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Ketamine may be a novel pharmacologic approach to enhance resilience and protect against stress-related disorders, but the molecular targets underlying this response remain to be fully characterized. The multifunctional protein p11 is crucial in the pathophysiology of depression and antidepressant responses. However, it is still unclear whether p11 plays a role in the pro-resilience effects induced by ketamine. Here, we demonstrated that prophylactic administration of ketamine buffers passive stress-induced maladaptive phenotypes induced by chronic stress exposure. Spatial neurotransmitter and metabolite analysis revealed that prophylactic ketamine was also effective in blunting stress-induced disturbances of tryptophan metabolism in dorsal raphe nuclei (DRN). Additionally, we demonstrated that ketamine prevented chronic restraint stress-induced p11 reduction in DRN, a highly p11-enriched region. Furthermore, we provide novel evidence indicating that p11 deficiency regulates susceptibility to stress-induced depression-related phenotypes, and these behavioral maladaptations are dependent, at least in part, on p11 function in serotonergic neurons. Spatial neurotransmitter and metabolite analysis also showed a reduction of tryptophan and dopamine metabolism in DRN of serotonergic p11-deficient mice. Viral-mediated downregulation of p11 within DRN induced a stress-susceptible phenotype. Finally, our results also unveiled that the ability of ketamine to elicit a pro-resilience response against stress-induced maladaptive phenotypes was occluded when p11 was selectively deleted in serotonergic neurons. Altogether, we showed a previously unexplored role of the DRN circuit in regulating stress susceptibility and resilience-enhancing actions of ketamine., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

In this work we explored metabolic aspects of human primary leukemic lymphocytes that hold a potential impact on the treatment of Bruton tyrosine kinase (BTK)-driven diseases. Our results suggest that there is crosstalk between Bruton tyrosine kinase (BTK) signaling and bioenergetic stress responses. In primary chronic lymphocytic leukemia (CLL) lymphocytes, pharmacological interference with mitochondrial ATP synthesis or glucose metabolism affects BTK activity. Conversely, an inhibitor of BTK used clinically (ibrutinib) induces bioenergetic stress responses that in turn affect ibrutinib resistance. Although the detailed molecular mechanisms are still to be defined, our work shows for the first time that in primary B cells, metabolic stressors enhance BTK signaling and suggest that metabolic rewiring to hyperglycemia affects ibrutinib resistance in TP53 deficient chronic lymphocytic leukemia (CLL) lymphocytes.

Hemangiomas are tumors. Hemangiomas near the geniculate ganglion or in the internal acoustic meatus are well known but rare. We present two cases of hemangiomas located at the porus acusticus, an even more rare site. MRI showed a millimeter-sized tumor, located in the porus acusticus, developing perpendicular to the axis of the acoustico-facial nerves, surrounding them. They were hyperintense on T1-weighted images, strongly hyperintense on T2-weighted images with a characteristic progressive and marked enhancement after injection of gadolinium DTPA. Similar signal abnormalities were present in the adjacent temporal bone, and CT scan demonstrated a honeycomb appearance with intratumoral bony spicules. These imaging criteria allows differentiation between hemangioma and neurinoma. We hypothesize that this location is related to the presence of a rich vascular plexus of the dura mater in this area.

Enlargement of the pituitary gland is a frequent cause of incidentaloma and of referrals to endocrinologists for hormonal evaluation and therapeutic advice. In neuroradiological series, 25-50% of healthy women who are 18-35 yr old have a convex superior pituitary contour, but pituitary height exceeds 9 mm in less than 0.5% of cases. This study was performed to provide thorough clinical and hormonal data and long-term endocrinological and imaging follow-up data on subjects with incidentally discovered pituitary hypertrophy (height > 9 mm). Seven eugonadal nulliparous women, 15-27 yr old, referred between 1989 and 1998 with incidentally diagnosed pituitary gland enlargement (height > 9 mm) and a suspected pituitary tumor, were studied. At presentation and at yearly intervals, PRL plasma levels and corticotropic, somatotropic, and thyrotropic pituitary function were measured; and pituitary dimensions and signal on magnetic resonance imaging (MRI), before and after iv gadolinium-diethylene-triamine-pentaacetic acid injection, were assessed. PRL plasma levels were normal; and corticotropic, somatotropic, and thyrotropic pituitary function was considered normal in all cases. In all the women, the upper boundary of the pituitary was convex, on MRI, and touched the optic chiasm in four cases. The width and anteroposterior diameter of the gland were normal. The pituitary itself seemed normal, with a homogeneous signal, on plain and dynamic studies with iv contrast injection. Despite normal initial hormone values, two women underwent surgery, by the transsphenoidal approach, in another center. During surgery, the pituitary seemed normal in both cases, with no evidence of tumoral or inflammatory processes. Biopsy specimens showed the morphologic characteristics of a normal, nonhyperplastic pituitary gland. All seven women were seen at yearly intervals for 2-8 yr (median, 4 yr). Clinical and hormonal status remained stable, as did the structure and size of pituitary, on serial MRI. No tumor formation occurred, supporting the diagnosis of physiologic hypertrophy of the pituitary gland. In conclusion, these observations suggest that careful examination of MRI results may help to distinguish physiologic pituitary hypertrophy from pituitary tumors and infiltrating lesions. The former diagnosis is confirmed by normal baseline pituitary function in extensive hormonal tests. Correct identification of such patients is important to avoid unnecessary pituitary surgery and costly MRI surveillance.

Tumors of the cerebellopontine angle (CPA) are frequent; acoustic neuromas and meningiomas represent the great majority of such tumors. However, a large variety of unusual lesions can also be encountered in the CPA. The site of origin is the main factor in making a preoperative diagnosis for an unusual lesion of the CPA. In addition, it is essential to analyze attenuation at computed tomography (CT), signal intensity at magnetic resonance (MR) imaging, enhancement, shape and margins, extent, mass effect, and adjacent bone reaction. CPA masses can primarily arise from the cerebellopontine cistern and other CPA structures (arachnoid cyst, nonacoustic schwannoma, aneurysm, melanoma, miscellaneous meningeal lesions) or from embryologic remnants (epidermoid cyst, dermoid cyst, lipoma). Tumors can also invade the CPA by extension from the petrous bone or skull base (cholesterol granuloma, paraganglioma, chondromatous tumors, chordoma, endolymphatic sac tumor, pituitary adenoma, apex petrositis). Finally, CPA lesions can be secondary to an exophytic brainstem or ventricular tumor (glioma, choroid plexus papilloma, lymphoma, hemangioblastoma, ependymoma, medulloblastoma, dysembryoplastic neuroepithelial tumor). A close association between CT and MR imaging findings is very helpful in establishing the preoperative diagnosis for unusual lesions of the CPA.

The central canal of the spinal cord is present at birth and becomes progressively obliterated. Cadaver studies have shown that it may persist partially or completely. To our knowledge, this entity has not been described on MRI. We reviewed 794 MRI studies of the spinal cord, and found 12 patients (aged 14 to 65 years) who had an intramedullary cavity. The cavity was at the junction of the ventral 1/3 and dorsal 2/3 of the spinal cord, except at the level of the lumbar enlargement, where it was central. It was filiform in most cases, although sometimes fusiform (3 to 4 mm in diameter), and had regular contours. The cavity were thoracic in 69 % of cases. The clinical features were totally unrelated to the image, and there were no anatomical factors (Chiari malformation, dysraphism) predisposing to syringomyelia. The images were perfectly compatible with a persistent central canal, which we interpret as a variant of normal anatomy. Therefore it is important to regard these findings as normal, to avoid unnecessary treatment and follow-up.

Summary: A stereotactic approach to the pons through the middle cerebellar peduncle based on MR studies was used to biopsy 18 patients. The stereotactic coordinates and angles were defined with reference to three orthogonal planes (midsagittal, IVth ventricular floor and pontomedullary junction). The pathological diagnoses were in keeping with clinical outcome and comprised five highgrade astrocytomas, three low-grade astrocytomas, two glioblastomas multiforme, two oligodendrogliomas, two primitive neuroectodermic tumours, two lymphomas, one medulloblastoma, and one tuberculosis. This approach provides a high yield of positive histological diagnoses with little morbidity (transient neurological deficits in two cases) and thereby avoids inappropriate therapy.

An 8-year-old child was examined because of conductive hearing loss with a retrotympanic mass on otoscopy. CT and MR angiography showed a large inferior tympanic artery traversing the hypotympanum and joining a thin, irregular internal carotid artery with a normal middle meningeal artery. These investigations, coupled with knowledge of the embryological development allowed a diagnosis of a complex vascular anomaly in the middle ear and avoided potential surgical complications.

We present a case of osteoid osteoma of the petrous bone presenting with progressive sensorineural hearing loss. CT showed a dense homogeneous mass at the promontory surrounded by a thin bony border. On MRI this lesion gave intermediate signal intensity on T1- and T2-weighted spin-echo images and enhanced intensely with gadolinium. Surgical removal and pathological study proved the diagnosis.

We reviewed 11 cases of intramedullary cavernous haemangiomas (IMCH) studied by MRI, to assess its diagnostic value in these lesions. Follow-up MRI was obtained in five patients 7 days-2 years following the initial study. In one case a postoperative examination was obtained. The diagnosis was pathologically proven in ten cases, and supported in the last by a family and personal history of cavernous haemangiomas. A reticulate appearance with areas of mixed signal intensity in both T1- and T2-weighted images was the most common finding. Homogeneous high, low or intermediate signal intensity was each found in one case. Two small lesions gave low signal. A rim of low signal was less common than in cerebral cavernous haemangiomas. In one case, the brain showed more than 20 lesions with the MRI appearances of cavernous haemangiomas. In two of five patients, serial preoperative MRI showed progressive disappearance of high-signal areas on both T1- and T2-weighted images. To find a haemorrhagic intramedullary lesion on MRI is not rare. Although the appearances are not pathognomonic, an IMCH can be suggested. We suggest that the following characteristics may help: (1) a personal and/or family history of cavernous haemangiomas; (2) typical MRI appearances of mixed acute, subacute and chronic haemorrhage; (3) a tendency for signal intensity to decrease on follow-up; (4) normal spinal angiography; and (5) associated brain lesions.

Objective: Our goal was to assess medullary lesions in patients suffering from chronic progressive radiation myelopathy (CPRM) using MRI., Materials and Methods: In a group of 10 patients suffering from CPRM, MRI findings (11 examinations), radiation protocols, and patient prognoses were reviewed., Results: A cord enlargement was demonstrated in five cases, whereas four cases presented with medullary atrophy. As demonstrated by MRI, radiation-induced medullary lesions progressed toward cord atrophy in one patient. When MRI and/or comparison myelogram were performed within 8 months following the onset of the myelopathy, a cord enlargement was usually encountered. When the patient was evaluated > 8 months after the first neurological symptoms, a cord atrophy was always demonstrated. Medullary lesions extended beyond the boundaries of the radiation field in 67% of the cases. However, with the exception of one case, the main focus of the cord damage was included within an irradiated cord segment. An enlarged cord was often associated with a neurologic deterioration and a fatal outcome. In patients with cord atrophy, the neurologic deficit was often static and survival rates were better., Conclusion: These results suggest a revision of classic criteria used for the diagnosis of CPRM. By demonstrating cord lesions, MRI helps to establish disease prognosis.

Confusion developed in a 44-year-old man, who had diarrhoea and weight loss for three months. Jejunal biopsy showed infiltration by PAS-positive macrophages, indicating Whipple's disease. Cranial MRI disclosed multiple lesions mainly in the white matter and grey-white matter junction better demonstrated after gadolinium injection.

Two cases of central nervous system Behçet's disease, studied by gadolinium-enhanced MRI, are presented. In one patient, whose clinical picture was dominated by a brain syndrome, the gadolinium enhancement resolved with clinical improvement, although the hyperintense areas in the mesencephalon on T2-weighted images persisted. In the second, who had a pseudobulbar palsy and a mild right hemiparesis, there were many abnormal areas, but an enhancing focus in the posterior limb of the left internal capsule was probably the lesion responsible for the hemiparesis.

A retrospective analysis of the MR findings in 92 cases of acoustic neuromas is presented. The method of examination included in all cases intravenous injection of Gadolinium (Gd-DTPA or DOTA) with realization of sections in the axial and coronal planes. In 21 cases native MR studies were performed in the axial plane, before Gadolinium injection, with T1WI (n = 21), and T2WI (n = 6) images. Tumors were strictly intracanalar in 19 cases (20.7%), only localized in the cerebellopontine angle (CPA) in 5 cases (5.4%), and in 68 cases (73.9%) the tumors had intra- and extracanalar components. In this last group of lesions, 63.2% completely filled the internal auditory canal (IAC), and 36.8% occupied the internal portion of the IAC. In most cases (85.3%) the mean diameter of the CPA component was less than or equal to 2.5 cm. Lesions were more frequently homogeneous (58.8%) after Gd i.v.-enhancement. Heterogeneity was noted mainly in large lesions (greater than 2.5 cm: 100%). In all cases but one, the tumors were round, or oval-shaped, well-delineated, and did not present significant contact with the petrous bone. In 80.9% of CPA lesions, the center of the tumor was posteriorly excentered in relation to the internal auditory canal, whereas it was centered in 16.2% of cases. Widening of the IAC was observed in 51.1% of cases. In 45.2% of tumors of the CPA, smoothing of the posterior edge of the porus was visible.

MR findings in four patients with MR evidence of congenital cystic dilatation of the ventriculus terminalis were reviewed retrospectively. The ventriculus terminalis is a small cavity of the conus medullaris that forms during embryonic development as result of canalization and retrogressive differentiation. The dilated ventriculus terminalis appears on MR images as a small ovoid cavity with regular margination; intralesional fluid resembles cerebrospinal fluid on all MR sequences. After injection of contrast material, MR imaging shows no enhancement of the cyst or its wall, and thus differentiates congenital dilatation of the ventriculus terminalis from cystic tumors, which occur more frequently in this region.

Hypopituitarism and diabetes insipidus are often idiopathic conditions. A retrospective study of 6 cases of diabetes insipidus and 8 cases of partial or global idiopathic anterior hypopituitarism has shown that MRI is of considerable value to detect abnormalities of the pituitary stalk or hypothalamo-pituitary "relay". On the basis of MRI findings, some cases of idiopathic hypopituitarism can now be grouped together in a new entity which may be called hypopituitarism due to neonatal transection of the pituitary stalk.

The clinical and magnetic resonance (MR) imaging findings in 20 patients with MR evidence of occult cerebrovascular malformations (OCVMs) were retrospectively analyzed. Of 27 lesions followed up throughout a mean period of 18 months, eight showed obvious evolution on MR images (four cases of regression and four cases of new bleeding). Three new independent lesions were disclosed. Clinical evolution was discordant with MR findings in five patients. In the other patients, topography of the lesion, mass effect, and location of the hemorrhage could explain clinical data. The dynamic nature of OCVMs must be considered in decisions on therapeutic management.

A case of cystic schwannoma that presented as an intraaxial lesion on CT is reported. Magnetic resonance was able to detect the extraaxial origin of the tumor.

In order to assess the value of MRI in the depiction of intracranial nerves, we retrospectively reviewed 60 patients investigated over a 2-year period. The purposes of this study were: 1) to determine the score of MRI in detecting cranial nerves III to XII, and 2) to establish accurate landmarks for easy detection of these nerves. Cranial nerves III, V, VII and VIII are well seen (70 to 100%), very often on axial, sagittal and coronal sections. Nerves IX to XII are correctly studied only on axial planes (81 and 83%), but it is difficult to distinguish between the vagus nerve and the glossopharyngeal and spinal nerves. Due to their oblique direction and small size, nerves IV and VI are seldom visualized. The most important landmarks are the chiasma, the colliculi, Meckel's cavity, the internal auditory canal, the jugular foramen, the hypoglossal canal and the brainstem structures. We suggest the following scanning technique: short spin-echo sequences (TR 600 ms, TE 20 ms), 3 to 5 mm thick contiguous sections, 16 to 20 cm field of view with 4 or 2 excitations respectively, 256 x 256 matrix, and at least one acquisition plane (axial plane), but preferably two or three planes. MRI is a sensitive examination in the recognition of cranial nerves. It should be the first-step exploratory procedure in patients with cranial nerve pathology.

The functional anatomy of the facial artery consists of a group of constant arterial pedicles nourishing a specific territory and supplied by a variable facial trunk. There is a hemodynamic balance with other variable connecting trunks such as the transverse facial and internal maxillary arteries. Every type of variant, irrespective of its origin, may be understood based on the constant relationships and anastomoses involved. Knowledge of this functional anatomical system is crucial to an understanding of the blood supply to the face.

Twenty cases of intrapetrous lesions were studied by a 1.5 T magnetic resonance (MR) unit. In all cases, comparisons were made between MR, CT and clinical findings. Our present material included 9 cholesteatomas, 1 cholesterol cyst, 3 primary epidermoid carcinomas, 2 metastatic neoplasms, 1 glomus jugulare tumor and 4 facial neurinomas. Gadolinium was injected in 7 cases and seemed to be the best method for studying the intrapetrous tumors. MR permitted accurate topographic study and assessment of tumoral extension, as well as a ready demonstration of tumor vascularity. The present findings also showed that MR is not capable of defining small bony detail or calcifications.

Portal vein and its two branches were evaluated by ultrasound in 12 children (14 months to eight years) with portal cavernomas; the cavernomas appeared idiopathic (five cases) or were secondary either to a catherization of umbilical vein in the neonatal period (six cases) or to trauma (one case). Angiographic confirmation of cavernoma was obtained in all patients. Twelve patients with intrahepatic portal hypertension were used as controls. The following abnormal patterns were observed: (1) absence of normal portal vein; (2) absence of normal portal division; (3) tortuous, small and irregular appearance and/or abnormal sagittal division of the venous system; (4) presence of small linear echoes dotting the portal vein; (5) presence of small linear echoes dotting the porta hepatis area. Ultrasonogram was normal in the 12 controls. Thus, ultrasound appears to be a procedure of choice in the evaluation of portal cavernomas, permitting postponement of invasive angiographic examination until surgical treatment is anticipated.

Thirteen patients with craniopharyngioma were explored with a 1.5 Tesla magnetic resonance imager. The results were compared with those of CT and with operative findings. The MRI signals were correlated with the biochemical composition of the cysts (proteins, lipids, iron, LDH) in 5 cases; 2 patients were studied after an intravenous injection of gadolinium DOTA. MRI proved vastly superior to CT to evaluate the spread and identify the various components of craniopharyngiomas (cysts, fleshy parts, haemorrhages), except for calcifications. Gadolinium improved the detection of fleshy parts and "active" cysts. The signals emitted by cysts were extremely variable on T1-weighted sequences. The correlation between MRI and biochemical data was complex, but it appeared that protein, lipid and iron concentrations had a major influence on cyst signals. MRI with gadolinium may be envisaged as first-line examination to improve the evaluation of spread, determine the prognosis and detect recurrences of craniopharyngiomas. CT could be reserved to difficult cases with invasion of bones and sinuses.

The authors have reviewed the experimental literature about the different agents used for endovascular embolization: clots, tissues, duramater, Gelfoam, oxydized cellulose, Ivalon, beads, microspheres, cyanoacrylates, silicone, barium. Each occlusive agent was studied in regard to its physical properties, injection methods, characteristics of obstruction, vascular reaction, and toxicity. The level and quality of obstruction obtained depend on many factors which are discussed.

A bipolar electrode for transcatheter electrocoagulation with alternating current is described. This electrode avoids the problem of variation of the electric impedance of the monopolar electrode/ground plate system. It allows quick, safe, and reliable endovascular occlusion of vessels.

Four patients (aged 5, 8, 14, and 51 years at initial manifestation) with isolated eosinophilic granulomas of the orbital frontal bone displayed short symptomatic periods (two weeks to three months) and some combination of erythema of the lids, a soft, palpable anterior orbital mass, periorbital pain, and osteolytic bone lesions on roentgenography. The bone lesions roentgenographically exhibited irregular, serrated, and sclerotic margins, distinguishing them from the more oval appearance of dermoid cysts. Electron microscopy performed in one case disclosed the presence of Langerhans' granules in the cytoplasm of the histiocytes, indicating that the orbital disease is a mild form of "histiocytosis X" and a benign proliferation of a specific kind of histiocyte--the Langerhans' cell. On follow-up (two to 20 years), after incomplete curettage of two lesions coupled with low doses of postoperative radiotherapy, there was reconstitution of the bone defects, whereas more extensive surgery performed on the other two patients resulted in permanent but subclinical bone defects.

Ten cases of painful ophthalmoplegia are reported. In all cases pain marked the onset of the disease; the condition was mostly unilateral. Recurrence and dramatic response to steroid therapy were more constant features than angiographic findings which may be completely normal. CAT permitted us to eliminate a tumor of the cavernous sinus in 7 cases, but in one case, which was operated, an aggravation followed surgery. Despite complete investigations of all patients, some questions remain unanswered. Is it an inflammatory or an allergic inflammatory process? (And the presence of antinuclear factor in an only case does not permit it to respond.) Why is the process confined to the superior orbital fissure? Mathew and Chandy tried to find a similarity between this syndrome and Bell's palsy although the 2 syndromes have not been shown to coexist. Is the Tolosa-Hunt syndrome comparable to the pseudotumor of the orbit? Although the dura mater is inserted on the border of the sphenoidal cleft, some patients may altern the 2 syndromes.

A comparison has been carried out of results of cerebral and spinal-cord angiography with two non-ionic contrast media, iohexol and Iopamiron, and a low-osmolality contrast medium, Hexabrix. A comparative study of iohexol, Hexabrix, and Iopamiron was carried out in a first group of 41 patients, and Hexabrix was compared with Iopamiron in a second group of 56. Evaluation criteria included local and general safety, as well as quality of angioscopy and angiography. In the first group of patients there were no significant differences in safety between the three agents. On the other hand, quality of visualisation during angioscopy with Hexabrix was clearly better. In the second group, safety and quality of the radiographic images were identical; however, once again, quality of angioscopy was better with Hexabrix than with Iopamiron. We conclude that Hexabrix appears to be the best opacifying agent currently available for cerebral and spinal-cord angiography. While results with Iopamiron were quite similar, the latter agent is slightly more expensive.

The successful treatment of a congenital vertebral fistula with the balloon catheter occlusion technique is reported. A new approach is presented (the occipital approach), based upon the pathological enlargement of the second intervertebral space anastomosis between occipital and vertebral arteries.

Two successive hepatic arterial embolizations were performed in a patient with hypercalcemia secondary to hepatocellular carcinoma. The first procedure was performed on an emergency basis due to a cardiovascular episode and was immediately beneficial. The second procedure, performed five months later for a recurrence, was effective in 3 days; 13 months later, there had been no recurrence.

The principles underlying the use of embolisation in the management of tumours and vascular malformations of the head and neck are reviewed. The percutaneous angiographic technique is employed to embolise the lesion, producing the effects of haemostasis, reduction of tissue mass and relief of pain. Specific clinical applications are discussed with illustrative examples.

We report the magnetic resonance findings in a case of post-traumatic diabetes insipidus (DI). They consisted of pituitary stalk rupture shown on both coronal and sagittal planes with associated disappearance of the normal high signal intensity of the posterior lobe on T1 images. This last sign, previously described in nontraumatic DI, appears to represent a finding indicating nonfunctioning neurohypophysis.