CT Cisternogram Findings in Idiopathic Cerebrospinal Fluid Leaks with Emphasis on Long Term Management

Abstract

To study the various computed tomography (CT) cisternogram findings in idiopathic cerebrospinal fluid (CSF) leaks and the long term treatment modalities after surgical repair of idiopathic CSF leaks. This was a descriptive study conducted among 25 patients in MCV memorial ENT trust hospital, Pollachi between May 2014 and May 2020 amongst patients who underwent CT cisternogram for unilateral or bilateral spontaneous rhinorrhea with or without associated headache, visual disturbances and papilloedema diagnosed to be idiopathic CSF leak by investigations. These patients then underwent CSF leak repair and postoperatively were managed with weight reduction, low salt diet and diuretic therapy. Post surgery these patients were followed up for a period of 12 months and were evaluated on the basis of presence or absence of headache, rhinorrhea and papilloedema at the end of 1st month, 3rd month, 6th month and 1 year and data was collected. CT cisternogram findings were evaluated by proportion method and evaluation of long term management was done using proportion and repeated measures ANOVA for all patients. Evidence of the presence of previously mentioned CT cisternogram or contrast MRI findings at the end of 1 year of post-surgical treatment was recorded where patients were willing for the same. CT Cisternography was done for all patients and 72% patients had empty sella appearance while 28% had partially empty sella. Other findings included perioptic filling, optic blunting and arachnoid pits which were found in 11(44%), 8(32%) and 12(48%) of patients respectively. Only 3(12%) out of 25 patients had an encephalocoele. The commonest site of leak in CT cisternography was the cribriform plate (52%) followed by lateral recess of sphenoid (48%). None of the patients had multiple sites of leak in CT cisternography. On follow up post surgery maximum resolution of symptoms was found at the end of 12 months where 23 out of 25 patients improved. In our study, out of 25 only 5 patients agreed to undergo post diuretic therapy MRI scan out of which 2 patients had partially empty sella and 3 had normal sella indicating resolution of BIH. CT cisternography is an important investigation which aids in the diagnosis of CSF rhinorrhea due to idiopathic intracranial hypertension (IIH). The medical management of IIH post surgery such as weight reduction, salt restriction and diuretic therapy is also crucial to prevent recurrence of symptoms.

Keywords: Cerebrospinal fluid rhinorrhea; Computed tomography; Idiopathic intracranial hypertension; Spontaneous.

Fig. 1

a CT image showing empty sella (white arrow), b CT image showing partially empty sella

Fig. 2

a, c, d CT image showing perioptic filling, b CT image showing optic nerve tortuosity