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Patent foramen ovale (PFO) may be an underlying factor in the pathogenesis of migraine, vasospastic angina, and Takotsubo cardiomyopathy. This article reviews the role that PFO may play in each of these clinical entities and discusses potential interventions. It also proposes a novel clinical syndrome wherein PFO may be the unifying link among migraine, coronary vasospasm, and Takotsubo cardiomyopathy in predisposed individuals.

Acute mountain sickness (AMS) commonly plagues people who travel to high altitude and can be life threatening. Clinically, AMS is defined by a constellation of symptoms as outlined in the Lake Louise Criteria. The underlying etiology is thought to be related to a decrease in partial pressure of oxygen leading to tissue hypoxia. Patent foramen ovale (PFO) has been postulated to play a role in AMS through right-to-left shunt, which can worsen hypoxemia. Recent data demonstrate a higher prevalence of PFO in hikers with AMS. Future studies are needed to further elucidate the relationship between PFO and AMS.

Background: Routine Doppler study is a common tool for early diagnosis of Fetal Growth Restriction (FGR) and Small for Gestational Age (SGA) patients. It aimed to determine the role of the Foramen Ovale Pulsatility Index (FOPI) study beside routine Doppler study among patients with FGR and SGA fetuses.Methods: This prospective study was conducted on 35 FGR, 32 SGA, and 33 Appropriate for Gestational Age (AGA) fetuses. Demographic data, amniotic fluid index, neonatal outcome, and Doppler velocimetry, including Umbilical Artery Pulsatility Index (UMAPI), Uterine Artery Pulsatility Index (UTAPI), Middle Cerebral Artery Pulsatility Index (MCAPI), Ductus Venosus Pulsatility Index (DVPI), and FOPI were documented. Kolmogorov-Smirnov normality test, one-way ANOVA, Mann-Whitney U, Kruskal-Wallis, non-parametric pairwise comparisons adjusted for Bonferroni correction, Pearson correlation test, Chi square, Fisher’s exact test, and Receiver Operating Characteristic Curve (ROC) analysis with Youden’s Index (sensitivity+specificity-1) to estimate cut-off point were used to analyze the data at significance level

Background: Important neurovascular arteries, such as the auxiliary meningeal artery and mandibular nerve, travel through the foramen ovale, a crucial foramen in the middle cranial fossa that plays a crucial role in both diagnosis and surgery. Therefore, for proper therapy, diagnosis, and identification of foramen ovale-related disorders, it is critical to comprehend the morphometric and morphological differences in the foramen ovale. Aim: The purpose of this study was to evaluate the morphometry specifics and morphological differences in Indian individuals' foremen ovale. METHODS: The anatomical changes as well as the sizes and shapes of the foramen ovale in the skulls were assessed in the current radiography examination. 200 human skulls--100 male and 100 female--were evaluated for the study using computed tomography images. Results: The average foramen length, breadth, and distance from midline were 2.4563±0.51273, 4.895±10629, and 6.460±1.679 mm on the right side and 2.4288±0.60037, 4.810±1.0846, and 6.449±1.6689 mm on the left. Most research participants had oval foramen ovale shapes (47%), with round foramen ovale shapes observed in 31% of patients. None of the individuals had any spurs or other bony outgrowths. Male and female morphometric differences were statistically not significant (p>0.05). Conclusions: The current study comes to the conclusion that differences in the foramen ovale's morphology should be taken into account since they have substantial clinical anatomical variances for different surgical and diagnostic procedures. [ABSTRACT FROM AUTHOR]

BackgroundPatients who had a cryptogenic stroke (CS) suspected to be causally related to a patent foramen ovale (PFO) are candidates for percutaneous PFO closure. In such patients, it is important to screen for atrial fibrillation (AF). Limited guidance is available regarding AF monitoring strategies in CS patients with PFO addressing optimal monitoring technology and duration.AimTo provide a narrative review of cardiac rhythm monitoring in CS patients considered for PFO closure, including current practices, stroke recurrences after CS, findings from monitoring studies in CS patients, and predictors for AF detection published in the literature. To propose a personalized strategy for cardiac monitoring in CS patients, accounting for aspects predicting AF detection.Summary of reviewAF detection in CS patients is predicted by age, left atrial enlargement, prolonged PR interval, frequent premature atrial contractions, interatrial conduction block, diabetes, prior brain infarctions, leukoaraiosis, elevated B-type natriuretic peptide (BNP)/N-terminal pro B-type natriuretic peptide (NT-proBNP) levels, and a family history of AF, as well as composed scores (e.g. CHA2DS2-VASc, atrial fibrillation in embolic stroke of undetermined source (AF-ESUS)). The causal role of the PFO may be accounted for by the risk of paradoxical embolism (RoPE) score and/or the PFO-Associated Stroke Causal Likelihood (PASCAL) classification.ConclusionA personalized approach to AF detection in CS patients is proposed, accounting for the likelihood of AF detection and aimed at obtaining sufficient confidence regarding the absence of AF in patients considered for PFO closure. In addition, the impact of high-risk PFO features on the monitoring strategy is discussed.

Introducing a preoperative image simulation technique to streamline the visualization of the foramen ovale in percutaneous microcompression. Twenty-five trigeminal neuralgia patients were included in the study. Preoperative cranial computed tomography scans were processed with 3D Slicer software to create simulated fluoroscopic skulls. The angulations required for precise visualization of the foramen ovale were established via simulated anteroposterior imaging. These simulations informed the C-arm's angulations for foramen ovale targeting during surgery. The preoperative simulations accurately forecasted skull rotation angulations, aligning closely with intraoperative observations with negligible discrepancies (0–2 degrees). In 17 patients, the foramen ovale was distinctly visible, while in 8 patients, it was partially obscured yet discernible using the simulated angles. Nonvisible of the foramen ovale did not occur. Postoperative pain relief and complications were recorded. Based on our initial findings, the application of preoperative image simulation shows significant referential value in achieving accurate visualization of the foramen ovale in percutaneous microcompression for trigeminal neuralgia. [ABSTRACT FROM AUTHOR]

AbstractAimMethodsResultsConclusionA case of Eustachian tube dysfunction following percutaneous balloon compression (PBC) of the trigeminal ganglion led us to investigate aural complications of PBC and similar procedures. We aimed to clarify both the physiological effects of compression of the trigeminal ganglion on aural function and the possibility of puncture of the Eustachian tube during placement of the needle.We reviewed the anatomy of the Eustachian tube in relation to the foramen ovale and the aural structures supplied by the trigeminal nerve through cadaveric study. Following CT scanning, neuronavigation was used to guide a needle into Meckel’s cave of a cadaver. Dissection was subsequently carried out with the needle in-situ to assess the proximity of the needle to the Eustachian tube and other structures. A literature review of aural complications of foramen ovale procedures using Ovid Medline, PubMed, and Google Scholar databases was undertaken.Our literature review summarises the relationship of the Eustachian tube to the foramen ovale, the nerve supply of aural structures from the trigeminal nerve and examines previously reported post-operative aural complications. From our anatomical study, at its closest point, the needle was 7 mm from the Eustachian tube.The trigeminal nerve supplies both the tensor tympani and tensor veli palatini muscles and percutaneous procedures may, therefore, lead to aural symptoms. Also, the path of the needle is close to the Eustachian tube and can be punctured during these procedures. The authors recommend discussing aural complications during consent for these procedures. [ABSTRACT FROM AUTHOR]

• 3D-CT calculates the angle of PBC puncture. • 3D-CT calculates the depth of PBC puncture. • 3D-CT can help to adjust the pear-shaped balloon. • PBC assisted by 3D-CT can achieve good surgical results. To study the value of three-dimensional CT (3D-CT) reconstruction by comparing the surgical effects of C-arm and 3D-CT in the treatment of trigeminal neuralgia (TN) by percutaneous balloon compression (PBC). A total of 136 patients were included from May 2018 to February 2019. Among them, 65 patients underwent PBC treatment with 3D-CT and others with C-arm. During 3D-CT-guided operation, 3D-CT reconstruction software was used to analyze and measure the distances from the internal orifice of Foramen ovale (FO-I) and the external orifice of Foramen ovale (FO-E) to the top of the balloon (BT) and the petrous bone ridge (PR). The data, including the angle between the puncture needle direction and the zygomatic arch, petrous bone ridge, and slope, were used to assist the puncture and balloon plasty. Postoperative follow-up for more than five years was performed to evaluate the efficacy and pain recurrence. The distance from FO-E to PR was (2.10 ± 0.16)cm, the average distance from FO-I to BT was (2.39 ± 0.07)cm, and the average angles between the puncture needle and zygomatic arch, slope, and petrous bone ridge were (56.19 ± 5.59)°, (69.12 ± 6.92)°, and (104.49 ± 6.46)°, respectively. One (1.5 %) patient in the 3D-CT group and three (4.2 %) patients in the C-arm group failed to receive PBC treatment because of failure of FO puncture (P = 0.032).In terms of postoperative pain improvement, 3D-CT group achieved better results than the C-arm group (P = 0.043). There were no significant differences in the rates of major complications and short-term recurrence (P = 0.926) between the two groups after surgery, but the five-year recurrence rate in the 3D-CT group was lower than that in the C-arm group (P = 0.032). By guiding the angle and depth of puncture, the intraoperative application of 3D-CT reconstruction technology can improve the accuracy of foramen ovale puncture and alleviate postoperative pain, and also maintain long-term postoperative pain relief, which can be used as a potentially better guidance method to improve the surgical efficacy of PBC. [ABSTRACT FROM AUTHOR]

Background: Radiofrequency thermorhizotomy (TRZ) is an established treatment for trigeminal neuralgia (TN). TRZ can result risky and painful in a consistent subset of patients, due to the need to perform multiple trajectories, before a successful foramen ovale cannulation. Moreover, intraoperative x-rays are required. Method: TRZ has been performed by using a neuronavigated stylet, before trajectory planning on a dedicated workstation. Conclusion: Navigated-TRZ (N-TRZ) meets the expectations of a safer and more tolerable procedure due to the use of a single trajectory, avoiding critical structures. Moreover, N-TRZ is x-ray free. Efficacy outcomes are similar to those reported in literature. [ABSTRACT FROM AUTHOR]

Previous studies have suggested that an extended period of ventilation before delayed cord clamping (DCC) augments birth‐related rises in pulmonary arterial (PA) blood flow. However, it is unknown whether this greater rise in PA flow is accompanied by increases in left ventricular (LV) output and systemic arterial perfusion or whether it reflects enhanced left‐to‐right shunting across the ductus arteriosus and/or foramen ovale (FO), with decreased systemic arterial perfusion. Using an established preterm lamb birth transition model, this study compared the effect of a short (∼40 s, n = 11), moderate (∼2 min, n = 11) or extended (∼5 min, n = 12) period of initial mechanical lung ventilation before DCC on flow probe‐derived perinatal changes in PA flow, LV output, total systemic arterial blood flow, ductal shunting and FO shunting. The LV output was relatively stable during initial ventilation but increased after DCC, with similar responses in all groups. Systemic arterial flow patterns displayed only minor differences during brief and moderate periods of initial ventilation and were similar after DCC. However, an increase in PA flow was augmented with an extended initial ventilation (P < 0.001), owing to an earlier onset of left‐to‐right ductal and FO shunting (P < 0.001), and was accompanied by a pronounced reduction in total systemic arterial flow (P = 0.005) that persisted for 4 min after DCC (P ≤ 0.039). These findings suggest that, owing to increased left‐to‐right shunting and a greater reduction in systemic arterial perfusion, an extended period of ventilation before DCC does not result in greater perinatal circulatory benefits than shorter periods of initial ventilation in the birth transition. Key points: Previous studies suggest that an extended period of initial ventilation before delayed cord clamping (DCC) augments birth‐related rises in pulmonary arterial (PA) blood flow.It is unknown whether this greater rise in PA flow is accompanied by an increased left ventricular output and systemic arterial perfusion or whether it reflects enhanced left‐to‐right shunting across the ductus arteriosus and/or foramen ovale, with decreased systemic arterial perfusion.Anaesthetized preterm fetal lambs instrumented with central arterial flow probes underwent a brief (∼40 s), moderate (∼2 min) or extended (∼5 min) period of ventilation before DCC.Perinatal changes in left ventricular output were similar in all groups, but extended initial ventilation augmented both perinatal increases in PA flow, owing to earlier onset and greater left‐to‐right ductal and foramen ovale shunting, and perinatal reductions in total systemic arterial perfusion.Extended ventilation before DCC does not confer a greater perinatal circulatory benefit than shorter periods of initial ventilation. [ABSTRACT FROM AUTHOR]

Background: The foramen ovale of the sphenoid bone is located anteromedial to the foramen spinosum and posterolateral to the foramen rotundum. The morphology of the foramen ovale has been described by ambiguous terms such as almond / D shap, elongated oval, oval, round semicircular, slit, pear and truly oval. The border of the foramen ovale may be irregular and bony spurs, spines, and tubercles have been documented to project into the foramen ovale. The present study morphometric data has been reported length, width, and area of the foramen ovale and morphological shapes of foramen ovale. Materials and Methods:We have collected the adult dry skulls from first years medical and dental students in multiple medical and dental colleges. We have used digital vernier callipers for measurements to measure length and breadth. We have calculated area of foramen ovale by using formula ((3.14 X Length X Beardth)/4). We have observed the shapes and categorised as oval, round, almond and irregular. Results: In present study we have observed the morphology of foramen ovale, we found the oval shape foramen ovale in 82.33% cases, round shape in 12.33% cases, almond shape were in 3.66% cases and irregular in 1.66% cases. The area of foramen ovale was on left side was 37.13+1.54 mm and right it was 37.41+0.94mm. Conclusion: The present study may be helpful in neurosurgery practices such as unsuccessful cannulation of the foramen ovale. Despite advances in stereotactic neurosurgical imaging and technique, anatomical variation of the foramen ovale occasionally prevents successful cannulation. [ABSTRACT FROM AUTHOR]

Objective The application of the da Vinci Surgical System in neurosurgery is limited due to technical difficulties requiring precise maneuvers and small instruments. This study details the advantages and disadvantages of robotics in neurosurgery and the reachable range of the transoral approach to lesions of the skull base and upper cervical spine. Methods In a cadaver study, the da Vinci Xi robot, lacking haptic feedback, was utilized for sagittal and coronal approaches on 5 heads, facilitating dura suturing in 3, with a 30°-angled drill for bone removal. Results Perfect exposure of all the nasopharyngeal sites, clivus, sellar, and choana, including the bilateral eustachian tubes, was achieved without any external incisions using this palatal split approach of transoral robotic surgery. The time required to perform a single stitch, knot, and complete single suture in robotic suturing of deep-seated were significantly less compared to manual suturing via the endonasal approach. Conclusion This is the first report to show the feasibility of suturing the dural defect in deep-seated lesions transorally and revealed that the limit of reach in the coronal plane via a transoral approach with incision of the soft palate is the foramen ovale. This preclinical investigation also showed that the transoral robotic approach is feasible for lesions extending from the sellar to the C2 in the sagittal plane. Refinement of robotic instruments for specific anatomic sites and future neurosurgical studies are needed to further demonstrate the feasibility and effectiveness of this system in treating benign and malignant skull base lesions.

The foramen ovale is a structure that allows for the extracranial passage of multiple significant intracranial structures, most notably the mandibular branch of the trigeminal nerve (CN V3). Here we report the case of a 12-year-old male who presented to the emergency department (ED) with a two-day history of nausea and emesis and a one-day history of altered mental status. Prior to presentation, he started speaking only Spanish, which was unusual because he primarily speaks English. He was also showing signs of absence seizures. Computed Tomography (CT) showed his orthodontic wire had migrated and was entering his skull through the foramen ovale, terminating within the inferior temporal lobe. Associated with the wire was an intraparenchymal hemorrhage. Imaging indicated the sparing of the internal carotid artery and its major branches, suggesting the hemorrhage was likely venous in nature. The wire was then safely removed with no complications. Same day and follow-up neurologic exams all demonstrated no deficit in CN V3 or any of the other surrounding structures. To our knowledge, this is the first case described in the literature in which a foreign object penetrated the skull floor through the foramen ovale.

Paradoxical embolism through the foramen ovale is a rare and devastating event requiring urgent treatment. Herein, we present the case of a 23-year-old male who presented with a pulmonary embolism complicated by a left renal artery paradoxical embolism. Urgent vacuum-assisted thrombo-aspiration restored normal perfusion of the left kidney within 5 hours. The patient had a patent foramen ovale and heterozygous thrombophilia. However, a radioisotopic scan performed 2 years later revealed an unexpected decrease in left renal perfusion. Therefore, despite the angiographic success, functional evaluation using a renal scan should be performed to assess renal function.

Objective: Gasser's ganglion blockade with radiofrequency thermocoagulation is a treatment option for trigeminal neuralgia. The aim of this study was to investigate the early and late treatment results of patients with idiopathic trigeminal neuralgia who underwent Gasser's ganglion blockade with percutaneous radiofrequency thermocoagulation and to evaluate the possibilities and limitations of this treatment method. Methods: Between January 2005 and October 2020, 214 patients admitted to our clinic with a diagnosis of trigeminal neuralgia were included in this study. These patients were evaluated in terms of age, sex, involved side, involved branch, early intervention results, pain-free periods, and complications. Results: Two hundred and seventy five procedures were performed in 214 patients. Of the patients, 125 (58.41%) were female and 89 (41.59%) were male. The mean age was 58.48±14.07 years. Pain was predominantly on the right side (61.68%). The most commonly involved trigeminal nerve branch group was V2-V3 (35.98%). The early success rate after radiofrequency thermocoagulation was 93.09%. At the end of the 36-month follow-up, 78.12% of the patients had no recurrence of pain. Conclusion: Although there were some differences in the involved branch of the trigeminal nerve, the results were concentrated on V2 and V2-V3. Early results were consistent with those reported in the literature. When the late-term results were evaluated, differences were observed in the follow-up periods. The complications were consistent with those reported in the literature. In conclusion, radiofrequency thermocoagulation in trigeminal neuralgia is a safe, low complication rate, and recurrent treatment method with correct indication and application. [ABSTRACT FROM AUTHOR]

Copyright of Acta Médica Peruana is the property of Colegio Medico del Peru and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The assessment of cranial foramina is an important part of the objective diagnostic and therapeutic study relevant to pathologies involving structures of the skull base. The study of the foramen ovale not only holds significance for anatomical development but also bears profound surgical importance, such as in trigeminal neuralgia, and diagnostic importance in tumors and various types of epilepsy. It becomes relevant in fine-needle aspiration techniques in perineural tumor procedures, for electroencephalographic analysis in seizures, and therapeutic procedures such as percutaneous trigeminal rhizotomy for trigeminal neuralgia. Methods: A cross-sectional study at the Department of Neurosurgery, Specialties Hospital, La Raza National Medical Center, Mexico City, involved 70 patients aged >18 years who underwent a single skull computed tomography scan between July 2023 and March 2024. Patients with sufficient scan quality and optimal visualization of skull base foramina were included in the study. Measurements of tomographic images were taken using Inobitec's DICOM file viewer. Data analysis in Microsoft Excel yielded mean, standard deviation, and 95% confidence interval (CI) for morphometric parameters of the foramen ovale. Results: Analysis of tomographies from 70 patients revealed a total of 140 foramen ovale, evenly split between 25 males (35.7%) and 45 females (64.3%). The measurements for the maximum anteroposterior diameter, transverse diameter, and surface area of all foramina were as follows: 6.61 ± 0.25 mm (95% CI), 3.97 ± 0.21 mm (95% CI), and 20.84 ± 1.58 mm2 (95% CI), respectively. Specific measurements for the right and left sides were obtained: for the right side, 6.59 ± 0.26 mm (95% CI) and 3.89 ± 0.21 mm (95% CI) for the maximum anteroposterior and transverse diameters, respectively, and 20.38 ± 1.62 mm2 (95% CI) for the surface area. For the left side, the measurements were 6.63 ± 0.24 mm (95% CI), 4.05 ± 0.21 mm (95% CI), and 21.31 ± 1.55 mm2 (95% CI) for the maximum anteroposterior diameter, transverse diameter, and surface area, respectively. The maximum and minimum dimensions for anteroposterior and transverse diameters were 10.67 mm, 4.41 mm, 7.09 mm and 2.36 mm, respectively, with a corresponding range for the surface area of 10.16 mm2-44.13 mm2. The average minimum distance between the foramen ovale and the foramen spinosum was 2.32 ± 0.24 mm (95% CI). In males, the average size of the foramen ovale was 23.66 ± 1.61, which was 22% larger than the average size in females (19.28 ± 1.45) (P = 0.0001). Conclusion: The foramen ovale is one of the main anatomical structures of the skull base, and besides that, it is complex and not directly accessible for clinical evaluation, useful information can be obtained through morphometric analysis. The present study provides specific anatomical data with morphological patterns to increase the understanding of the characteristics of the foramen ovale in the Mexican population. These are intended to be helpful in the pursuit of acknowledging the morphometrics and thus being able to plan neurosurgical procedures in the middle cranial fossa. [ABSTRACT FROM AUTHOR]

Patent foramen ovale (PFO) is closely related to neurological diseases such as stroke, migraine, obstructive sleep apnea syndrome (OSAS) and decompression sickness (DCS). It has been suggested that PFO closure could be effectively prevent and treat these neurological diseases. This article focus on exploration of the pathogenesis, epidemiology and clinical characteristics of neurological diseases related to PFO, and to discuss the potential complexity and future development of PFO closure for the treatment of these diseases. The aim is to provide guidance for the diagnosis and treatment of neurological diseases related to PFO. [ABSTRACT FROM AUTHOR]

Objective To investigate the clinical efficacy and application value of an improved 3D-printed guide plate for the treatment of primary trigeminal neuralgia (PTN) by percutaneous microballoon compression (PMC). Methods This prospective study included 42 patients with primary trigeminal neuralgia treated at the Department of Stomatology, Xuzhou Central Hospital, from September 2019 to January 2022. The group was divided by the random number table method into the experimental group (adopting 3D printing technology to make guide plates to guide the puncture, 22 cases) and the control group (adopting the traditional Hartel anterior approach to position the puncture, 20 cases). The intraoperative success rate of the first puncture, puncture time, operative time, radiation exposure of patients and postoperative complications were compared between the two groups. Postoperative Barrow Neurological Institute Scale (BNI) scores, facial numbness, diminished corneal reflexes and chewing weakness were recorded. The t-test, rank-sum test and chi-square test were used for statistical analysis, with P0.05). In the experimental group, 16 patients had postoperative masseter weakness, 1 had keratitis and 10 had perilabial herpes, while in the control group, 18 patients had postoperative masseter weakness, 2 had keratitis, 11 had perilabial herpes and 1 had monocular blindness. There was no significant difference in postoperative complications between the two groups (P>0.05). At 12 months of follow-up, there was no recurrence in either the experimental or control group. Conclusions 3D digital guide plate-guided percutaneous microballoon compression for primary trigeminal neuralgia can improve the accuracy and safety of puncture to a certain extent, obviously shorten the operation time, reduce radiation exposure of the patients, improve the success rate of the operation, meaning it has a high clinical application value.

PurposeThe mechanisms of brain metastasis are incompletely understood. Circulating tumor cells travel to the right heart and through the pulmonary circulation, where they may become lung metastases, and can circulate further to the left heart and brain. In patients who develop brain metastases without lung involvement, we hypothesized that cancer cells may travel directly from the right atrium to left atrium via a patent foramen ovale (PFO), akin to paradoxical embolism. If the prevalence of PFO is greater in these individuals compared to the general population (20-30%), PFO may play a role in brain metastasis, and prophylactic closure may provide benefit. Accordingly, we investigated the prevalence of PFO in patients with brain metastases without prior lung involvement.MethodsWe prospectively identified patients with brain metastases from a non-lung primary cancer with no preceding or concurrent lung involvement. Nine eligible participants underwent a transcranial Doppler study with intravenous agitated saline to assess for PFO.ResultsAmong nine participants, primary cancers were breast (n = 6), upper gastrointestinal (n = 2), and thyroid (n = 1). A positive bubble study was identified in 2/9 (22.2%) participants: one female with breast cancer and one male with duodenal adenocarcinoma. No participants developed lung metastases on subsequent chest imaging.ConclusionIn this prospective pilot study, we found a similar prevalence of PFO in patients who developed brain metastases without preceding lung involvement compared to estimates for the general population. Through a larger study is needed, the development of brain metastases in these individuals may primarily reflect tumor-specific biological factors diecting metastasis organotropism.

Percutaneous closure of the patent foramen ovale (PFO) is increasingly performed in specific patients with cryptogenic stroke or clinical evidence of a paradoxical embolism. This study was performed to determine the safety of same-day discharge (SDD) following such procedures. This is a prospective, observational study of patients undergoing elective percutaneous PFO closure in a single tertiary center in Portugal between January 2020 and July 2023. AmplatzerTM devices (St. Jude Medical, St. Paul, MN, USA) and NobblestichTM EL (HeartStitch, Inc., Fountain Valley, CA, USA) were used. After 6 months, the following events were looked at: post-procedural paroxysmal atrial fibrillation, stroke, unplanned cardiac re-hospitalization, urgent cardiac surgery, major vascular complications, pericardial effusions, device embolization, and death. We studied 122 consecutive patients (52% female, 68; 48±12 years old) who had elective percutaneous closure with success and no complications. Forty-nine (40%) had SDD. AmplatzerTM devices were used more frequently in the SDD group, while NobblestichTM EL was more common in the overnight group. During the overnight group's follow-up period, there was one non-cardiovascular death; there were no further events. SDD after elective percutaneous closure of PFO was shown to be a safe and successful patient management method, including NobblestichTM, which we describe for the first time. Our results prove the safety of this same-day discharge strategy. We hypothesize that in the near future, in selected cases, PFO closure might become an ambulatory procedure.

The article addresses the complex issue of differential diagnosis of disproportion in the four-chamber view of the fetal heart during late pregnancy. Topics discussed include physiological versus pathological causes of ventricular disproportion, diagnostic techniques for distinguishing these causes, and the implications of these findings for prenatal and postnatal care.

BackgroundAlthough observational studies have shown percutaneous patent foramen ovale (PFO) closure to be a safe means of reducing the frequency and duration of migraine, randomized clinical trials have not met their primary efficacy endpoints.ObjectivesThe authors report the results of a pooled analysis of individual participant data from the 2 randomized trials using the Amplatzer PFO Occluder to assess the efficacy and safety of percutaneous device closure as a therapy for episodic migraine with or without aura.MethodsThe authors analyzed individual patient-level data from 2 randomized migraine trials (the PRIMA [Percutaneous Closure of Patent Foramen Ovale in Migraine With Aura] and PREMIUM [Prospective Randomized Investigation to Evaluate Incidence of Headache Reduction in Subjects with Migraine and PFO Using the Amplatzer PFO Occluder Compared to Medical Management] studies). Efficacy endpoints were mean reduction in monthly migraine days, responder rate (defined as ≥50% reduction in monthly migraine attacks), mean reduction in monthly migraine attacks, and percentage of patients who experienced complete cessation of migraine. The safety endpoint was major procedure- and device-related adverse events.ResultsAmong 337 subjects, 176 were randomized by blocks to device closure and 161 to medical treatment only. At 12-month follow-up, the analysis met 3 of the 4 efficacy endpoints: mean reduction of monthly migraine days (-3.1 days vs. -1.9 days; p = 0.02), mean reduction of monthly migraine attacks (-2.0 vs. -1.4; p = 0.01), and number of subjects who experienced complete cessation of migraine (14 [9%] vs. 1 [0.7%]; p

Background: Percutaneous balloon compression is a safe and effective treatment for trigeminal neuralgia. Current technique consists of penetrating the foramen ovale using a sharp 14G needle with a stylet. Difficulty of cannulation of the foramen ovale, failures of cannulation and major neurovascular complications of the procedure, although rare, may be due to the relatively large caliber of this needle and its sharp tip. Objective: To present a novel technique to facilitate and make the cannulation of the foramen ovale with a 14G cannula safer. Methods: A rigid blunt-tip guide of 1.2 or 1.5 mm is used to penetrate the foramen ovale under lateral fluoroscopic control. Once the guide enters the foramen it is advanced further to the clival line, and a 14G cannula is then advanced over the guide to engage the foramen, at which point the guide is withdrawn and replaced with the balloon catheter. Results: The technique was employed to deliver a 4F balloon catheter to Meckel's cave successfully in 500 consecutive procedures performed on 416 trigeminal neuralgia patients. None of the patients had neurovascular complications like facial hematoma, arterial injury, carotid-cavernous fistula or cranial nerve palsies. Conclusion: A novel technique for cannulation of the foramen ovale is described. The use of blunt tip guides of smaller diameters instead of sharp 14G needles considerably facilitated cannulation of the foramen ovale and enabled cannulation in all cases. Absence of complications of cannulation such as facial hematoma, carotid-cavernous fistula or intracranial hemorrhage in this series of patients suggests that the technique may be safer than the use of conventional sharp tipped 14G needles in terms of avoiding neurovascular complications. [ABSTRACT FROM AUTHOR]

Background and Hypothesis: The objective of this study was to identify the characteristics of electrocardiogram (ECG) in adult patients with patent foramen ovale (PFO) and to analyze the predictive value of the characteristics of ECG for PFO in adult patients. Methods: Retrospectively, 267 patients who had undergone ECG, transthoracic echocardiography (TTE), transesophageal echocardiography (TEE) with agitated saline contrast echocardiography in our hospital, were recruited continuously from January 2021 to March 2023. Electrocardiographs were analyzed to investigate the presence of right bundle branch block (RBBB) and crochetage R wave. Results: The ratio of crochetage R wave in inferior leads in patients with PFO was 45.3% and 21.2% without PFO. There were 17 (6.4%) patients with coexistence of crochetage R wave and RBBB, including 13 (6.5%) patients with PFO and four (6.1%) patients without PFO. The accuracies of TTE, crochetage R wave, and RBBB were 0.637, 0.535, and 0.314, respectively. A combination of crochetage R wave and RBBB demonstrated a sensitivity of 0.507 and a specificity of 0.758. When TTE, crochetage R wave, and RBBB were combined, the accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were 0.712, 0.801, 0.439, 0.813, and 0.420, respectively. Logistic regression analysis revealed a correlation between PFO and the presence of crochetage R wave (odds ratio [OR]: 3.073, 95% confidence interval [CI]: 1.601–5.899, p < 0.001), and also a combination between crochetage R wave and RBBB (OR: 3.220, 95% CI: 1.720–6.028, p < 0.001). Conclusions: Crochetage R wave in ECG was associated with PFO. Crochetage R wave, especially combined with RBBB and TTE, may be helpful in the early detection of patients with PFO. [ABSTRACT FROM AUTHOR]

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Background: The pathogenesis of concomitant continuous pain remains unclear and is worthy of further study. In this clinical study, we aimed to explore the potential role of a narrow foramen ovale in the development of concomitant continuous pain. Methods: A total of 108 patients with classical trigeminal neuralgia affecting the third branch of the trigeminal nerve and 46 healthy individuals were enrolled in this study. Three-dimensional reconstructed computerized tomography images of all participants were collected, and the morphometric features of the foramen ovale were examined by two investigators who were blinded to the clinical data of the patients. Results: In this cohort, patients with concomitant continuous pain suffered from more sensory abnormalities (18.4% vs. 2.9%, p = 0.015) and responded more poorly to medication (74.3% vs. 91.9%, p = 0.018) than patients without concomitant continuous pain. While no significant differences regarding the mean length (5.02 mm vs. 5.36 mm, p > 0.05) and area (22.14 mm² vs. 23.80 mm², p > 0.05) were observed between patients with and without concomitant continuous pain, the mean width of the foramen ovale on the affected side in patients with concomitant continuous pain was significantly narrower than that in patients without concomitant continuous pain (2.01 mm vs. 2.48 mm, p = 0.003). Conclusion: This neuroimaging and clinical study demonstrated that the development of concomitant continuous pain was caused by the compression of the trigeminal nerve owing to a narrow foramen ovale rather than responsible vessels in classical trigeminal neuralgia. [ABSTRACT FROM AUTHOR]

For the treatment of trigeminal neuralgia, the foramen ovale is reached by entering the cheek with a needle. Thermocoagulation is performed with balloon compression, administration of alcohol or radiofrequency. Apart from the classical method, it is theoretically possible to reach the foramen ovale through the mouth with the anterior approach. In our study, it was aimed to examine horizontally and vertically the angular values that must be given to the needle to reach the foramen ovale in the anterior approach. Three landmark points were determined on both right and left sides of 25 dry skulls. A rod was inserted starting from these landmark points and passing through the center of the foramen ovale. The vertical and horizontal angular values of this bar were measured. For each foramen ovale, 3 vertical angles, 3 horizontal angles and 4 distance measurements were made. There was a significant difference between the right and left sides in terms of horizontal angular values. Average values of horizontal angles (in degrees); on the right, 7.29 for H1, 12.15 for H2, 32.29 for H3; 1.26 for H1, 9.46 for H2, and 30.56 for H3 on the left side (p<0.005). The angle value was measured as 0 or negative value in 5 (20 %) of the H1 angle measurements made on the right side and 14 (56 %) on the left side. The H2 angle value was found to be smaller than the H1 angle in the skull 2 (8 %) on the right and 3 (12 %) on the left. There was no difference between the right and left sides in terms of vertical angular values. A significant difference was found between the right and left sides in the D1, D2, D4 distances (p<0.005). Six important anatomical features affecting angular values were encountered. [ABSTRACT FROM AUTHOR]

Introduction: Pterygoalar bar (PTAB) is a bony bridge formed by the incomplete or complete ossification of the pterygoalar ligament extending between the lateral pterygoid lamina (LPL) and the greater wing of the sphenoid bone. Complete ossification of the pterygoalar ligament results in the formation of the so-called "pterygoalar foramen" (PTAF) or Hyrtl's foramen. On the other hand, pterygospinous bar (PTSB) is another bony bridge resulting from incomplete or complete ossification of the pterygospinous ligament, which extends from the pterygospinous process of the LPL to the sphenoidal spine. Complete ossification of this ligament forms the pterygospinous foramen (PTSF) or the Civinini's foramen. This study was undertaken to examine detailed anatomy and incidence of PTAB, PTSB, and the corresponding foramina, as well as to establish their relationship with foramen ovale (FO). Materials and Methods: A total of 152 dry adult human skulls (304 sides) obtained from the collection of the Anatomy Department of Dokuz Eylül University were examined in terms of the presence/absence of PTAB/PTSB, their incidence and side, degree of ossification (complete/incomplete), and their relationship with FO. The distance between the spinous processes was measured in cases with incomplete ossification of PTAB/PTSB, whereas a digital caliper with 0.01 mm sensitivity (Mitutoyo, Japan) was used to measure horizontal and vertical diameters of the foramina in cases with complete ossification (i.e., when PTAF and PTSF were present). SPSS 22.0 statistical software was used for statistical analysis with Student's t-test and Pearson's correlation analysis. The level of significance was set at P < 0.05. Results: Of the 152 skulls, 11 (7.23%) harbored PTAF and 2 harbored PTSF (1.3%). An incomplete PTAB or incomplete PTSB was present in 110/304 (33.4%) and 21/304 (6.9%) of the sides examined, respectively. PTAB was located medial, lateral, inferior, inferolateral, and inferomedial to FO in 15 (4.93), 29 (9.53%), 77 (25.32%), 28 (9.21%), and 3 (0.98%) of the sides. The distance between PTAB and FO was 7.43 ± 2.58 mm on the right and 7.51 ± 2.50 mm on the left. The distance between two PTABs was 10.43 ± 3.65 mm on the right and 10.29 ± 3.30 mm on the left. The vertical diameter of PTAF was 3.80 ± 2.08 mm, and the horizontal diameter was 4.96 ± 2.24. In the presence of a foramen, the mean thickness of PTAB was 2.27 ± 0.74 mm, the mean width was 3.45 ± 3.40 mm, and the mean length was 6.54 ± 3.64 mm. No significant differences were identified between right- and left-sided measurements (P > 0.05). Discussion and Conclusion: Close adjacency of PTAB/PTSB to FO as well as their ability to form foramina may hamper the procedures requiring placement of transcutaneous needles into FO or may present anatomical challenges in surgery involving the base of the cranium. Owing to the possibility of neural compression, they may also have clinical significance for craniofacial neurosurgeons, anesthesiologists, radiologists, and dental surgeons. Our results may provide some anatomical insights for planning infratemporal fossa surgery. [ABSTRACT FROM AUTHOR]

Background: Percutaneous radiofrequency thermocoagulation (RFTC) has been widely utilized in the management of trigeminal neuralgia. Despite using image guidance, accurate needle positioning into the target area still remains a critical element for achieving a successful outcome. This study was performed to precisely clarify the anatomical information required to ensure that the electrode tip is placed on the sensory component of the mandibular nerve (MN) at the foramen ovale (FO) level. Methods: The study used 50 hemi-half heads from 26 South Korean adult cadavers. Results: The cross-sectioned anterior and posterior divisions of the MN at the FO level could be distinguished based on an irregular boundary and color difference. The anterior division was clearly brighter than the posterior one. The anterior division of the MN at the FO level was located at the whole anterior (38.0%), anteromedial (6.0%), anterior center (8.0%), and anterolateral (22.0%) parts. The posterior division was often located at the whole posterior or posterolateral parts of the MN at the FO level. The anterior divisions covered the whole MN except for the medial half of the posterolateral part in the overwrapped images of the cross-sectional areas of the MN at the FO level. The cross-sectional areas of the anterior divisions were similar in males and females, whereas those of the posterior divisions were significantly larger in males (P = 0.004). Conclusions: The obtained anatomical information is expected to help physicians reduce unwanted side effects after percutaneous RFTC within the FO for the MN. [ABSTRACT FROM AUTHOR]

BackgroundPatent foramen ovale (PFO) is implicated in the pathogenesis of clinical conditions such as cryptogenic stroke and migraine with aura. This study evaluated the challenges of sizing a PFO with different contemporary imaging modalities and assessed the relationship between PFO size and severity of the right-to-left shunt (RLS).MethodsPatients who were referred to interventional cardiology with the diagnosis of a PFO and had undergone intra-procedural balloon sizing (n = 147), transesophageal echocardiogram (TEE) imaging (n = 67), or intracardiac echocardiogram (ICE) imaging (n = 73) at the time of workup were included in this study. TEE and ICE were used to obtain PFO length and height during normal respiration. A sizing balloon was used to obtain PFO width and height after the septum primum was opened with balloon inflation.ResultsThe mean PFO length measured by TEE and ICE differed significantly (n = 27, 13.0 ± 4.1 vs. 9.9 ± 3.2 mm, p = .001). The mean PFO height measured by TEE and ICE (n = 27, 1.4 ± 0.6 vs. 1.7 ± 0.6 mm, p = .04), TEE and sizing balloon (n = 56, 1.5 ± 1.2 vs. 10.5 ± 4.2 mm, p

Background and purposeIn patients with cryptogenic stroke and patent foramen ovale (PFO), the Risk of Paradoxical Embolism (RoPE) Score has been proposed as a method to estimate a patient-specific "PFO-attributable fraction"-the probability that a documented PFO is causally-related to the stroke, rather than an incidental finding. The objective of this research is to examine the relationship between this RoPE-estimated PFO-attributable fraction and the effect of closure in 3 randomized trials.MethodsWe pooled data from the CLOSURE-I (Evaluation of the STARFlex Septal Closure System in Patients With a Stroke and/or Transient Ischemic Attack due to Presumed Paradoxical Embolism through a Patent Foramen Ovale), RESPECT (Randomized Evaluation of Recurrent Stroke Comparing PFO Closure to Established Current Standard of Care Treatment), and PC (Clinical Trial Comparing Percutaneous Closure of Patent Foramen Ovale [PFO] Using the Amplatzer PFO Occluder With Medical Treatment in Patients With Cryptogenic Embolism) trials. We examine the treatment effect of closure in high RoPE score (≥7) versus low RoPE score (

Percutaneous patent foramen ovale (PFO) closure is recommended for secondary prevention of paradoxical embolism through a PFO. In the United States, two Food and Drug Administration-approved PFO closure devices are currently available, and the choice depends on operator preference and PFO anatomy. Although these devices are easy to implant, there are several potential complications. As opposed to the Amplatzer PFO Occluder, there has been no published case of atrial erosion with Gore closure devices. This report describes two cases of pericardial tamponade due to perforation of the atrial wall induced by a wire frame fracture of the Gore Helex and Cardioform devices.

ImportanceRecent epidemiologic and therapeutic advances have transformed understanding of the role of and therapeutic approach to patent foramen ovale (PFO) in ischemic stroke. Patent foramen ovale is likely responsible for approximately 5% of all ischemic strokes and 10% of those occurring in young and middle-aged adults.ObservationsRandomized clinical trials have demonstrated that, to prevent recurrent ischemic stroke in patients with PFO and an otherwise-cryptogenic index ischemic stroke, PFO closure is superior to antiplatelet medical therapy alone; these trials have provided some evidence that, among medical therapy options, anticoagulants may be more effective than antiplatelet agents.Conclusions and relevanceThese new data indicate a need to update classification schemes of causative mechanisms in stroke, developed in an era in which an association between PFO and stroke was viewed as uncertain. We propose a revised general nomenclature and classification framework for PFO-associated stroke and detailed revisions for the 3 major stroke subtyping algorithms in wide use.

BackgroundResidual shunt is observed in up to 25% of patients after patent foramen ovale (PFO) closure, but its long-term influence on stroke recurrence currently is unknown.ObjectiveTo investigate the association of residual shunt after PFO closure with the incidence of recurrent stroke and transient ischemic attack (TIA).DesignProspective cohort study comparing stroke or TIA recurrence in patients with and without residual shunt after PFO closure.SettingSingle hospital center.Participants1078 consecutive patients (mean age, 49.3 years) with PFO-attributable cryptogenic stroke who were undergoing percutaneous PFO closure were followed for up to 11 years.MeasurementsResidual shunt was evaluated by transthoracic echocardiography with saline contrast. Primary outcome was a composite of the first recurrent ischemic stroke or TIA after PFO closure.ResultsCompared with complete closure, the presence of residual shunt after PFO closure was associated with an increased incidence of recurrent stroke or TIA: 2.32 versus 0.75 events per 100 patient-years (hazard ratio [HR], 3.05 [95% CI, 1.65 to 5.62]; P < 0.001). This result remained robust after adjustment for important covariates, namely age; study period; device; presence of atrial septal aneurysm, hypertension, hyperlipidemia, diabetes, hypercoagulability, or hypermobile septum; and medication use (HR, 3.01 [CI, 1.59 to 5.69]; P < 0.001). Further stratification based on shunt size revealed that moderate or large residual shunts were associated with a higher risk for stroke or TIA recurrence (HR, 4.50 [CI, 2.20 to 9.20]; P < 0.001); the result for small residual shunts was indeterminate (HR, 2.02 [CI, 0.87 to 4.69]; P = 0.102).LimitationNonrandomized study with potential unmeasured confounding.ConclusionAmong patients undergoing PFO closure to prevent future stroke, the presence of residual shunt, particularly a moderate or large residual shunt, was associated with an increased risk for stroke or TIA recurrence.Primary funding sourceNational Institutes of Health.

Abstract Objectives This study aims to discuss the availability of robot-assisted percutaneous balloon compression (PBC) for trigeminal neuralgia (TN) and share our preliminary experiences. Methods Patients with TN who underwent robot-assisted PBC from June to September 2022 were enrolled. We designed a fixing plug for robot-assisted PBC, three-dimensional structured light registration was used, puncture trajectory was the line connects the medial third of inner and outer aperture of foramen ovale. Numerical Rating Scale (NRS), Barrow Neurological Institute (BNI) pain and numbness intensity score were used to evaluate the facial pain and numbness. Results Eventually, nine patients were enrolled, the structured light registrations were successfully finished in all patients with a mean registration error of 0.68 mm. All the punctures of foramen ovales were successfully done one-time. Of note, the balloons were all got pear-shaped followed by 150 to 180 s compression. Though, postoperatively, all the patients complained of facial numbness and four patients suffered from transient masseter weakness, all patients got fully or mostly pain relief. It should be noted that is the numbness and weakness gradually relieved during follow-up. Conclusion Three-dimensional structured light registration and robot assisted PBC is an effective choice for patients with TN. Extension line between the medial third of the inner and outer aperture of foramen ovale might be a safe and effective puncture trajectory to this procedure.

Context: The foramen ovale is an obliquely placed, oval-shaped opening at the base of the skull in the greater wing of sphenoid. As the foramen transmits mandibular nerve, accessory meningeal artery, lesser petrosal nerve, and emissary veins, it knowledge of its variations is of supreme interest for surgeons. Aims: The aim of this study is to study the metric and nonmetric variations, of the foramen ovale of 40 dry adult human dried skulls. Settings and Design: The study was conducted in the dissection hall of Chettinad Academy of Research and Education. The study undertaken here is an observational study. Subjects and Methods: Human skulls were studied for location, patency, and various morphometric parameters bilaterally. The materials used were thin copper wire and a digital Vernier caliper of precision 0.01 mm. Statistical Analysis Used: Metric and nonmetric data were analyzed using the SPSS software. Results: The shape of foramen ovale was D shaped in most of the skulls (35%) followed by almond (21%), elongated oval (15%), and oval shape (11%). The presence of bony variations like spur was seen in 27.5% foramina, bony septa in 3.75%, and duplication in 21.25% foramina. The mean length and width of foramen ovale were 6.51 ± 1.24 mm and 3.66 ± 0.82 mm on right and 6.59 ± 1.33 mm and 3.75 ± 0.68 mm on the left, respectively. The mean area of foramen ovale was 19.08 ± 5.71 mm2 and 17.88 ± 5.85 mm2 on the right and the left, respectively. Conclusions: A sound knowledge on the morphometric variations of the foramen ovale helps the operating surgeon to avoid damage to the adjacent structures.

Background: Meningioma is a common non-glial tumor of the brain. Extracranial meningiomas in the parapharyngeal space are especially rare. Herein we report a case of extracranial meningioma in the parapharyngeal space and give a comprehensive description of its complete clinical course and radiological findings, which may provide helpful information in the diagnosis and treatment of extracranial meningiomas in the parapharyngeal space. Case Presentation: A 61-year-old man presented a slowly increased mass under the left ear without pain and numbness over one year. Ultrasound examination detected a hypoechoic uneven mass behind the left parotid gland with a clear boundary, and color Doppler flow imaging revealed blood flow signals within the mass. Unenhanced computed tomography (CT) of the craniofacial region revealed a homogenous soft tissue mass in the parapharyngeal space without calcification. Magnetic resonance imaging (MRI) showed that a homogenous soft tissue mass was hyperintense on T2-weighted image, hypointense on T1- weighted image, and obviously enhanced after contrast enhancement in the parapharyngeal space. Coronal MRI showed that the lesion originated from basicranial dura extending into parapharyngeal space through the left foramen ovale at the skull base. Finally, histopathological and immunohistochemical analyses confirmed the final diagnosis of extracranial meningiomas in the parapharyngeal space. Conclusion: Extracranial meningiomas of the parapharyngeal space are rare and often pose a diagnostic challenge. Preoperative imaging examinations, especially CT and MRI, can aid in the accurate preoperative diagnosis, especially when intracranial extensions and dural tail signs are observed. [ABSTRACT FROM AUTHOR]

Purpose: Dilatation of the trigeminal cavum, or Meckel's cave (MC), is usually considered a radiological sign of idiopathic intracranial hypertension. However, the normal size of the trigeminal cavum is poorly characterized. In this study, we describe the anatomy of this meningeal structure. Methods: We dissected 18 MCs and measured the length and width of the arachnoid web and its extension along the trigeminal nerve. Results: Arachnoid cysts were clearly attached to the ophthalmic (V1) and maxillary (V2) branches until they entered the cavernous sinus and foramen rotundum, respectively, without extension to the skull base. Arachnoid cysts were close to the mandibular branch toward the foramen ovale, with a median anteromedial extension of 2.5 [2.0–3.0] mm, lateral extension of 4.5 [3.0–6.0] mm, and posterior extension of 4.0 [3.2–6.0] mm. The trigeminal cavum arachnoid had a total width of 20.0 [17.5–25.0] mm and length of 24.5 [22.5–29.0] mm. Conclusion: Our anatomical study revealed variable arachnoid extension, which may explain the variability in size of the trigeminal cavum in images and calls into question the value of this structure as a sign of idiopathic intracranial hypertension. The arachnoid web extends beyond the limits described previously, reaching almost double the radiological size of the cavum, particularly at the level of V3 afference of the trigeminal nerve. It is possible that strong adhesion of the arachnoid to the nerve elements prevents the formation of a true subarachnoid space that can be visualized by magnetic resonance imaging. [ABSTRACT FROM AUTHOR]