paediatric pulmonary hydatid disease in children referred to the Department of Cardiothoracic Surgery at Inkosi Albert Luthuli Central Hospital (IALCH) in KwaZulu-Natal Province, SA.

Methods

We retrospectively reviewed and analysed the medical records of 38 children between the ages of 0 and 18 years with pulmonary hydatid cysts, who were referred to the Department of Cardiothoracic Surgery at IALCH and underwent surgical management between 1 January 2008 and 31 December 2018. The medical records were evaluated for patients’ demographics, clinical evaluation, surgical management strategies and surgical outcomes.

Results

Of the 38 patients, 60.5% were male, with a mean age of 6.5 years. More than two-thirds of the patients (68.4%) were from the Eastern Cape and 31.6% were from KwaZulu-Natal. The majority of the cysts (84.2%; n=32) were classified as large (5 - 9 cm in diameter) and giant (≥10 cm in diameter). Forty-eight surgical procedures were performed and lung preservation surgery by enucleation and capitonnage was preferred. Some patients developed postoperative complications such as prolonged air leaks from bronchopleural fistula (18.8%; n=9) and 88.9% (n=8) of these patients healed with chest tube drainage and physiotherapy. Lung resection was only required in 4% (n=2) of the patients. The mean (standard deviation) number of days spent in hospital was 7 (4) days. All children survived with no recurrences.

Conclusion

Conservative surgical procedures such as enucleation of the cysts of any size are possible, safe, reliable and reproducible.

Intrapulmonary mature cystic teratoma of the lung: case report of a rare entity

Background

Intrapulmonary teratoma (IPT) is a rare type of extra gonadal teratoma which often presents with non-specific symptoms and can be misdiagnosed as other diseases. Here we report a patient with IPT which was initially misdiagnosed as lung hydatid cyst versus abscess.

Case presentation

We report an intrapulmonary teratoma in a 27-year-old female presenting with persistent chest pain and dyspnea since a few years prior to her admission with associated symptoms of cough and fever. Chest x-ray only showed left side massive pleural effusion and computed tomography scan of the lungs was suggestive of hydatid cyst or a lung abscess. She underwent lobectomy and postoperative histopathological study revealed IPT as the final diagnosis.

Conclusion

Due to the non-specific symptoms and rarity, IPT can be easily misdiagnosed at first. It is essential that physicians take into account the possibility of IPT when approaching a new case of lung mass.

Myocardial Echinococcosis: Rare Manifestation of a Common Parasitic Disease in Northern Tanzania

Hydatid (Echinococcal) disease often involves the liver and lungs but in sporadic cases, it can involve cardiac structures. A 24-year-old male was referred with symptoms of cough and shortness of breath and a provisional diagnosis of metastatic disease of unknown primary to the lung, which was based on a chest X-ray (CXR). Incidentally, on echocardiogram, he was found to have right ventricular (RV) and myocardial multiseptated cysts, which were compatible with cardiac echinococcosis, as the patient had multiple bilateral lung cysts as well. Imaging with ultrasound, computed tomography (CT) scan, and magnetic resonance imaging (MRI) has ameliorated the diagnosis of hydatid disease location in various body parts. However, for earlier and accurate diagnosis, a high index of suspicion is required in endemic areas, especially in vulnerable populations such as pastoralists.

The clinical and cytomorphological spectrum of hydatid disease

INTRODUCTION

Hydatid disease (HD) is caused by the tapeworm of the genus Echinococcus. Fine-needle aspiration cytology (FNAC) is an expedient diagnostic technique that may be used for its rapid diagnosis.

AIM

To study the clinical and cytomorphological spectrum of HD diagnosed by cytology.

MATERIAL AND METHODS

A total of 24 patients diagnosed with HD on FNAC and fluid were studied over a period of 5.5 years. May Grunwald Giemsa, Periodic acid Schiff, and Haematoxylin and Eosin stained smears were studied and analysed for the cytomorphological spectrum of HD.

RESULTS

Amongst the 24 patients studied, the mean age was 29.8 years (range 6-64 years). There was equal sex preponderance with 12 males and 12 females. The most common organ involved was lung (54.1% of cases) followed by liver (25% of cases). Presence of laminated membranes (n-20, 83.3%) followed by presence of hooklets (n-13, 54.1%) were the common cytological features. Scolices and protoscolices representing endocyst were seen in 37.5% of cases (n-9).

CONCLUSION

Clinicians and pathologists should be aware of the clinical and morphological spectrum of HD respectively for immediate diagnosis followed by prompt management.

Chest imaging using signs, symbols, and naturalistic images: a practical guide for radiologists and non-radiologists

Several imaging findings of thoracic diseases have been referred-on chest radiographs or CT scans-to signs, symbols, or naturalistic images. Most of these imaging findings include the air bronchogram sign, the air crescent sign, the arcade-like sign, the atoll sign, the cheerios sign, the crazy paving appearance, the comet-tail sign, the darkus bronchus sign, the doughnut sign, the pattern of eggshell calcifications, the feeding vessel sign, the finger-in-gloove sign, the galaxy sign, the ginkgo leaf sign, the Golden-S sign, the halo sign, the headcheese sign, the honeycombing appearance, the interface sign, the knuckle sign, the monod sign, the mosaic attenuation, the Oreo-cookie sign, the polo-mint sign, the presence of popcorn calcifications, the positive bronchus sign, the railway track appearance, the scimitar sign, the signet ring sign, the snowstorm sign, the sunburst sign, the tree-in-bud distribution, and the tram truck line appearance. These associations are very helpful for radiologists and non-radiologists and increase learning and assimilation of concepts.Therefore, the aim of this pictorial review is to highlight the main thoracic imaging findings that may be associated with signs, symbols, or naturalistic images: an "iconographic" glossary of terms used for thoracic imaging is reproduced-placing side by side radiological features and naturalistic figures, symbols, and schematic drawings.

Computer Tomography (CT) Characteristics of Pulmonary Cystic Echinococcosis

INTRODUCTION

Cystic echinococcosis (CE) is a common zoonosis worldwide. The two most frequent location of CE are liver and lung. Confirmatory diagnosis of CE is routinely performed sung imaging methods such as computer aided tomography and nuclear magnetic resonance in humans.

AIM

to investigate CT scan imaging of patients with pulmonary CE in Masih Daneshvari Hospital from 2011 to 2017.

MATARIAL AND METHODS

This descriptive-analytic study was carried out on patients with pulmonary CE referring to Masih Daneshvari Hospital. By using the convenience sampling, 195 cases were selected from eligible patients. The data collection tool was a researcher-made questionnaire that included demographic, clinical and laboratory information. Data were analyzed using SPSS software version 20.

RESULTS

In this study, 84.1% and 15.9% of patients were diagnosed using surgical method and CT scan, respectively. Our findings indicated CE was most commonly located in liver (28.2%) and spleen was considered as the lowest location (3.1%). Furthermore, cough was the most common clinical symptom of patients. The lower right lobe opacity was found to be higher, while and Lingula was the least frequent.

CONCLUSION

According to the findings of this study, surgery is the most important diagnostic and cough method as the most common clinical symptom of the disease. Since the CE with atypical symptoms is relatively common, physicians should always consider the lung CE in differential diagnosis of localized radiological images.