Anatomical Differences in Sphenoid Sinus During Endoscopic Transsphenoidal Surgery: Comparison Between Nonfunctioning Pituitary Neuroendocrine Tumor (PiTNET) and Growth Hormone-Secreting PiTNET.

BACKGROUND: In surgical practice during endoscopic endonasal approach, growth hormone-secreting pituitary neuroendocrine tumor (GH-secreting PitNET) patients show morphologic differences in the nasal cavities and sinuses, leading to a narrower surgical field and a carotid prominence and potentially increasing the complexity of the surgical and the risk of complications. The aim of the study is to evaluate the anatomical differences of the sphenoid sinus between patients with GH-secreting PitNETs and patients with nonfunctioning pituitary neuroendocrine tumor (NF-PitNET) who underwent endoscopic endonasal approach. METHODS: This is a monocentric retrospective study conducted at the author's institution. The minimum intercarotid distance, the largest diameter of the sphenoid sinus (DSS), and the distance between vomer and clivus (VCD) were collected and compared. Presence, localization, and course of intersphenoid sinus septum were also evaluated. RESULTS: One hundred consecutive patients were identified: 57 males (57%) and 43 females (43%), with a mean age of 55 years. Sixty patients had NF-PitNET (60%) and 40 had GH-secreting PitNET (40%). GH-secreting PitNET group presented inferior values of intercarotid distance (16.8 ± 3.94 mm vs. 20.4 ± 3.94 mm, P < 0.001), DSS (32.5 ± 9.81 mm vs. 38.6 ± 11.03 mm, P = 0.006), and VCD (25.5 ± 6.96 mm vs. 29.6 ± 8.47 mm, P = 0.012) compared to NF-PitNET group. Intersphenoid sinus septum showed no differences between the 2 groups. CONCLUSIONS: Intercarotid distance, DSS, and VCD resulted smaller in acromegalic patients, confirming that patients with GH-secreting PitNETs have a narrower surgical field. A meticulous anatomical preoperative planning and neuronavigation are important to recognize the sphenoid anatomical landmarks in order to reduce the risk of complications, especially in acromegalic patients.

Rathke's cyst with xanthogranulomatous change or chronic cystic craniopharingioma? A rare case.

A 9-year-old girl presented to our neurosurgery clinic complaining of visual disturbances for a week. Magnetic resonance imaging showed an extensive sellar lesion with suprasellar involvement and compression of the optic chiasm. Based on these findings, a cystic craniopharyngioma, a pituitary macroadenoma and - less likely - a Rathke's cleft cyst were considered as differential diagnoses. In view of the progressive loss of vision, the parents agreed to resection of the lesion through an endoscopic endonasal transtubercular approach, with the aim of a gross total resection. Microscopic examination revealed that the lesion was cystic, surrounded by an epithelium that was partly composed of columnar ciliated cells with interspersed mucous cells and partly had a flattened appearance. The observed findings were complex to interpret: if, on the one hand, the clinical-surgical and neuroradiologic data suggested a craniopharyngioma, this hypothesis was not supported by the microscopic data, because the presence of columnar ciliated epithelium associated with mucous cells was a microscopic feature inconsistent with a craniopharyngioma and was instead consistent with a Rathke's cleft cyst, a histologic diagnosis that was made. The incidence of Rathke's cleft cyst, which mimics clinical and neuroradiologic aspects of craniopharyngiomas, is extremely unusual, as only 2 cases have been described in the literature.

Pathogenesis and treatment of a giant occipital bone defect with meningoencephalocele in an NF1 child: case report and review of the literature.

Autosomal dominantly inherited neurofibromatosis type I (NF1) is a systemic disorder caused by a mutation of a gene on chromosome 17q11.2 and characterized by multiple café-au-lait spots, lentiginous macules, Lisch nodules of the iris, and tumors of the nervous system. Bony manifestations such as scoliosis, dysplasia of the greater sphenoidal wing, tibial pseudoarthrosis, short stature, and macrocephaly have been reported in approximately 50% of patients. However, calvarial bone defects are rare. After screening 324 articles, 23 cases (12 adult and 11 pediatric patients) of occipital bone defects in NF1 patients were selected. All patients had a single/multiple bone defect over the lambdoid suture. Adjacent benign plexiform neurofibromas were observed in 14 patients (60.8%, 7 adults and 7 children); one adult patient was diagnosed with neurofibrosarcoma. Meningoencephalocele over the occipital defect was noted in 8 cases (34.78%, all adults). Cranioplasty was performed in only 17.39% of patients. Histologic examination was performed in 7 of the 15 patients with associated neurofibromas/neurofibrosarcomas. Biopsy of the bone margins surrounding the defect was performed in only one case. Pathologic examination of the herniated parieto-occipital or cerebellar tissue was not performed in any of the patients studied. We report the case of a 9-year-old girl with NF1 and a significant occipital bone defect and performed a systematic review of the relevant literature to highlight the challenges in treating this condition and to investigate the underlying mechanisms contributing to bone defects or dysplasia in NF1.