Pre- and postoperative magnetic resonance imaging appearance of the normal residual pituitary gland following macroadenoma resection: Clinical implications.

BACKGROUND: To assess the relationship between the preoperative magnetic resonance imaging (MRI) appearance of the normal residual pituitary gland (NRPG) and pituitary functional outcome following transsphenoidal resection of pituitary macroadenomas. METHODS: We retrospectively reviewed the medical records of 100 consecutive patients with a pituitary macroadenoma, who underwent transsphenoidal resection. The preoperative configuration of the displaced NRPG was stratified as superior, superolateral or lateral. The extent of postoperative restitution of the NRPG was divided into four groups: Group 1 - normal residual gland or almost normal; Group 2 - more than 50% restitution; Group 3 - less than 50% of the normal residual gland; and Group 4 - barely visible or absent residual gland. The pre- and postoperative NRPG appearance was correlated with pituitary functional status. RESULTS: Preoperatively, the NRPG was identifiable in 79 patients, with extrasellar displacement in 53%. The displacement pattern was superior in 8%, superolateral in 32%, and lateral in 58% of the patients. If the NRPG was displaced laterally, the ipsilateral cavernous sinus was not invaded by the pituitary macroadenoma. Partial or complete pituitary function was lost in 6 / 23 (26.1%) patients with superior or superolateral displacement of the NRPG, compared to only 1 / 36 (2.8%) patients without superior displacement of the NRPG (P = 0.025). Progressive postoperative reconstitution of the NRPG was related to the preservation of the pituitary hormonal axis (Pearson Chi-Square P < 0.001). CONCLUSIONS: Progressive displacement of the NRPG preoperatively, and lack of restitution of the NRPG on postoperative MRI appeared to correlate with the postoperative pituitary functional loss.

Management of Rathke's cleft cysts.

BACKGROUND: Incidental diagnosis of Rathke's cleft cysts (RCCs) has increased due to the improvements in imaging techniques; however, symptomatic cases are rare and accurate preoperative diagnosis can be difficult. METHODS: Files and magnetic resonance imaging (MRI) of 10 surgically treated patients with RCC and 8 conservatively managed cases with a suspected diagnosis were reviewed retrospectively. Clinical, radiological, and histological features as well as intraoperative findings were scrutinized. RESULTS: In the surgical group, headache was present in 4 patients, hormonal abnormality in 4, visual deficits in 3, and otolaryngological symptoms in 2. Two of the nonsurgical cases had hyperprolactinemia, and the remaining were asymptomatic. The cyst had suprasellar extension (SSE) in 9 patients and was entirely suprasellar in 1 in the surgical group. It was purely intrasellar in 6 nonsurgical cases and had SSE in 2. The cyst content showed hyperintense MRI signal in the majority of T1 and T2 images in both groups. Transsphenoidal surgery was performed in 8 and transcranial surgery in 2 patients. Squamous metaplasia and inflammation was present in 3 cases each. Initial hormonal deficiencies did not improve postoperatively and new deficits were observed in 2 cases. There was no recurrence with an average follow-up of 32 months. CONCLUSIONS: Rathke's cleft cysts is a rare pathology with a wide spectrum of clinical and radiological features. Reactive inflammation of the normal pituitary gland may have a role in the pathogenesis of hormonal deficiency, in addition to compression. Preoperative recognition of the anteriorly displaced normal residual gland may be important in avoiding postoperative hormonal deficiency after transsphenoidal approach.

Distortion of normal pituitary structures in sellar pathologies on MRI.

OBJECTIVE: This study was undertaken to assess the displacement patterns and shifts of the normal pituitary gland in sellar pathologies on MRI and to determine if the position of the bright spot (BS) represents a predicting factor for the position of the residual adenohypophysis (RAH) in pathological conditions. METHODS: In a control group of 102 patients without any pituitary pathology, the presence of the BS was evaluated. In 100 patients with intra- or suprasellar pathologies, presence and respective topography of BS and RAH were scrutinized on MRI, according to lesion type, size, endocrine status and intra-operative findings in the surgical group. RESULTS: The BS was visible in 91.2% of 102 cases in the control group, as compared to 75 of the 100 patients with sellar lesions. Location of RAH was identified in 58% of the patients, and RAH enhanced more than the lesion in all cases after contrast infusion. The RAH was identified in 65.3% of the 75 "BS positive" patients, as compared to 36% of the 25 "BS negative". The normal residual gland was visualized intra-operatively in 63.5% of the 52 operated patients: in 37 "BS positive" patients, it was visualized intra-operatively in 81.1% and in 28 "RAH positive" patients, it was identified in 82.1%. CONCLUSIONS: The BS can be identified in the majority and RAH in more than half of the cases with pituitary lesions on MRI. Positions of both the BS and RAH help predict the location of the normal residual gland during surgery and, therefore, may contribute to preserving the pituitary function.