Abstract Introduction. Paradoxical embolism is a thrombotic event originating in the venous circulation, which manifests as arterial embolism through an anatomical cardiac or pulmonary defect. It is mainly associated with stroke, also presenting as acute myocardial infarction, renal infarction, and other ischemic events. Clinical case. A 47-year-old patient was admitted due to abdominal pain, which required emergency surgical management, finding significant intestinal ischemia. Additional studies found protein S deficiency and evidence of a patent foramen ovale. Discussion. Arterial thrombosis is known as unusual thrombosis; this situation requires to rule out associated thrombophilia or other prothrombotic diseases. Protein S deficiency is a rare thrombophilia, which in adults causes venous thrombosis. In the presence of anatomical defects, such as a patent foramen ovale, it can progress to arterial embolism, presenting a picture of paradoxical embolism. The study work of these patients requires imaging that demonstrates the aforementioned defect, as well as the possible origin of the emboli. Management is based on full anticoagulation, treatment of existing thrombotic manifestations, and management of the anatomical defect. Conclusions. Paradoxical embolism should be suspected in case of unusual thrombosis. It requires exhaustive studies based on imaging, and management should consist of anticoagulation and closure of the defect.

Resumen Introducción. La embolia paradójica es un evento trombótico originado en la circulación venosa, que se manifiesta como embolismo arterial por medio de un defecto anatómico a nivel cardíaco o pulmonar. Se asocia principalmente a eventos cerebrovasculares, aunque se han encontrado casos de infarto agudo de miocardio, infarto renal y otros eventos isquémicos. Caso clínico. Paciente de 47 años, quien consultó por cuadro de dolor abdominal, que requirió manejo quirúrgico de urgencia, donde identificaron isquemia intestinal importante. Los estudios adicionales hallaron déficit de proteína S y persistencia de foramen oval permeable. Resultados. La presencia de trombosis arterial se conoce como trombosis de sitios inusuales y requiere de estudios para descartar trombofilias asociadas u otros estados protrombóticos. El déficit de proteína S es una trombofilia infrecuente, la cual se asocia en la vida adulta a eventos trombóticos de origen venoso. En presencia de defectos anatómicos, como un foramen oval permeable, puede progresar a embolia arterial, configurando un cuadro de embolismo paradójico. La estratificación de estos pacientes requiere imágenes que demuestran el defecto mencionado, así como el posible origen de los émbolos. El manejo se basa en anticoagulación plena, manejo de soporte, resolver las manifestaciones trombóticas existentes y un cierre temprano del defecto anatómico. Conclusiones. El embolismo paradójico debe sospecharse en caso de trombosis de sitios inusuales. Requiere de un estudio exhaustivo con imágenes y su manejo debe basarse en anticoagulación y cierre del defecto.

ABSTRACT: Tumor embolization is a well-described cause of unexpected death in human oncologic patients; however, it is poorly explored in veterinary medicine. We report a case of pulmonary tumor embolization in a dog with sudden death. During necropsy, a neoplastic mass was observed replacing the left adrenal gland and forming an intravascular thrombus within the central adrenal vein. A large embolus occluded the left pulmonary artery. The adrenal mass was histologically confirmed as a pheochromocytoma, and the embolus was constituted of neoplastic cells. Multiple smaller neoplastic emboli were observed within the pulmonary artery branches. Tumor embolization should be considered as a possible cause of sudden death in dogs, particularly in oncologic patients. ABSTRACT welldescribed well described patients however medicine necropsy vein pheochromocytoma cells branches dogs

RESUMO: Embolismo tumoral é uma causa bem descrita de morte súbita em pacientes oncológicos humanos, entretanto, é pobremente explorado em medicina veterinária. Descreve-se um caso de embolização pulmonar neoplásica em um cão com morte súbita. Na necropsia, uma massa neoplásica foi observada substituindo a adrenal esquerda e formando um trombo intravascular na veia central da adrenal. Um êmbolo foi observado ocluindo a artéria pulmonar esquerda. A massa da adrenal foi histologicamente confirmada como um feocromocitoma, e o êmbolo era constituído de células neoplásicas. Múltiplos êmbolos neoplásicos menores foram observados histologicamente nas ramificações da artéria pulmonar. O Embolismo tumoral deve ser considerado como possível causa de morte súbita em cães, particularmente em pacientes oncológicos. RESUMO humanos entretanto veterinária Descrevese Descreve se necropsia feocromocitoma neoplásicas cães

Abstract Introduction: Primary pleomorphic pulmonary angiosarcomas are extremely rare tumors which could be easily mistaken for pulmonary emboli. Background and findings: We describe the successful perioperative management of a patient with a pulmonary arterial mass which turned out to be a primary pulmonary angiosarcoma. The severe pulmonary hypertension was a particular challenge compounded with the site and adhesions of the tumor, and pulmonary hemorrhage. The procedure was successfully performed with strict hemodynamic control ensuring stable systemic and pulmonary arterial pressures using perioperative transesophageal echocardiography to continuously monitor cardiac function, along with other standard cardiac surgical monitors including depth of anesthesia monitoring. Conclusion: Tight hemodynamic control, ensuring stable pulmonary arterial pressures using perioperative echocardiography, and thorough preparation with measures to reduce and prevent increase in pulmonary arterial pressure along with close communication within the multidisciplinary team are essential for successful management of patients with this pathology. Introduction emboli findings angiosarcoma tumor hemorrhage function monitoring Conclusion pathology

ABSTRACT Pulmonary arteriovenous malformations (PAVMs) are abnormal vascular connections between pulmonary arteries and veins, often associated with hereditary hemorrhagic telangiectasia (HHT). Most PAVMs are asymptomatic, but life-threatening complications like pulmonary hemorrhage, brain abscesses, and paradoxical emboli can emerge, so prompt diagnosis and treatment are crucial. We report a case of sudden pediatric death in a two-year-old female with no past medical history. Initial vomiting and fast deterioration resulted in a sudden cardiac arrest. The postmortem examination found histological evidence of consistent, extensive lung damage. The absence of the characteristic symptoms made for some challenges when it came to diagnosis, showing precisely that in early life, you could well have many difficulties in catching PAVMs. This case highlights the need to take PAVMs into account as a potential cause of sudden death, particularly when there are no conspicuous symptoms. Awareness among forensic pathologists and consideration of genetic analysis for HHT in such cases is crucial for accurate diagnosis and management. (PAVMs veins HHT. . (HHT) asymptomatic lifethreatening life threatening hemorrhage abscesses emerge twoyearold two year old history arrest consistent damage management (HHT

ABSTRACT Candida endocarditis is a very serious manifestation of candida infections, and it has increased in incidence over the past years. Of these, C. parapsilosis has been described as a cause of endocarditis in native valves of intravenous drug users and prosthetic valves. We report the case of a female that developed a cerebrovascular accident secondary to emboli from aortic prosthetic valve C. parapsilosis endocarditis, despite apparently normal echocardiography. She received antifungal therapy without surgical intervention.

RESUMEN La endocarditis por Candida spp. es una manifestación muy grave de las infecciones por este patógeno y su incidencia ha ido aumentando en los últimos años. La Candida parapsilosis se ha descrito como causa de endocarditis en válvulas nativas de usuarios de drogas intravenosas y prótesis valvulares. Presentamos el caso de una mujer que desarrolló un accidente cerebrovascular secundario a émbolos fúngicos procedentes de una prótesis valvular aórtica infectada por C. parapsilosis, a pesar de un ecocardiograma sin vegetaciones. La paciente recibió tratamiento antifúngico sin necesidad de intervención quirúrgica.

Abstract Introduction: acute arterial ischemia is recognized as a life-threatening clinical syndrome related to thrombosis or systemic embolism. The aorta is the source of 5 % of all embolism cases, usually related to atherosclerotic risk factors. Currently, no unified guidelines establish this entity's optimal treatment. Case presentation: a 70-year-old male with a smoking history presents to the emergency department complaining of pain, paresthesias, pallor, and coldness in the lower limbs for two months. Acute arterial ischemia is reported, anticoagulation initiated, and thrombolysis of popliteal vessels performed. Subsequently, multiple embolic events develop, and an ulcerated aortic plaque with a large mobile thrombus is reported; hybrid therapy is considered. However, new emboli develop, and the patient dies. Conclusions: recognizing the aorta as a potential source of embolism is essential. A judicious diagnostic approach should be performed, and an adequate indication for anticoagulation and appropriate surgical intervention should be established.

Resumen Introducción: la isquemia arterial aguda se reconoce como un síndrome clínico potencialmente mortal relacionado con trombosis o embolia sistémica. La aorta es la fuente del 5 % de todos los casos de embolia y suele relacionarse con factores de riesgo ateroescleróticos. Actualmente no existen guías unificadas que establezcan el tratamiento óptimo de esta entidad. Presentación del caso: masculino de 70 años, con antecedente de tabaquismo, acude al servicio de urgencias por 2 meses de dolor en miembros inferiores, parestesias, palidez, frialdad. Se documenta una isquemia arterial aguda, se inicia anticoagulación y se lleva a trombólisis de vasos poplíteos, posteriormente presenta múltiples eventos embólicos, se documenta la presencia de una placa ulcerada en aorta con un gran trombo móvil, se platea terapia híbrida (endovascular y cirugía abierta), sin embargo, desarrolla nuevas embolias y muere. Conclusiones: la aorta debe considerarse como fuente embólica, debe realizarse un enfoque diagnóstico juicioso y establecer una adecuada indicación de anticoagulación e intervención quirúrgica apropiada.

Resumen El síndrome de Lemierre, también denominado trom boflebitis séptica de la vena yugular interna, necrobaci losis o sepsis postanginal es una infección que inicia en el espacio orofaríngeo, se complica con tromboflebitis séptica de la vena yugular interna y metástasis infeccio sas. La rápida progresión a cuadros clínicos graves que comprometen la vida del paciente y su baja frecuencia justifican la divulgación de casos clínicos. Se presenta el caso de una mujer de 27 años de edad, que a las 48 horas de completar el tratamiento con fenoximetilpenicilina por una infección odontógena evolucionó con edema facial y trismus. En la angio-TC de macizo craneofacial se evidenció extenso trombo en la vena yugular interna y en la tomografía computarizada de tórax, embolias sépticas pulmonares. El tratamiento consistió en antibió ticos endovenosos de amplio espectro y anticoagulación de manera precoz.

Abstract Lemierre’s syndrome, also called septic thrombo phlebitis of the internal jugular vein, necrobacillosis or postanginal sepsis, is an infection that begins in the oropharyngeal space, is complicated by septic throm bophlebitis of the internal jugular vein and infectious metastases. The rapid progression to serious clinical conditions that compromise the patient’s life and its low frequency justify the disclosure of clinical cases. We present the case of a 27-year-old woman who de veloped facial edema and trismus 48 hours after com pleting treatment with phenoxymethylpenicillin for an odontogenic infection. An angio-CT of the craniofacial massif revealed an extensive thrombus in the internal jugular vein and a computed tomography of the chest showed septic pulmonary emboli. Treatment consisted of broad-spectrum intravenous antibiotics and early anticoagulation.

Abstract Introduction: Mycotic or primary infected aortic aneurysms comprise aproximately 1.3% of all aortic aneurysms and may be caused by septic emboli to the vasa vasorum, by haematogenous spread during bacteraemia or by direct extension of an adjacent infection leading to an infectious degeneration of the arterial wall and aneurysm formation. The objective of this report is to describe a clinical case of a complicated mycotic aortic aneurysm. Case report: A male, 69-year-old patient, with medical background of diabetes, hypertension and a bladder carcinoma (surgically ressected 5 years before, complicated at the time with an E.coli septicaemia), presented at the ER with generalised malaise, asthenia, anorexia, abdominal pain, diarrhea and fever, with 1 week of evolution. At admission, clinical examination revealed poor general condition, fever (39ºC), noral blood pressure, and the abdominal examination showed no abnormalities. Laboratory results revealed an stable haemoglobin of 13 g/dL, leukocytosis (19850/UI) and neutrophilia (90%), an a C Reactive Protein of 350mg/dl. A Computed Tomography Angiography (CTA) revealed a 3,5 cm saccular juxtarenal AAA, with peri and intra-aortic gas, strongly suggestive of an mycotic AAA (MAA). Hospitalization was indicated and a septic and immunologic screening was perfomed. The patient started a broad-spectrum antibiotic with meropenem and vancomycin and clinical, laboratory and hemodynamic surveillance. Blood and urine cultures revealed a E.Coli infection, and directed antibiotic was started. After 10 days os hospitalization, the patient was haemodinamic stable, presented no fever or abdominal pain, however inflammatory parameters remained elevated, and a new CTA that showed a daunting increase of 4 cm of the AAA (7,5 cm) with signs of contained ruture. An emergency intervention was decided and the patient underwent an thoracophrenolaparotomy and aorto-aortic interposition with bovine pericardium patch. After 24h of surgery the patient died of septic shock. Conclusion: MAA is a rare and threatening disease with rapid progression and high mortality. Even with broad-spectrum antibiotic and rapid surgical response, the tragic outcome is often the unavoidable result

ABSTRACT Introduction: 80% of strokes result in ischemic type and at least 20-30% are caused by stenosis of the extracranial carotid artery. Carotid endarterectomy has as its main objective to remove atheromatous plaques, which are sources of emboli for the brain, and improve blood flow to this organ. Objective: To characterize the morbidity of carotid endarterectomy at the "Enrique Cabrera" General Teaching Hospital from 2018 to 2021. Methods: A descriptive, cross-sectional study was conducted in 32 patients, who underwent carotid endarterectomy. Data collection was carried out by reviewing medical records. The study period spanned from January 2018 to January 2021. Results: The male sex predominated (65.6 %) and the mean age was 68.8 years. The most frequent risk factors were high blood pressure and smoking with 75% and 65.6%, respectively. Cerebrovascular disease with minimal sequelae was the most frequent clinical form in 40.6% of cases. A statistically significant association was found between diabetes mellitus and clinical forms, and between peripheral arterial disease and the occurrence of complications. The left carotid was the most affected with 53% and the percentage of stenosis, between 70% and 99%, was found in 55.9% of patients. The following complications were the most common: cranial nerve injury (5.8%) and cervical hematoma (5.8%). Eversion endarterectomy was performed in 97% of cases. Conclusions: The safety and success of carotid endarterectomy were demonstrated. Most of the patients had a satisfactory evolution, and there were few complications and zero mortality.

RESUMEN Introducción: El 80 % de los accidentes cerebrovasculares resulta de tipo isquémico y al menos el 20-30 % está provocado por estenosis de la arteria carótida extracraneal. La endarterectomía carotídea tiene como principal objetivo eliminar las placas de ateroma, que son fuentes de émbolos para el encéfalo, y mejorar el flujo sanguíneo a este órgano. Objetivo: Caracterizar la morbilidad de la endarterectomía carotídea en el Hospital General Docente “Enrique Cabrera” desde 2018 hasta 2021. Métodos: Se realizó un estudio de tipo descriptivo y corte transversal a 32 pacientes, a los cuales se les realizó endarterectomía carotídea. La recolección de los datos se efectuó mediante la revisión de historias clínicas. El período de estudio abarcó desde enero de 2018 hasta enero de 2021. Resultados: Predominó el sexo masculino (65,6 %) y la media de edad fue de 68,8 años. Los factores de riesgo más frecuentes resultaron la hipertensión arterial y el tabaquismo con 75 % y 65,6 %, respectivamente. La enfermedad cerebrovascular con secuela mínima constituyó la forma clínica más frecuente en el 40,6 % de los casos. Se encontró asociación estadísticamente significativa entre diabetes mellitus y formas clínicas, y entre enfermedad arterial periférica y la aparición de complicaciones. La carótida izquierda resultó la más afectada con 53 % y el porcentaje de estenosis, entre 70 % y 99 %, se encontró en el 55,9 % de los pacientes. Con mayor frecuencia se presentaron las complicaciones: lesión de nervios craneales (5,8 %) y hematoma cervical (5,8 %). La endarterectomía por eversión se realizó en el 97 % de los casos. Conclusiones: Se demostró la seguridad y el éxito de la endarterectomía carotídea. La mayoría de los pacientes tuvo una evolución satisfactoria, y se presentaron escasas complicaciones y mortalidad nula.

Abstract This report describes the handling and clinical evolution of a malignant feline mammary carcinoma (FMC) in an eight-year-old female crossbred cat with a congenital disorder. Hence, the efficacy of tumor mass removal and the case prognosis was established by postoperative routine histological examination. A 6 cm diameter lump in the left thoracic mammary gland of multinodular appearance and purulent exudate with a reddish hue was excised after the entire mastectomy. The histopathological analysis showed the presence of numerous lymphovascular tumor emboli and frequently mitotic cells with hyperchromatic nuclei. These were consistent with an aggressive malignancy with a poor prognosis explaining the patient's death within 7 weeks after surgery. Histology and cytology findings are of critical importance to clinicians in the management of the most common mammary malignancies in cats, to provide the best possible relief to animals with life-threatening cancer. It could also serve as a cancer model for advancing knowledge in congenitally affected humans.

Resumen En esta publicación se describe el manejo y la evolución clínica de un carcinoma mamario felino (CMF) maligno en una gata mestiza de ocho años de edad con un trastorno congénito. La eficacia de la extirpación de la masa tumoral y el pronóstico del caso se establecieron mediante el examen histológico de rutina postoperatorio. Tras una mastectomía completa se extirpó un bulto de 6 cm de diámetro en la glándula mamaria torácica izquierda de aspecto multinodular y exudado purulento de coloración rojiza. El análisis histopatológico mostró la presencia de numerosos émbolos tumorales linfovasculares y células con alta frecuencia de figuras mitóticas con núcleos hipercromáticos. Estos hallazgos fueron consistentes con una neoplasia agresiva de mal pronóstico, lo que explicaba el fallecimiento de la paciente a las 7 semanas de la cirugía. Los hallazgos histológicos y citológicos son de importancia crítica para los clínicos en el manejo de las neoplasias mamarias más comunes en los gatos, con el fin de aliviar de la mejor manera posible a los animales con cánceres que amenazan su vida. También podría servir como modelo de cáncer para avanzar en el conocimiento de patologías similares en otras especies.

BACKGROUND: A high incidence of thromboembolic phenomena has been widely reported in patients with coronavirus disease 2019 (COVID-19) pneumonia. There is, however, a paucity of data detailing the incidence and characteristics of pulmonary emboli (PE) in COVID-19 patients in the South African setting OBJECTIVES: To describe the incidence and characteristics of PE confirmed by CT pulmonary angiogram (CTPA) in patients with COVID-19 pneumonia admitted to a tertiary hospital in the Western Cape, South Africa METHODS: This was a retrospective-, descriptive study of all adult patients with COVID-19 pneumonia confirmed by polymerase chain reaction (PCR) undergoing CTPA for suspected PE while admitted to Groote Schuur Hospital. The study period was from 01 April 2020 to 30 September 2020 RESULTS: The study cohort consisted of 116 patients, 59% being female, of whom 29% were pregnant or in the postpartum period. The median age for both genders combined was 49.5 years. The overall incidence of PE was 19%, with 20% in our subset of pregnant and postpartum patients. The majority (64%) of PE's were reported as being segmental in anatomical location CONCLUSION: The noteworthy cohort included patients with pulmonary tuberculosis (PTB), HIV as well as pregnant and postpartum patients. The overall incidence of PE was 19% with no significant differences in demographics, comorbidities or D-dimer levels between patients with or without PE. The importance of a high clinical index of suspicion together with the role of CTPA in diagnosing PE in hospitalised COVID-19 patients is emphasised

Abstract: Cardiac tumors may be primary or, more frequently secondary or associated to metastasis. Atril myxoma es the most frequent primary tumor, usually located in the left atrium. Clinical manifestations include those due to mitral valve occlusión, emboli and general non spedific symptoms and signs. Herein we report the clinical case of a 32 year old patient with severe pulmonary hypertension and bilateral pulmonary embolism. The tumor was extirpated, and he received phosphoro-diesterase inhiborts and anticoagulants. Subsequent clinical course was satisfactory. A brief discussion of this condicion is included.

Resumen: Los tumores cardíacos pueden ser primarios o, más frecuentemente secundarios o metastásicos. Entre los tumores primarios es más frecuente el mixoma, cuya ubicación más común es en la aurícula izquierda. Las manifestaciones clínicas son diversas, producidas principalmente por obstrucción mecánica, embolizaciones, y manifestaciones constitucionales. Se comunica el caso de un paciente de 32 años, con cuadro clínico de insuficiencia cardíaca, hipertensión pulmonar severa y tromboembolismo pulmonar bilateral. Se hizo el diagnóstico de mixoma auricular izquierdo. Se resecó el tumor y se manejó la hipertensión pulmonar desde el ingreso al hospital con inhibidores de la fosfodiesterasa asociado a anticoagulación. Se discute el tema dando énfasis a aspectos fisiopatológicos involucrados tanto en la hipertensión pulmonar como en la presencia de tromboembolia pulmonar.

Resumo A infecção pelo coronavírus 2 causador da síndrome respiratória aguda grave (SARS-CoV-2) em humanos foi detectada pela primeira vez em Wuhan, na China, em 2019 e dispersada mundialmente ao longo de 2020. As diferentes manifestações clínicas, com amplo espectro de apresentação, desde infecções assintomáticas até formas graves que podem levar a óbito, são desafiadoras. Este trabalho objetiva descrever uma série de quatro casos de isquemia arterial aguda dos membros superiores em pacientes diagnosticados com COVID-19, os quais foram manejados clinicamente com anticoagulação, antiagregação plaquetária e uso de prostanoides. Dois pacientes receberam alta hospitalar com regressão e delimitação da área isquêmica, sem necessidade de intervenção cirúrgica, e dois pacientes faleceram em decorrência de complicações pulmonares. Uma adequada compreensão da fisiopatologia dessa doença pode favorecer um melhor manejo clínico de suas complicações.

Abstract Infection by coronavirus 2, cause of the severe acute respiratory syndrome (SARS-CoV-2) in humans, was detected for the first time in Wuhan, China, in 2019, and spread globally over the course of 2020. Its different clinical manifestations are challenging, with a wide spectrum of presentations, ranging from asymptomatic infections to severe forms that can result in death. The objective of this study is to describe a series of four cases of acute arterial ischemia involving the upper limbs in patients diagnosed with COVID-19, which were managed clinically with anticoagulation, platelet antiaggregation, and prostanoids. Two patients were discharged from hospital with regression and delimitation of the ischemic zone, without needing surgical intervention, while two patients died from pulmonary complications. Adequate understanding of the pathophysiology of this disease could support better clinical management of its complications.

Resumo Objetivo Este estudo avaliou o risco da síndrome hereditária de câncer de mama e ovário (HBOC, na sigla em inglês) em pacientes com câncer de mama utilizando a ferramenta Familial History Screening 7 (FHS-7), um questionário validado de baixo custo e com alta sensibilidade capaz de rastrear o risco de HBOC na população. Métodos Mulheres diagnosticadas com câncer de mama (n=101) assistidas pelo Sistema Único de Saúde da 8ª Regional de Saúde do estado do Paraná responderam ao questionário FHS-7, e os resultados foram analisados pelo software IBM SPSS for Windows, Version 25.0. (IBM Corp., Armonk, NY, EUA). Resultados A ocorrência do risco de HBOC foi de 19,80% (n=20). Pacientes em risco exibiram características agressivas do tumor como tumores de alto grau (30%), presença de êmbolos angiolinfáticos (35%) e pré-menopausa ao diagnóstico (50%). Associações significantes foram observadas entre a prevalência de tumores de alto grau e diagnóstico abaixo de 50 anos no grupo HBOC (p=0.003). Conclusão Nossos achados sugerem uma possível herança familiar associada a piores características clínicas em mulheres com câncer de mama nessa população, indicando que a investigação de HBOC pode ser realizada, inicialmente, com instrumentos de baixo custo, como o FHS-7.

Abstract Objective This study evaluated the risk of the hereditary breast and ovarian cancer (HBOC) syndrome in patients with breast cancer by using the Family History Screening 7 (FHS-7) tool, a validated low-cost questionnaire with high sensitivity able to screen the HBOC risk in the population. Methods Women diagnosed with breast cancer (n=101) assisted by the Unified Health System at the 8th Regional Health Municipal Office of the state of Paraná answered the FHS-7, and the results were analyzed using IBM SPSS Statistics for Windows, Version 25.0. software (IBM Corp., Armonk, NY, USA). Results The risk of HBOC was 19.80% (n=20). Patients at risk exhibited aggressive tumor characteristics, such as high-grade tumors (30%), presence of angiolymphatic emboli (35%), and premenopausal at diagnosis (50%). Significant associations between the prevalence of high-grade tumors were observed inwomen younger than 50 years at diagnosis with HBOC (p=0.003). Conclusion Our findings suggest a possible family inheritance associated with worse clinical features in women with breast cancer in this population, indicating that HBOC investigation can be initially performed with low-cost instruments such as FHS-7.