scholarly journals A Segmentation Method of Foramen Ovale Based on Multiatlas

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Jiashi Zhao ◽  
Huatao Ge ◽  
Wei He ◽  
Yanfang Li ◽  
Weili Shi ◽  
...  

Trigeminal neuralgia is a neurological disease. It is often treated by puncturing the trigeminal nerve through the skin and the oval foramen of the skull to selectively destroy the pain nerve. The process of puncture operation is difficult because the morphology of the foramen ovale in the skull base is varied and the surrounding anatomical structure is complex. Computer-aided puncture guidance technology is extremely valuable for the treatment of trigeminal neuralgia. Computer-aided guidance can help doctors determine the puncture target by accurately locating the foramen ovale in the skull base. Foramen ovale segmentation is a prerequisite for locating but is a tedious and error-prone task if done manually. In this paper, we present an image segmentation solution based on the multiatlas method that automatically segments the foramen ovale. We developed a data set of 30 CT scans containing 20 foramen ovale atlas and 10 CT scans for testing. Our approach can perform foramen ovale segmentation in puncture operation scenarios based solely on limited data. We propose to utilize this method as an enabler in clinical work.

2019 ◽  
Vol 19 (2) ◽  
pp. E117-E121
Author(s):  
Bradley T Schmidt ◽  
Conrad D Pun ◽  
Wendell B Lake ◽  
Daniel K Resnick

Abstract Background Percutaneous glycerol rhizotomy (PGR) is a well-described treatment for trigeminal neuralgia; however, the technique in using surface landmarks and fluoroscopy has not drastically changed since being first introduced. In this paper, we describe a protocol for PGR using computed tomography (CT) guidance based on an experience of over 7 yr and 200 patients. Objective To introduce an approach for PGR using CT guidance and, in doing so, demonstrate possible benefits over the traditional fluoroscopic technique. Methods Using a standard CT scanner, patients are placed supine with head in extension. Barium paste and a CT scout image are used to identify and plan a trajectory to the foramen ovale. A laser localization system built into the CT scanner helps to guide placement of the spinal needle into the foramen ovale. The needle position in the foramen is confirmed with a short-sequence CT scan. Results CT-guided PGR provides multiple benefits over standard fluoroscopy, including improved visualization of the skull base and significant reduction in radiation exposure to the surgeon and staff. Side benefits include improved procedure efficiency, definitive imaging evidence of correct needle placement, and potentially increased patient safety. We have had no significant complications in over 200 patients. CONCLUSION CT-guided PGR is a useful technique for treating trigeminal neuralgia based on better imaging of the skull base, better efficiency of the procedure, and elimination of radiation exposure for the surgeon and staff compared to traditional fluoroscopic based techniques.


2020 ◽  
Vol 72 (1) ◽  
Author(s):  
Ryuho Kataoka

Abstract Statistical distributions are investigated for magnetic storms, sudden commencements (SCs), and substorms to identify the possible amplitude of the one in 100-year and 1000-year events from a limited data set of less than 100 years. The lists of magnetic storms and SCs are provided from Kakioka Magnetic Observatory, while the lists of substorms are obtained from SuperMAG. It is found that majorities of events essentially follow the log-normal distribution, as expected from the random output from a complex system. However, it is uncertain that large-amplitude events follow the same log-normal distributions, and rather follow the power-law distributions. Based on the statistical distributions, the probable amplitudes of the 100-year (1000-year) events can be estimated for magnetic storms, SCs, and substorms as approximately 750 nT (1100 nT), 230 nT (450 nT), and 5000 nT (6200 nT), respectively. The possible origin to cause the statistical distributions is also discussed, consulting the other space weather phenomena such as solar flares, coronal mass ejections, and solar energetic particles.


1974 ◽  
Vol 40 (2) ◽  
pp. 143-156 ◽  
Author(s):  
William H. Sweet ◽  
James G. Wepsic

✓ The authors report their experience in the treatment of trigeminal neuralgia with controlled increments of radiofrequency heating from an electrode placed in the Gasserian ganglion or its posterior rootlets. Touch is preserved in some or all of a trigeminal zone rendered analgesic. The electrode tip is introduced through the foramen ovale and placed among the desired rootlets with the help of a combination of radiographs and the conscious patient's response to electrical stimulation with a square wave signal and gentle electrical heating. The degree of heat is measured by a thermister at the electrode tip. The patient's cooperation is maintained by the use of the neurolept anesthetic Innovar and the production of brief unconsciousness for the painful parts of the operation by methohexital (Brevital). Of 274 patients with facial pain so treated, 214 had trigeminal neuralgia; 91% of the latter group experienced relief of pain and 125 followed for 2½ to 6 years had a recurrence rate of 22%. In a total of 353 procedures, there has been no mortality and no neurological morbidity outside the trigeminal nerve. Only six of the patients with trigeminal neuralgia have complained significantly of postoperative paresthesias. The most serious undesired result has been the production of an anesthetic cornea in 28 patients, one of whom lost the sight of one eye due to corneal scarring. Correlating findings in our patients with those in studies by other authors, we conclude that the preservation of some touch is due to resistance to heating by the heavily myelinated A-beta fibers.


2021 ◽  
Vol 70 (10) ◽  
Author(s):  
Kazuyoshi Gotoh ◽  
Makoto Miyoshi ◽  
I Putu Bayu Mayura ◽  
Koji Iio ◽  
Osamu Matsushita ◽  
...  

The options available for treating infections with carbapenemase-producing Enterobacteriaceae (CPE) are limited; with the increasing threat of these infections, new treatments are urgently needed. Biapenem (BIPM) is a carbapenem, and limited data confirming its in vitro killing effect against CPE are available. In this study, we examined the minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) of BIPM for 14 IMP-1-producing Enterobacteriaceae strains isolated from the Okayama region in Japan. The MICs against almost all the isolates were lower than 0.5 µg ml−1, indicating susceptibility to BIPM, while approximately half of the isolates were confirmed to be bacteriostatic to BIPM. However, initial killing to a 99.9 % reduction was observed in seven out of eight strains in a time–kill assay. Despite the small data set, we concluded that the in vitro efficacy of BIPM suggests that the drug could be a new therapeutic option against infection with IMP-producing CPE.


2021 ◽  
Author(s):  
Monique B. Sager ◽  
Aditya M. Kashyap ◽  
Mila Tamminga ◽  
Sadhana Ravoori ◽  
Christopher Callison-Burch ◽  
...  

BACKGROUND Reddit, the fifth most popular website in the United States, boasts a large and engaged user base on its dermatology forums where users crowdsource free medical opinions. Unfortunately, much of the advice provided is unvalidated and could lead to inappropriate care. Initial testing has shown that artificially intelligent bots can detect misinformation on Reddit forums and may be able to produce responses to posts containing misinformation. OBJECTIVE To analyze the ability of bots to find and respond to health misinformation on Reddit’s dermatology forums in a controlled test environment. METHODS Using natural language processing techniques, we trained bots to target misinformation using relevant keywords and to post pre-fabricated responses. By evaluating different model architectures across a held-out test set, we compared performances. RESULTS Our models yielded data test accuracies ranging from 95%-100%, with a BERT fine-tuned model resulting in the highest level of test accuracy. Bots were then able to post corrective pre-fabricated responses to misinformation. CONCLUSIONS Using a limited data set, bots had near-perfect ability to detect these examples of health misinformation within Reddit dermatology forums. Given that these bots can then post pre-fabricated responses, this technique may allow for interception of misinformation. Providing correct information, even instantly, however, does not mean users will be receptive or find such interventions persuasive. Further work should investigate this strategy’s effectiveness to inform future deployment of bots as a technique in combating health misinformation. CLINICALTRIAL N/A


Author(s):  
C. Guo ◽  
X. Liu ◽  
Y. Zhang ◽  
Z. Cai ◽  
Y. Guo ◽  
...  
Keyword(s):  

Diagnostics ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 73
Author(s):  
Seçil Aksoy ◽  
Arzu Sayın Şakul ◽  
Durmuş İlker Görür ◽  
Bayram Ufuk Şakul ◽  
Kaan Orhan

The study aimed to establish and evaluate anatomoradiological landmarks in trigeminal neuralgia patients using computed tomography (CT) and cone-beam CT. CT images of 40 trigeminal neuralgia (TN) and 40 healthy individuals were retrospectively analyzed and enrolled in the study. The width and length of the foramen rotundum (FR), foramen ovale (FO), foramen supraorbitale, and infraorbitale were measured. The distances between these foramen, between these foramen to the median plane, and between the superior orbital fissure, FO, and FR to clinoid processes were also measured bilaterally. Variations were evaluated according to groups. Significant differences were found for width and length of the foramen ovale, length of the foramen supraorbitale, and infraorbitale between TN and control subjects (p < 0.05). On both sides, FO gets narrower and the length of the infraorbital and supraorbital foramen shortens in the TN group. In most of the control patients, the plane which passes through the infraorbital and supraorbital foramen intersects with impression trigeminale; 70% on the right-side, and 67% in the left-side TN groups. This plane does not intersect with impression trigeminale and deviates in certain degrees. The determination of specific landmarks allows customization to individual patient anatomy and may help the surgeon achieve a more selective effect with a variety of percutaneous procedures in trigeminal neuralgia patients.


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