The role of outcomes data for assessing the expertise of a pituitary surgeon

PURPOSE OF REVIEW

Over the past four decades, advances in surgical technique, instrumentation, and anatomical knowledge have fueled the evolution and sophistication of transsphenoidal pituitary surgery. Paralleling these advances have been major improvements in endocrinological and overall clinical outcomes in patients with pituitary adenomas and other parasellar lesions such as Rathke's cleft cysts and craniopharyngiomas. In this review, we assess the impact of neurosurgeon expertise as a determinant of outcome in pituitary surgery.

RECENT FINDINGS

Published data since the 1980s indicate that remission rates, overall clinical outcomes and surgical complication rates in pituitary and parasellar surgery are related to neurosurgeon practice volume and cumulative clinical experience. More recently, pituitary surgery has been increasingly performed using an endonasal endoscopic approach. Reports over the last decade suggest when an experienced pituitary neurosurgeon performs a fully endoscopic or endoscope-assisted tumor removal; outcomes are similar if not better than when performed by a traditional microscopic transsphenoidal approach.

SUMMARY

A focused clinical practice and large transsphenoidal surgical volume appear to be important outcome determinants for patients with pituitary and parasellar tumors. Strategies that may further improve patient outcomes include establishing guidelines for pituitary tumor centers of excellence and more focused residency and fellowship training in endonasal endoscopic transsphenoidal surgery. Encouraging regionalization of care to higher volume pituitary tumor centers of excellence and promoting patient education on the importance of surgical expertise may further enhance pituitary patient outcomes.

Endonasal transsphenoidal surgery and multimodality treatment for giant pituitary adenomas

OBJECTIVE

Giant pituitary adenomas (> or =40 mm) pose a major management challenge. We describe the experience of a single surgeon and a dedicated neuro-endocrine team with multimodality treatment of these tumours in three specialized institutions.

DESIGN

Retrospective data set analyses.

PATIENTS

Fifty-one consecutive patients with a giant adenoma (39 endocrine-inactive, 12 endocrine-active; mean tumour diameter 45 mm) treated over 10 years by an endonasal transsphenoidal approach were included. All patients had surgical resection followed by radiotherapy and/or medical therapy as judged necessary.

MEASUREMENTS

Hormonal and visual status, extent of resection, tumour control rates, complications and use of medical and radiotherapy were evaluated.

RESULTS

Surgery resulted in gross total, near total and subtotal removal in21 (41%), 10 (20%) and 20 (39%) patients respectively. Complete tumour removal was associated with absence of cavernous sinus invasion (P < 0.001). Long-term endocrine function improved in 49% of patients and new endocrinopathy occurred in 14.6%; 76% required long-term hormone replacement therapy. Vision improved in 81.5% of the patients and there was no visual worsening. At the last follow up (median 30 months), tumour control was achieved in 96% of patients: 59% with surgery alone, 20% with surgery plus focussed radiotherapy, 18% with surgery and medical therapy and two with all three modalities.

CONCLUSIONS

Endonasal surgery provides effective initial treatment for patients with giant adenomas. Multimodality therapy was needed in almost 50% of patients and this rate will likely increase with longer follow up. Close collaboration of neurosurgeons with endocrinologists and radiation oncologists is essential for optimal treatment of patients with these challenging tumours.

Endonasal versus supraorbital keyhole removal of craniopharyngiomas and tuberculum sellae meningiomas

OBJECTIVE

Endonasal and supraorbital "eyebrow" craniotomies are increasingly being used to remove craniopharyngiomas and tuberculum sellae meningiomas. Herein, we assess the relative advantages, disadvantages, and selection criteria of these 2 keyhole approaches.

METHODS

All consecutive patients who had endonasal or supraorbital removal of a craniopharyngioma or tuberculum sellae meningioma were analyzed.

RESULTS

Of 43 patients, 22 had a craniopharyngioma (18 endonasal, 4 supraorbital), and 21 had a meningioma (12 endonasal, 7 supraorbital, 2 both routes); 33% had prior surgery. Craniopharyngiomas were primarily retrochiasmal in location in 78% of endonasal cases versus 25% of supraorbital cases (P = 0.08). Meningiomas were larger when approached by the supraorbital route versus the endonasal route (33 +/- 10 versus 25 +/- 8 mm, respectively; P = 0.008). Endoscopy was used in 84% of endonasal approaches and in 31% of supraorbital approaches (P = 0.001). Of patients having first-time surgery for a craniopharyngioma (n = 14) or meningioma (n = 15), total/near total removal was achieved in 83% and 80% of patients by the endonasal route and in 50% and 80% of patients by the supraorbital route, respectively. Vision improved in 87% and 70% of patients who had surgery by an endonasal versus supraorbital route, respectively (P = 0.3). Visual deterioration occurred in 2 patients with meningiomas, 1 by endonasal (7%), and 1 by supraorbital (11%) removal. The endonasal approach was associated with a higher rate of postoperative cerebrospinal fluid leaks (16 versus 0%; P = 0.3), 4 of 5 of which occurred in patients with meningioma.

CONCLUSION

The endonasal route is preferred for removal of most retrochiasmal craniopharyngiomas, whereas the supraorbital route is recommended for meningiomas larger than 30 to 35 mm or with growth beyond the supraclinoid carotid arteries. For smaller midline tumors, either approach can be used, depending on surgeon experience and tumor anatomy. Compared with traditional craniotomies, the major limitation of both approaches is a narrow surgical corridor. The endonasal approach has the added challenges of restricted lateral suprasellar access, a greater need for endoscopy, and a more demanding cranial base repair.

The endonasal microscopic approach for pituitary adenomas and other parasellar tumors: a 10-year experience

THE DIRECT ENDONASAL transsphenoidal approach to the sella with the operating microscope was initially described more than 20 years ago. Herein, we describe the technique, its evolution, and lessons learned over a 10-year period for treating pituitary adenomas and other parasellar pathology. From July 1998 to January 2008, 812 patients underwent a total of 881 operations for a pituitary adenoma (n = 605), Rathke's cleft cyst (n = 59), craniopharyngioma (n = 26), parasellar meningioma (n = 23), chordoma (n = 18), or other pathological condition (n = 81). Of these, 118 operations (13%) included an extended approach to the suprasellar, infrasellar/clival, or cavernous sinus regions. Endoscopic assistance was used in 163 cases (19%) overall, including 36% of the last 200 cases in the series and 18 (72%) of the last 25 extended endonasal cases. Surgical complications included 19 postoperative cerebrospinal fluid leaks (2%), 6 postoperative hematomas (0.7%), 4 carotid artery injuries (0.4%), 4 new permanent neurological deficits (0.4%), 3 cases of bacterial meningitis (0.3%), and 2 deaths (0.2%). The overall complication rate was higher in the first 500 cases in the series and in extended approach cases. Major technical modifications over the 10-year period included increased use of shorter (60-70 mm) endonasal speculums for greater instrument maneuverability and visualization, the micro-Doppler probe for cavernous carotid artery localization, endoscopy for more panoramic visualization, and a graded cerebrospinal fluid leak repair protocol. These changes appear to have collectively and incrementally made the approach safer and more effective. In summary, the endonasal approach provides a minimally invasive route for removal of pituitary adenomas and other parasellar tumors.

PITUITARY HORMONAL LOSS AND RECOVERY AFTER TRANSSPHENOIDAL ADENOMA REMOVAL

OBJECTIVE

Transsphenoidal adenomectomy carries the possibility of new pituitary failure and recovery. Herein, we present rates and determinants of postoperative hormonal status.

METHODS

All consecutive patients who underwent endonasal transsphenoidal adenoma removal over an 8-year period were analyzed. Those with previous sellar radiotherapy were excluded. Pre- and postoperative hormonal status (at least 3 mo after surgery) were determined and correlated with clinical parameters using a multivariate statistical model.

RESULTS

Of 444 patients (median age 45 years, 75% macroadenoma, 19% with multiple operations), 9 had preoperative panhypopituitarism. Of the remaining 435 patients, new hypopituitarism occurred in 5.5% of patients (anterior loss in 5%; permanent diabetes insipidus in 2.1%; including 2 patients who had total hypophysectomy). Of 346 patients with preoperative hormonal dysfunction, 170 (49%) had improved function. “Stalk compression” hyperprolactinemia resolved in 73% of 133 patients; recovery of at least 1 other anterior axis (excluding isolated hypogonadism associated with “stalk compression” hyperprolactinemia) occurred in 24% of 209 patients. Multivariate analysis showed that new hypopituitarism was most strongly associated with larger tumor diameter (P = 0.04). Of 223 patients with an endocrine-inactive adenoma, new hypopituitarism was seen in 0, 7.2, and 13.6% of patients with tumor diameters of &lt;20, 20 to 29, and ≥30 mm, respectively (P = 0.005). Multivariate analysis revealed that resolution of hypopituitarism was related to younger age (39 versus 52 years, P &lt; 0.0001), absence of an intraoperative cerebrospinal fluid leak and, in patients with an endocrine-inactive adenoma, absence of systemic hypertension (24% versus 6%, P = 0.009).

CONCLUSION

After transsphenoidal adenomectomy, new unplanned hypopituitarism occurs in approximately 5% of patients, whereas improved hormonal function occurs in 50% of patients. The likelihood of new hormonal loss or recovery appears to depend on several factors. New hypopituitarism occurs most commonly in patients with tumors larger than 20 mm in size, whereas hormonal recovery is most likely to occur in younger, nonhypertensive patients and those without an intraoperative cerebrospinal fluid leak.

Early pathogenesis of experimental reovirus infection in chickens

One-day-old specific-pathogen-free, light hybrid chickens were infected orally with an avian arthrotropic reovirus and examined at intervals from 2 h until 12 days after infection. Entry, primary replication and spread of virus were studied by infectivity assay, immunohistochemical study and electron microscopy in a wide range of tissues. These showed viral entry and primary replication in the epithelium of intestine and bursa of Fabricius within 12 h after oral infection. These were followed by a rapid and pantropic distribution of virus which reached most tissues within 24 to 48 h after infection.

Chronic hypopituitarism after traumatic brain injury: risk assessment and relationship to outcome

OBJECTIVE

Chronic pituitary dysfunction is increasingly recognized as a sequela of traumatic brain injury. We sought to define the incidence, risk factors, and neurobehavioral consequences of chronic hormonal deficiencies after complicated mild, moderate, or severe traumatic brain injury.

METHODS

Patients aged 14 to 80 years were prospectively enrolled at the time of injury and assessed at 3 and 6 to 9 months after injury for hormonal function and neurobehavioral consequences. Major and minor (subclinical) hormonal deficiencies, including growth hormone deficiency (GHD) and growth hormone insufficiency (GHI), were identified. Acute injury characteristics, neurobehavioral, and quality of life measures were compared in patients with and without major hormonal deficits by the use of multivariate analysis.

RESULTS

Out of 70 patients (mean age, 32 yr; median Glasgow Coma Scale score, 7; 19% women) tested at 6 to 9 months after injury, 15 (21%) had at least one major hormonal deficiency, 20 (29%) had minor deficiencies, and 30 (43%) had major and/or minor deficiencies. Patients with major deficiencies included 16% with GHD or GHI, 10.5% with hypogonadism, and 1.4% with diabetes insipidus. None of the patients required adrenal or thyroid replacement. At 6 to 9 months after injury, patients with major hormonal deficits had more abnormal acute computed tomographic findings (P = 0.014), greater acute and chronic body mass index (P < 0.01), and a worse Disability Rating Scale score (multivariate P = 0.04). Compared with the 59 growth hormone-sufficient patients, the 11 patients with GHD or GHI had worse Disability Rating Scale scores (multivariate P = 0.04), greater rates of depression, (90 versus 53%; multivariate P = 0.06), and worse quality of life in the Short Form-36 domains of energy and fatigue (multivariate P = 0.03), emotional well-being (multivariate P = 0.02), and general health (multivariate P = 0.07).

CONCLUSION

Chronic hypopituitarism warranting hormone replacement occurs in approximately 20% of patients after complicated mild, moderate, or severe traumatic brain injury and is associated with more severe brain injuries and increased disability. GHD and GHI are also associated with increased disability, poor quality of life, and a greater likelihood of depression. The clinical significance of minor hormonal deficits, which occur in almost 30% of patients, warrants further study. Given that major deficiencies are readily treatable, routine pituitary hormonal testing within 6 months of injury is indicated for this patient population.

Seroprotection against serogroup C meningococcal disease in adolescents in the United Kingdom: observational study

OBJECTIVE

To determine the persistence of bactericidal antibody titres following immunisation with serogroup C meningococcal glycoconjugate vaccine at age 6-15 years in order to examine changes in persistence of antibodies with age.

DESIGN

Observational study.

SETTING

Secondary and tertiary educational institutions in the United Kingdom.

PARTICIPANTS

Healthy adolescents aged 11-20 years previously immunised between 6 and 15 years of age with one of the three serogroup C meningococcal vaccines.

INTERVENTION

Serum obtained by venepuncture.

MAIN OUTCOME MEASURES

Percentage of participants with (rabbit complement) serum bactericidal antibody titres of at least 1:8; geometric mean titres of serogroup C meningococcal serum bactericidal antibody.

RESULTS

Five years after immunisation, 84.1% (95% confidence interval 81.6% to 86.3%) of 987 participants had a bactericidal antibody titre of at least 1:8. Geometric mean titres of bactericidal antibody were significantly lower in 11-13 year olds (147, 95% confidence interval 115 to 188) than in 14-16 year olds (300, 237 to 380) and 17-20 year olds (360, 252 to 515) (P<0.0001 for both comparisons). Within these age bands, no significant difference in geometric mean titres of bactericidal antibody between recipients of the different serogroup C meningococcal vaccines was seen. More than 70% of participants had received a vaccine from one manufacturer; in this cohort, geometric mean titres were higher in those immunised at aged 10 years or above than in those immunised before the age of 10.

CONCLUSIONS

Higher concentrations of bactericidal antibody are seen five years after immunisation with serogroup C meningococcal vaccine at age 10 years or above than in younger age groups, possibly owing to immunological maturation. This provides support for adolescent immunisation programmes to generate sustained protection against serogroup C meningococcal disease not only for the vaccine recipients but also, through the maintenance of herd immunity, for younger children.

A Short Trapezoidal Speculum for Suprasellar and Infrasellar Exposure in Endonasal Transsphenoidal Surgery

Objective:

A key limitation of the transsphenoidal approach for suprasellar and infrasellar lesions is restricted exposure. Microscope and endoscope-assisted procedures have traditionally used an oval-shaped speculum, the distal end of which restricts superior and inferior visualization. To improve visualization and use of the endoscope, shorter specula, with a trapezoidal distal end, were designed.

Methods:

The new specula have a working length of 60 mm. The proximal 20-mm segment is oval-shaped to conform to the nostril; the middle 20-mm segment has vertically oriented blades; and the distal 20-mm segment transitions to a trapezoidal orientation, with the distal blades angled 15 degrees upward and outward on the suprasellar speculum, or 15 degrees downward and outward on the infrasellar speculum. Both specula have a 5-degree distal outward flare. The upward-angled trapezoidal 60-mm speculum was compared with 70- and 80-mm oval specula in a transsphenoidal clay model. A pen light was projected from the nasal speculum end to a target 100 mm away using a blade opening width of 16 mm. Line drawings were made to quantify the impact of speculum length on the horizontal angle of exposure. The clinical utility of the trapezoidal specula was also assessed.

Results:

In the model, the 60-mm upward-angled trapezoidal speculum yielded a surface area illumination of 759 mm2, as compared with 579 and 432 mm2 with the 70-and 80-mm oval specula, an increase in exposure of 31 and 76%, respectively. In the line drawings, the 60-mm speculum provided a horizontal angle of exposure of 30 degrees, as compared with 26 and 23 degrees for the 70- and 80-mm specula, an increase of 17 and 33%, respectively. In patients, provided sufficient mucosa and bone are removed from the posterior nasal cavity, the trapezoidal specula provide an expanded working volume that facilitates endoscopy.

Conclusion:

Short upward- or downward-angled trapezoidal endonasal specula increase parasellar surface area exposure and the horizontal angle of exposure. Initial clinical experience suggests that reducing the speculum length and eliminating the distal curved blades result in greater instrument maneuverability and enhanced visibility for removing parasellar tumors.

Endonasal microscopic removal of clival chordomas

INTRODUCTION

Clival chordomas have traditionally been removed using a variety of anterior and lateral skull base approaches. Herein, we evaluate the outcomes of patients who underwent an extended endonasal transsphenoidal removal of a clival chordoma.

METHOD

All consecutive patients with a clival chordoma treated using an endonasal microscope approach were identified. In 8 cases, frameless surgical navigation was used, and in 4 cases, endoscopic assistance was used. Patients treated with prior radiotherapy were excluded.

RESULT

Over 5 years, 18 procedures were performed on 14 patients (7 females; mean age, 47 years). Patients were followed from 3 to 58 months (median, 20 months). Mean tumor diameter was 32 +/- 17 mm; 7 (50%) patients had intradural extension. Postoperative MRIs after the initial operation showed gross total, near-total (>90%), and subtotal resection in 43%, 43%, and 14% of patients, respectively. Use of the endoscope was associated with gross total or near-total tumor removal in 4 of 4 cases. Tumor regrowth occurred in 2 (14%) cases 10 and 12 months after the initial surgery and before radiotherapy. Two patients had multiple operations, in one as a planned staged operation, and in the other, 3 additional debulkings were performed despite an initial gross total removal. Nine patients, all with CS invasion, had subsequent stereotactic radiation. Of 10 patients with cranial neuropathy, 80% improved or resolved including 75% and 67% of sixth and fifth CN palsies, respectively. Complications included one each of adrenal insufficiency and chemical meningitis. There were no CSF leaks or new neurological deficits.

CONCLUSION

In this small series with relatively short follow-up, endonasal microscopic removal of clival chordomas proved safe and elfective with gross total or near-total removal in 86% of patients and improvement of cranial neuropathy in 80% of patients. Endoscopy for aiding tumor removal and assessing completeness of resection, as well as surgical navigation, are recommended for all cases.

Transsphenoidal surgery for Cushing's disease: a review of success rates, remission predictors, management of failed surgery, and Nelson's Syndrome

Cushing's disease is a serious endocrinopathy that, if left untreated, is associated with significant morbidity and mortality rates. After diagnostic confirmation of Cushing's disease has been made, transsphenoidal adenomectomy is the treatment of choice. When a transsphenoidal adenomectomy is performed at experienced transsphenoidal surgery centers, long-term remission rates average 80% overall, surgical morbidity is low, and the mortality rate is typically less than 1%. In patients with well-defined noninvasive microadenomas, the long-term remission rate averages 90%. For patients in whom primary surgery fails, treatment options such as bilateral adrenalectomy, stereotactic radiotherapy or radiosurgery, total hypophysectomy, or adrenolytic medical therapy need to be carefully considered, ideally in a multidisciplinary setting. The management of Nelson's Syndrome often requires both transsphenoidal surgery and radio-therapy to gain disease control.

Increased pentose phosphate pathway flux after clinical traumatic brain injury: a [1,2-13C2]glucose labeling study in humans

Patients with traumatic brain injury (TBI) routinely exhibit cerebral glucose uptake in excess of that expected by the low levels of oxygen consumption and lactate production. This brings into question the metabolic fate of glucose. Prior studies have shown increased flux through the pentose phosphate cycle (PPC) during cellular stress. This study assessed the PPC after TBI in humans. [1,2-(13)C(2)]glucose was infused for 60 mins in six consented, severe-TBI patients (GCS<9) and six control subjects. Arterial and jugular bulb blood sampled during infusion was analyzed for (13)C-labeled isotopomers of lactate by gas chromatography/mass spectroscopy. The product of lactate concentration and fractional abundance of isotopomers was used to determine blood concentration of each isotopomer. The difference of jugular and arterial concentrations determined cerebral contribution. The formula PPC=(m1/m2)/(3+(m1/m2)) was used to calculate PPC flux relative to glycolysis. There was enrichment of [1,2-(13)C(2)]glucose in arterial-venous blood (enrichment averaged 16.6% in TBI subjects and 28.2% in controls) and incorporation of (13)C-label into lactate, showing metabolism of labeled substrate. The PPC was increased in TBI patients relative to controls (19.6 versus 6.9%, respectively; P=0.002) and was excellent for distinguishing the groups (AUC=0.944, P<0.0001). No correlations were found between PPC and other clinical parameters, although PPC was highest in patients studied within 48 h of injury (averaging 33% versus 13% in others; P=0.0006). This elevation in the PPC in the acute period after severe TBI likely represents a shunting of substrate into alternative biochemical pathways that may be critical for preventing secondary injury and initiating recovery.

Stereotactic radiation treatment for recurrent nonbenign meningiomas

Object

The authors analyzed the results of stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) for the treatment of recurrent meningiomas that were described at initial resection as showing aggressive, atypical, or malignant features (nonbenign).

Methods

Twenty-five patients who underwent SRS and/or SRT for nonbenign meningiomas between December 1992 and August 2004 were included. Thirteen of these patients underwent treatment for multiple primary or recurrent lesions. In all, 52 tumors were treated. All histological sections were reviewed and reclassified according to World Health Organization (WHO) 2000 guidelines as benign (Grade I), atypical (Grade II), or anaplastic (Grade III) meningiomas. The median follow-up period was 42 months.

Seventeen (68%) of the cases were reclassified as follows: WHO Grade I (five cases), Grade II (11 cases), and Grade III (one case). Malignant progression occurred in eight cases (32%) during the follow-up period; these cases were considered as a separate group. The 3-year progression-free survival (PFS) rates for the Grades I, II, and III, and malignant progression groups were 100, 83, 0, and 11%, respectively (p < 0.001). In the Grade II group, the 3-year PFS rates for patients treated with SRS and SRT were 100 and 33%, respectively (p = 0.1). After initial treatment, 22 new tumors required treatment using SRS or SRT; 17 (77%) of them occurred inside the original resection cavity. Symptomatic edema developed in one patient (4%).

Conclusions

Stereotactic radiation treatment provided effective local control of “aggressive” Grade I and Grade II meningiomas, whereas Grade III lesions were associated with poor outcome. The outcome of cases in the malignant progression group was intermediate between that of the Grade II and Grade III groups, with the lesions showing a tendency toward malignancy.

Avoidance of carotid artery injuries in transsphenoidal surgery with the Doppler probe and micro-hook blades

OBJECTIVE

Internal carotid artery (ICA) injury during sellar dural opening is a potentially catastrophic complication of transsphenoidal surgery. We describe two ICA injuries that occurred early in our endonasal transsphenoidal experience. We then describe our subsequent protocol to prevent this complication in which we use the Doppler probe for carotid localization and micro-hook blades for lateral dural opening.

METHODS

All patients undergoing endonasal tumor removal were analyzed since beginning this approach in 1998. Of 631 procedures (585 patients), three patients sustained an ICA injury.

RESULTS

In the first 114 procedures (105 patients) in which the Doppler probe was not used and hook blades were used infrequently, two (1.8%) ICA injuries occurred. In both cases, a right nostril approach was used and the left ICA was punctured on dural opening with a straight scalpel; both patients recovered without neurological sequelae. In the subsequent 517 procedures in which the Doppler probe and hook blades were used in all cases, one (0.19%) probable ICA injury occurred during an attempted removal of a cavernous sinus schwannoma, although there was no angiographic evidence of vascular injury. There were no ICA or other intracranial vascular injuries in the last 510 procedures for tumors not solely confined to the cavernous sinus.

CONCLUSION

Cavernous carotid localization with the Doppler probe before dural opening and angled hook blades for lateral dural opening can help minimize the risk of ICA injury and are recommended for all transsphenoidal operations. Because of the wider contralateral exposure provided by the endonasal approach, the ICA contralateral to the nostril of approach is at higher risk of injury on dural opening.

GRADED REPAIR OF CRANIAL BASE DEFECTS AND CEREBROSPINAL FLUID LEAKS IN TRANSSPHENOIDAL SURGERY

OBJECTIVE

A graded approach to cerebrospinal fluid (CSF) leak repair after transsphenoidal surgery is presented.

METHODS

Patients undergoing endonasal tumor removal during an 8-year period were reviewed. Intraoperative CSF leaks were classified as Grade 0, no leak observed; Grade 1, small leak without obvious diaphragmatic defect; Grade 2, moderate leak; or Grade 3, large diaphragmatic/dural defect. Cranial base repair was tailored to the leak grade as Grade 0, collagen sponge; Grade 1, two-layered collagen sponge repair with intrasellar titanium mesh buttress; Grade 2, intrasellar and sphenoid sinus fat grafts with collagen sponge overlay and titanium buttress; and Grade 3, same as Grade 2 with CSF diversion in most cases. A provocative tilt test was performed before patient discharge to assess the integrity of the CSF leak repair. Protocol modifications adopted in 2003 included an intrasellar fat graft in Grade 1 leaks with a large intrasellar dead space, frequent use of BioGlue (CryoLife, Inc., Atlanta, GA) in Grade 1, 2, and 3 leaks, and CSF diversion for all Grade 3 leaks.

RESULTS

Among 668 cases in 620 patients (475 pituitary adenomas and 145 other lesions), an intraoperative CSF leak was observed in 57% of the cases: 32.5% Grade 1, 15% Grade 2, and 8.7% Grade 3. Postoperative repair failures occurred in 17 cases (2.5%), including 0.7, 3, 1, and 12% of Grade 0, 1, 2, and 3 CSF leaks, respectively. Bacterial meningitis occurred in three patients (0.45%). After protocol modifications in 2003, repair failures decreased from 4 to 1.2% (P = 0.02).

CONCLUSION

A graded repair approach to CSF leaks in transsphenoidal surgery avoids tissue grafts and CSF diversion in more than 60% of patients. Protocol modifications adopted in the last 340 cases have reduced the failure rate to 1% overall and 7% for Grade 3 leaks. Provocative tilt testing before patient discharge is helpful in the timely diagnosis of postoperative CSF leaks.

Management of type 2 diabetes mellitus associated with pituitary gigantism

Pituitary gigantism, a condition of endogenous growth hormone (GH) hypersecretion prior to epiphyseal closure, is a rare condition. In the adult condition of GH excess, acromegaly, the occurrence of type 2 diabetes mellitus (T2DM) and diabetic ketoacidosis (DKA) have been reported, with resolution following normalization of GH levels. We report the case of a 16-year-old male with pituitary gigantism due to a large invasive suprasellar adenoma who presented with T2DM and DKA. Despite surgical de-bulking, radiotherapy and medical treatment with cabergoline and pegvisomant, GH and insulin-like growth factor-I (IGF-I) levels remained elevated. However, the T2DM and recurrent DKA were successfully managed with metformin and low-dose glargine insulin, respectively. We review the pathophysiology of T2DM and DKA in growth hormone excess and available treatment options.

BioGlue for prevention of postoperative cerebrospinal fluid leaks in transsphenoidal surgery: A case series

BACKGROUND

The efficacy of BioGlue (CryoLife, Inc, Atlanta, Ga) surgical adhesive in transsphenoidal surgery was assessed as an adjunct in the prevention of postoperative CSF leaks.

METHODS

All patients in whom BioGlue was used for an intraoperative skull base reconstruction were retrospectively identified. Intraoperative CSF leaks were graded according to size (grade 1, small weeping leak without obvious diaphragmatic defect; grade 2, moderate leak with a definite diaphragmatic defect; grade 3, large diaphragmatic and/or dural defect). CSF leak repair was tailored to CSF leak grade. BioGlue was applied as a reinforcement over collagen sponge as the last layer of the repair.

RESULTS

Over 28 months, a total of 282 patients underwent endonasal surgery. Of these patients, 124 (79 women; age range, 8-84 years), in 128 procedures, had an intraoperative CSF leak repair reinforced with BioGlue. Pathology included 80 pituitary adenomas, 11 craniopharyngiomas, 7 Rathke's cleft cysts, 6 chordomas, 5 meningiomas, 4 spontaneous CSF leaks, 3 arachnoid cysts, and 8 other parasellar pathologies. There were 62 (48.4%) grade 1, 41 (32.0%) grade 2, and 25 (19.5%) grade 3 leak repairs. The overall repair failure rate was 1.6% (2 cases), with the failures occurring in patients with grade 3 leaks, including 1 who developed meningitis; there was no failure of grades 1 and 2 leaks. The 2 failures were attributed largely to technical aspects of the repair rather than to failure of BioGlue per se.

CONCLUSIONS

BioGlue appears to be an effective adjunct in preventing postoperative CSF leaks after transsphenoidal surgery. However, careful attention to technical details of the repair is still required to prevent failures, especially when closing large dural and diaphragmatic defects.

Neurobehavioral and quality of life changes associated with growth hormone insufficiency after complicated mild, moderate, or severe traumatic brain injury

Adult-onset growth hormone deficiency (GHD) has been associated with reduced quality of life (QOL) and neurobehavioral (NB) deficits. This prospective study tested the hypothesis that traumatic brain injury (TBI) patients with GHD or GH insufficiency (GHI) would exhibit greater NB/QOL impairment than patients without GHD/GHI. Complicated mild, moderate, and severe adult TBI patients (GCS score 3-14) had pituitary function and NB/QOL testing performed 6-9 months postinjury. GH-secretory capacity was assessed with a GHRH-arginine stimulation test and GHD and GHI were defined as peak GH<6 or <or=12 ng/mL (5th and 10th percentiles of healthy control subjects, respectively). Of 44 patients (mean age, 32+/-18 years; median GCS, 7), one (2%) was GHD, seven (16%) were GHI, and 36 (82%) were GH-sufficient at 6-9 months post-injury. Mean peak GH was 8.2+/-2.1 ng/mL in the GHD/GHI group versus 45.7+/-29 ng/mL in the GHsufficient group. The two groups were well-matched in injury characteristics, except that one patient with GHD had central hypogonadism treated with testosterone prior to NB/QOL testing. At 6-9 months postinjury, patients with GHD/GHI had higher rates of at least one marker of depression (p<0.01), and reduced QOL (by SF-36 Health Survey) in the domains of limitations due to physical health (p=0.02), energy and fatigue (p=0.05), emotional well-being (p=0.02), pain (p=0.01), and general health (p=0.05). Chronic GHI develops in approximately 18% of patients with complicated mild, moderate, or severe TBI, and is associated with depression and diminished QOL. The impact of GH replacement therapy on NB function and QOL in these TBI patients is being tested in a randomized placebo-controlled trial.

Primary sphenoid sinus neoplasms: a report of four cases with common clinical presentation treated with transsphenoidal surgery and adjuvant therapies

BACKGROUND

Primary neoplasms of the sphenoid sinus are a rare occurrence, accounting for approximately 1-2% of all paranasal sinus tumors. Here we report a series of four such patients.

METHODS

Four patients with sphenoid sinus neoplasms were identified (1%), all treated during the year 2003.

RESULTS

The four patients included two women and two men (mean age 61 years, range 44-70 years). Two patients presented with unilateral abducens cranial nerve (CN) palsies; one had trigeminal facial numbness and dizziness; another had headache, epistaxis, and partial third and fourth CN palsies. MRIs in all patients demonstrated large sphenoid sinus masses with partial clival and sellar bone erosion but with clear visualization of the pituitary gland above the mass. Cavernous sinus invasion was present in all four cases, including one patient with tumor in the ethmoid sinus and intra-tumoral hemorrhage. No patients had endocrinopathy. All patients underwent subtotal tumor removal via an endonasal transsphenoidal route. Tumor histology included neuroendocrine carcinoma, sinonasal undifferentiated carcinoma, mucoepidermoid carcinoma, and giant cell tumor. Post-operatively, all four patients had improved symptoms with complete resolution of diplopia in 3 of 3 patients. Metastatic work-ups were negative in all patients, and all received fractionated stereotactic radiotherapy; three received chemotherapy. One patient required a second endonasal tumor debulking 15 months after the first for new visual loss that then resolved. At a median follow-up of 21 months, all patients are alive and functional.

CONCLUSIONS

Intra-sphenoidal tumors are locally invasive tumors that include a wide pathological spectrum. In this small series, they presented with cavernous sinus symptoms and headache but not endocrinopathy. Recognizing their distinctive clinical presentation and MRI features is helpful in differentiating them from primary sellar tumors. Their aggressive nature warrants a multimodality treatment plan including surgical debulking, radiotherapy, and chemotherapy in some cases.