Tara Kearney

Endoscopic transsphenoidal pituitary surgery: evidence of an operative learning curve.

BACKGROUND:The use of the fiberoptic endoscope is a recent innovation in pituitary surgery. OBJECTIVE:To investigate the evidence of an operative learning curve after the introduction of endoscopic transsphenoidal surgery in our unit. METHODS:The first 125 patients who underwent endoscopic transnasal transsphenoidal surgery for pituitary fossa lesions between 2005 and 2007 performed by 1 surgeon were studied. Changes in a number of parameters were assessed between 2 equal 15-month time periods: period 1 (53 patients) and period 2 (72 patients). RESULTS:There were 67 patients (54%) with nonfunctioning adenomas, 22 (18%) with acromegaly, and 10 (8%) with Cushings disease. Between study periods 1 and 2, there was a decrease in the mean duration of surgery for nonfunctioning adenomas (from 120 minutes to 91 minutes; P < .01). This learning effect was not apparent for functioning adenomas, the surgery for which also took longer to perform. The proportion of patients with an improvement in their preoperative visual field deficits increased over the study period (from 80% to 93%; P < .05). There were nonsignificant trends toward improved endocrine remission rates for patients with Cushings disease (from 50% to 83%), but operative complications, notably the rates of hypopituitarism, did not change. Overall length of hospital stay decreased between time periods 1 and 2 (from 7 to 4 days median; P < .01). CONCLUSION:The improvements in the duration of surgery and visual outcome noted after about 50 endoscopic procedures would favor the existence of an operative learning curve for these parameters. This further highlights the benefits of subspecialization in pituitary surgery.

Acromegaly surgery in Manchester revisited - The impact of reducing surgeon numbers and the 2010 consensus guidelines for disease remission.

Introduction  Surgical remission rates for acromegaly vary and are dependent on the tumour morphology, biochemical definition of disease remission and surgical expertise. A previous report from the Manchester region in 1998 reported an overall surgical remission rate of 27% using accepted criteria for biochemical remission at the time. The establishment of the 2010 Consensus guidelines further tightens biochemical criteria for remission. This report aims to assess the impact of establishing a specialist pituitary surgery service in Manchester in 2005, with reduced surgeon numbers on the remission rates for acromegaly surgery.

Pituicytoma: A misdiagnosed benign tumour of the posterior pituitary

A 77-year-old man presented with hypogonadism and bitemporal inferior quadrantonopia. Endocrine testing revealed decreased levels of gonadotrophins and testosterone. The prolactin levels were slightly raised at 586, suggesting a stalk effect. A magnetic resonance scan revealed a 2-cm suprasellar lesion, above a normally sited pituitary gland (Fig. 1a). There was uniform enhancement with gadolinium (Fig. 1b). The lesion was clinically and radiologically presumed to be a craniopharyngioma. Given his significant co-morbidity (ischaemic heart disease, hypertension and diabetes mellitus), an extended transnasal transphenoidal subtotal resection of the tumour was undertaken. The tumour was fibrous and vascular, and only the anterior part of the tumour was resected to decompress the optic chiasm. Histopathology revealed spindle shaped cells with little nuclear pleomorphism and no mitoses (Fig. 2a). The proliferation index with Ki-67 was less than 2%. The tumour showed GFAP-immunoreactivity with some positivity for S-100 (Fig. 2b). These findings met the criteria proposed by Brat et al. for the diagnosis of pituicytoma. Pituicytomas are rare benign primary astrocytic tumours of the neurohypophysis. – 3 Their rarity has led to these tumours in the suprasellar region being confused with more common neoplasms, such as craniopharyngiomas, germ cell tumours, granular cell tumours or rarely a suprasellar meningioma. Although there are no pathognomonic radiological features, a dynamic MR after gadoliniuim injection can show a rapid early phase enhancement of the tumour, which may reflect well developed capillary network. The diagnosis is usually histological with

Predictors of outcome in myxoedema coma

Myxoedema coma is a rare and life-threatening illness the outcome of which has not been robustly studied in large numbers, partly due to its low incidence. Dutta and colleagues have explored outcome predictors in a developing country where access to thyroid function tests is more limited than in the Western world. Cardiovascular instability, reduced consciousness, persistent hypothermia, and sepsis all contributed to a poorer outcome, as has been demonstrated before, but a generic outcome predictor model was shown to be useful in this group of patients. Unfortunately, this observational study was unable to show differences in outcome based on replacement treatment methods and the mortality remains at 40%.

Transient asystole during endoscopic transsphenoidal surgery for Acromegaly: an example of trigeminocardiac reflex

Cardiac arrhythmias are rare during transsphenoidal surgery and is often secondary to stimulation of the trigeminal nerve endings that supply the nasal passages and cavernous sinus walls. Authors report a patient with Acromegaly, who developed transient asystole, during the dissection of the adenoma extending into the left cavernous sinus wall. In such cases, the use of prophylactic atropine may help to avoid such a complication.

Extraventricular neurocytoma of the sellar region

Abstract Objective. Extra-ventricular neurocytoma (EVN) is rare, mainly described within the cerebral hemispheres or spinal cord. We report a case of sellar neurocytoma presenting with chiasmal compression. Clinical presentation. A 50-year-old woman presented with decreasing vision and a bitemporal field deficit. CT and MRI demonstrated an enhancing invasive sellar lesion extending into the sphenoid sinus and left cavernous sinus, with speckled calcification and compression of the optic chiasm. Pituitary function was normal apart from a mildly elevated prolactin level consistent with stalk effect. Intervention. Endoscopic trans-sphenoidal resection of the lesion was performed revealing a firm, vascular tumour. Some residual tumour was left within the left cavernous sinus. Histology revealed a neurocytic tumour with nests, islands and strands of neuropil. Diffuse synaptophysin, chromogranin, neurofilament protein and CD56 positivity was seen. A histological diagnosis of EVN, WHO grade II was made and adjuvant radiotherapy was given for the residual tumour. Conclusion. This is only the second case of neurocytoma of the sella reported. It should be considered in the differential diagnoses of sellar lesions that appear radiologically atypical for pituitary adenomas.

Pituitary apoplexy – bespoke patient management allows good clinical outcome

To describe the clinical presentation, management and outcome of pituitary apoplexy from a single centre and retrospectively apply the Pituitary Apoplexy Score (PAS).

Nasal symptoms following endoscopic transsphenoidal pituitary surgery: assessment using the General Nasal Patient Inventory.

OBJECT The endoscopic approach for pituitary tumors is a recent innovation and is said to reduce the nasal trauma associated with transnasal transsphenoidal surgery. The authors assessed the temporal changes in the rhinological symptoms following endoscopic transsphenoidal surgery for pituitary lesions, using the General Nasal Patient Inventory (GNPI). METHODS The GNPI was administered to 88 consecutive patients undergoing endoscopic transsphenoidal surgery at 3 time points (presurgery, 3-6 months postsurgery, and at final follow-up). The total GNPI score and the scores for the individual GNPI questions were calculated and differences between groups were assessed once before surgery, several months after surgery, and at final follow-up. RESULTS Of a maximum possible score of 135, the mean GNPI score at 3-6 months postsurgery was only 12.9 ± 12 and was not significantly different from the preoperative score (10.4 ± 13) or final follow-up score (10.3 ± 10). Patients with functioning tumors had higher GNPI scores than those with nonfunctioning tumors for each of these time points (p < 0.05). Individually, a mild increase in symptom severity was seen for symptoms attributable to the nasal trauma of surgery, with partial recovery (nasal sores and bleeding) or complete recovery (nasal blockage, painful sinuses, and unpleasant nasal smell) by final follow-up (p < 0.05). Progressive improvements in symptom severity were seen for symptoms more attributable to tumor mass preoperatively (for example, headaches and painkiller use [p < 0.05]). In total, by final follow-up 8 patients (9%) required further treatment or advice for ongoing nasal symptoms. CONCLUSIONS Endoscopic transsphenoidal surgery is a well-tolerated minimally invasive procedure for pituitary fossa lesions. Overall patient-assessed nasal symptoms do not change, but some individual symptoms may show a mild worsening or overall improvement.

Pituitary adenoma and incidental superior hypophyseal aneurysm.

In patients with pituitary adenomas, intra-cranial aneurysms can be an incidental finding, and are usually located outside the pituitary region. The authors describe the multi-modal management of a rare case of an aneurysm of the supraclinoid carotid that encroached into a pituitary macroadenoma.

In-frame seven amino-acid duplication in AIP arose over the last 3000 years, disrupts protein interaction and stability and is associated with gigantism.

Objective Mutations in the aryl hydrocarbon receptor-interacting protein (AIP) gene are associated with pituitary adenoma, acromegaly and gigantism. Identical alleles in unrelated pedigrees could be inherited from a common ancestor or result from recurrent mutation events. Design and methods Observational, inferential and experimental study, including: AIP mutation testing; reconstruction of 14 AIP-region (8.3 Mbp) haplotypes; coalescent-based approximate Bayesian estimation of the time to most recent common ancestor (tMRCA) of the derived allele; forward population simulations to estimate current number of allele carriers; proposal of mutation mechanism; protein structure predictions; co-immunoprecipitation and cycloheximide chase experiments. Results Nine European-origin, unrelated c.805_825dup-positive pedigrees (four familial, five sporadic from the UK, USA and France) included 16 affected (nine gigantism/four acromegaly/two non-functioning pituitary adenoma patients and one prospectively diagnosed acromegaly patient) and nine unaffected carriers. All pedigrees shared a 2.79 Mbp haploblock around AIP with additional haploblocks privately shared between subsets of the pedigrees, indicating the existence of an evolutionarily recent common ancestor, the ‘English founder’, with an estimated median tMRCA of 47 generations (corresponding to 1175 years) with a confidence interval (9–113 generations, equivalent to 225–2825 years). The mutation occurred in a small tandem repeat region predisposed to slipped strand mispairing. The resulting seven amino-acid duplication disrupts interaction with HSP90 and leads to a marked reduction in protein stability. Conclusions The c.805_825dup allele, originating from a common ancestor, associates with a severe clinical phenotype and a high frequency of gigantism. The mutation is likely to be the result of slipped strand mispairing and affects protein–protein interactions and AIP protein stability.