Dural Sinus Stenting
Indiana University School of Medicine
Case
Chronic headaches
Initial Presentation
Meet Sarah, a 15-year-old girl who presents to the clinic with a three-month history of progressive headaches.
Initial Presentation
Meet Sarah, a 15-year-old girl who presents to the clinic with a three-month history of progressive headaches.
Vital Signs
120/80 mmHg
78 bpm
16 breaths per minute
98.6°F (37°C)
Initial Presentation
Meet Sarah, a 15-year-old girl who presents to the clinic with a three-month history of progressive headaches.
Vital Signs
120/80 mmHg
78 bpm
16 breaths per minute
98.6°F (37°C)
Physical Exam Findings
Decreased visual acuity bilaterally
Papilledema evident
Cranial nerves intact, no motor or sensory deficits
Whooshing sound heard upon auscultation of the ear
Given Sarah’s presentation of severe headaches, visual disturbances, and pulsatile tinnitus, what is the most likely diagnosis?
✗Migraine
✗Cluster headache
✓Idiopathic intracranial hypertension
✗Tension headache
✗Secondary hypertension
Answer and Explanation
Answer: C. Idiopathic intracranial hypertension
Explanation: Sarah’s symptoms of severe headaches, visual disturbances, and pulsatile tinnitus are characteristic of IIH, especially when accompanied by papilledema, which should be confirmed on further examination.
Visit to the Primary Care Physician
Sarah’s primary care physician performs a comprehensive history and physical examination. Given her symptoms, Sarah is referred to an ophthalmologist for further evaluation of her visual complaints.
During the ophthalmology appointment, the ophthalmologist performs a fundoscopy and discovers papilledema. What does the presence of papilledema suggest in the context of Sarah’s symptoms?
✗It is a benign finding with no significance
✓It suggests increased intracranial pressure
✗It indicates a possible retinal detachment
✗It confirms a diagnosis of glaucoma
✗It is indicative of optic neuritis
Answer and Explanation
Answer: B. It suggests increased intracranial pressure
Explanation: Papilledema is swelling of the optic disc due to increased intracranial pressure, which aligns with Sarah’s symptoms of headaches and vision changes. It requires prompt further investigation.
Seeking Further Medical Attention
Following the discovery of papilledema, Sarah’s ophthalmologist refers her back to the primary care physician with a recommendation for neuroimaging and further evaluation by a neurologist.
What is the next best step in the evaluation of Sarah’s condition, considering her symptoms and the finding of papilledema?
✗Prescribe migraine medication
✓Order a brain MRI and MRV
✗Start corticosteroids
✗Refer to a neurologist
✗Schedule a follow-up in three months
Answer and Explanation
Answer: B. Order a brain MRI and MRV
Explanation: The next step is to confirm the diagnosis of IIH and rule out other causes of increased intracranial pressure. An MRI can help exclude mass lesions, while an MRV can identify venous sinus stenosis.
Diagnostic Imaging
Sarah undergoes a brain MRI, which comes back normal, ruling out any masses or structural abnormalities. However, the MRV reveals stenosis of the transverse sinuses.
What is the most appropriate initial step in management?
✗Observe and re-evaluate in six months
✗Start migraine prophylaxis
✓Perform a lumbar puncture to assess opening pressure
✗Immediate venous sinus stenting
✗Initiate anti-inflammatory treatment
Answer and Explanation
Answer: C. Perform a lumbar puncture to assess opening pressure
Explanation: Given the MRI findings and symptoms suggestive of increased intracranial pressure, a lumbar puncture is crucial to measure the opening pressure and confirm the diagnosis of idiopathic intracranial hypertension.
Management Plan
Sarah’s lumbar puncture reveals an elevated opening pressure of 30 cm H2O, confirming the diagnosis of IIH. Initial management with acetazolamide 500 mg twice daily and lifestyle modifications is started.
What is the primary mechanism of action of acetazolamide in the management of IIH?
✗Increases cerebrospinal fluid (CSF) absorption
✓Decreases CSF production
✗Reduces cerebral blood flow
✗Acts as a diuretic to reduce intracranial pressure
✗Enhances cerebral oxygen delivery
Answer and Explanation
Answer: B. Decreases CSF production
Explanation: Acetazolamide is a carbonic anhydrase inhibitor that reduces cerebrospinal fluid production, thereby lowering intracranial pressure. This is supported by clinical guidelines for IIH management.
Persistent Symptoms
Despite initial treatment with acetazolamide and lifestyle modifications, Sarah’s symptoms persist, and her vision continues to deteriorate.
According to the latest guidelines, what is the recommended next step in Sarah’s management, considering her refractory symptoms and worsening vision?
✗Add topiramate to her treatment
✓Increase the dose of acetazolamide to 1000 mg twice daily
✗Refer to interventional radiology for dural sinus stenting
✗Start corticosteroids
✗Observe and re-evaluate in six months
Answer and Explanation
Answer: B. Increase the dose of acetazolamide to 1000 mg twice daily
Explanation: Before proceeding to more invasive options, increasing the dose of acetazolamide is a reasonable next step to attempt to better manage intracranial pressure as per guidelines.
Counseling on Treatment Options
Sarah’s symptoms remain refractory to maximum medical therapy. She is counseled on further treatment options, including ventriculoperitoneal (VP) shunt and dural sinus stenting.
What are key factors to consider when counseling a patient on choosing between a VP shunt and dural sinus stenting for IIH?
✗Invasiveness of the procedure
✗Risk of complications and need for revisions
✗Patient preference and lifestyle
✓All of the above
✗Cost and accessibility of treatment
Answer and Explanation
Answer: D. All of the above
Explanation: Key factors include the invasiveness of the procedure, the risk of complications and need for revisions, and the patient’s preference and lifestyle. Dural sinus stenting is less invasive and typically has fewer complications compared to VP shunting.
Decision and Procedure
Sarah opts for dural sinus stenting after discussing her options with her healthcare team. She is referred to an interventional radiologist and undergoes venous angiogram to evaluate for stenosis.
During the dural sinus stenting procedure, what is the minimum pressure gradient on venography recommended for stenting according to guidelines?
✗2 mmHg
✓4 mmHg
✗6 mmHg
✗8 mmHg
✗10 mmHg
Answer and Explanation
Answer: D. 8 mmHg
Explanation: According to guidelines, a minimum pressure gradient of 4 mmHg is recommended on venography to justify st
Follow-Up and Outcome
After the stenting procedure, Sarah’s symptoms significantly improve. Her headaches diminish, her vision is restored, and the pulsatile tinnitus resolves.
What follow-up care is recommended for Sarah post-stenting to ensure continued improvement and monitor for potential complications?
✗Regular neurological assessments
✗Periodic imaging to monitor stent patency
✗Continued acetazolamide therapy
✓All of the above
✗Biannual comprehensive eye exams
Answer and Explanation
Answer: D. All of the above
Explanation: Post-stenting care includes regular neurological assessments, periodic imaging to ensure the stent remains patent, and continued acetazolamide therapy to manage intracranial pressure. These recommendations align with follow-up guidelines for IIH.
Challenge Questions
Predictive Factors for DVSS Success
Which of the following factors is most predictive of a successful outcome following dural venous sinus stenting (DVSS) for IIH?
✗Patient’s age
✓Reduction in trans-stenotic pressure gradient
✗Initial severity of papilledema
✗Duration of symptoms before treatment
✗Overall health and comorbidity profile
Answer and Explanation
Answer: Reduction in trans-stenotic pressure gradient
Explanation: The review identifies that a significant reduction in the trans-stenotic pressure gradient is a key predictive factor for successful outcomes following DVSS in IIH patients.
Differential Diagnosis of IIH
Which condition must be ruled out to definitively diagnose idiopathic intracranial hypertension (IIH)?
✗Normal pressure hydrocephalus
✗Chiari malformation
✗Subarachnoid hemorrhage
✓Venous sinus thrombosis
✗Meningitis
Answer and Explanation
Answer: Venous sinus thrombosis
Explanation: To definitively diagnose IIH, venous sinus thrombosis must be ruled out, as it can present with similar symptoms but requires different management.
Improvement in Visual Disturbances
What percentage of patients experienced improvement in visual disturbances after undergoing venous sinus stenting, according to the meta-analysis?
✗75%
✗80%
✓88%
✗95%
✗92%
Answer and Explanation
Answer: 88%
Explanation: 88% of patients experienced improvement in visual disturbances after undergoing venous sinus stenting.
Reduction in Acetazolamide Dosage
What is the average reduction in acetazolamide dosage following DVSS at the 3-month postoperative assessment?
From 1000mg to 500mg daily
✗From 750mg to 250mg daily
✓From 950mg to 300mg daily
✗From 500mg to 100mg daily
✗From 1200mg to 600mg daily
Answer and Explanation
Answer: From 950mg to 300mg daily
Explanation: The average daily dose of acetazolamide decreased from 950mg to 300mg at the 3-month postoperative assessment following DVSS.
Impact of Comorbid Conditions
How do comorbid conditions such as polycystic ovary syndrome (PCOS) impact the management of IIH?
✗They do not impact the management of IIH
✗They complicate the diagnosis but not the treatment
✓They may necessitate a multidisciplinary approach to treatment
✗They only affect the choice of surgical intervention
✗They require specialized pharmacological interventions
Answer and Explanation
Answer: They may necessitate a multidisciplinary approach to treatment
Explanation: Comorbid conditions such as PCOS can affect the management of IIH, requiring a multidisciplinary approach to address both IIH and the underlying conditions.
Summary
- IIH is characterized by increased intracranial pressure without a detectable cause.
- Diagnosis involves imaging and lumbar puncture to measure opening pressure, following the latest guidelines.
- Initial management includes medication and lifestyle changes, with dural sinus stenting as an option for refractory cases, supported by current clinical guidelines.
Authors
Authors: Mirindi T. Kabangu & Noor U. Malik
Contact: mkabangu@iu.edu & noumalik@iu.edu
