Pituitary neuroendocrine tumors, formerly referred to as pituitary adenomas, are common intracranial neoplasms. Most are benign and slow-growing. Clinical manifestations typically arise from hormonal hypersecretion or mass effect on adjacent structures. Hyponatremia due to syndrome of inappropriate antidiuretic hormone secretion is an uncommon presentation of pituitary tumors and has been rarely reported. We present the case of a 35-year-old woman with a history of secondary amenorrhea and infertility who exhibited progressive headache and recurrent presyncope episodes. Laboratory tests showed that the patient had severe hyponatremia (sodium {Na}: 121 mmol/L), low serum osmolality (252 mOsm/kg), inappropriately elevated urine osmolality (748 mOsm/kg), elevated urinary sodium (112 mEq/L), hypouricemia (1.9 mg/dL), and a fractional excretion of uric acid of 11.66%, consistent with syndrome of inappropriate antidiuretic hormone secretion. Hormonal assessment indicated hypogonadotropic hypogonadism characterized by diminished levels of follicle-stimulating hormone, luteinizing hormone, and estradiol. Magnetic resonance imaging of the brain showed a sellar mass measuring 19 × 31 × 32 mm with a suprasellar extension and compression of the optic chiasm. Visual field testing corroborated bitemporal hemianopsia. The patient had an endoscopic transsphenoidal resection of the lesion. Histopathological examination identified a plurihormonal mature pituitary neuroendocrine tumor of gonadotroph lineage, exhibiting positive immunohistochemical staining for SF-1 and INSM1, negative expression for Pit-1, and a Ki-67 proliferation index of 10%. This case illustrates an uncommon manifestation of a gonadotroph pituitary neuroendocrine tumor presenting as severe hyponatremia secondary to syndrome of inappropriate antidiuretic hormone secretion. Identifying this unusual presentation is crucial, as prompt diagnosis and intervention may avert considerable neurological, metabolic, and visual complications.

Rathke's cleft cysts are benign epithelial-lined sellar and suprasellar lesions that are often incidental findings but can cause visual deficits, hypopituitarism, and headaches when they enlarge and compress adjacent structures. Recurrence after surgical treatment remains challenging despite various surgical approaches. Marsupialization has emerged as an alternative technique for complex recurrent cases, establishing permanent communication between the cyst and the nasal cavity while minimizing surgical risk. We present a case of a 76-year-old man with type 2 diabetes mellitus, a history of meningeal tuberculosis, and panhypopituitarism who experienced progressive visual decline following multiple failed Rathke's cleft cyst surgeries. Ophthalmological evaluation revealed right temporal hemianopsia and reduced visual acuity, and magnetic resonance imaging confirmed a recurrent sellar-suprasellar lesion compressing the optic chiasm. Revision endoscopic endonasal surgery was performed using the marsupialization technique, including a type III sphenoidotomy, cyst aperture, dural membrane eversion toward the nasal cavity, and nasoseptal flap placement on the cyst floor. Surgery was completed without complications. At eight-month follow-up, the patient demonstrated complete resolution of hemianopsia, improved visual acuity, and stable postoperative changes without cyst reaccumulation on imaging. Endoscopic transnasal marsupialization represents a safe and effective therapeutic option for recurrent Rathke's cleft cysts, particularly following multiple failed interventions, providing permanent drainage while minimizing manipulation of delicate neurovascular structures. It may also potentially reduce recurrence rates and improve functional outcomes in complex cases.

A homonymous visual field defect (homonymous hemianopia) is the most common visual dysfunction after a cerebrovascular accident and is associated with involvement of the postchiasmatic pathways (usually the optic radiation or peristriate cortex). Patients with hemianopia experience difficulties with daily activities, such as navigation, visual search, recognition of people and objects, and reading. This review presents current data on use and effectiveness of various non-drug methods for neurorehabilitation in patients with homonymous visual field defects, including approaches for compensation, replacement, and recovery (trainings for restoring vision, stimulus response practices, systematic training of eye movement, use of immersive technologies, multisensory and transcranial non-invasive stimulation, etc.), as well as analyzes the available scientific data on the neurophysiological basis of recovery of patients with hemianopia after a cerebrovascular accident. Activation of neuroplasticity mechanisms underlying rehabilitation in homonymous hemianopia after stroke, and targeted management of cortical reorganization processes, help achieve the best recovery of visual functions.

Metastasis to the pituitary gland is rare, occurring in approximately 1% of pituitary tumors resected via transsphenoidal surgery. We present the second report of metastatic high-grade serous ovarian carcinoma to the pituitary gland, presenting with diabetes insipidus and bilateral hemianopsia. An 86-year-old female patient presented with complaints of dizziness, vertigo, vision changes (peripheral field vision loss), loss of taste, extreme thirst, and fatigue. Urine studies revealed hypotonic hyponatremia, which was consistent with diabetes insipidus. The pituitary magnetic resonance imaging (MRI) scan revealed a sellar and suprasellar hypoenhancing lesion compressing the optic chiasm. The intrasellar portion was heterogeneous, whereas a nodular component along the stalk demonstrated more solid, mild enhancement. The lesion measured 1.8 cm craniocaudally and 7 mm medial-laterally. The lesion presented with compression on the optic chiasm and edema in the proximal optic tracts and hypothalamus. This was a new finding compared with the MRI of the cervical spine as well as prior head computed tomography. An endoscopic transsphenoidal approach to resect the sellar and suprasellar parts of the lesion was performed. Pathology results revealed metastatic adenocarcinoma to the anterior pituitary gland with large areas of necrosis. Immunohistochemistry results revealed that the tumor cells were positive for pankeratin, keratin 7, PAX8, WT1, and estrogen receptor with null-type tumor protein p53 labeling, and negative for keratin 20, TTF1, Napsin-A, GATA3, CDX2, synaptophysin, chromogranin, p16, p63, KIT, and progesterone receptor. The final diagnosis was metastatic adenocarcinoma of Mullerian origin. Following diagnosis, a metastatic workup was done, including a whole-body positron emission tomography (PET) scan, which revealed a 5.1 cm right adnexal ovoid mass and numerous scattered liver metastases. Additionally, the PET scan revealed hypermetabolic right supraclavicular, paratracheal, celiac, and upper aortocaval nodes, consistent with metastatic disease. This report highlights high-grade serous ovarian carcinoma with pituitary metastasis as the initial presentation of systemic cancer.

Hyperosmolar hyperglycemic state (HHS) is a severe complication of uncontrolled diabetes, often presenting with nonlocalizing neurologic symptoms such as encephalopathy. Rarely, focal neurologic deficits like hemianopsia can occur, even with serum osmolality below the diagnostic threshold for HHS. We report two cases of hyperglycemic patients with borderline serum osmolality presenting with neuro-ophthalmologic symptoms. Case 1 involved a 43-year-old male with type 1 diabetes who developed right-sided visual disturbances and was found to have cortical T2/FLAIR hyperintensity and subcortical hypointensity in the left temporal lobe and posterior cingulate gyrus. Case 2 involved a 64-year-old female with untreated type 2 diabetes and hypertension who presented with bright flashes and left homonymous hemianopsia. MRI revealed subtle cortical T2/FLAIR hyperintensity and subcortical hypointensity in the right occipital lobe, findings initially missed on radiological review. In both cases, symptoms resolved with glycemic control and treatment. These cases underscore the importance of recognizing neuro-ophthalmic symptoms as potential manifestations of hyperglycemia, even when serum osmolality is below the diagnostic threshold for HHS. The structural brain changes demonstrated by subtle radiographic findings corresponded to the patients' focal neuro-ophthalmic deficits. The reversibility of these findings with glycemic control highlights the critical need for early recognition and intervention.

This study aimed to describe a case of transient neurologic deficits triggered by euglycemic diabetic ketoacidosis (DKA) in brain tissue at risk due to heavy cerebral amyloid angiopathy (CAA) microbleed burden, while demonstrating the rare imaging finding of reversible T2 fluid-attenuated inversion recovery (FLAIR) subcortical hypointensity.

This study examines the temporal and spatial components of microsaccade dynamics in homonymous hemianopia (HH) after ischemic stroke, and their association with patients' visual impairments. The eye position data were recorded during visual field testing in 15 patients with HH and 15 controls. Microsaccade rate (temporal) and direction (spatial) dynamics in HH were analyzed across visual field sectors with varying defect depth and compared with controls. Support vector machines were trained to characterize the visual field defects in HH based on microsaccade dynamics. Patients exhibited stronger microsaccadic inhibition in the sighted areas, postponed and stronger microsaccadic inhibition in areas of residual vision (ARVs) compared to controls. Meanwhile, a rebound was evident in the sighted areas but absent in the ARVs and blind areas. Microsaccades surviving the inhibition were more attracted toward the stimulus, whereas microsaccades after the inhibition were directed away from the stimulus in controls. Such pattern was not observed in HH. Dissociated temporal and spatial impairments of microsaccade dynamics suggest multi-fold impairments of the visual and oculomotor networks in HH. Based on the microsaccadic phase signature underlying microsaccade rate dynamics, we characterized patients' visual field defects and discovered regions with residual function inside both the blind and sighted hemifields. These findings suggest that monitoring microsaccade dynamics may provide valuable supplementary information beyond that captured by behavioral responses.

Giant thrombosed aneurysms of the posterior cerebral artery are rare and pose significant challenges in both diagnosis and management. We present a case of a 61-year-old woman who had been under observation for 5 years because of a partially thrombosed posterior cerebral artery aneurysm. The aneurysm gradually enlarged to 50 mm, resulting in left hemiparesis and homonymous hemianopsia. Magnetic resonance imaging revealed cerebral edema and contrast enhancement of the aneurysmal wall and intraluminal space. Digital subtraction angiography demonstrated a slowly perfused aneurysm located at the P1-P2 segment, with a medial posterior choroidal artery branching from the short P1 segment. Given the limited microsurgical exposure and the presence of critical perforators, a hybrid approach was selected. Endovascular parent artery occlusion was first performed using coils and n-butyl cyanoacrylate, targeting both the intraluminal space and the vasa vasorum. Seven days later, microsurgical proximal clipping and partial thrombectomy were carried out via a subtemporal approach. Although transient neurologic deterioration occurred postoperatively, significant improvement was observed with rehabilitation. Follow-up imaging showed marked reduction in aneurysmal size and localized infarction in the posterior cerebral artery territory. This case illustrates the effectiveness of a combined endovascular and microsurgical strategy for treating giant thrombosed posterior cerebral artery aneurysms. Individualized treatment planning based on anatomic complexity, collateral flow, and perforator preservation is essential for achieving successful outcomes in such challenging cases.