Anatomic Variations of Foramen Ovale as a Predictor of Successful Cannulation in Percutaneous Trigeminal Rhizotomies.

BACKGROUND AND OBJECTIVES: Percutaneous trigeminal rhizotomies are common treatment modalities for medically refractory trigeminal neuralgia (TN). Failure of these procedures is frequently due to surgical inability to cannulate the foramen ovale (FO) and is thought to be due to variations in anatomy. The purpose of this study is to characterize the relationships between anatomic features surrounding FO and investigate the association between anatomic morphology and successful cannulation of FO in patients undergoing percutaneous trigeminal rhizotomy. METHODS: A retrospective analysis was conducted of all patients undergoing percutaneous trigeminal rhizotomy for TN at our academic center between January 1, 2010, and July 31, 2022. Preoperative 1-mm thin-cut computed tomography head imaging was accessed to perform measurements surrounding the FO, including inlet width, outlet width, interforaminal distance (a representation of the lateral extent of FO along the middle fossa), and sella-sphenoid angle (a representation of the coronal slope of FO). Mann-Whitney U tests assessed the difference in measurements for patients who succeeded and failed cannulation. RESULTS: Among 37 patients who met inclusion criteria, 34 (91.9%) successfully underwent cannulation. Successful cannulation was associated with larger inlet widths (median = 5.87 vs 3.67 mm, U = 6.0, P = .006), larger outlet widths (median = 7.13 vs 5.10 mm, U = 14.0, P = .040), and smaller sella-sphenoid angles (median = 52.00° vs 111.00°, U = 0.0, P < .001). Interforaminal distances were not associated with the ability to cannulate FO surgically. CONCLUSION: We have identified morphological characteristics associated with successful cannulation in percutaneous rhizotomies for TN. Preoperative imaging may optimize surgical technique and predict cannulation failure.

Radiofrequency thermocoagulation under neuromonitoring guidance and general anesthesia for treatment of refractory trigeminal neuralgia.

OBJECTIVE: Radiofrequency thermocoagulation (RFT) for refractory trigeminal neuralgia is usually performed in awake patients to localize the involved trigeminal branches. It is often a painful experience. Here, we present RFT under neuromonitoring guidance and general anesthesia. METHOD: Stimulation of trigeminal branches at the foramen ovale with the tip of the RFT cannula is performed under short general anesthesia. Antidromic sensory-evoked potentials (aSEP) are recorded from the 3 trigeminal branches. The cannula is repositioned until the desired branch can be stimulated and lesioned. CONCLUSION: aSEP enable accurate localization of involved trigeminal branches during RFT and allow performing the procedure under general anesthesia.

Foramen ovale flap aneurysm in fetuses associated with and without heart defects: Prenatal diagnosis, imaging, in-utero hemodynamics, pregnancy, and postnatal outcomes.

BACKGROUND: Isolated redundant foramen ovale flap aneurysm (RFOA) in the absence of restrictive foramen ovale is believed to be a cause for pseudocoarctation of aorta since the impediment of blood flow to the left heart can be severe, resembling the picture of left ventricular hypoplasia with retrograde aortic flow. The primary objective of the study is to find whether RFOA is always a benign lesion. The main focus of the study is to share my experience in particular on fetuses having redundant foramen ovale flap aneurysm developing into coarctation of aorta and to study the associated factors. METHODS: Retrospective study (January 2020 to June 2023). All fetuses with RFOA associated with and without congenital heart defects were included. Fetuses with restrictive foramen ovale and RFOA with single ventricle hearts were excluded. The imaging, in-utero hemodynamics, pregnancy, and postnatal outcomes with at least 3 months follow-up were presented. RESULTS: During the study period, a total of 1499 fetal echocardiography were performed. Twenty-two fetuses with RFOA were included. Fourteen fetuses had isolated RFOA and eight had associated abnormalities [extracardiac (n = 5); intracardiac (n = 2), Both (n = 1)]. Genetic evaluation were performed only in fetuses with associated defects were normal. Postnatally all isolated RFOA fetuses had no aortic arch obstruction. Fetuses with associated aberrant right subclavian artery, isolated left superior vena cava, absent ductus venosus and ventricular septal defects developed aortic arch obstruction after birth. RFOA causes smallish left ventricle in fetuses with tetralogy of Fallot which recovered to normal size postnatally. CONCLUSION: Isolated RFOA can be benign, however, if it is associated with cardiac or extracardiac anomalies predominantly resulted in aortic arch obstruction. Though it is a cause for pseudocoarctation of aorta, through postnatal reassessment of aortic arch is mandatory. Careful search for intracardiac and systemic venous anomalies is recommended. It created confusion regarding adequacy of left ventricle when associated with congenital heart defects.

Anatomical measurements of trigeminal ganglion: a cadaver study.

It is difficult to obtain specific information regarding the trigeminal ganglion (TG), especially pediatric TG. The aim of present study was to determine the parameters of the TG and assist in the neuroablative treatment of trigeminal neuralgia (TN). Thirty-seven sides of cadaver heads that had undergone gross anatomical examination were included, with 29 sides of adults and 8 sides of infants. The distance and angles were measured among 12 points, with nine points adjacent to the TG and three points on the foramen ovale (FO). The three points on FO were represented as three different surgical approaches for TN: posterior FO approach (PFO), lateral FO approach (LFO), and anterior FO approach (AFO). A high similarity was found in pediatric TG. No statistical difference was detected in either the distance or the angles between the 12 points. Statistical difference was found in adult heads in some of the distances, which included PFO to point 5 (17.97 ± 3.35 mm in the left and 15.52 ± 2.28 mm in the right; p = 0.03) and LFO to point 5 and point 8. Moreover, the angle for PFO to point 5 showed a statistically significant difference (60.10 ± 14.02 in the left and 46.63 ± 10.48 in the right; p = 0.01). These findings revealed that surgical neuroablation for patients with TN should be performed more carefully when the PFO or LFO approach is adopted, with a precise preoperative evaluation to avoid corneal complications. Two safety radiofrequency rhizotomy points are also presented to deal with two different kinds of TN.

D-Transposition of the great arteries with restrictive foramen ovale in the fetus: the dilemma of predicting the need for postnatal urgent balloon atrial septostomy.

OBJECTIVE: Restrictive foramen ovale (FO) in dextro-transposition of the great arteries (d-TGA) with intact ventricular septum may lead to severe life-threatening hypoxia within the first hours of life, making urgent balloon atrial septostomy (BAS) inevitable. Reliable prenatal prediction of restrictive FO is crucial in these cases. However, current prenatal echocardiographic markers show low predictive value, and prenatal prediction often fails with fatal consequences for a subset of newborns. In this study, we described our experience and aimed to identify reliable predictive markers for BAS. METHODS: We included 45 fetuses with isolated d-TGA that were diagnosed and delivered between 2010 and 2022 in two large German tertiary referral centers. Inclusion criteria were the availability of former prenatal ultrasound reports, of stored echocardiographic videos and still images, which had to be obtained within the last 14 days prior to delivery and that were of sufficient quality for retrospective re-analysis. Cardiac parameters were retrospectively assessed and their predictive value was evaluated. RESULTS: Among the 45 included fetuses with d-TGA, 22 neonates had restrictive FO postnatally and required urgent BAS within the first 24 h of life. In contrast, 23 neonates had normal FO anatomy, but 4 of them unexpectedly showed inadequate interatrial mixing despite their normal FO anatomy, rapidly developed hypoxia and also required urgent BAS ('bad mixer'). Overall, 26 (58%) neonates required urgent BAS, whereas 19 (42%) achieved good O2 saturation and did not undergo urgent BAS. In the former prenatal ultrasound reports, restrictive FO with subsequent urgent BAS was correctly predicted in 11 of 22 cases (50% sensitivity), whereas a normal FO anatomy was correctly predicted in 19 of 23 cases (83% specificity). After current re-analysis of the stored videos and images, we identified three highly significant markers for restrictive FO: a FO diameter < 7 mm (p < 0.01), a fixed (p = 0.035) and a hypermobile (p = 0.014) FO flap. The maximum systolic flow velocities in the pulmonary veins were also significantly increased in restrictive FO (p = 0.021), but no cut-off value to reliably predict restrictive FO could be identified. If the above markers are applied, all 22 cases with restrictive FO and all 23 cases with normal FO anatomy could correctly be predicted (100% positive predictive value). Correct prediction of urgent BAS also succeeded in all 22 cases with restrictive FO (100% PPV), but naturally failed in 4 of the 23 cases with correctly predicted normal FO ('bad mixer') (82.6% negative predictive value). CONCLUSION: Precise assessment of FO size and FO flap motility allows a reliable prenatal prediction of both restrictive and normal FO anatomy postnatally. Prediction of likelihood of urgent BAS also succeeds reliably in all fetuses with restrictive FO, but identification of the small subset of fetuses that also requires urgent BAS despite their normal FO anatomy fails, because the ability of sufficient postnatal interatrial mixing cannot be predicted prenatally. Therefore, all fetuses with prenatally diagnosed d-TGA should always be delivered in a tertiary center with cardiac catheter stand-by, allowing BAS within the first 24 h after birth, regardless of their predicted FO anatomy.

Radiofrequency Thermocoagulation Through the Foramen Rotundum Versus the Foramen Ovale for V2 Primary Trigeminal Neuralgia: A Systematic Review and Meta-analysis.

BACKGROUND: Percutaneous radiofrequency thermocoagulation (RFT) through the foramen rotundum (FR) is a new approach for the treatment of V2 trigeminal neuralgia (TN). Some studies have shown the novel method seems to have advantages over traditional RFT through the foramen ovale (FO). The optimal interventional surgical strategy for isolated V2 TN remains controversial. OBJECTIVES: The purpose of our study was to perform a systematic review and meta-analysis to evaluate the clinical results of RFT through the FR and the traditional FO puncture approach. STUDY DESIGN: A systematic review of randomized controlled trials for thermocoagulation through the foramen rotundum versus the foramen ovale for V2 primary trigeminal neuralgia. METHODS: Randomized controlled trials or nonrandomized controlled trials published from January 2000 through October 2022 that compared RFT through the FR and the FO for V2 primary TN were found through a comprehensive search in 3 electronic databases (PubMed, EMBASE, Cochrane library). A total of 3 studies (105 patients) were included in this systematic review and meta-analysis. RESULTS: The results indicate that there are no statistically significant differences between the FR group and the FO group in terms of postoperative immediate effect rate (postoperative one week) (P > 0.1; standardized mean difference [SMD] =  0.67 [0.26- 1.71]) and recurrence rate (P > 0.1; SMD = 0.67 [0.26 - 1.71]). The long-term effect rate (postoperative one year) was significantly higher in the FR group (P < 0.05; SMD = 0.12 [0.01 - 0.22]). The FO group had a significantly higher total complication rate compared with the FR group (P < 0.01; SMD = 0.12 [0.03 - 0.53]). LIMITATIONS: The limitations of this systematic review and meta-analysis include the small range of study populations. Heterogeneity caused by inconsistent follow-up time, outcome measurements, and RF parameters are other limitations. CONCLUSION: In conclusion, RFT of the maxillary nerve through the FR for the treatment of primary V2 TN had a better long-term effect rate and fewer complications in comparison with thermocoagulation of the Gasserian ganglion through the FO. No differences were found between both interventions in terms of immediate effect rate and recurrence rate.

Predictive value of foramen ovale size on pain recurrence after percutaneous balloon compression. / 卵圆孔大小对经皮穿刺球囊压迫术后疼痛复发的预测价值.

OBJECTIVES: Primary trigeminal neuralgia (PTN) is a common cranial nerve disease in neurosurgery, which seriously endangers the physical and mental health of patients. Percutaneous balloon compression (PBC) has become an effective procedure for the treatment of PTN by blocking pain conduction through minimally invasive puncture. However, the recurrence of facial pain after PBC is still a major problem for PTN patients. Intraoperative balloon shape, pressure and compression time can affect the prognosis of patients with PBC after surgery. The foramen ovale size has an effect on the balloon pressure in Meckel's lumen. This study aims to analyse the predictive value of foramen ovale size for postoperative pain recurrence of PBC by exploring the relationship between foramen ovale size and postoperative pain recurrence of PBC. METHODS: A retrospectively analysis was conducted on the clinical data of 60 patients with PTN who were treated with PBC in Department of Neurosurgery, Affiliated Hospital of Chengde Medical College from November 2018 to December 2021. We followed-up and recorded the Barrow Neurological Institute (BNI) pain score at 1, 3, 6 and 12 months after operation. According to the BNI pain score at 12 months after surgery, the patients were divided into a cure group (BNI pain score I to Ⅱ) and a recurrence group (BNI pain score Ⅲ to Ⅴ). The long diameter, transverse diameter and area of foramen ovale on the affected side and the healthy side of the 2 groups were measured. Receiver operating characteristic (ROC) curve and area under the curve (AUC) were used for analysis the relationship between the recurrence of pain and the long diameter, transverse diameter, area of foramen ovale on the affected side, and aspect ratio, transverse diameter ratio, area ratio of foramen ovale on the affected side to healthy side in the 2 groups. RESULTS: At the end of 12 months of follow-up, 50 (83.3%) patients had pain relief (the cured group), 10 (16.7%) patients had different degrees of pain recurrence (the recurrence group), and the total effective rate was 83.3%. There were no significant differences in preoperative baseline data between the 2 groups (all P>0.05). The long diameter of foramen ovale on the affected side, the long diameter ratio and area ratio of foramen ovale on the affected/healthy side in the cured group were significantly higher than those in the recurrence group (all P<0.05), and there were no significant differences in the transverse diameter and area of foramen ovale on the affected side and the transverse diameter ratio of foramen ovale on the affected/healthy side between the 2 groups (all P>0.05). The ROC curve analysis showed that the AUC of the long diameter of foramen ovale on the affected side was 0.290 (95% CI 0.131 to 0.449, P=0.073), and the AUC of aspect ratio of foramen ovale on the affected side to healthy side was 0.792 (95% CI 0.628 to 0.956, P=0.004). The AUC of area ratio of foramen ovale on the affected side to healthy side was 0.766 (95% CI 0.591 to 0.941, P=0.008), indicating that aspect ratio and area ratio of foramen ovale on the affected side to healthy side had a good predictive effect on postoperative pain recurrence of PBC. When aspect ratio of foramen ovale on the affected side to healthy side was less than 0.886 3 or area ratio of foramen ovale on the affected side to healthy side was less than 0.869 4, postoperative pain recurrence was common. CONCLUSIONS: Accurate evaluation of the foramen ovale size of skull base before operation is of great significance in predicting pain recurrence after PBC.

Successful percutaneous cannulation of foramen ovale obstructed by completely ossified pterygoalar ligament using the Hartel approach: Two case reports.

RATIONALE: Ossification of the pterygoalar ligament, which lies inferolateral to the exocranial opening of the foramen ovale, is traditionally considered to be a bony bar that could obstruct percutaneous needle access to the foramen ovale using the Hartel approach. We herein present two case reports of successfully penetrating the foramen ovale by a needle across the pterygoalar bar. Lack of knowledge of this type of presentation might lead to a change in the surgical approach. PATIENT CONCERNS: A 27-year-old woman had an 11-year history of facial pain because of a space-occupying lesion in the left cerebellopontine angle. Neither open surgery nor drug therapy resolved her facial pain. Another 67-year-old woman developed episodic facial pain because of herpes zoster infection 20 days earlier, and she could not achieve pain relief from drug therapy. DIAGNOSES: Both patients were diagnosed with secondary trigeminal neuralgia. INTERVENTIONS: The patients underwent radiofrequency thermocoagulation of the semilunar ganglion via the foramen ovale. OUTCOMES: The three-dimensional computed tomography scan showed that the ipsilateral foramen ovale was obstructed by the pterygoalar bar. However, percutaneous needle cannulation of the foramen ovale was successful using the anterior approach. The facial pain was immediately and completely resolved without complications except for facial numbness. LESSONS: During percutaneous radiofrequency thermocoagulation for the treatment of trigeminal neuralgia, the Hartel approach can still be used when the foramen ovale is blocked by a pterygoalar bar. To our knowledge, this is the first report of such a treatment. Moreover, we herein provide specific technical recommendations to assist surgeons who may encounter such cases in the future.

Morphological variations and morphometry details of the foramen ovale in the Saudi population: a retrospective radiological study.

The foramen ovale is one of the essential foramina in the middle cranial fossa, more precisely, in the superior surface of the greater wing of the sphenoid bone. It has essential surgical and diagnostic significance since it serves as a surgical landmark, and crucial neurovascular vessels such as the mandibular nerve and accessory meningeal artery pass through it. Therefore, understanding the morphological and morphometric variations of the foramen ovale is essential for accurately identifying, diagnosing, and managing related pathologies. The study aimed to evaluate the morphological variations and morphometric details of the foramen ovale in the Saudi population. A radiological study was conducted to observe the measurements and the shapes of the foramen ovale in the skull with its anatomical variants. Retrospective data was collected from the Department of Radiology, King Fahad University Hospital, Saudi Arabia. The sample consisted of 100 human skulls from computed tomography scans, including 50 males and 50 females. The values for the mean length, width, and distance from the midline on the right side were 6.462 mm ± 1.681 mm, 4.897 ± 1.0631 mm, and 2.4565 ± 0.51275 mm, and 6.451 ± 1.6691 mm, 4.812 ± 1.0848 mm and 2.4290 ± 0.60039 mm for the left side, respectively. The foramen shape was oval in the majority (47%), followed by round shape (31%) with no bony outgrowths such as spur in the studied foramina. Furthermore, the morphometric variation between males and females was statistically insignificant (p-value>0.05). The observed variation of foramen ovale in this study has significant anatomical and clinical applications for various diagnostic and surgical procedures.

Prediction of epilepsy surgery outcome using foramen ovale EEG - A machine learning approach.

INTRODUCTION: Patients with drug-resistant focal epilepsy may benefit from ablative or resective surgery. In presurgical work-up, intracranial EEG markers have been shown to be useful in identification of the seizure onset zone and prediction of post-surgical seizure freedom. However, in most cases, implantation of depth or subdural electrodes is performed, exposing patients to increased risks of complications. METHODS: We analysed EEG data recorded from a minimally invasive approach utilizing foramen ovale (FO) and epidural peg electrodes using a supervised machine learning approach to predict post-surgical seizure freedom. Power-spectral EEG features were incorporated in a logistic regression model predicting one-year post-surgical seizure freedom. The prediction model was validated using repeated 5-fold cross-validation and compared to outcome prediction based on clinical and scalp EEG variables. RESULTS: Forty-seven patients (26 patients with post-surgical 1-year seizure freedom) were included in the study, with 31 having FO and 27 patients having peg onset seizures. The area under the receiver-operating curve for post-surgical seizure freedom (Engel 1A) prediction in patients with FO onset seizures was 0.74 ± 0.23 using electrophysiology features, compared to 0.66 ± 0.22 for predictions based on clinical and scalp EEG variables (p < 0.001). The most important features for prediction were spectral power in the gamma and high gamma ranges. EEG data from peg electrodes was not informative in predicting post-surgical outcomes. CONCLUSION: In this hypothesis-generating study, a data-driven approach based on EEG features derived from FO electrodes recordings outperformed the predictive ability based solely on clinical and scalp EEG variables. Pending validation in future studies, this method may provide valuable post-surgical prognostic information while minimizing risks of more invasive diagnostic approaches.

Effect of oval foramen restriction and premature contraction of the arterial catheter on right heart function of fetuses and infants.

Objective: The effect of fetal oval foramen restriction and premature contraction of the arterial catheter for the right heart function of fetuses and infants was studied by evaluating the right and left ventricular (RV/LV) ratios, the tricuspid annular plane systolic excursion (TAPSE) value, and the Tei index of right heart function parameters. Methods: This study was approved by the Ethics Committee of First Affiliated Hospital of Hebei North University (K20190116). We collected 257 fetuses between March 2020 and December 2021. Among these, 98 fetuses that did not have any heart abnormalities were assigned to group A, 91 fetuses with restriction of the left and right atrial channels were assigned to group B, and 68 fetuses with premature contraction of the arterial catheter were assigned to group C. The ventricular transverse diameter, the right heart TAPSE value and the Tei index of fetuses in late pregnancy and 90 days after birth were measured in the three groups, and the diagnostic value of each index for the right heart function injury was evaluated. P < 0.05 indicates significant. Results: The P-value of the TAPSE value and Tei index of infants in BC and AC groups and postnatal infants were less than 0.05, which was significant. In the BC group, the RV/LV ratio of fetuses was compared when P > 0.05, which was not significant; however, P < 0.05 after birth was considered significant. For fetuses and postnatal infants in the BC group, the RV/LV ratio was negatively associated with the TAPSE value. However, it was positively associated with the Tei index; Diagnostic test results. To predict impaired right heart function after birth, TAPSE had low diagnostic value, RV/LV and Tei index had high diagnostic value. Conclusions: Oval foramen restriction and premature contraction of the arterial catheter may affect the right heart function after birth and be related to the degree of the right heart enlargement. Although TAPSE prediction of the fetal and postnatal right heart function is limited, the RV/LV ratio and the Tei index can be used to predict impaired right heart function after birth.

Anatomical Morphology and Related Angles of Foramen Ovale: A Three-dimensional Computed Tomography Reconstruction.

This study aimed to report the three-dimensional reconstruction of the foramen ovale (FO) based on computed tomography angiography and describe its shape and related angles. A retrospective analysis of 199 adult patients who were hospitalised at the Department of Neurosurgery, The Second Affiliated Hospital of Bengbu Medical College, Bengbu, China, from January to December 2020 was conducted. The original DICOM files of patients' computed tomography scans were processed by 3D Slicer software to reconstruct the three-dimensional skull. The morphological characteristics of the FO on both sides were analysed. Their size, related angles and volumes, and the differences between the two sides and gender were compared. A total of 398 FO from 199 patients were studied. The most frequent shape of the FO was oval, accounting for 54.27%. The mean lengths of the right and the left sides were 5.40±1.51 and 5.10±1.18mm, respectively. The mean width on the right and left sides was 3.23±1.16 and 3.33±1.19 mm, respectively. The FO is most commonly oval in shape. Clinicians may use the anatomical characteristics regarding the size and shape of the FO for diagnosis and treatment. Key Words: Foramen ovale, Computed tomographic angiography, 3-Dimensional anatomy.

Analysis of Risk Factors Related to the Efficacy of Foramen Ovale Closure as a Therapy for Migraine.

This study aimed to monitor the incidence of migraine non-remission after percutaneous patent foramen ovale (PFO) closure and to discuss relevant risk factors. Recently, evidence of a relationship between the presence of PFO and migraines has been found, and PFO closure has been pointed out as a possible treatment for migraineurs.A retrospective analysis was conducted, which involved 139 patients diagnosed with PFO and associated migraine who underwent percutaneous PFO closure in The First Affiliated Hospital of Zhengzhou University from October 2019 to April 2021. All the considered patients were evaluated using the Headache Impact Test (HIT-6™) and classified with a score higher than 55 points before closure. The HIT-6™ score was re-evaluated 1-6 months after the intervention. HIT-6™ ≤ 55 was defined as headache remission (n = 93) and > 55 as headache non-remission (n = 46). A logistic regression model was developed to identify the risk factors of headache non-remission after PFO closure.The incidence of headache non-remission after PFO closure was 33.09%. Statistically significant differences were observed between the two groups as regards age and serum phosphorus level (P < 0.05). History of smoking, atrial fibrillation, absolute lymphocyte count, platelet-to-lymphocyte ratio, and interventricular septal thickness were identified as independent risk factors for headache non-remission following PFO closure, which were statistically significant (P < 0.05).

Ultrasound Guidance Combined with C-Arm Fluoroscopy in Selective Semilunar Ganglion Radiofrequency Thermocoagulation Through the Foramen Ovale for Trigeminal Neuralgia: A Randomized Controlled Trial.

OBJECTIVE: To explore the clinical value of ultrasound guidance combined with C-arm guidance during selective semilunar ganglion radiofrequency thermocoagulation via the foramen ovale for trigeminal neuralgia. METHODS: This study enrolled 48 patients diagnosed with trigeminal neuralgia between January 2021 and December 2021 in the Department of Pain Management at Xuanwu Hospital. Patients were randomly and equally divided into a C-arm-only group and an ultrasound-combined-with-C-arm (ultrasound+C-arm) group, according to a random number table. After exclusions, 42 patients were analyzed. Of these, 21 patients underwent selective semilunar ganglion radiofrequency thermocoagulation via the foramen ovale guided by the C-arm alone, whereas 21 patients underwent the same procedure guided by ultrasound combined with C-arm. The number of punctures, the amount of time elapsed until the target area of the semilunar ganglion was punctured, the cumulative dose of radiation exposure, and puncture-related complications were recorded during the operation. Numerical rating scale scores and radiofrequency thermocoagulation-related complications were evaluated preoperatively and at 1 day, 3 days, 7 days, 1 month, and 3 months after surgery. RESULTS: The number of punctures, the amount of time elapsed until the target area of the semilunar ganglion was punctured, and the cumulative dose of radiation exposure were all lower in the ultrasound+C-arm group than in the C-arm-only group (all P < 0.05). No significant differences were found in numerical rating scale scores and radiofrequency thermocoagulation-related complications between the two groups (P > 0.05). No puncture-related complications occurred in either of the groups. CONCLUSION: Ultrasound guidance combined with C-arm guidance could be safely used for puncturing the semilunar ganglion via the foramen ovale, with more efficiency and less radiation exposure than C-arm guidance alone.

A technique to facilitate the cannulation of the foramen ovale for balloon compression.

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 14 G 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.

Coronary Sinus Defect, Premature Restriction of Foramen Ovale and Cysto-Colic Peritoneal Band.

Background: Unroofed coronary sinus is a congenital cardiac anomaly usually associated with persistent left superior vena cava. Premature restriction or closure of foramen ovale is described in association with hypoplastic left heart syndrome. Abdominal peritoneal bands when present manifest clinically. Case report: A 27 years, gravida 2, presented with intrauterine fetal death at 24 weeks gestation due to fetal congestive cardiac failure, cardiomegaly and hydrops. Perinatal autopsy showed absent coronary sinus with cardiac veins draining directly into the heart. There was no persistent left superior vena cava. The foramen ovale was restricted prematurely. The ductus arteriosus was present and non-restrictive. Abdomen showed a cysto-colic peritoneal band. Conclusion: This is the first report showing a triad of (1) complete absence of coronary sinus without left superior vena cava (type-II); (2) premature restriction of foramen ovale without hypoplastic left heart; and (3) a cysto-colic peritoneal band between the gall bladder and colon.