tuberculum sellae meningiomas ( tsms ) present a special symptom because of the adherence and compression to the optic nerve , optic artery , and the chiasm . a significant number of patients with tsms appear visual deficits . in recent articles , the optic canal involvement ( oci ) sade and lee reported that oci is very common in tsm ( 77.4% ) , and it correlates well with preoperative visual status . in this study , we intended to find another visual prognostic factor of tsm by comparing the blood flow of central retina artery ( cra ) pre- and post - operatively , and following up the outcomes of optic nerve decompression in tsm cases . totally 21 patients with tsm , who were operated from september 2007 to august 2011 in the department of neurosurgery , tongren hospital were retrospectively analyzed . all the 21 patients were followed up from 4 to 46 months ( 14.9 months in average ) . they were evaluated by neuro - ophthalmologists and radiologists before the operation to determine whether the tumors invaded into the optic canal and to predict the location of oci . characteristics of patients with tuberculum sellae meningiomas in this study nlp : no light perception ; lp : light perception ; hm : hand moving ; cf : counting fingers ; oci column : 1  positive ; hyperostosis of oc : 1  positive , 0  negative ; visual outcome : 1  increased , 0  unchanged , 1  deteriorated ; oci : optical canal involvement ; oc : optical canal ; od : right eye ; os : left eye . all of the patients had performed the following examination preoperatively including : orbital computed tomography ( ct ) and magnetic resonance imaging ( mri ) , visual acuity , goldmann visual field test , orbital color doppler flow imaging ( cdi ) test ( cra ; peak systolic velocity [ psv ] value ) . all of the patients had orbital ct and mri , and visual acuity test postoperatively . only 12 patients had visual field tests , and 10 patients had cdi test after surgery because the patients were treated by different doctors . the sub - frontal or sub - frontal temporal craniotomies were performed in this study . if the tumor was smaller than 2 cm in diameter , sub - frontal approach was performed ; if the tumor was larger than 2 cm in diameter , sub - frontal temporal approach was required to gain more space to obtain better exposure of the tumor . after craniotomy , we decompressed the optic roof from the epidural space , and then the optic nerve was explored and the tumor was resected subdural . if the patient had big frontal and sphenoidal sinus , the main concern of postoperative complication was cerebrospinal fluid ( csf ) leakage . we performed multi - layer hard dural reconstruction : the artificial cerebral dura mater patch was in the bottom , free temporal myofascial flap was on the dura mater patch and water - tight sutured with hard dura , and the pedicled galea flap was on the top . if the patient still had csf leakage postoperatively , then lumbar drainage was performed for a week , and the csf leakage was recovered . in this study , only 5 patients had transient csf leakage . three of them recovered by keeping lying in bed for 5 days , and 2 of them recovered by 7 days of continuous lumbar drainage . visual acuity and field outcomes were assessed separately , and improvement in one of these evaluations was necessary to qualify as a visual improvement . the preoperative orbital cdi tests ( psv values of cra ) were compared with visual outcomes [ tables 2 and 3 ] . preoperative cra orbital cdi test and visual outcome of patients in this study visual outcome : 1  increased , 0  unchanged , 1  deteriorated . cra : central retinal artery ; cdi : color doppler flow imaging ; psv : peak systolic velocity , od : right eye ; os : left eye . visual outcomes of patients in this study ( n ) cra : central retina artery ; psv : peak systolic velocity . values were analyzed using the chi - square test with spss for windows , release 11.5.0 ( spss inc . totally 21 patients with tsm , who were operated from september 2007 to august 2011 in the department of neurosurgery , tongren hospital were retrospectively analyzed . all the 21 patients were followed up from 4 to 46 months ( 14.9 months in average ) . they were evaluated by neuro - ophthalmologists and radiologists before the operation to determine whether the tumors invaded into the optic canal and to predict the location of oci . characteristics of patients with tuberculum sellae meningiomas in this study nlp : no light perception ; lp : light perception ; hm : hand moving ; cf : counting fingers ; oci column : 1  positive ; hyperostosis of oc : 1  positive , 0  negative ; visual outcome : 1  increased , 0  unchanged , 1  deteriorated ; oci : optical canal involvement ; oc : optical canal ; od : right eye ; os : left eye . all of the patients had performed the following examination preoperatively including : orbital computed tomography ( ct ) and magnetic resonance imaging ( mri ) , visual acuity , goldmann visual field test , orbital color doppler flow imaging ( cdi ) test ( cra ; peak systolic velocity [ psv ] value ) . all of the patients had orbital ct and mri , and visual acuity test postoperatively . only 12 patients had visual field tests , and 10 patients had cdi test after surgery because the patients were treated by different doctors . the sub - frontal or sub - frontal temporal craniotomies were performed in this study . if the tumor was smaller than 2 cm in diameter , sub - frontal approach was performed ; if the tumor was larger than 2 cm in diameter , sub - frontal temporal approach was required to gain more space to obtain better exposure of the tumor . after craniotomy , we decompressed the optic roof from the epidural space , and then the optic nerve was explored and the tumor was resected subdural . if the patient had big frontal and sphenoidal sinus , the main concern of postoperative complication was cerebrospinal fluid ( csf ) leakage . we performed multi - layer hard dural reconstruction : the artificial cerebral dura mater patch was in the bottom , free temporal myofascial flap was on the dura mater patch and water - tight sutured with hard dura , and the pedicled galea flap was on the top . if the patient still had csf leakage postoperatively , then lumbar drainage was performed for a week , and the csf leakage was recovered . in this study , only 5 patients had transient csf leakage . three of them recovered by keeping lying in bed for 5 days , and 2 of them recovered by 7 days of continuous lumbar drainage . visual acuity and field outcomes were assessed separately , and improvement in one of these evaluations was necessary to qualify as a visual improvement . the preoperative orbital cdi tests ( psv values of cra ) were compared with visual outcomes [ tables 2 and 3 ] . preoperative cra orbital cdi test and visual outcome of patients in this study visual outcome : 1  increased , 0  unchanged , 1  deteriorated . cra : central retinal artery ; cdi : color doppler flow imaging ; psv : peak systolic velocity , od : right eye ; os : left eye . visual outcomes of patients in this study ( n ) cra : central retina artery ; psv : peak systolic velocity . values were analyzed using the chi - square test with spss for windows , release 11.5.0 ( spss inc . , fourteen patients had bone proliferation within the area of the optic canal [ figure 1 ] . visual deficit and after the operation , visual outcomes were improved in 13 patients , unchanged in 7 patients and deteriorated in 1 patient . the optic canal computed tomography scan : preoperative axial ( a ) and coronal ( b ) positions . the orbital magnetic resonance imaging scan : t1 axial ( a ) , t1 axial with contrast ( b ) , t2 axial ( c ) , t1 coronal with contrast ( d ) . the green arrow indicated proliferation bone was resected ; ( b ) showed the subdural scene of operation . indicated optic canal involvement tumor ; black arrow indicated the optical canal segment of optic nerve , which was compressing by the optic canal involvement tumor from the lower and inner side ; the black triangles indicated the edge of optic nerve sheath , which was cut open . we compared the cra result as a variable in the visual outcome , the results showed that when the psv value of cra was 8 cm / s , the visual outcome was better than when psv value of cra was > 8 cm / s ( p = 0.024 ) . among 19 of 21 patients whose visual acuity was below 0.1 in at least one eye preoperatively , visual outcomes were improved in 13 patients , unchanged in 5 , and deteriorated in 1 postoperatively . preoperative visual acuity was not statistically related with the postoperative visual outcome ( p = 0.133 ) [ table 3 ] . in this study , 21 patients with tsms had extension into the optic canal ; those were confirmed by the operation . among the 21 patients , 14 patients had bone proliferation in the optic canal area . oci may be appreciated in preoperative mri , and optic canal ct scan could also find the hyperosteogeny of the optic canal . meningioma tends to affect the bone to be grown where it is located . the optic canal could be narrowed because of the pathological growth of the great wing of sphenoid . arai et al . emphasized that the presence of preoperative visual disturbance implies the need for optic canal unroofing . if oci was suspected in tsm , the optic canal exploration and decompression should be done during the operation . puchner et al . emphasized the need to remove tumor growth in the medial aspect of the optic canal to achieve the best long - term visual results up to the time of their report . depending on the extent and exact localization of the tumor origin , the bony origin was also drilled , and blood supply to the tumor via basal bony structures was interrupted to the extent possible without undue retraction of dural structures . the missing of oci in tsm may result in unimproved or deteriorated postoperative vision , and/or higher recurrence of the tumor and the simpson grade i or ii resection will not be achieved . tsms can extend into the optic canal unilaterally or bilaterally . in al - mefty 's series , 13 cases of bilateral oci were reported in among 45 patients who were found with anterior and middle fossa meningioma . in this group of patients , we preferred to do the boney decompression and exploring of the optic canal at the lower visual acuity side . in this study , we found 100% of cases with oci , and the difference between unilateral and bilateral oci was not discussed . while the number of patients was increasing , there might be new findings of oci in tsms . cdi to evaluate the hemodynamics of the orbital vasculature has been in use since the early 1990s . it has proved useful in the assessment of a number of orbital and ophthalmic disorders , including carotid cavernous fistula , orbital tumors , thyroid eye disease , vascular lesions ( such as occlusive vasculopathy of the retina and ischemic lesions of the optic nerve head and orbit ) and glaucoma . psv of cra shows the blood flow status of cra , which indicates the blood supply of retina . in the oci cases of tsms , the tumor encasement of optic nerve might decrease the psv of cra during the cdi test , which might be one of the reasons of visual deterioration . study of kahn showed the minimized value of normal psv of cra in cdi was about 8 cm / s . especially in the study of kahn , in which they collected 90 cases of healthy taiwanese . the mean psv of cra was 12.48  4.03 cm / s . in our study , we compared the visual outcome between the groups , one of which psv of cra was lower than 8 cm / s , and the other , higher than 8 cm / s . we found that , before the operation , if the psv value of cra was 8 cm / s , the visual outcome after surgery was more likely improved ( p = 0.024 , table 3 ) . the abnormal low psv value of cra indicated poor blood supply of optic nerve and retina . in the low psv of cra cases , poor blood supply might be the main reason of visual deterioration . and after decompressing the optic nerve , the blood supply was getting better , and the visual outcome might be improved . in previously published literatures the timing of optic canal decompression is still a subject of debate . in this study , we thought preoperative psv of cra 8 cm / s was another enhancing indication of exploring optic canal . previous articles reported that preoperative visual functions , duration of visual deterioration before surgery , and tumor size were factors influencing postoperative visual functions . reported in their study , which had 50 cases of parasellar meningiomas involving optic nerves ( including 16 tsms ) , visual outcomes were influenced by preoperative visual function , tumor size , and optic nerve encasement . one of the reasons is that our hospital is the biggest ophthalmology center in north china , and most patients come here with a chief complain of visual deterioration . we compared the visual outcome between the groups which preoperative had visual acuity higher than 0.1 and lower than 0.1 in snellen notation . after statistical analysis , it turned out that the preoperative visual acuity was not related to the visual outcome after surgery ( p = 0.133 , table 3 ) . but , the study of nozaki et al . drew the same conclusion . from another point of view , the small number of tsm patients without visual deterioration in our study might affect the statistic result . in 1945 , his dynamic vision checking method by hand , which could measure the difference of retinal light sensitivity , is still valuable in the clinical application . most of the patients had goldmann visual field test before the operation in this study . and the result of the visual field test identified the tumor location and direction of oci . because of the visual field and retina have an inverted and reversed relationship , as figure 4 was shown , the visual field test showed us the upper and outer visual field deficit of right eye , and this indicated that the optic nerve was compressing from the lower and inner direction around the optic canal area [ figure 3b ] . it was confirmed by ct and mri scans [ figures 1 and 2 ] . by using this evaluation , we could predict the location of the tumor within the optic canal , and cut it on purpose . the preoperative goldmann visual field test : left side ( a ) was normal , right side ( b ) was a deficit in upper and outer visual field . in conclusion , the surgical indications of exploring optic canal in tsm cases included : ( 1 ) neuroimaging evidences of oci ( ct and/or mri ) ; ( 2 ) psv of cra in orbital cdi test was 8 cm / s ; ( 3 ) visual acuity was below 0.1 ; ( 4 ) visual field deficit . exploring optic canal was the skull base technique which could accomplish simpson i level resection in this area . through this a visual field test was also an indication of oci location , and also guidance for the operation . in this study , 21 patients with tsms had extension into the optic canal ; those were confirmed by the operation . among the 21 patients , 14 patients had bone proliferation in the optic canal area . oci may be appreciated in preoperative mri , and optic canal ct scan could also find the hyperosteogeny of the optic canal . meningioma tends to affect the bone to be grown where it is located . the optic canal could be narrowed because of the pathological growth of the great wing of sphenoid . arai et al . emphasized that the presence of preoperative visual disturbance implies the need for optic canal unroofing . if oci was suspected in tsm , the optic canal exploration and decompression should be done during the operation . puchner et al . emphasized the need to remove tumor growth in the medial aspect of the optic canal to achieve the best long - term visual results up to the time of their report . depending on the extent and exact localization of the tumor origin , the bony origin was also drilled , and blood supply to the tumor via basal bony structures was interrupted to the extent possible without undue retraction of dural structures . the missing of oci in tsm may result in unimproved or deteriorated postoperative vision , and/or higher recurrence of the tumor and the simpson grade i or ii resection will not be achieved . tsms can extend into the optic canal unilaterally or bilaterally . in al - mefty 's series , 13 cases of bilateral oci were reported in among 45 patients who were found with anterior and middle fossa meningioma . in this group of patients , we preferred to do the boney decompression and exploring of the optic canal at the lower visual acuity side . in this study , we found 100% of cases with oci , and the difference between unilateral and bilateral oci was not discussed . while the number of patients was increasing , there might be new findings of oci in tsms . cdi to evaluate the hemodynamics of the orbital vasculature has been in use since the early 1990s . it has proved useful in the assessment of a number of orbital and ophthalmic disorders , including carotid cavernous fistula , orbital tumors , thyroid eye disease , vascular lesions ( such as occlusive vasculopathy of the retina and ischemic lesions of the optic nerve head and orbit ) and glaucoma . psv of cra shows the blood flow status of cra , which indicates the blood supply of retina . in the oci cases of tsms , the tumor encasement of optic nerve might decrease the psv of cra during the cdi test , which might be one of the reasons of visual deterioration . study of kahn showed the minimized value of normal psv of cra in cdi was about 8 cm / s . especially in the study of kahn , the mean psv of cra was 12.48  4.03 cm / s . in our study , we compared the visual outcome between the groups , one of which psv of cra was lower than 8 cm / s , and the other , higher than 8 cm / s . we found that , before the operation , if the psv value of cra was 8 cm / s , the visual outcome after surgery was more likely improved ( p = 0.024 , table 3 ) . the abnormal low psv value of cra indicated poor blood supply of optic nerve and retina . in the low psv of cra cases , poor blood supply might be the main reason of visual deterioration . and after decompressing the optic nerve , the blood supply was getting better , and the visual outcome might be improved . in previously published literatures the timing of optic canal decompression is still a subject of debate . in this study , we thought preoperative psv of cra 8 cm / s was another enhancing indication of exploring optic canal . previous articles reported that preoperative visual functions , duration of visual deterioration before surgery , and tumor size were factors influencing postoperative visual functions . reported in their study , which had 50 cases of parasellar meningiomas involving optic nerves ( including 16 tsms ) , visual outcomes were influenced by preoperative visual function , tumor size , and optic nerve encasement . one of the reasons is that our hospital is the biggest ophthalmology center in north china , and most patients come here with a chief complain of visual deterioration . we compared the visual outcome between the groups which preoperative had visual acuity higher than 0.1 and lower than 0.1 in snellen notation . after statistical analysis , it turned out that the preoperative visual acuity was not related to the visual outcome after surgery ( p = 0.133 , table 3 ) . but , the study of nozaki et al . drew the same conclusion . from another point of view , the small number of tsm patients without visual deterioration in our study might affect the statistic result . his dynamic vision checking method by hand , which could measure the difference of retinal light sensitivity , is still valuable in the clinical application . most of the patients had goldmann visual field test before the operation in this study . and the result of the visual field test identified the tumor location and direction of oci . because of the visual field and retina have an inverted and reversed relationship , as figure 4 was shown , the visual field test showed us the upper and outer visual field deficit of right eye , and this indicated that the optic nerve was compressing from the lower and inner direction around the optic canal area [ figure 3b ] . it was confirmed by ct and mri scans [ figures 1 and 2 ] . by using this evaluation , we could predict the location of the tumor within the optic canal , and cut it on purpose . the preoperative goldmann visual field test : left side ( a ) was normal , right side ( b ) was a deficit in upper and outer visual field . in conclusion , the surgical indications of exploring optic canal in tsm cases included : ( 1 ) neuroimaging evidences of oci ( ct and/or mri ) ; ( 2 ) psv of cra in orbital cdi test was 8 cm / s ; ( 3 ) visual acuity was below 0.1 ; ( 4 ) visual field deficit . exploring optic canal was the skull base technique which could accomplish simpson i level resection in this area . through this , the recurrence rate decreased , and the visual outcome was becoming better . a visual field test was also an indication of oci location , and also guidance for the operation .
background : tuberculum sellae meningiomas ( tsms ) present a special symptom because of the adherence and compression to the optic nerve , optic artery , and the chiasm . 
 a significant number of patients with tsms appear visual deficits . 
 this study aimed to investigate the surgical indications of exploring the optic canal and visual prognostic factors in the neurosurgical treatment of tsms.methods:totally 21 patients with tsm , who were operated from september 2007 to august 2011 in the department of neurosurgery , tongren hospital were enrolled in this study . 
 results of orbital computed tomography ( ct ) and magnetic resonance imaging ( mri ) , visual acuity , goldmann visual field test , orbital color doppler flow imaging ( cdi ) test in these patients were retrospectively analyzed.results:visual deficit and optic canal involvement ( oci ) were detected in all the 21 patients . 
 fourteen patients had bone proliferation within the area of the optic canal . after the operation , 
 visual outcomes were improved in 13 patients , unchanged in 7 patients , and deteriorated in 1 patient . 
 all the 21 patients performed orbital cdi test preoperatively , the results showed that if the peak systolic velocity ( psv ) of central retinal artery ( cra ) value was 8 cm / s , the visual outcome would be better.conclusions:the surgical indications of exploring optic canal in tsm cases included : ( 1 ) the neuroimaging evidences of oci ( ct and/or mri ) ; ( 2 ) psv of cra in orbital cdi test was 8 cm / s ; ( 3 ) visual acuity was below 0.1 ; ( 4 ) visual field deficit . 
 the psv of cra in cdi test could be a prognostic factor for visual outcomes of tsms .