29 Cerebral Venous Thrombosis

Cerebral Venous Thrombosis

Clinical Presentation

A 34-year-old woman presented with a 2-day history of headache of fluctuating intensity. On the day of admission, the headache had worsened markedly and she had developed nausea and vomiting. No vascular risk factors were known except for smoking and a prescribed estrogen-containing contraceptive. On admission, the neurologic examination revealed no focal neurologic deficits or meningeal signs.

Initial Neuroradiologic Findings

Cranial CT did not demonstrate presence of ischemic parenchymal lesions. However, the right transverse sinus (TS) appeared hyperdense (Fig. B29.1).

Suspected Diagnosis

Cerebral venous thrombosis (CVT) of the right TS.

Questions to Answer by Ultrasound Techniques

Was the pulsatility index in the brain-supplying arteries raised as an indirect sign of increased intracranial pressure?
Were there signs of intracranial venous collateral drainage pathways?

Initial Neurosonologic Findings (Day 1)

Extracranial Duplex Sonography

B-mode sonography demonstrated normal findings in the carotid and vertebral arteries.

Transcranial Duplex Sonography

All intracranial arteries showed normal flow signals with a regular pulsatility index of ~0.8, arguing against a severely raised intracranial pressure. Assessment of the intracranial veins revealed a prominent flow signal in both basal veins of Rosenthal (BVRs) (flow velocity: left, 20/16 cm/s; right, 31/25 cm/s), the right deep middle cerebral vein (DMCV) (flow velocity 29/25 cm/s), and the left sphenoparietal sinus (SpPS) (flow velocity 25/20 cm/s). No flow signal could be detected in projection of the right TS. The contralateral TS revealed raised flow velocities (flow velocity: 41/34 cm/s) (Figs. B29.2, Fig. B29.3, Fig. B29.4, Fig. B29.5, Fig. B29.6; see also Video B29.1).

Conclusion

The neurosonologic findings were suggestive of a right TS occlusion because of the raised left TS flow and of an additional superior sagittal sinus (SSS) flow obstruction because of the raised flow in the deep cerebral veins. The left TS and SpPS as well as both BVRs appeared as the main alternative drainage pathways.

CT Angiography (CTA) (Day 1)

CTA confirmed a thrombosis of the distal SSS extending to the right TS and sigmoid sinuses (SiS) down to the right superior jugular bulb (Fig. B29.7 and Fig. B29.8).

Clinical Course (1)

Intravenous heparin was initiated, aiming for a twofold increase of partial thromboplastin time (PTT). In the following 2 days the patient’s headache completely resolved. Treatment was then changed from heparin to oral anticoagulation with phenprocoumon. The etiology of the thrombosis remained unclear. There was no thrombophilia or underlying inflammatory disease. Follow-up investigations were performed 90 and 180 days later.

Question to Answer by Ultrasound Techniques

Was there evidence for recanalization of the occluded sinuses over time?

Follow-up Neurosonologic Findings (Day 90)

Transcranial Duplex Sonography

The BVR now revealed an almost normal but not completely normalized flow signal on both sides (flow velocity: left, 19/15 cm/s; right, 19/14 cm/s) (Fig. B29.9 and Fig. B29.10). Low flow signals were also seen in the right DMCV and in the left SpPS (not shown). The TSs were not examined.

Conclusion

Marked improvement of the neurosonologic findings with diminished flow velocity in the venous collateral vessels indicative of advanced recanalization of the right TS and SSS.

Question to Answer by Ultrasound Techniques

Was there further evidence for normalization of venous hemodynamics?

Follow-up Neurosonologic Findings (Day 180)

Transcranial Duplex Sonography

Both BVRs now showed a completely normal flow signal (flow velocity: left, 11/9 cm/s; right, 14/11 cm/s). No flow signals could be detected within the right DMCV and the left SpPS. Both TSs revealed normal flow signals (flow velocity: left, 16/12 cm/s; right, 14/11 cm/s) (Fig. B29.11, Fig. B29.12, Fig. B29.13, Fig. B29.14).

Conclusion

Complete normalization of intracranial venous hemodynamics indicative of vessel restitution of the right TS and SSS.

Clinical Course (2)

Clinical follow-up after 6 months was unremarkable. MRI after 6 months revealed no parenchymal lesions. Time-of-flight MR angiography (TOF-MRA) demonstrated a complete recanalization of the right TS and the SSS (Fig. B29.15). Anticoagulation with phenprocoumon was stopped.

Final Diagnosis

Extended CVT involving the distal SSS and the right TS, SiS, and jugular bulb. There was complete recanalization after 6 months while the patient was on oral anticoagulation.

Fig. B29.1 Unenhanced cranial CT, axial plane. No ischemic parenchymal lesions. Note the hyperdense right TS (arrows).

Fig. B29.2 TCCS (transtemporal approach), left-sided insonation, midbrain/thalamic plane. Mildly increased flow in the left basal vein of Rosenthal (flow velocity 20/16 cm/s).

Fig. B29.3 TCCS (transtemporal approach), right-sided insonation, midbrain/thalamic plane. Increased flow velocity in the right basal vein of Rosenthal (flow velocity 31/25 cm/s).

Fig. B29.4 TCCS (transtemporal approach), right-sided insonation, midbrain plane. Raised flow velocity in the right DMCV (flow velocity 29/25 cm/s).

Fig. B29.5 TCCS (transtemporal approach), left-sided insonation, upper pontine plane. Flow velocity of 26/20 cm/s in the left SpPS.

Fig. B29.6 TCCS (transtemporal approach), right-sided insonation, oblique plane. Raised flow velocities in the left TS (flow velocity 41/34 cm/s).

Fig. B29.7 Intracranial CTA, sagittal maximal intensity projection (MIP). Lack of contrast enhancement within the posterior part of the SSS (arrows).

Fig. B29.8 Intracranial CTA, coronal MIP. Thrombus extension into the right superior jugular bulb, as indicated by a lack of contrast filling (arrow).

Fig. B29.9 TCCS (transtemporal approach), left-sided insonation, midbrain plane. Left basal vein of Rosenthal demonstrating an almost unchanged flow signal (flow velocity 19/15 cm/s).

Fig. B29.10 TCCS (transtemporal approach), right-sided insonation, thalamic plane. Right basal vein of Rosenthal demonstrating a nearly normalized flow signal (flow velocity 19/14 cm/s).

Fig. B29.11 TCCS (transtemporal approach), left-sided insonation, midbrain plane. The left basal vein of Rosenthal in its proximal part showing a normal flow signal (flow velocity 11/9 cm/s). Note the corresponding signal of the proximal P2-PCA (flow velocity: 63/30 cm/s).

Fig. B29.12 TCCS (transtemporal approach), right-sided insonation, thalamic plane. Normalized flow signal in the right basal vein of Rosenthal (flow velocity 14/11 cm/s).