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Neuroradiology Nov 2023While MRI has become the imaging modality of choice in the diagnosis of sellar tumors, no systematic attempt has yet been made to align radiological reporting of...
PURPOSE
While MRI has become the imaging modality of choice in the diagnosis of sellar tumors, no systematic attempt has yet been made to align radiological reporting of findings with the information needed by the various medical disciplines dealing with these patients. Therefore, we aimed to determine the prevailing preferences in this regard through a nationwide expert survey.
METHODS
First, an interdisciplinary literature-based catalog of potential reporting elements for sellar tumor MRI examinations was created. Subsequently, a web-based survey regarding the clinical relevance of these items was conducted among board certified members of the German Society of Neurosurgery, German Society of Radiation Oncology, and the Pituitary Working Group of the German Society of Endocrinology.
RESULTS
A total of 95 experts (40 neurosurgeons, 28 radiation oncologists, and 27 endocrinologists) completed the survey. The description of the exact tumor location, size, and involvement of the anatomic structures adjacent to the sella turcica (optic chiasm, cavernous sinus, and skull base), occlusive hydrocephalus, relationship to the pituitary gland and infundibulum, and certain structural characteristics of the mass (cyst formation, hemorrhage, and necrosis) was rated most important (> 75% agreement). In contrast, the characterization of anatomic features of the nasal cavity and sphenoid sinus as well as the findings of advanced MRI techniques (e.g., perfusion and diffusion imaging) was considered relevant by less than 50% of respondents.
CONCLUSION
To optimally address the information needs of the interdisciplinary treatment team, MRI reports of sellar masses should primarily focus on the accurate description of tumor location, size, internal structure, and involvement of adjacent anatomic compartments.
PubMed: 37735221
DOI: 10.1007/s00234-023-03222-w -
International Journal of Ophthalmology 2023To describe the clinical and radiologic features of retrolaminar migration silicone oil (SiO) and observe the dynamic position of ventricular oil accumulation in supine...
AIM
To describe the clinical and radiologic features of retrolaminar migration silicone oil (SiO) and observe the dynamic position of ventricular oil accumulation in supine and prone.
METHODS
For this retrospective study, 29 patients who had a history of SiO injection treatment and underwent unenhanced head computed tomography (CT) were included from January 2019 to October 2022. The patients were divided into migration-positive and negative groups. Clinical history and CT features were compared using Whitney and Fisher's exact tests. The dynamic position of SiO was observed within the ventricular system in supine and prone. CT images were visually assessed for SiO migration along the retrolaminar involving pathways for vision (optic nerve, chiasm, and tract) and ventricular system.
RESULTS
Intraocular SiO migration was found in 5 of the 29 patients (17.24%), with SiO at the optic nerve head (=1), optic nerve (=4), optic chiasm (=1), optic tract (=1), and within lateral ventricles (=1). The time interval between SiO injection and CT examination of migration-positive cases was significantly higher than that of migration-negative patients (22.8±16.5mo 13.1±2.6mo, <0.001). The hyperdense lesion located in the frontal horns of the right lateral ventricle migrated to the fourth ventricle when changing the position from supine to prone.
CONCLUSION
Although SiO retrolaminar migration is unusual, the clinician and radiologist should be aware of migration routes. The supine combined with prone examination is the first-choice method to confirm the presence of SiO in the ventricular system.
PubMed: 37724262
DOI: 10.18240/ijo.2023.09.20 -
Chinese Clinical Oncology Aug 2023Radiation is integral to the treatment of glioblastoma (GBM). However, radiation-induced scalp toxicity can negatively impact patients' quality of life. Volumetric...
BACKGROUND
Radiation is integral to the treatment of glioblastoma (GBM). However, radiation-induced scalp toxicity can negatively impact patients' quality of life. Volumetric modulated arc therapy (VMAT) optimizes the dose to organs at risk (OARs). We hypothesize that a scalp-sparing VMAT (SSV) approach can significantly reduce undesirable doses to the scalp without compromising the target dose.
METHODS
This is a retrospective cross-sectional study of GBM patients who originally received radiation with non-SSV. We contoured the scalp as a 5 mm rind-like structure beneath the skin above the level of the foramen magnum. We replanned our patients using SSV techniques. We compared dosimetric data for the scalp, planning target volume (PTV), and select critical normal structures between non-SSV and SSV plans.
RESULTS
Nineteen patients with newly diagnosed GBMs were included in our study. All patients received 60 Gy in 30 fractions. 9 patients received it in a single course. The rest received 46 Gy in 23 fractions to an initial volume followed by 14 Gy in 7 fractions to a cone-down volume (split course). New VMAT plans were generated after adding the scalp as an OAR. The median scalp volume was 416 cm3 (363-468 cm3). The median reductions in scalp Dmin, Dmax, and Dmean were 43.5% (-100% to 0%), 2.8% (+13.4% to -24.9%), and 15.7% (+2.1% to -39.9%) respectively. Median reductions in scalp D20cc and D30 cc were 19.5% (-2.7% to -54.5%), and 19.0% (-5.3% to -39.5%) respectively. The median volumes of the scalp receiving 30 Gy, 40 Gy, and 50 Gy were reduced by 42.3% (-70.6% to -12.5%), 72% (-100% to -2.3%), and 92.4% (-100% to +5.4%) respectively. There were no significant differences in the doses delivered to the PTV, brainstem, optic nerves, and optic chiasm between SSV and non-SSV plans.
CONCLUSIONS
SSV can significantly reduce scalp radiation dose without compromising target coverage or critical normal structure doses. This may translate into reduced acute and late radiation toxicity to the scalp. A prospective trial evaluating the clinical benefits of SSV is ongoing (NCT03251027).
Topics: Humans; Cross-Sectional Studies; Glioblastoma; Prospective Studies; Quality of Life; Radiation Dosage; Radiotherapy, Intensity-Modulated; Retrospective Studies; Scalp; Clinical Trials as Topic
PubMed: 37699601
DOI: 10.21037/cco-23-15 -
Frontiers in Neuroscience 2023The effective transverse relaxation rate (R*) is sensitive to the microstructure of the human brain like the g-ratio which characterises the relative myelination of...
The effective transverse relaxation rate (R*) is sensitive to the microstructure of the human brain like the g-ratio which characterises the relative myelination of axons. However, the fibre-orientation dependence of R* degrades its reproducibility and any microstructural derivative measure. To estimate its orientation-independent part (R*) from single multi-echo gradient-recalled-echo (meGRE) measurements at arbitrary orientations, a second-order polynomial in time model (hereafter M2) can be used. Its linear time-dependent parameter, , can be biophysically related to R* when neglecting the myelin water (MW) signal in the hollow cylinder fibre model (HCFM). Here, we examined the performance of M2 using experimental and simulated data with variable g-ratio and fibre dispersion. We found that the fitted can estimate R* using meGRE with long maximum-echo time (TE ≈ 54 ms), but not accurately captures its microscopic dependence on the g-ratio (error 84%). We proposed a new heuristic expression for that reduced the error to 12% for compartmental R values. Using the new expression, we could estimate an MW fraction of 0.14 for fibres with negligible dispersion in a fixed human optic chiasm for the compartmental R values but not for the values. M2 and the HCFM-based simulations failed to explain the measured R*-orientation-dependence around the magic angle for a typical meGRE protocol (with TE ≈ 18 ms). In conclusion, further validation and the development of movement-robust meGRE protocols with TE ≈ 54 ms are required before M2 can be used to estimate R* in subjects.
PubMed: 37694109
DOI: 10.3389/fnins.2023.1133086 -
Brain Communications 2023Achiasmia is a rare visual pathway maldevelopment with reduced decussation of the axons in the optic chiasm. Our aim was to investigate clinical characteristics,...
Achiasmia is a rare visual pathway maldevelopment with reduced decussation of the axons in the optic chiasm. Our aim was to investigate clinical characteristics, macular, optic nerve and brain morphology in achiasmia. A prospective, cross-sectional, observational study of 12 participants with achiasmia [8 males and 4 females; 29.6 ± 18.4 years (mean ± standard deviation)] and 24 gender-, age-, ethnicity- and refraction-matched healthy controls was done. Full ophthalmology assessment, eye movement recording, a high-resolution spectral-domain optical coherence tomography of the macular and optic disc, five-channel visual-evoked responses, eye movement recordings and MRI scans of the brain and orbits were acquired. Achiasmia was confirmed in all 12 clinical participants by visual-evoked responses. Visual acuity in this group was 0.63 ± 0.19 and 0.53 ± 0.19 for the right and left eyes, respectively; most participants had mild refractive errors. All participants with achiasmia had see-saw nystagmus and no measurable stereo vision. Strabismus and abnormal head position were noted in 58% of participants. Optical coherence tomography showed optic nerve hypoplasia with associated foveal hypoplasia in four participants. In the remaining achiasmia participants, macular changes with significantly thinner paracentral inner segment ( = 0.002), wider pit ( = 0.04) and visual flattening of the ellipsoid line were found. MRI demonstrated chiasmatic aplasia in 3/12 (25%), chiasmatic hypoplasia in 7/12 (58%) and a subjectively normal chiasm in 2/12 (17%). Septo-optic dysplasia and severe bilateral optic nerve hypoplasia were found in three patients with chiasmic aplasia/hypoplasia on MRI. In this largest series of achiasmia patients to date, we found for the first time that neuronal abnormalities occur already at the retinal level. Foveal changes, optic nerve hypoplasia and the midline brain anomaly suggest that these abnormalities could be part of the same spectrum, with different manifestations of events during foetal development occurring with varying severity.
PubMed: 37680693
DOI: 10.1093/braincomms/fcad219 -
Cureus Aug 2023Non-functioning pituitary adenomas (NFPAs) are rare in females of reproductive age. We present the case of a 37-year-old pregnant woman in her second trimester with a...
Non-functioning pituitary adenomas (NFPAs) are rare in females of reproductive age. We present the case of a 37-year-old pregnant woman in her second trimester with a diagnosis of symptomatic pituitary macroadenoma with twin pregnancy. Magnetic resonance imaging (MRI) confirmed a well-defined macroadenoma compressing the optic chiasm, thus necessitating surgery. The patient underwent transnasal transsphenoidal resection of the tumor under general anesthesia. Anesthesia management posed challenges due to concurrent considerations of pregnancy and neurosurgery. Induction, maintenance, monitoring, and fluid management were carefully performed. The patient experienced a transient decrease in oxygen saturation, which improved with lung recruitment maneuvers. The surgery was successful without any complications. Postoperatively, an ophthalmology consultation was done, which showed an improvement in the patient's vision, as evidenced by the perimetry findings. Later, she delivered healthy twins at 36 weeks and six days of gestation. This case highlights the importance of a multidisciplinary approach and meticulous anesthetic management when dealing with pregnant patients undergoing non-obstetric surgery, ensuring optimal maternal-fetal perfusion and minimizing risks to both the mother and the fetus.
PubMed: 37664278
DOI: 10.7759/cureus.42891 -
Journal of Cerebrovascular and... Dec 2023Bilateral posterior communicating (pComm) artery aneurysms represent only 2% of mirror intracranial aneurysms. Usually, these are surgically approached through bilateral...
Bilateral posterior communicating (pComm) artery aneurysms represent only 2% of mirror intracranial aneurysms. Usually, these are surgically approached through bilateral craniotomies for clipping. We present the case of a 50-year-old female presenting with headache and horizontal diplopia. Neurological examination revealed a left oculomotor palsy, with no other neurological deficits. Imaging studies revealed bilateral aneurysmatic lesions in both internal carotid arteries (ICA). A conventional left pterional approach was planned in order to treat the symptomatic aneurysm, and, if deemed feasible, a contralateral clipping through the same approach. The procedure was performed in a hybrid operating room (HOR), performing an intraoperative digital subtraction angiography (DSA) and roadmapping assistance during dissection and clipping. Transoperatively, a post-fixed optic chiasm was identified, with a wide interoptic space, which allowed us to perform the contralateral clipping through a unilateral approach. This technique for clipping bilateral pComm aneurysms can be performed when the proper anatomical features are met.
PubMed: 37661758
DOI: 10.7461/jcen.2023.E2022.12.002 -
Scientific Reports Sep 2023We assessed the potential retinal microcirculation alterations for postoperative visual recovery in sellar/paraseller tumor patients with Optical Coherence Tomography...
We assessed the potential retinal microcirculation alterations for postoperative visual recovery in sellar/paraseller tumor patients with Optical Coherence Tomography Angiography (OCT-A). Two hundred ten eyes with sellar/parasellar tumor for which preoperative and postoperative (3 months) MRI Scans, Visual Acuity Test, Optical Coherence Tomography (OCT), OCT-A and, Visual Field Test data were available, besides 92 healthy eyes were evaluated. In the preoperative phase, significant reductions were observed in retinal vascular densities in various regions, including the Superficial Retinal Capillary Plexus (SRCP) (whole: p < 0.001, fovea: p = 0.025, parafovea: p < 0.001), Deep Retinal Capillary Plexus (DRCP) (whole: p < 0.001, fovea: p = 0.003, parafovea: p < 0.001), Peripapillary Vascular Density (PVD) (whole: p = 0.045, peripapillary: p < 0.001, nasal: p < 0.001, inferior: p < 0.001, temporal: p < 0.001), and Retinal Nerve Fiber Layer (RNFL) (nasal: p = 0.024, inferior: p < 0.001, temporal: p < 0.001, superior: p < 0.001) compared to the healthy control group. After surgery, the postoperative data of patients without chiasmal distortion were compared to their preoperative data. In the postoperative evaluation, significant increases were observed in vascular densities in patients without chiasmal distortion in the SRCP (whole: p < 0.001, parafovea: p = 0.045), DRCP (whole: p = 0.007, fovea: p = 0.006, parafovea: p = 0.040), PVD (peripapillary: p = 0.010, inferior: p < 0.001, temporal: p < 0.001, superior: p < 0.001), and RNFL (nasal: p = 0.011, inferior: p = 0.034, temporal: p = 0.046, superior: p = 0.011). Furthermore, significant associations were observed in the ROC analysis between the postoperative Visual Field Mean Deviation (VFMD) and SRCP (whole AUC = 0.793, p < 0.001, cut-off = 51.45, parafovea AUC = 0.820, p < 0.001, cut-off = 53.95), DRCP (whole AUC = 0.818, p < 0.001, cut-off = 55.95, parafovea AUC = 0.820, p < 0.001, cut-off = 59.05), PVD (temporal AUC = 0.692, p < 0.001, cut-off = 55.10), and RNFL (whole AUC = 0.690, p = 0.001, cut-off = 119.5, inferior AUC = 0.712, p < 0.001, cut-off = 144.75). These findings indicate a potential role of pre and post-operative OCT-A measurements in the assessment of surgical timing and postoperative visual recovery in patients with or without optic chiasm distortion.
Topics: Humans; Tomography, Optical Coherence; Decompression, Surgical; Lumbar Vertebrae; Angiography; Retina; Neoplasms
PubMed: 37658097
DOI: 10.1038/s41598-023-40956-2 -
NeuroImage. Clinical 2023The anterior optic pathway (AOP) is a system of three structures (optic nerves, optic chiasma, and optic tracts) that convey visual stimuli from the retina to the... (Review)
Review
The anterior optic pathway (AOP) is a system of three structures (optic nerves, optic chiasma, and optic tracts) that convey visual stimuli from the retina to the lateral geniculate nuclei. A successful reconstruction of the AOP using tractography could be helpful in several clinical scenarios, from presurgical planning and neuronavigation of sellar and parasellar surgery to monitoring the stage of fiber degeneration both in acute (e.g., traumatic optic neuropathy) or chronic conditions that affect AOP structures (e.g., amblyopia, glaucoma, demyelinating disorders or genetic optic nerve atrophies). However, its peculiar anatomy and course, as well as its surroundings, pose a serious challenge to obtaining successful tractographic reconstructions. Several AOP tractography strategies have been adopted but no standard procedure has been agreed upon. We performed a systematic review of the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) 2020 guidelines in order to find the combinations of acquisition and reconstruction parameters that have been performed previously and have provided the highest rate of successful reconstruction of the AOP, in order to promote their routine implementation in clinical practice. For this purpose, we reviewed data regarding how the process of anatomical validation of the tractographies was performed. The Cochrane Handbook for Systematic Reviews of Interventions was used to assess the risk of bias and thus the study quality We identified thirty-nine studies that met our inclusion criteria, and only five were considered at low risk of bias and achieved over 80% of successful reconstructions. We found a high degree of heterogeneity in the acquisition and analysis parameters used to perform AOP tractography and different combinations of them can achieve satisfactory levels of anterior optic tractographic reconstruction both in real-life research and clinical scenarios. One thousand s/mm was the most frequently used b value, while both deterministic and probabilistic tractography algorithms performed morphological reconstruction of the tract satisfactorily, although probabilistic algorithms estimated a more realistic percentage of crossing fibers (45.6%) in healthy subjects. A wide heterogeneity was also found regarding the method used to assess the anatomical fidelity of the AOP reconstructions. Three main strategies can be found: direct visual direct visual assessment of the tractography superimposed to a conventional MR image, surgical evaluation, and computational methods. Because the latter is less dependent on a priori knowledge of the anatomy by the operator, computational methods of validation of the anatomy should be considered whenever possible.
Topics: Humans; Diffusion Magnetic Resonance Imaging; Magnetic Resonance Imaging; Diffusion Tensor Imaging; Retina; Amblyopia
PubMed: 37651845
DOI: 10.1016/j.nicl.2023.103494