Orbital doppler ultrasound as an ancillary test for diagnosing brain death: A prospective, single blind comparative study.

OBJECTIVE: Transcranial Doppler ultrasound (TDUS), computed tomography angiography (CTA), and transcranial Doppler ultrasound to detect cerebral blood flow are among the adjunctive tests in diagnosing brain death. This study aimed to investigate the effectiveness of orbital doppler ultrasound (ODUS). METHODS: This prospective, single-blind study included 66 patients for whom brain death was to be diagnosed. Primary outcome measures were ODUS measurements, Ophthalmic artery peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistive indices (RI) measurements recorded during the brain death determination process. Secondary outcome measures were computed tomography angio (CTA), transcranial Doppler ultrasound (TDUS), and demographic data. RESULTS: This study investigating the effectiveness of ODUS in diagnosing brain death provided diagnostic success with 100% sensitivity and 93% specificity compared to CT angiography. It was noted that anatomical variations may limit its use. CONCLUSION: ODUS was found to have high sensitivity and specificity in the diagnosis of clinical brain death. It may assist in early prognostic assessment and shorten patient follow-up and diagnostic processes.

Biological identity of orbital cavernous venous malformations.

Vascular anomalies comprise a wide spectrum of clinical manifestations related to disturbances in the blood or lymph vessels. They correspond to mainly tumors (especially hemangiomas), characterized by high mitotic activity and proliferation of the vascular endothelium, and malformations, endowed with normal mitotic activity and no hypercellularity or changes in the rate of cell turnover. However, the classifications of these lesions go beyond this dichotomy and consist various systems adapted for and by different clinical subgroups. Thus, the classifications have not reached a consensus and have historically caused confusion regarding the nomenclatures and definitions. Cavernous venous malformations of the orbit, previously called cavernous hemangiomas, are the most common benign vascular orbital lesions in adults. Herein, we have compiled and discussed the various evidences, including clinical, radiological, morphological, and molecular evidence that indicate the non-neoplastic nature of these lesions.

Clinical Relevance of the Variability of the Infraorbital Arterial Anatomy Evaluated by Three-Dimensional Computed Tomography.

BACKGROUND: Knowledge of the anatomy of the infraorbital artery (IOA) is crucial for the rejuvenation of the anterior medial aspect of the midface; however, studies adequately describing the anatomy of the IOA branches are lacking, and their connection with the ophthalmic artery branches remains unclear. OBJECTIVES: This study aims to elucidate the anatomical characteristics of the IOA in its deployment within the lower eyelid using three-dimensional (3D) technology, thereby offering an anatomical foundation for clinical surgical procedures. METHODS: An analysis was conducted on computed tomography scans of 132 cadaveric head sides post-contrast injection, utilizing the Mimics software for reconstruction. The study focused on examining the anastomosis of the IOA, its principal branches, and the branches emanating from the ophthalmic artery. RESULTS: The prevalence of type I IOA was observed at 38.6% (51/132), while Type II IOA was found in 61.4% (81/132) of cases. A 7.6% incidence (10/132) of IOA directly anastomosing with the angular artery was noted. The presence of palpebral branches (PIOA) was identified in 57.6% (76/132) of instances. In the lower eyelid, four distinct distribution patterns of IOA were discerned: The likelihood of Type I PIOA was 5.3%, whereas for Types IIA, IIB, and IIC PIOA, the probabilities were 8.3%, 32.6%, and 11.4%, respectively. The occurrence of the orbital branch of IOA was recorded at 41.7% (55/132). CONCLUSIONS: 3D technology can map IOA variants and identify the deployment patterns of IOA branches in the lower eyelid vascular vesicles at high resolution as a guide in clinical practice. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

[Anterior orbital ischemia secondary to type 1 cryoglobulinemia: A case report and literature review]. / Ischémie du segment antérieur de l'œil secondaire à une cryoglobulinémie de type 1 : à propos d'un cas et revue de la littérature.

INTRODUCTION: Type 1 cryoglobulinemia is characterized by a large number of clinical signs. The lack of specificity of these signs can make diagnosis difficult. Ocular manifestations are rarely described across medical literature. Only 15 cases of ophthalmological involvement secondary to cryoglobulinaemia have been reported. COMMENT: We report the case of a 69-year-old patient with cutaneous type 1 cryoglobulinaemia. He presented with bilateral anterior segment ischemia without retinal involvement with unilateral neovascularisation. Treatment of the B lymphocyte clone with rituximab and bendamustine and plasma exchange were initiated with successfully. Two similar cases describing ischaemic damage to the iris during type 1 cryoglobulinemia have been reported in the literature. CONCLUSION: Irial ischaemia should be considered as a potential in type 1 cryoglobulinaemia.

Diameters of the optic sheath and superior ophthalmic vein can expand and contract at positional changes: a magnetic resonance imaging study.

PURPOSE: This study aimed to explore the diameters of the optic sheath (OSD) and superior ophthalmic vein (SOVD) in response to positional changes using magnetic resonance imaging (MRI). MATERIALS AND METHODS: Fifty adult outpatients who presented to the hospital underwent thin-slice coronal T2-weighted MRI in the supine position followed by the prone position. RESULTS: The OS and SOV were well delineated in all the patients. The OSD in the anterior orbit was measured in the supine and prone positions on both sides. In addition, the SOVD in the anterior and posterior orbits was measured in the supine and prone positions on both sides. The OSD demonstrated an increase on both sides in 100% of the cases. The SOVD demonstrated an increase on both sides in 94% of the cases, whereas the remaining 6% demonstrated a decrease. The OSD measured at the anterior orbit and the SOVD at the anterior and posterior orbits significantly increased on both sides with positional changes from the supine to the prone position. CONCLUSION: OSD and SOVD may expand and contract in response to alterations in the intracranial pressure and venous flow patterns. MRI examination in the supine position combined with positional changes can help to better understand the OS and SOV as dynamic structures.

Endoscopic-assisted Orbitotomy for Obliteration of Orbital Arteriovenous Fistula Refractory to Endovascular Techniques.

Orbital arteriovenous fistula is a rare acquired disorder. The coincidence of arteriovenous fistula with lymphaticovenous malformation is even rarer. The optimal treatment, thus, is controversial. Surgical approaches vary widely, with associated pros and cons. The purpose of this case report is to describe an orbital arteriovenous fistula in a 25-year-old man with congenital fronto-orbital lymphaticovenous malformation, refractory to endovascular techniques, which was later successfully ablated by a direct endoscopic-assisted orbital approach.

Actualización en anomalías vasculares de la órbita en pediatría: diagnóstico por imágenes y tratamiento / Update on orbital vascular anomalies in pediatrics: imaging studies and management

Las anomalías vasculares de la órbita (AVO) son un grupo heterogéneo de patologías que pueden presentarse con frecuencia en el cono orbitario, la región periorbitaria o dentro de la órbita misma. Las AVO se dividen en tumores y malformaciones. Su presentación clínica más frecuente es el exoftalmos, asociado o no a alteración del eje visual. Además, pueden presentar complicaciones agudas, como hemorragia intralesional o celulitis entre las más frecuentes, y complicaciones crónicas, como ambliopía y afectación de la agudeza visual a largo plazo. La evolución de las técnicas de imágenes, el uso de nuevos fármacos y la utilización de innovadores procedimientos en radiología intervencionista han posibilitado obtener una mejora significativa en los procesos diagnósticos y terapéuticos de estos pacientes, permitiendo un diagnóstico y tratamiento preciso.

Orbital vascular anomalies (OVAs) are a heterogeneous group of disorders frequently found in the orbital cone, the periorbital region, or within the orbit itself. OVAs are divided into tumors and malformations. The most frequent clinical presentation is exophthalmos, associated or not with an alteration of the visual axis. They may also cause acute complications, being intralesional bleeding or cellulitis the most frequent, and chronic complications, such as amblyopia and long-term visual acuity impairment. The development of imaging techniques, the use of new drugs, and the implementation of innovative procedures in interventional radiology have resulted in a significant improvement in the diagnostic and therapeutic approaches to these patients, essential to an accurate diagnosis and management.

Orbital and ocular perfusion in thyroid eye disease.

Thyroid eye disease (TED) is characterized by enlargement of extraocular muscles, an increase in retrobulbar fat, orbital fibrosis, and fluctuations in plasma thyroid hormone levels in most patients, often associated with raised autoantibody titers. The occurrence of orbital space conflict compromises the orbital perfusion, unchecked progression of which results in irreversible loss of visual acuity and visual fields. The quantitative assessment of orbital perfusion can be done by measurement of blood flow velocities in the superior ophthalmic vein (SOV), ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary artery by color Doppler imaging. The retinal and choroidal microvasculature is studied by optical coherence tomography and optical coherence tomography angiography. The orbital and ocular perfusion fluctuates during the course of TED. Orbital congestion is reflected by the reduction or reversal of SOV flow and an increase in subfoveal choroidal thickness. The active phase is characterized by high blood flow velocities of the OA and CRA. The onset of dysthyroid optic neuropathy is associated with reduced arterial perfusion and reduction in parafoveal and peripapillary vascular density. Orbital decompression improves the SOV flow and decreases the resistivity index of CRA. Sequential evaluation of orbital hemodynamic changes can thus supplement the clinical scoring systems for monitoring and planning intervention in TED.

Update on orbital vascular anomalies in pediatrics: imaging studies and management. / Actualización en anomalías vasculares de la órbita en pediatría: diagnóstico por imágenes y tratamiento.

Orbital vascular anomalies (OVAs) are a heterogeneous group of disorders frequently found in the orbital cone, the periorbital region, or within the orbit itself. OVAs are divided into tumors and malformations. The most frequent clinical presentation is exophthalmos, associated or not with an alteration of the visual axis. They may also cause acute complications, being intralesional bleeding or cellulitis the most frequent, and chronic complications, such as amblyopia and long-term visual acuity impairment. The development of imaging techniques, the use of new drugs, and the implementation of innovative procedures in interventional radiology have resulted in a significant improvement in the diagnostic and therapeutic approaches to these patients, essential to an accurate diagnosis and management.

Las anomalías vasculares de la órbita (AVO) son un grupo heterogéneo de patologías que pueden presentarse con frecuencia en el cono orbitario, la región periorbitaria o dentro de la órbita misma. Las AVO se dividen en tumores y malformaciones. Su presentación clínica más frecuente es el exoftalmos, asociado o no a alteración del eje visual. Además, pueden presentar complicaciones agudas, como hemorragia intralesional o celulitis entre las más frecuentes, y complicaciones crónicas, como ambliopía y afectación de la agudeza visual a largo plazo. La evolución de las técnicas de imágenes, el uso de nuevos fármacos y la utilización de innovadores procedimientos en radiología intervencionista han posibilitado obtener una mejora significativa en los procesos diagnósticos y terapéuticos de estos pacientes, permitiendo un diagnóstico y tratamiento preciso.

Severe Orbital Congestion After a Brow Lift Due to an Osteodural Arteriovenous Fistula.

The authors describe a 73-year-old woman who developed worsening proptosis, binocular diplopia, and periorbital pain shortly after undergoing an open subperiosteal brow lift procedure. She was found to have a pre-existing osteodural fistula (ODF) within left frontal bone, which was draining through supraorbital vein (SOV) in cavernous sinus. When SOV was inadvertently severed during a brow lift, blood from the fistula was now redirected in the orbit. This is the first report of a decompensated ODF after a brow lift procedure. It underscores the complexity of orbital venous drainage and the importance in preserving the supraorbital and supratrochlear veins during brow lift.

Imaging of superior ophthalmic vein: A pictorial overview.

The Superior Ophthalmic Vein (SOV) is the largest vein of the orbit and represents an important orbital venous drainage pathway. SOV is well identifiable on CT and MRI, and its alterations may be a clue for differential diagnosis. In this pictorial work we illustrate the most frequent conditions in which SOV appearance may be influenced by various pathologies, providing a pictorial guide for imaging interpretation.

Central retinal artery delineation using magnetic resonance imaging.

PURPOSE: Few studies have explored the central retinal artery (CRA) using neuroimaging. Our study aimed to explore this using magnetic resonance imaging (MRI). METHODS: A total of 81 patients with intact orbital structures and visual function underwent thin-slice contrast MRI. RESULTS: The identified CRAs showed highly variable morphologies on both axial and sagittal images. On the axial images, the CRAs were detected in the right orbit in 11.1% and in the left orbit in 19.8%. The distance between the site of CRA branching from the ophthalmic artery to the posterior limit of the bulb was 18.8 ± 3.9 mm (12.8-24.6 mm) on the right and 18.9 ± 3.3 mm (14.6-26.7 mm) on the left. On the sagittal images, CRAs were detected on the right in 76.5% and on the left in 85.2%. The distance between the CRA branching site and the posterior limit of the bulb was 20.4 ± 3.8 mm (14.2-28.2 mm) on the right and 19.2 ± 3.7 mm (11.3-27.1 mm) on the left. CONCLUSIONS: Thin-sliced, contrast sagittal MRI can be used to explore the proximal part of the CRA. In particular, serial sagittal imaging may be useful for detecting the CRAs and their relationship with relevant structures.

Anastomosis between the posterior superior alveolar artery and the infra-orbital artery: a review of current terminology / Anastomosis entre la arteria alveolar superior posterior y la arteria infra-orbital: una revisión de la terminología actual

SUMMARY: The posterior superior alveolar artery (PSAA) and the infra-orbital artery (IOA) present intraosseous and extraosseous rami which form an anastomosis in the lateral wall of the maxillary sinus. This anastomosis is always present, however it has not yet been included in anatomical terminology (AT), and different terms are used in scientific communication to refer to it. The aim of this study was to carry out a review of the different terms used to name this vascular structure. A literature review was carried out on the terms used to name the anastomosis between the PSAA and IOA in imaging studies and human cadavers that assessed the presence/frequency of this anatomical structure. The search was carried out in the Medline, EMBASE and LILACS databases, in Portuguese, Spanish and English, with no date restrictions. Qualitative analysis was applied to the studies selected, analysing the terminology used to refer to the anastomosis between the PSAA and IOA. Of the 2108 original articles found, 60 were selected as potentially relevant and 54 studies were finally included for qualitative analysis. Sixteen terms were found to refer to the anastomosis between the PSAA and IOA, the most frequent being Posterior Superior Alveolar Artery (PSAA), followed by Alveolar Antral Artery (AAA). Many terms are used in the medical literature to designate the anastomosis between the PSAA and IOA, the most frequent being PSAA and AAA. There is a need to unify the terms used to designate this vascular structure, and to incorporate the selected term into anatomical terminology, in order to avoid confusion in scientific communication.

RESUMEN: La arteria alveolar superior posterior (AASP) y la arteria infra-orbital (AIO) tienen ramas intra y extra óseas que forman una anastomosis en la pared lateral del seno maxilar. Esta anastomosis está siempre presente, sin embargo, aún no ha sido incluida en la terminología anatómica (TA), por lo que en la comunicación científica se utilizan diferentes términos para referirse a ella. El objetivo de este estudio fue realizar una revisión sobre los diferentes términos utilizados para nombrar esta estructura vascular. Se realizó una revisión de la literatura sobre los términos utilizados para nombrar la anastomosis entre AASP y AIO en estudios imagenológicos y en cadáveres humanos que evaluaron la presencia/frecuencia de esta estructura anatómica. La búsqueda fue realizada en las bases de datosMedline, EMBASE y LILACS, en los idiomas portugués, español e inglés, sin restricción de fecha. Los estudios seleccionados fueron evaluados de forma cualitativa, analizando la terminología empleada para referirse a la anastomosis entre AASP y AIO. Fueron encontrados 2108 artículos originales, siendo seleccionados 60 artículos potencialmente relevantes y finalmente fueron incluidos 54 estudios para análisis cualitativo. Fueron encontrados 16 términos para referirse a la anastomosis entre AASP y AIO, siendo AASP el más frecuente seguido de arteria alveolo-antral (AAA). Son muchos los términos utilizados en la literatura médica para designar la anastomosis entre AASP y AIO, siendo AASP y AAA los más usados. La unificación de los términos utilizados para designar esta estructura vascular y su incorporación en la Terminología Anatómica contribuiría a evitar equívocos en la comunicación científica.

Three-dimensional reconstruction of the orbital retrobulbar vasculature.

PURPOSE: The retrobulbar orbital vasculature is known to be complex and variable between individuals. This study aimed to produce a method to map the retrobulbar vessels, to generate 3D reconstructions, to visualise and to improve our understanding of their complexity. METHODS: Five human orbits donated under the Human Tissue Act (2004) were fixed in formalin, decalcified in 10% formic acid, and dehydrated in acetone at -20°C. Specimens were impregnated with epoxy resin, cured, and cut into 0.3 mm sections. Sections were stained with Gomori's trichrome stain, imaged, and reconstructed using 3D reconstruction software (BioVis3D, version 3.1). RESULTS: The arterial system was reconstructed in all five specimens. The superior ophthalmic vein (SOV) and the central retinal vein (CRV) were reconstructed in four specimens. E12 sheet plastination showed excellent results for histological analysis at a macroscopic level; however, anatomical topology was not entirely preserved on a microscopic level. Gomori's trichrome stain gave excellent results in highlighting axial sections of the arterial walls and their tunics, including finer calibre vessels, thus allowing detailed reconstruction of the arterial vasculature. Miller's stain for elastin showed poor results in differentiating vessels from soft tissue; venous vasculature was poorly identified with both stains. CONCLUSIONS: This study provided a detailed anatomical model of the retrobulbar orbital vascular system, a method that can be used for further studies to form a database relating to the topography of the arterial system. These models may be employed for teaching, and possible surgery planning, for both trainees and ophthalmic surgeons.

Thrombosed orbital arteriovenous malformation in a patient with lymphangioleiomyomatosis.

A 47 year-old female with lymphangioleiomyomatosis developed right periorbital pain worsened while chewing, six months prior. Neuroimaging demonstrated a heterogenous inferotemporal right orbital mass extending through the inferior orbital fissure into the temporalis fossa, with flow voids. Given the patient's past medical history, the lesion was presumed to be a perivascular epithelioid cell tumor, a manifestation of lymphangioleiomyomatosis. A lateral orbitotomy revealed a well-circumscribed bluish-red lesion with areas of hemorrhage that was resected in total. Histopathology, however, was consistent with a thrombosed orbital arteriovenous malformation likely arising from the zygomaticotemporal neurovascular bundle. Lymphangioleiomyomatosis is a rare progressive disease that causes cystic destruction of the lungs and is frequently associated with extrapulmonary tumor infiltration, typically of the kidney and liver. Lymphangiomyoleiomyomatosis cell pathogenesis includes a pro-angiogenic micro-environment, classically expressing vascular endothelial factor-C and -D, which we postulate may have contributed to the development of the orbital arteriovenous malformation.