Paradoxical association of symptomatic cerebral edema with local hypoperfusion caused by the ‘watershed shift’ after revascularization surgery for adult moyamoya disease: a case report

Abstract

Superficial temporal artery–middle cerebral artery anastomosis is generally considered as an effective method in improving damage associated with intracerebral occlusions in moyamoya disease. Hemodynamic changes caused by revascularization are the cause of many postoperative complications. Of the 186 consecutive surgeries for moyamoya disease at our hospital from 2015, we herein presented one case of adult-onset moyamoya disease that manifested symptomatic local cerebral edema and local hypoperfusion caused by the ‘watershed shift’. A 67-year-old woman presented with limb numbness on the right side and underwent superficial temporal artery–middle cerebral artery anastomosis, resulting in neurological dysfunction and the formation of a reversible high-signal lesion at left frontotemporal lobes on T2-weighted images along with a decrease in perfusion values on 123I N-isopropyl-p-iodoamphetamine single-photon emission computed tomography, while the anastomotic vessel was patent on magnetic resonance angiography. This phenomenon of hypoperfusion area (left frontotemporal lobe) remote to anastomotic site (left temporal lobe area) led to the diagnosis of the ‘watershed shift’ phenomenon. In light of the hypoperfusion induced by ‘watershed shift’, the patient was treated with fluid replacement. With the gradual recovery of perfusion, the patient presented significantly improvement both on the magnetic resonance imaging findings and neurological symptoms. In conclusion, regional cerebral edema with hypoperfusion, possibly due to cerebral ischemia and the ‘watershed shift’ phenomenon, may be another novel entity that needs to be considered as a potential complication after extracranial–intracranial bypass for moyamoya disease.

Cerebral Hyperperfusion and Concomitant Reversible Lesion at the Splenium after Direct Revascularization Surgery for Adult Moyamoya Disease: Possible Involvement of MERS and Watershed Shift Phenomenon

“…Dynamic and heterogeneous hemodynamic changes are evident after STA–MCA anastomosis for MMD. 3 – 15 , 29 , 30) In the previous reports, the WS phenomenon was defined as paradoxical decrease of CBF adjacent to the site of local CHP. 10 – 15) On the contrary, the current case demonstrated CHP and concomitant reversible lesion at corpus callosum, which is atypical to WS phenomenon.…”

“…Superficial temporal artery (STA)–middle cerebral artery (MCA) bypass is a standard surgical procedure for patients with moyamoya disease (MMD). 1 , 2) However, intensive perioperative management is required to avoid perioperative complications, 3 – 15) such as cerebral hyperperfusion (CHP) 3 – 9) and hemodynamic ischemia due to the “watershed shift (WS) phenomenon,” 10 – 15) defined as the paradoxical decrease in the cerebral blood flow (CBF) value near the site of CHP, as reported previously. Previous reports showed that the WS phenomenon was evident in 10.9% of adult MMD patients after STA–MCA anastomosis.…”

“… 13) Although the outcome of the WS phenomenon is favorable, 13) the WS phenomenon could result in cerebral infarction and permanent neurological deficits. 13 – 15) In addition, STA–MCA bypass could enhance intrinsic inflammatory response and oxidative stress response in patients with MMD, 16 – 20) which can contribute to the formation of vasogenic edema and intracerebral hemorrhage. Then, the detection of heterogeneous hemodynamic and inflammatory changes and intensive postoperative management is critical after STA–MCA anastomosis for MMD.…”

“…Then, the detection of heterogeneous hemodynamic and inflammatory changes and intensive postoperative management is critical after STA–MCA anastomosis for MMD. 10 , 13 – 15) To detect heterogenous and dynamic hemodynamic changes and perform intensive management, such as prophylactic blood pressure lowering 21) and administration of minocycline hydrochloride, 22) we have introduced serial [ 123 I] iodoamphetamine single-photon emission computed tomography ( 123 I-IMP-SPECT) 23 , 24) and MRI 25) studies in the acute phase of revascularization surgery for MMD. Among 525 consecutive revascularization surgeries for MMD patients, we report a rare patient who developed local CHP and concomitant remote reversible lesion at the splenium after STA–MCA bypass, with marked regression of periallosal artery.…”

Severe cerebral edema induced by watershed shift after bypass in a patient with chronic steno-occlusive disease: a case report and short literature review

“…"Watershed shift", a special hemodynamic change of CHS, occurs after dual anastomosis. And the phenomenon presents more often in pediatric moyamoya disease (MMD) than in adult MMDs [7]. Here, we describe a male patient with chronic occlusion of internal carotid artery (ICA) and middle cerebral artery (MCA) who developed severe massive cerebral edema after left dual EC-IC bypass and encephalo-duro-myo-synangiosis (EDMS).…”