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ORIGINAL ARTICLE
Year : 2015  |  Volume : 28  |  Issue : 1  |  Page : 87-92

Surgical outcome of endoscopic versus microscopic trans-sphenoidal approach for pituitary adenomas


1 Department of Neurosurgery, Faculty of Medicine, Menoufia, Menoufia, Egypt
2 Department Neurosurgery, Faculty of Medicine, Alexandria, Egypt

Date of Submission17-May-2014
Date of Acceptance07-Jul-2014
Date of Web Publication29-Apr-2015

Correspondence Address:
Mohamed Ahmed Aly Eltabl
Department of Neurosurgery, Faculty of Medicine, 18 Elmaamon Street, Shebien Elkom, Menoufia
Egypt
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1110-2098.155950

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  Abstract 

Objective
The aim of the study was to compare between endoscopic and microscopic trans-sphenoidal approach regarding surgical outcome and postoperative complications.
Background
Pituitary adenomas are the third most common intracranial tumors in surgical practice, accounting for ~10-25% of intracranial tumors. These tumors may gain large size before producing hormonal or visual symptoms. There are many surgical approaches for these tumors.
Patients and methods
Over the last 3 years, 40 patients with pituitary adenoma either microadenoma or macroadenoma were operated through trans-sphenoidal approach either microscopically or endoscopically. Patient consent was obtained followed by careful clinical history, symptoms, signs, and preoperative radiological evaluation. Operative and postoperative events were noted with 3 months follow-up.
Results
A total of 40 patients with pituitary adenomas were operated trans-sphenoidally. The mean age was 35.9 years (range 21-60 years). The number of men was 23 (57.5%) and women was 17 (42.5%). The most common presenting symptom was headache in 25 (62.5%) patients and visual complaints in 24 (60%) patients. Amenorrhea and acromegaly were in eight (20%) patients for each; Cushing syndrome was present in three (7.5%) patients. Hyperthyroidism and infertility were in two (5%) patients for each.
Conclusion
Surgical outcome in endoscopic trans-sphenoidal approach is better than microscopic approach regarding postoperative nasal complications.

Keywords: Adenoma, endoscope, microscope, pituitary, trans-sphenoidal


How to cite this article:
Eltabl MA, Eladawy YM, Hanafy AM, Gaber Saleh EE, Elnoomany HA. Surgical outcome of endoscopic versus microscopic trans-sphenoidal approach for pituitary adenomas. Menoufia Med J 2015;28:87-92

How to cite this URL:
Eltabl MA, Eladawy YM, Hanafy AM, Gaber Saleh EE, Elnoomany HA. Surgical outcome of endoscopic versus microscopic trans-sphenoidal approach for pituitary adenomas. Menoufia Med J [serial online] 2015 [cited 2024 Mar 29];28:87-92. Available from: http://www.mmj.eg.net/text.asp?2015/28/1/87/155950


  Introduction Top


Pituitary adenomas are the third most common intracranial tumors in surgical practice, accounting for ~10-25% of intracranial tumors. Pituitary tumors are frequently seen in autopsy specimens (14%). Furthermore, recent epidemiological data suggest that clinically apparent pituitary adenomas have a prevalence of ~1/1000 in the general population [1]. Although only very rarely malignant, pituitary tumors may cause significant morbidity in affected patients. First, given the critical location of the gland, large tumors may lead to mass effects and proliferation of hormone-secreting pituitary cells leads to endocrine syndromes. Approximately, 50% of newly diagnosed pituitary adenomas are prolactinomas. Nonfunctioning pituitary adenomas represent about 30%, somatotrophic adenomas 15-20%, corticotrophin adenomas 5-10%, and thyrotrophic adenomas less than 1%. The majority of pituitary adenomas are sporadic, although some arise as a component of familial syndromes. Visual disorders may develop due to compression on the visual pathway (bitemporal hemianopsia) [2]. Diagnosis of pituitary tumors is both clinical and radiological diagnosis. Secreting tumors are usually diagnosed by the endocrinologist, whereas the nonsecreting tumors by the ophthalmologists as they produce visual defects in the absence of any systemic signs [3]. We analyzed surgical outcome and postoperative complications of 25 patients with pituitary adenomas operated in Neurosurgical Department in Menoufia and Alexandria Universities between 2011 and 2013.


  Patients and methods Top


This study included 40 cases of pituitary adenomas operated upon during the period from 2011 to 2013. Twenty-five cases underwent endoscopic endonasal trans-sphenoidal surgery (group A), whereas the remaining 15 cases were operated upon using the standard microscopic trans-sphenoidal surgery (group B). Irregular, multilocular tumors or tumors with eccentric extensions into the frontal, temporal, or posterior fossae were not included in this study. This study was an observational study; both study groups were not similar with respect to age, sex, presenting symptoms, previous management, tumor type, shape or extensions, preoperative images, or hormonal profile. Selection between both groups (group A and B) and choice of the surgical approach was mainly based on referring surgeons' decision depending on their own surgical experience. Inclusion criteria of selected cases were to be pure sellar lesions or sellar lesions with only midline suprasellar extensions either solid or cystic; lesions with suprasellar extensions away from midline were not included.

Full neurological examination was performed including motor, sensory, autonomic, neurological reflexes, and cranial nerves examination. Routine and basic hormonal levels were performed. Computed tomography sella, MRI brain, and computed tomography paranasal sinuses were performed for every case. Surgery was indicated for patients who have lesions that are compressing optical pathway causing visual defects, lesions with endocrinopathies either with hypersecretion or hyposecretion with failure of medical treatment, or lesions that cause pituitary apoplexy where urgent surgical decompression was indicated. All patients in this study were hospitalized and prepared night before surgery with stress doses of steroids in the form of 100 mg of hydrocortisone at night before surgery and at morning of the day of surgery under a cover of suitable antibiotic.

Twenty-five patients were operated by endoscopic endonasal approach. In this study, Karl Storz telescope was used; the endoscope is a rigid scope 4 mm in diameter and 18 cm in length and with 0 and 30° lenses. The endoscope is connected to a cable, which is made of optical fibers capable of high-quality optical transmission. Patients were positioned under general anesthesia in a standard semirecumbent position (~20° back up) with the head placed in a horseshoe headrest and the head turned 10° toward the surgeon. Before beginning the surgical procedure, the anesthesiologist must ensure bloodless nasal cavities, by means of a slight controlled hypotension and excellent analgesia to minimize mucosal bleeding. The endoscope was introduced through the chosen nostril, tangential to the floor of the nasal cavity. The structures that were identified were the inferior turbinate laterally and the nasal septum medially. Above the inferior turbinate, the head of the middle turbinate can be observed; usually, it was close to the nasal septum. As the endoscope advanced along the floor of the nasal cavity, it reached the choana. Its medial margin was the vomer, which confirmed the midline of the approach. After the creation of adequate space between the middle turbinate and the nasal septum, the endoscope was angled upward along the roof of the turbinate and the sphenoethmoid recess until it reached the sphenoid ostium, usually located ~1.5 cm above the roof of the turbinate. A wide anterior sphenoidotomy was performed including and lateral to both sphenoid ostia. Superior limit allowed visualization of the planum sphenoidale, the optic protuberances, and the optic-carotid recesses. The images of the sphenoid sinus septae revealed by the preoperative computed tomography scan (in coronal and axial projections) must be compared with the endoscopic views. The sellar floor was opened to the limits of the cavernous sinus laterally, the tuberculum and planum superiorly, and the clival recess inferiorly. Dura is incised in a midline position and in a linear, rectangular, or cruciate manner. The removal of macroadenomas was accomplished sequentially. The inferior and lateral fragments of the lesion were removed before the superior aspect. Removal of the superior part of the macroadenoma first prematurely delivered the redundant diaphragma sellae into the operative field, which obscured visualization of the lateral portions and reduced the possibility of radical removal of the adenoma after the removal of the macroadenoma; if the descent of the suprasellar portion of the lesion is not observed, valsalva maneuver was performed to deliver the suprasellar cistern into the sellar cavity. During removal of microadenomas, the endoscope was put too close to the sellar cavity to obtain a closer view of the surgical field. Angled 30 and 45° endoscope were advanced sequentially into the tumor cavity to verify the presence of any tumor remnants. Sellar floor reconstruction represented an essential step in case of evident intraoperative cerebrospinal fluid (CSF) leak.

The remaining 15 cases were operated microscopically, which were nearly the same as the endoscopic one regarding patients positioning, nasal preparation, sphenoidal and sellar phases, also by the same principles in sellar reconstruction with a difference only in the nasal phase of the procedure. Endonasal approach was used in which the view of the microscope was directed through one nostril between the nasal septum and nasal conchae to the sphenoid face below the ostia without incision needed in the anterior part of the nasal cavity. Follow-up was analyzed for each patient; all specimens that were obtained were recorded in patients' file. Follow-up MRI brain was performed after 3 months until the fat that was used in reconstruction has been absorbed.


  Results Top


Results were collected, tabulated, and statistically analyzed by IBM personal computer and statistical package SPSS (version 20; SPSS Inc., Chicago, Illinois, USA). Two types of statistics were performed:

(1) Descriptive : for example, percentage, range, mean, SD, and range.

(2) Analytical :

(a) Student's t-test: it is a single test used to collectively indicate the presence of any significant difference between two groups for a normally distributed quantitative variable.

(b) c2 -Test: it is used to compare between two groups or more regarding one qualitative variable in 2 × 2 contingency table or r-c complex table.

(c) Fisher's exact test: it is used to compare between two groups regarding one qualitative variable in 2 × 2 contingency table when the count of any of the cells is less than 5.

(d) Z -test: it is used between two proportions.

P value less than 0.05 was considered significant; P value greater than 0.05 was considered nonsignificant; and P value less than 0.001 was considered highly significant.

The mean age was 35.9 years (range 21-60 years). The number of men was 23 (57.5%) and women was 17 (42.5%). The most common presenting symptom was headache in 25 (62.5%) patients and visual complaints in 24 (60%) patients. Amenorrhea and acromegaly were in eight (20%) patients for each; Cushing syndrome was present in three (7.5%) patients. Hyperthyroidism and infertility was in two (5%) patients for each.

Surgical indications had the following order in a decreasing manner: visual pathway decompression in 21 (52.5%) patients, failed medical treatment of amenorrhea in eight (20%) patients, decreasing acromegalic symptoms in six (15%) patients, decreasing symptoms of Cushing syndrome in five (12.5%) patients, and finally decreased hyperthyroidism manifestations in two (5%) patients. The mean operative time in endoscopic approach was 2.5 h and in microscopic approach was 2.43 h with no significant difference. Regarding intraoperative complications, there were no complications in 18 (72%) patients in endoscopic approach and 12 (80%) patients in microscopic approach. CSF leak was detected in six (24%) patients and anterior intercavernous sinus bleeding in one (4%) patient in endoscopic approach; in contrast, CSF leak was detected in two (13.3%) patients and intercavernous sinus bleeding in one (6.7%) patient in microscopic approach with no significant difference. In the endoscopic group, the most common pathologies were chromophobe adenomas in seven (28%) cases and prolactinomas in seven (28%) cases. In the other group, five (33.3%) cases had chromophobe adenomas and GH adenomas in five (33.3%) cases. The postoperative hormonal screening was observed in the endoscopic group, was normal in 21 (84%) patients, and decreased in two (8%) cases, preoperative in one case and increased in one case. In the microscopic group, postoperative hormonal screening was normal in 13 (86.7%) cases, decreased in one (6.7%) patient, and increased in one (6.7%) patient with no significant difference between two groups regarding the postoperative hormonal screening. In endoscopic approach, total removal was achieved in 20 (80%) cases and subtotal removal in five (20%) cases. In the microscopic group, total removal was achieved in 10 (66.7%) cases and subtotal removal in five (33.3%) cases with no significant difference. Regarding postoperative complications, nasal complications were zero in the endoscopic group and were 33.3% in the microscopic group with significant difference between them [Figure 1] and [Figure 2] and [Table 1],[Table 2],[Table 3],[Table 4],[Table 5] and [Table 6].
Table 1: Distribution of the studied patients regarding their age and sex

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Table 2: Distribution of the studied patients regarding their clinical pictures and hormonal screening

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Table 3: Distribution of the studied patients regarding their surgical approach

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Table 4: Distribution of the studied groups regarding operative time and interoperative complications

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Table 5: Distribution of the studied groups regarding postoperative MRI

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Table 6: Distribution of the studied groups regarding postoperative complications

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Figure 1: (a, b) T1 MRI brain with contrast sagittal and axial cuts. Preoperative nonfunctioning pituitary adenoma. (c, d) Postoperative MRI after 3 months.

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Figure 2: (a, b) T1 MRI brain with contrast sagittal and axial cuts. Preoperative prolactinoma. (c, d) Postoperative MRI after 3 months.

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  Discussion Top


Surgery for tumors of the pituitary gland still represents a significant challenge, despite the highly refined nature of the contemporary microsurgery; in and around the pituitary gland is an area of the brain studded with vital anatomical structures [4].

The endoscope has been introduced to trans-sphenoidal surgery and has gained significant popularity. Endoscope-assisted trans-sphenoidal operations refer to microscopic procedures in which the endoscope is used as an adjunct to the microscopic removal of a tumor. The manner in which the endoscope is used adjunctively, however, can vary significantly. The endoscope may simply be used to perform an anterior sphenoidotomy before inserting the nasal speculum and using the microscope. The endoscope may also be used during the microscopic tumor resection to inspect for areas of tumor residue out of the line of sight of the microscope. Pure endoscopic trans-sphenoidal surgery refers to the removal of tumors without the use of the operative microscope [5].

Although endoscope-assisted trans-sphenoidal approaches had been reported, the pure endoscopic trans-sphenoidal approach was introduced and popularized in the late 1990s by Jho and Carrau from the University of Pittsburgh Medical Center. Advances in endoscopic endonasal neurosurgical techniques at Pittsburgh continue in the work of Kassam and Carrau, who have expanded the scope of complex skull base tumors accessible by the endoscope. In Europe, the neurosurgical groups of Cappabianca, de Divitiis, and Frank have also made important contributions [6].

Our study included 40 patients of sellar lesions operated during the period between 2011 and 2013 in Menoufia and Alexandria University Hospitals; 25 patients underwent endoscopic endonasal trans-sphenoidal approach and 15 patients underwent microscopic trans-sphenoidal approach. This study was observational study; both groups were not similar with respect to age, sex, presenting symptoms, previous management, tumor type, shape or extensions, preoperative images, or hormonal profile. Selection between both groups and choice of the surgical approach were mainly based on referring surgeons' decision depending on their own surgical experience.

The highest age incidence of our cases was during the third and fourth decades of life, with a mean 35.9 years, which was coincident with the study by Shen et al. [7] who had 36.4 years as a mean of age. Men represented about 57.5% and women represented about 42.5%.

Headache was the most presenting symptoms in this study for both microscopic and endoscopic groups (62.5%), which was coincident with the study by Zhang et al. [8] and by Jackson et al. [2] who had 59 and 61.5% visual complaints, respectively, in their studies. Visual complaints were represented in 60% of the patients, which was coincident with the study by Jackson et al. [2] who found about 62% of his patients was complaining of headache.

Regarding operative time, 2.5 h was the mean in the endoscopic approach, whereas it was 2.43 h in the microscopic approach, which represented no significance between these approaches in contrast to the study by Federico et al. [9] who reported that endoscopic microsurgery offered a significantly shorter operative time (2.7 h in endoscopic surgery vs. 3.4 h in traditional sublabial microsurgery) without compromising the extent of tumor resection.

At the beginning of this study, the mean operative time was the same for both procedures. However, as the surgeons gained experience with endoscope, the operative time shortened, perhaps because there were fewer surgical complications and less need for wound packing and wound management and patients were more comfortable after the endonasal approach, the same like the study by Federico et al. [9] who had proposed the same evidence.

Throughout this study, complications associated with endoscopic surgery were, in general, fewer than with microsurgery, as there was less wound trauma with the endoscopic approach resulting in less nasal and orodental complications. No patients had nasal septum perforation, sinusitis, and gum wound disruption or massive nasal bleeding [10]. Reported that 90% of patients with endoscopically removed prolactinomas were satisfied with their nasal airways postoperatively, they had no operative infections. In contrast, there were five (33.3%) patients who had nasal complications with P-value of 0.009, which is highly significant difference. Improved visualization allowed the surgeon to identify and avoid injury to the normal pituitary, carotid prominences, hypothalamus, and optic chiasm leading to fewer complications with better outcome. The incidence of sinusitis was higher in the microscopic group, because the trauma to the sphenoid sinus and nasal cavity is greater as reported in the study by {21}.

In the endoscopic group, the most common pathologies were chromophobe adenomas in seven (28%) cases and prolactinomas in seven (28%) cases. In the microscopic group, five (33.3%) cases had chromophobe adenomas and GH adenomas in five (33.3%) cases.

Regarding the radicality of the excision, in endoscope approach, total removal was achieved in 20 (80%) cases and subtotal removal in five (20%) cases. In the microscopic group, total removal was achieved in 10 (66.7%) cases and subtotal removal in five (33.3%) cases with no significant difference as reported in the study by Micah et al. [11]. Of the patients with subtotal removal, half of them had medical treatment in the form of dopamine agonists and the rest were followed up clinically and radiologically. The residual was present lateral and suprasellar. Vigorous manipulation was not performed for fear of injury to diaphragm sellae superiorly or to the cavernous sinus laterally.

Regarding visual and hormonal symptoms, clinical improvement as improvement of vision was achieved in 81.2% and the rest improved but did not reach the normal visual acuity; in contrast, there was 62.5% improvement in microscopic cases and the remainder also did not reach the normal level of visual acuity with no significant difference between two groups regarding clinical improvement of vision. The postoperative hormonal screening in the endoscopic group was normal in 21 (84%) patients and decreased in two (8%) cases, preoperative in one case and increased in one case. In the microscopic group, postoperative hormonal screening was normal in 13 (86.7%) cases, decreased in one (6.7%) patient, and increased in one (6.7%) patient with no significant difference between two groups regarding the postoperative hormonal screening. These results are in agreements with that of Jackson et al. [2] and Shahinian et al. [12] who studied postoperative visual state and postoperative hormonal screening.

Regarding postoperative complications, nasal complications were zero in the endoscopic group and were 33.3% in the microscopic group with significant difference between them.

Postoperative CSF leak was noticed in four (16%) cases of endoscopically operated patients and in one (6.7%) case in the microscopic group with no significant difference between both groups, similar to the study by Zhang et al. [8]. Of these five cases with postoperative CSF leak, the leak has been stopped in three cases with bed rest and carbonic anhydrase inhibitors and two cases needed lumbar drain for 5 days before stoppage of the leak.


  Conclusion Top


Surgical outcome in endoscopic trans-sphenoidal approach is better than microscopic approach regarding postoperative nasal complications.


  Acknowledgements Top


Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Schwartz TH, Stieg PE, Anand VK, et al. Endoscopic trans-sphenoidal pituitary surgery with intraoperative magnetic resonance imaging. Neurosurgery 2006; 58 :44-51.  Back to cited text no. 1
    
2.
Jackson A, Schops M, Joao C, et al. Endoscopic endonasal trans-sphenoidal surgery: surgical results of 228 pituitary adenomas treated in a pituitary center. Pituitary 2010; 13 : 68-77.  Back to cited text no. 2
    
3.
Patel ZM, Gupta SS. Imaging in common anterior and sellar/perisellar skull base lesions. Otorhinolaryngol Clin 2011; 3 :135-150.  Back to cited text no. 3
    
4.
Edjah K, Emily M, Zara M, et al. Transnasal approaches to the sellar and parasellar region: open and endoscopic. Oper Tech Otolaryngol Head Neck Surg 2013; 24 :208-212.  Back to cited text no. 4
    
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Sethi DS, Leong JL. Endoscopic pituitary surgery. Otolaryngol Clin North Am 2006; 39 :563-583.  Back to cited text no. 5
    
6.
Kassam A, Snyderman CH, Int A, et al. Expanded endonasal approach: the rostrocaudal axis: Part II. Posterior clinoids to the foramen magnum. Neurosurg Focus 2005; 19 :321-339.  Back to cited text no. 6
    
7.
Shen CC, Wang YC, Hua WS, et al. Endoscopic endonasal trans-sphenoidal surgery for pituitary tumors. Chin Med J 2000; 63 :301-310.  Back to cited text no. 7
    
8.
Zhang X, Fei Z, Zhang W, et al. Endoscopic endonasal trans-sphenoidal surgery for invasive pituitary adenoma. J Clin Neurosci 2008; 15 :241-245.  Back to cited text no. 8
    
9.
Federico R, Marco F, Ilaria B, et al. Adenomas of the pituitary gland diagnostic challenges, pitfalls and controversies: mini-symposium. Neurooncology 2011; 76 :476-485.  Back to cited text no. 9
    
10.
Irene H, Rosa C, Marta G, et al. Clinical guidelines for diagnosis and treatment of prolactinoma and hyperprolactinemia. Endocrinol Nutr 2013; 60 :308-319.  Back to cited text no. 10
    
11.
Micah Hi, Rakesh K, Andrew J, et al. Endoscopic trans-sphenoidal approaches to the sella. Oper Tech Otolaryngol 2010; 21 :51-55.  Back to cited text no. 11
    
12.
Shahinian UK, Eby JB, Cha T, et al. Fully endoscopic endonasal vs. transseptal trans-sphenoidal pituitary surgery. Minim Invasive Neurosurg 2005; 48 :348-354.  Back to cited text no. 12
    


    Figures

  [Figure 1], [Figure 2]
 
 
    Tables

  [Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6]


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