Journal of Neuro-Ophthalmology, June 1981, Volume 1, Issue 2

Computed tomographic sellar and perisellar evaluation. Use of high-dose continuous contrast infusion.

Contrast enhancement provides valuable information in cranial computed tomography. We report the use of high-dose continuous contrast infusion as a means of consistently demonstrating major perisellar cerebral vasculature. This method was utilized in examining 73 patients, and three illustrative cases are presented. We propose that this technique be performed as the initial radiographic procedure in evaluating sellar and perisellar lesions. Results of clinical, laboratory, and CT examinations may necessitate additional studies including sellar complex motion polytomography, cerebral angiography, metrizamide CT cisternography, or pneumoencephalography. However, employing the CT techniques described, the role of invasive neuroradiographic procedures in the preoperative evaluation of the sellar and perisellar region requires reconsideration.

1. Clin. NeUrtl-l1phth.llnwl. I: 1~1-152, IQt\1. Computed Tomographic Sellar and Perisellar Evaluation Use of High-Dose Continuous Contrast Infusion lAMES D. ACKER, M.D. LANNING B. KLINE, M.D. IIRI J. VITEK, M.D, Abstract Contrast enhancement provides valuable information in cranial computed tomography. We report the use of high-dose continuous contrast infusion as a means of consistently demonstrating major peri sellar cerebral vasculature. This method was utilized in examining 73 patients, and three illustrative cases are presented. We propose that this technique be performed as the initial radiographic procedure in evaluating sellar and perisellar lesions. Results of clinical, laboratory, and CT examinations may necessitate additional studies including sellar complex motion polytomography, cerebral angiography, metrizamide CT cisternography, or pneumoencephalography. However, employing the CT techniques described, the role of invasive neuroradiographic procedures in the preoperative evaluation of the sellar and perisellar region requires reconsideration. Diagnostic accuracy of computed tomography (CT) of the brain has been improved by utilizing high doses of intravenous contrast medium I-I and supplementing axial projections with coronal views. I The use of continuous drip infusion of contrast further delineates the pathological process and its relationship to cerebral vasculature. By applying these modalities in the initial evaluation of the sellar and perisellar region, our findings suggest CT may, in many cases, be the only neu­roradiographic study necessary prior to surgery. Methods Suspected of having intra- and perisellar lesions, 73 patients were evaluated at the University of From the Department of Radlologv (JDA, "V). Unlver"tv of Alabama Hospitals, BirminghJm, J~d Dep.Htment "f (lphth.,I­mology, Eye FoundatIOn Ho'pltJI (LHK), HIriTlIngh.lnl, AI.,­bama. • Presented at the EIghteenth AnnuJI Mel'tlng, the AJllerJ(.m Society of Neuroradiology, Lo' Angele', (.,Idon"." M.m h 1(>­21,1980. June 1981 Alabama Hospitals in Birmingham from 1978 to 1980. Following neuro-ophthalmologic, neurologic, and endocrinologic evaluation, all patients were examined with a GE CT/T 8800 scanner. A non­contrast axial CT scan was performed using 10­mm section thickness and selected tomograms were chosen for study with contrast enhancement. After an intravenous bolus injection of 18-36 g of iodine, the patient received an additional continu­ous 42-g iodine drip infusion, during which 5-mm axial and coronal tomograms were obtained. The coronal views were performed with the anteropos­terior coronal technique ("hanging-head" position) with the gantry tilted to 10- IS oc, Magnification was used in evaluating regions of interest. Three illustrative cases are presented. Case Reports Case 1 A 47-year-old man noted gradual, progressive visual loss over a 1!-ye.u period. Specifically, he recalled "missing numbers on road signs," .md occasionally missing sight of llnnln1ing automo­biles. Three months prior to examin.1tion, he e,­perienced the onset of constant front.ll head.Khes. Neuro-ophthalmologic testing revealed best Cllr­rected vision of 20/50, right eye, .md 20/70, left eye. Pupillary reactions, extraocul.u movements, and slit lamp examination were norm.l!. While the optic discs appeared norm.ll, .1 dense bitempor.11 hemianopia was found on visu.ll field testing. Neu­rological examin.1tion W.1S otherwise un rem.uka­ble. Radiographs of the skull showed .1 double con­tour to the floor of the selb, while CT demon­str. lted depression of the right side of the sellar floor with extension of a large mass into the supra­sellar region (Figs. 1 and 2). Cerebral angiography excluded an aneurysm. At craniotomy, a pituitary adenoma was found. 141 C"mputed T"nlll~r.lphicSell.u .1I1J I'erisell.u [v.lluJtilln Fi!\ur~ I. CJ'l' I-piluil.lrv ,ldCllllnl.,. (.J-d ) C'H'lr.15I-cnhJn,cd ,,,.i,11 CT ~('ri('s ... hl)W~ .1 ~lliid tUfll\lf .1I1d il~ rd.llilll)ship tl) periscll.u \'.l~('utltur('. (.1 ) Supr.Klilll1id , •• ",tid .trl"r;", (CAl: (I» b.lSiI.lr IHA) .llld lefl p,'ster;,)r ,cre­br., 1 ,trterie' WCAl: (e) ,,~ht p",tcri,)r Cl'rebr.,1 "'tcrv (PCAl: (d) A-I 'l'gnH'nh "f .1Ilt,'""r ,erebr.,1 .trleri,', (AC). '; I' Journal of Clinical Neuro-ophthalmoJog) June 1981 .. ..,. 411 7' I ,,- peA \ ; .. • c , '. - • Figure 1. (Continued.J Acker, Kline, Vitek 143 Computed Tomographic Sell.H and ['('risell.H Evaluation Figure 2. C."l' l-pituit.HV ,1dl'I1l'111,1 (,,-, ) C'1I1tr,"I-l'nh,111Cl'd «'ron,ll CT seriet.; shuw<., tUIlHlf extending IIltl' the sLJpr~lsl'll.H cisterns. (.J ) A density difference between the tUIlHlf .tlll! (.l\'Crlll)lIS sinus (.nfll"'''') ,llll)\\'s .lssess­ml'nl or I,llcr.lll'xlension. (I>. ,) The A-I sl'gl11l'nts "r lhl' ,111t('rior cerebral .Htl'ril's (AC) .He displ,Kl'd upw.lI'd bv the tun",r. Journal of Clinical Neuro-ophthalmology Acker. Kline, Vitek Figure 2. (Continued .j Case 2 A 60-year-old mall' accountant experienced dif­ficulty concentrating at work. He reported a 30-lb. weight loss, cold intolerance, decreased libido, and persistent polyuria and polydypsia. One year after the onset of symptoms he was found to have panhypopituitarism and diabetes insipidus. CT scan of the brain was reported within normal limits. Two years after the onset of symptoms, reeval­uation documented decreased serum cortisol, T4 and TSH levels. Neuro-opthalmologic examination :demonstrated best corrected vision of 20/20, right eye, and 20/70, left eye. Pupillary testing revealed a left afferent pupillary defect (Marcus Gunn). Extraocular movements and slit lamp examination were normal. While the appearance of the optic discs was unremarkable, visual field testing dem­onstrated a bitemporal hemianopia. Complex mo­tIOn polytomography documented erosion of the sellar floor, while CT demonstrated a mass lesion with suprasellar extension (Figs. 3 and 4). Lateral displacement of both intracavernous carotid arter­ies was seen with cerebral angiography. A left frontal craniotomy was performed with subtotal removal of a craniopharyngioma. Case 3 A.51-year-old woman complained of severe gen­erahzed headaches of 6 months' duration. At that time, neurological examination revealed only June 1981 slightly decreased strength in the right upper ex­tremity. Plain skull roentgenograms and techne­tium brain scan were normal, and an electroen­cephalogram demonstrated mild diffuse slowing. Cerebrospinal fluid was normal with the exception of an elevated protein of 72 mg%. One year after the onset of headaches, neuro­ophthalmologic examination revealed best cor­rected vision of 20/30, right eye, and 20/100, left eye. Pupillary reactions, extraocular movements and slit lamp examination were normal. Visual field testing demonstrated a bitemporal hemiano­pia and the optic discs were pale. An intrasellar mass with a low-density center extending into the suprasellar region was documented with CT (Fig. S). A craniopharyngioma was found at craniotomy. Discussion When clinical and laboratory data suggest a sellar or perisellar lesion, a battery of neuroradi­ographic procedures are available including plain sellar films, sellar complex motion polytomogra­phy, CT with contrast enhancement, metrizamide cisternography, metrizamide CT cisternography, cerebral angiography, and pneumoencephalogra­phy. A dilemma arises as to which modality or modalities are sufficient to delineate the lesion and demonstrate effects on surrounding neural and vascular structures. 145 Computed Tomogr,lphic 5(>11.11" ,1Ild PeriseliM Ev.lluation Figure 3. CJSl.' 2-(r.mioph,lrvngillm.1. (.1-' ) Cllntr.lsl-l'nh.lnced .1,i,,1 s"ries rl.'vl.'JIs 'obulJtl.'d tumor (l11lt.lining Me.1S "f dl.'CCl·.lSl.'d dl.'nsily. (J) Th" 1.ltN,11 bordl.'C' (MrowS) llf (',\(h (,lVl.'nlllUS sinus Ml.' intJl"!, Yl.'t thl.' normal infundibular pl<,xus "f veins is n"t id,-ntifil'd. (I>. ( ) Thl' bifurcation (black Jrnlw) of thl.' int,-m.ll (",,,tid .Htl.'ry into til(' middk cl.'r"bral (white arrow) ,md A-I segml.'nts (.lrrowhl.'.lds) is dl.'n1l1nstr,11"d. Journal of Clinical Neuro-ophthalmolog Acker, Kline, Vitek Figure 3. (Continued.l In assessment of bone erosion, sellar tomogra­phy is thought to be superior to CT. However, by using 5-mm coronal tomographic sections with altered window width and levels, and selective magnification of 1.5-2.5, bone erosion can be iden­tified by CT. The recent availability of tomograms of 1.5 mm thickness with CT should further im­prove evaluation of bony abnormalities. CT also allows demonstration of soft tissue relationships. Preoperative examination with CT delineates sphenoid septation and pneumatization. In evalu­ating small sellar tumors, such as prolactinomas, complex motion polytomography and CT provide sufficient information to make further studies un­necessary.'; Recently, in some cases of pituitary microadenoma, detailed coronal CT has eliminated the need for polytomography. ' In determining suprasellar extension of a mass lesion, metrizamide cisternography with complex motion tomography and metrizamide cisternogra­phy with CT have been reported to be .IS accurdte as pneumoencephalography and technicdlly sim­pler to perform."' ~ However, the use of metrizd­mide is not without risk. IfJ-l~ Although axial CT has fallen short of adequately defining suprdsellar extension, the addition of corondl tomograms pro­vides further delineation of the configuration of perisellar masses. The combindtion of dxidl dnd coronal CT with high-dose continuous contr.lst infusion, maintaining a continuous high iodine blood level, provides sufficient morphologic detdil to assess the configuration of tumors and their June 1981 relationships to perisellar vasculature. This has reduced the need for metrizamide and currently metrizamide CT cisternography and pneumoen­cephalography should be reserved for the diagnos­tic dilemma of a necrotic sella tumor versus an empty sella. Traditionally, angiography is requested prior to surgical intervention of sellar and perisellar lesions. This examination provides information regarding vascularity of the tumor, and its relationship to surrounding cerebral vasculature. Certainly, if an aneurysm or vascular malformdtion cannot be ex­cluded, angiography must be performed. While we .Ire not able consistently to visu.llize the intracav­ernous carotid artery, the supr,lsell.H vessels .He demonstrated as are the bound.Hies of the cavern­ous sinus. Case 1 (Figs. 1 and 2) illustrdtes the .Idvantages of high-dose continuous contrast infusion .1l1d mul­tiple CT projections. The .lxi.ll study provides de­linedtion of the mdjor perisell.1r vessels, while the coronal views give .lddition.ll infl)rm.ltil)Jl .1S to Idterdl dnd verticdl extension of the pituit.lry .lde­nom. l. CT examil1.1tion of C.lse 2 (Figs . .3 dnd 4) revedls .I lobulated tumor, cont.lining .He.1S of de­creased attenuation, extending intl) the suprasellar cisterns. These findings are highly suggestive of a craniopharyngioma. The rel.ltionship of this tumor to the major branch of internal carotid dnd basilar arteries is demonstrated by employing both axial and coron.11 projections. In case 3, accurate delin­eation of the size .ll1d extent of the Cfdniopharyn- 147 Computed Tomogr<1phic Sellar and Perisl'll<1r EV.Jlualion Figure 4. Case 2-crdniopharyngiomd. (.,-d) Contrdst-enh.mced coronal series demonstr.ltes .1 lobuldted tumor with .m enhancing cdpsule. (.I ) The bifurcdtion of the bdsilM M1ery is visu.llized. (I:» The boundaries of each cavernous sinus (MCllWS) .He demonstr.lted. dlthough the intracavemous carotids are not seen, (c) Supr,Klinoid carotid arteries are imaged to their bifurcation (Mrow). (d) Elevated A-I sE'gmenls of thE' anterior cerebral arteriE's (arrowheads) Me demonstrated. I I Journal of Clinical Neuro-ophthalmology June 1981 Figure 4. (Continued.J Acker, Kline, Vitek 149 Computed Tomogr,lphic Sell.tr .1nd I'erisell.lr EV.llu.ltion Figure 5. C.lse 3-cr.lnioph.lryn~iom.1. (,,-a) Contr,lst-l'nh.lnced ,Ix;.ll and coronal sNies shows the enh,lIKed c.lpsulc of the tumor. (". b) The .lxi.ll tomograms show the tum(>r within the supr,,,eIlM ,·isterns. The ri~ht c.lrolid bifurc.llion (large .lrrowhe.ld) is visu.Jlized .IS well.ls both A-I sl'~ments (sm.lller arrowheads). (e. d ) The cown.ll views show the supr,Klinoid cMotid MtNies (I.lr~e drrowhead) to their bifurc.llion. (d) The A-I segment of the .lnteri,>r cerebr.ll .lrtery on the right is im.lged (sm.lll .Hwwhe.lds). Journal of Clinical Neuro-ophthalmology A, "cr, Klll1e, Vile" Figure 5. (( llfltl/llH'J.) gioma (Fig. 5) is afforded by the enh..Jncing capsule of the tumor. The effect of this m.1SS lesion upon perisellar vasculature is also illustr.lted. Combining axial and coronal projedions with high-dose continuous contrast infusion provides valuable anatomic information of the sell.u .md June 1981 perisell.u regi'lI1. Continued refinements in CT resolution .lnd im.lge qu.llity will undoubtedly con­tinue. One m.1Y question the need for invasive neuror.ldiogr.lphic studies in every preoperative sell.lr .1I1d perisellilr ev.lluation. Figure 6 summa­rizes our current .lppro.lch. 151 Computed Tomogr,lphic Sell.H ilnd I'erisellilr EVilluiltion INEURO-OPHTHALMOLOGIC AND ENDOCRINE EVALUATION , AXIAL AND CORONAL CT WITH l CONTINUOUS CONTRAST INFUSION I I NORMALl I ABNORMAL I 1 .--------- - - - - - - - -. I SELLAR POLYTOMOGRAPHyl CEREBRAL ANGIOGRAPHY PNEUMOENCEPHALOGRAPHY ! 1. DELINEATE INTRACAVERNOUS OR I MEDICAL THERAPY »f CAROTID ARTERY METRIZAMIDE CT CLINICAL FOLLOWUP 2. RIO ANEURYSM OR VASCULAR CISTERNOGRAPHY MALFORMATION FOR EMPTY SELLA V. NECROTIC SELLAR TUMOR I SURGERY I Figure 6. Algorithm summarizing our current approach to sellar and perisellar evaluation. References 1. Davis, J. M., David, K. R., Newhouse, J., and Pfister, R. C: Expanded high iodine dose in computed to­mography: A preliminary report. Radiology 131: 373-380, 1979. 2. Hayman, L. A., Evans, R. A., and Hinck, V. C: Rapid high-dose contrast computed tomography of iso­dense subdural hematoma and cerebral swelling. Radiology 131: 381-383, 1979. 3. Hayman, L. A., Evans, R. A., and Hinck, V. C: Rapid high dose contrast computed tomography of peri­sellar vessels. Radiology 131: 121-123, 1979. 4. Wolfman, N. R., and Boehnke, M.: The use of coronal sections in evaluating lesions of the sellar and parasellar regions. f. Comput. Assist. Tomogr. 2: 308-313, 1978. 5. Nakagawa, H., and Wolf, B.S.: Delineation of le­sions of the base of the skull by computed tomog­raphy. Radiology 124: 75-80, 1977. 6. Wolpert, SM., Post, K. D., Biller, B. J., and Molitch, M. E.: The value of computed tomography in eval­uating patients with prolactinomas. Radiology 131: II7-1l9,1979. 7. Syversten, A., Haughton, V. M, Williams, A. L., and Cusick, J. F.: The computed tomographic appearance of the normal pituitary gland and pituitary microad­enoma. Radiology 133: 385-391, 1979. 8. Sheldon, P., and Molyneus, A.: Metrizamide cistem­ography and computed tomography for the investi­gation of pituitary lesions. Neuroradiology 17: 83­87,1979. 9. Drayer, B., Kattah, J., Rosenbaum, A., Kennerdell. J., and Maroon, J: Diagnostic approaches to pituitary tumors. Neurology 29: 161-169, 1979. 10. Nickel, A. R., and Salem, J. J.: Clinical experience in North America with metrizamide. Evaluation of 1850 subarachnoid examinations. Acta Radiol. (5uppl.) (Stockh.) 355: 409-416,1977. II. lundervold, A., and Sortland, 0.: EEG disturbances following myelography, cistemography and ventric­ulography with metrizamide. Acta Radio!. (5uppl.) (5tockh.) 355: 379-390,1977. 12. Gelmers, H. J.: Adverse side effects of metrizamide in myelography. Neuroradiology 18: II9-123, 1979. . Write for reprints to: Dr. Lanning B. Kline, 1720 Eighth Avenue, South, Birmingham, Alabama 35233. Journal of Clinical Neuro-ophthalmology