INTRODUCTION

 

Sellar and parasellar regions with its  suprasellar extension are very important areas within the intra cranial cavity that has many important structures¹, such structures like pituitary adenoma, pituitary stalk, hypothalamus, both optic nerves, optic chiasm and many vascular structures like anterior circulation and cavernous sinus², contents of cavernous sinus such as intracavernous portion of carotid artery, venous network, and cranial nerves III, IV, VI that mainly controlling eye movments³, it extend inferiorly to base of sphenoid sinus laterally to cavernous sinus and superiorly to ventricular walls⁴, many lesions can affect these areas such as pituitary adenoma, meningioma, craniopharyngioma, and epidermoid, arachnoid cysts and vascular lesions like aneurysms of anterior circulation². Symptoms and signs of patients with these lesions varying from accidentally discovered, headache, hormonal imbalance, visual affection, proptosis and cranial nerve affection with intracavernous extension.¹

 

Many diagnostic investigations are very crucial to reach proper diagnosis for proper management such radiological investigations in form of CAT scan (CT) of brain, magnetic resonance imaging (MRI) and 4 vessels angiography or CT angiography to rule out relations of such lesions and vascular tree, hormonal profile is very important for replacement therapy pre and post operative⁵, visual impairment should be carefully investigated by clinical assessment, perimetry and fluorescein retinal angiography¹, deterioration of visual acuity is one of serious complications for these lesions that has to be treated rapidly to preserve visual function⁵, many surgical approaches are available for surgical decompression of lesions in these areas like transcranial, microscopic and or endoscopic transsphenoid corridor³

This study aims to outlines postoperative visual acuity in cases of sellar and suprasellar tumors and impact of safe surgical resection on the patients visual prognosis.

 

PATIENTS AND METHODS

 

Fifty cases with sellar and suprasellar tumors were included in this study. There were 28 females and 22 males. The age ranged from 31y to 55 years. All cases operated at Kasr El Aini Neurosurgical department from June 2011 to February 2014.

All patients had history, clinical examination, hormonal profile and radiological investigations in the form of CT scan, MRI and four vessels angiography, when needed, to outline relation between tumors and vascular tree, the cases suffered from any local eye disease were excluded from this study. All patients had visual acuity assessment using visual Lamdolt broken ring chart pre-operatively (Table 1) and 48 hrs and four months after surgery (Table 2).

Thirty patients were operated by microscopic assisted endoscopic endonasal transsphenoid approach for better visualization of optic apparatus postoperatively and20 cases operated by transcranial approach (12 cases by pterional approach and 8 cases by subfrontal approach). All cases had CT scan with sellar cuts and pituitary hormonal assessment on the second postoperative day. The visual acuity was assessed and recorded 48 hours and 4 months after surgery.

Forty cases were discharged within 5 days post operative. Seven cases were discharged 10 days after surgery due to postoperative Diabetes insipidus. The last 3 cases were discharged after 2 weeks due to chest infection.

 

RESULTS

 

Forty-three cases were operated by near total excision and seven cases were operated by subtotal excision being adherent to vital structure. Twenty-five cases were pituitary adenoma, 17 cases were craniopharyngioma (Figure 1), and eight cases were Meningioma. Postoperative results were obtained by visual assessment using Lamdolt broken ring chart 48hrs after operation and 4months later. 30 patients were operated by microscopic endonasal transsphenoid approach and 20 cases operated by transcranial approach.

Of the seven cases subtotal excision, three cases were craniopharyngioma, two cases were pituitary adenoma and two cases were meningioma. In the two meningioma cases subtotally excised, the visual acuity improved. In the three craniopharyngioma cases, two cases showed deterioration (no PL) in Rt. eye only and third had VA improvement. Two cases of pituitary adenoma, with subtotal resection, had same pre and postoperative visual acuity.

Thirty-two cases showed visual improvement by two lines in the Lamdolt broken ring chart 48hrs after surgery (8 meningioma, 18 pituitary adenoma, and 6 craniopharyngioma). Sixteen cases had same preoperative VA (10 cases of them improved gradually within 4 m (4 pituitary and 6 craniopharyngioma) and six cases were HM pre and post-operative (three pituitary adenoma and three craniopharyngioma). The VA was hand movement in two cases in right eye only and became no PL postoperative. These two cases were pathologically proven to have craniopharyngioma. After 4 months, 42 case showed improvement (84%),6 cases still had same pre and postoperative VA (12%) and only 2 cases (4%) had post operative visual acuity deterioration (Tables 1 and 2).

Forty-eight patients had an uneventful surgery. These cases have their vision improved or remained as pre-operative. In the last two cases (craniopharyngioma), the tumor was large and adherent to the surrounding. It compressed the optic pathway thus affecting the visual acuity preoperative to HM, an attempt was made to separate the tumor from the optic apparatus. This attempt ended in injury of the optic pathway and deterioration of vision.

 

 

 

Figure 1. A case of  48yrs old male with suprasellar craniopharyngioma showing pre (a) and post (b) operative images.

 

 

 

Table 1. Showing pre operative visual acuity in both eyes

 

Visual acuity	Rt .	Lt.
6/18	30	25
6/36	0	5
6/60	12	20
HM	8	0

 

Table 2. Showing postoperative visual acuity in both eyes4 months after surgery.

 

Visual acuity	Rt.	Lt.
6/6	5	5
6/9	20	20
6/18	17	22
6/36	0	3
HM	6	0
No PL	2	0

 

 

DISCUSSION

 

Sellar and suprasellar region has an intimate relation to many vital structures like vessels, hypothalamus, Pituitary gland and stalk, cranial nerves, cavernous sinus and optic apparatus. Such delicate structures make surgery in this area difficult and very challenging. Good anesthesia, proper instruments and safe careful surgery without severely damaged optic apparatus had a good impact on postoperative results especially on VA. Data from cancer registries suggest that prevalence of primary central nervous system (CNS) tumors is 130–230 cases per 100,000 of the population⁶. Lesions of the sellar and suprasellar region are very common, accounting for 10–15% of intracranial masses⁷.

In this series of fifty cases of suprasellar tumors, 84% had postoperative improvement of VA, 12% had same pre and postoperative VA, and finally 4% had postoperative deterioration of VA (no PL). In the deteriorated cases, the tumor was large craniopharyngioma adherent to the surrounding. It compressed the optic pathway thus affecting the visual acuity to HM. An attempt was made to separate the tumor from the optic apparatus, this attempt ended in injury of the optic pathway and deterioration of vision.

This results correlates with Koutourousiou et al.⁸. In their series in 2014, they documented good postoperative VA in 75 cases of suprasellar meningioma treated by endoscopic endonasal surgery. They had only two cases of visual acuity deterioration. However, their tumor pathology differs from this study where craniopharyngioma and pituitary adenoma were also included. The eight cases of meningioma, in this study, were operated upon transcranially. The all improved. This may be attributed to better visualization of optic nerve during the transcranial approach. However eight cases is a small number and further study should be done to draw a conclusion.

The result, in this study, is quiet similar with Sinha et al.⁹. They reported 70% improvement of VA of intrancranially treated 48 cases of suprasellar tumors. This study reported 20 cases of sellar, suprasellar tumors operated transcranially with 75%improvement in visual acuity. This slight difference may be attributed to the difference in tumor pathology. Han et al.¹⁰, also reported 82% improvement of postoperative VA in 29 patients with large suprasellar craniopharyngioma treated transcranially. This study reported 17 cases of craniopharyngioma (12 cases treated transcranial and 5 cases transsphenoid) with 70% postoperative improvement.

 

Conclusion

Safe, careful surgery of tumor in sellar and suprasellar regions with good instruments and anesthesia and without severely affected optic nerve can improve visual acuity.

 

[Disclosure: Authors report no conflict of interest]

 

REFERENCES

 

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