Diffusion-weighted imaging does not seem to be a predictor of consistency in pituitary adenomas.

PURPOSE: To prospectively evaluate the usefulness of T1-weighted imaging (T1WI) and diffusion-weighted imaging (DWI) sequences in predicting the consistency of macroadenomas. In addition, to determine their values ​​as prognostic factors of surgical outcomes. METHODS: Patients with pituitary macroadenoma and surgical indication were included. All patients underwent pre-surgical magnetic resonance imaging (MRI) that included the sequences T1WI before and after contrast administration and DWI with the apparent diffusion coefficient (ADC) map. Post-surgical MRI was performed at least 3 months after surgery. The consistency of the macroadenomas was evaluated at surgery, and they were grouped into soft and intermediate/hard adenomas. Mean ADC values, signal on T1WI and the ratio of tumor ADC values ​​to pons (ADCR) were compared with tumor consistency and grade of surgical resection. RESULTS: A total of 80 patients were included. A softened consistency was found at surgery in 53 patients and hardened in 27 patients. The median ADC in the soft consistency group was 0.532 × 10-3 mm2/sec (0.306 - 1.096 × 10-3 mm2/sec), and in the intermediate/hard consistency group was 0.509 × 10-3 mm2/sec (0.308 - 0.818 × 10-3 mm2/sec). There was no significant difference between the median values ​​of ADC, ADCR and signal on T1W between the soft and hard tumor groups, or between patients with and without tumor residue. CONCLUSION: Our results did not show usefulness of the DWI and T1WI for assessing the consistency of pituitary macroadenomas, nor as a predictor of the degree of surgical resection.

Case report: Regression of Glioblastoma after flavivirus infection.

Glioblastoma is the most frequent and aggressive primary brain cancer. In preclinical studies, Zika virus, a flavivirus that triggers the death of glioblastoma stem-like cells. However, the flavivirus oncolytic activity has not been demonstrated in human patients. Here we report a glioblastoma patient who received the standard of care therapy, including surgical resection, radiotherapy and temozolomide. However, shortly after the tumor mass resection, the patient was clinically diagnosed with a typical arbovirus-like infection, during a Zika virus outbreak in Brazil. Following the infection resolution, the glioblastoma regressed, and no recurrence was observed. This clinical response continues 6 years after the glioblastoma initial diagnosis.

Endoscopic Endonasal Resection of Schwannoma of Pterygopalatine Fossa.

Trigeminal schwannomas are benign slow-growing tumors originating from the peripheral nerve sheath. They account for 0.1%-0.4% of all intracranial tumors and 1%-8% of all intracranial schwannomas.1-3 While most of these tumors develop in the trigeminal ganglion within the middle fossa, trigeminal schwannomas can develop anywhere along the course of the trigeminal nerve. As a result, they can be intradural, interdural, and extradural.4,5 Trigeminal schwannomas from the pterygopalatine fossa (PPF) are extremely rare and very difficult to remove because of limited access to this region and the rich neurovascular contents. Numerous traditional microsurgical approaches to the PPF have been described; however, they are more invasive with increased morbidity.6,7 Therefore, endoscopic endonasal surgery is a feasible solution. This technique allows good visualization of the region with decreased morbidity and a shorter recovery period. A previously healthy, 40-year-old woman presented with right facial pain for 3 weeks. On neurologic examination, the patient had hypoesthesia in the territory of the maxillary (V2) branch of the right trigeminal nerve. She had no other symptoms on physical examination. Cranial computed tomography and magnetic resonance imaging were performed and showed a high signal density mass in the right PPF that exhibited heterogeneous contrast enhancement. She was initially treated with low-dose carbamazepine; however, the dose could not be further increased because of drowsiness and dizziness. Given the size and location of the mass, an endoscopic endonasal approach was performed, and the tumor was successfully resected (Video 1). The postoperative course was uneventful, and the patient had significant improvement of her symptoms and was discharged with no new neurologic deficits. However, she continued to have hypoesthesia of the V2 segment of the trigeminal nerve.

Collision sellar lesions: coexistence of pituitary adenoma and Rathke cleft cyst-a single-center experience.

PURPOSE: Collision sellar lesions represent the coexistence of distinct histopathological lesions found in the sella turcica. They are uncommon entities and have mainly been reported as pituitary adenoma (PA) associated to Rathke cleft cyst (RCC). Pre- and perioperative diagnosis is difficult, since most of the cases appear clinically, radiologically, and macroscopically as solitary cystic sellar lesion. METHODS: A retrospective study of histological reports from patients operated for PA from 2013 to 2018 in a single neurosurgery reference center was performed. Patients who also exhibited RCC in the histological sections were included. Clinical and biochemical data were collected from medical files. MRI scans and histopathological slides were also reviewed. RESULTS: Among 554 PA, five patients (0.9%) presented the association of PA and RCC. At diagnosis, patients had median age of 60 years (33-78) with, at least, one pituitary dysfunction, and visual field loss and/or headache. There was a female predominance (n = 3). All patients had nonfunctioning PA. MRI studies showed a predominantly cystic lesion and were unable to distinguish both lesions. The definitive diagnosis was made by histopathology. CONCLUSION: The association of PA and RCC is extremely rare. On MRI, they appear as a solid-cystic or cystic sellar tumors. RCC can rupture causing granulomatous reaction with cholesterol crystal formation, which can be mistaken for craniopharyngiomas during surgery. Therefore, collision sellar lesion must be included in the differential diagnosis of cystic sellar lesions. The definitive diagnosis is made by histological study.

Predictors of surgical outcome and early criteria of remission in acromegaly.

BACKGROUND: Transsphenoidal surgery (TSS) is the cornerstone of acromegaly treatment, however there are no robust predictors of surgical outcome and remission can only be defined three months after surgery. PURPOSE: To analyze if biochemical, demographical, radiological, and immunohistochemical characteristics are predictors of surgical remission and investigate if immediate postoperative GH and IGF-I levels can help defining remission earlier. METHODS: Consecutive acromegaly patients submitted to TSS between 2013-2016 were evaluated. Remission criteria was defined as normal IGF-I and GH <1 mcg/L three months after surgery. Data of age, sex, GH and IGF-I levels, tumor volume, cavernous sinus invasion, T2-weighted signal, Ki-67, and granulation pattern were correlated with remission status. GH and IGF-I levels at 24, 48 h, and one week postoperative were evaluated as early criteria of remission. RESULTS: Sixty-nine patients were included (84% macroadenomas) and surgical remission was achieved in 45%. No difference between cured and not cured patients concerning age, gender, preoperative GH or IGF-I levels, tumor volume, T2-weighted signal, Ki-67 and tumor granularity was observed. Remission was obtained in 20 of 36 (56%) of the non-invasive tumors, and in 3 of 16 (19%) of the invasive tumors (p = 0.017). A GH <1.57 mcg/L 48 h after surgery was able to predict remission with 93% sensitivity and 86% specificity and an IGF-I < 231% ULNR one week after surgery predicted remission with 86% sensitivity and 93% specificity. CONCLUSION: Cavernous sinus invasion is the only preoperative predictor of surgical remission. GH at 48 h and IGF-I one week after surgery can define earlier not cured patients.

Trigeminal Neuralgia due to Vertebrobasilar Dolichoectasia.

We presented a case of drug-resistant trigeminal neuralgia attributed to vertebrobasilar dolichoectasia, a rare condition characterized by enlargement, tortuosity, or elongation of intracranial arteries. Dolichoectatic vessels can cause dysfunction of cranial nerves through direct vascular compression. The relationships of vertebrobasilar dolichoectasia with the particularities of neurovascular conflict and images findings are discussed.