The present study reports the case of a 33-year-old male who presented with Terson syndrome with no cerebral hemorrhage secondary to traumatic brain injury (TBI). A computed tomography scan of the patient, who had sustained an impact injury to the right occipital region, showed no cerebral lesion. Ophthalmoscopy clearly demonstrated vitreous hemorrhage in both eye globes. Vitreous hemorrhage, which results from an abrupt increase in intracranial pressure (ICP), is associated with TBI. In this case, the visual disturbance was attributed to Terson syndrome secondary to TBI. Therefore, close ophthalmological and radiological evaluation is required in patients with TBI, in order to enable the diagnosis of Terson syndrome and an early vitrectomy.
cerebral hemorrhage; intracranial pressure; traumatic brain injury; Terson syndrome; vitreous hemorrhage
Depressive symptoms are common in neurological diseases, at times posing dilemma in organic or functional origin. Cerebrovascular disease may predispose, precipitate, or perpetuate some geriatric depressive syndromes that resemble primary depressions both clinically and therapeutically in about half of the patients following acute stroke. Terson's syndrome is the direct occurrence of vitreous hemorrhage following subarachnoid/subdural hemorrhage, often overlooked in the acute setting. Autosomal dominant (adult) polycystic kidney disease may be associated with berry aneurysms and hypertension, and may lead to intracranial bleeds. We report an unusual case of organic depression and Terson's syndrome in a 50-year-old female with polycystic kidney disease and hypertension, following anterior communicating artery aneurysmal subarachnoid bleed with bilateral subdural extension. Management included anti-hypertensives, antiepileptics, neodymium: YAG laser photocoagulation, and aneurysmal clipping.
Depression; intracranial aneurysm; polycystic kidney disease; subarachnoid hemorrhage; syndrome; vitreous hemorrhage
Terson syndrome is defined as intraocular hemorrhage associated with intracranial bleeding. This syndrome can occur in the event of intracranial hemorrhage or elevated intracranial pressure. To our knowledge, it has never been associated with chronic myeloid leukemia. A 45-year-old woman suffering from chronic myeloid leukemia was referred to our clinic with Terson syndrome after intracranial bleeding. We followed this patient for a year, performing visual acuity assessment, fundus examination, color retinography, and A-scan and B-scan ultrasonography. At presentation, her best-corrected visual acuity on the right was 20/63 and on the left was 20/320. In the right eye, retinoscopy showed blurring of the optic margins surrounded by retinal and preretinal hemorrhages, preretinal fibrosis of the optic disc along the vascular arcades, and perivascular retinal infiltrates. In the left eye, the optic disc was surrounded by retinal and preretinal hemorrhages, and massive fibrosis with hard exudates and severe preretinal hemorrhage were observed at the posterior pole. Roth spots and many circular hemorrhages were noted at the periphery of the retina. A-scan and B-scan ultrasonography did not show intraocular leukemic infiltration. The clinical picture remained stable over the following 12 months. In this patient, we observed the ophthalmoscopic features of chronic myeloid leukemia, but also coexistence of features typical of Terson syndrome. To our knowledge, no similar cases have been reported previously.
retinal disease; chronic myeloid leukemia; eye hemorrhage; intracranial hemorrhage
Intraventricular hemorrhage during pregnancy is usually followed by a poor recovery. When caused by moyamoya disease, ischemic or hemorrhagic episodes may complicate the management of high intracranial pressure. A 26-year-old Caucasian woman presented with generalized seizures and a Glasgow Coma Score (GCS) of 3 during the 36th week of pregnancy. The fetus was delivered by caesarean section. The brain CT in the mother revealed bilateral intraventricular hemorrhage, a callosal hematoma, hydrocephalus and right frontal ischemia. Refractory high intracranial pressure developed and required bilateral ventricular drainage and intensive care treatment with barbiturates and hypothermia. Magnetic resonance imaging and cerebral angiography revealed a moyamoya syndrome with rupture of the abnormal collateral vascular network as the cause of the hemorrhage. Intracranial pressure could only be controlled after the surgical removal of the clots after a large opening of the right ventricle. Despite an initially low GCS, this patient made a good functional recovery at one year follow-up. Management of refractory high intracranial pressure following moyamoya related intraventricular bleeding should require optimal removal of ventricular clots and appropriate control of cerebral hemodynamics to avoid ischemic or hemorrhagic complications.
Pregnancy; Moyamoya syndrome; Intraventricular hemorrhage; Ventriculostomy; Intensive care management
Direct surgical clipping proves to be difficult and dangerous for intracranial aneurysms associated with moyamoya disease (MMD) or moyamoya syndrome (MMS). This study presents our clinical experience of endovascular embolization of intracranial aneurysms associated with these diseases. A total of 13 cases of intracranial aneurysms associated with MMD or MMS were treated by endovascular embolization between January 2001 and January 2009. Patients were divided into two groups: a saccular aneurysm group (n=10) and a pseudoaneurysm group (n=3). Different endovascular therapeutic strategies were employed for each type of case. Of the 13 cases, 11 received successful endovascular embolization and had an uneventful postoperative course during one to two years of follow-up. However, endovascular embolization failed in the other two cases, of whom one died from rebleeding after the five-month follow-up, while the other was conservatively treated and experienced no rebleeding during the two-year follow-up. A favorable prognosis may be secured through careful selection of endovascular treatment regimens for patients with intracranial aneurysms associated with MMD or MMS according to the site of intracranial aneurysms.
moyamoya disease, moyamoya syndrome, intracranial aneurysms, endovascular treatment
Moyamoya disease is a clinical entity characterized by progressive cerebrovascular occlusion with spontaneous development of a collateral vascular network called Moyamoya vessels. This disease mainly manifests as cerebral ischemia. Intracranial bleeding is another major presentation of patients with Moyamoya disease. We report here a 12-year-old male child who presented with severe headache, vomiting and meningismus. Initial neuroimaging study with noncontrast computed tomography scan revealed fresh intraventricular hemorrhage in right-sided lateral ventricle. Magnetic resonance imaging with angiography of brain was done 5 days later when the child developed right-sided hemiparesis, and the diagnosis of Moyamoya disease was confirmed along with lacunar infarction of right posterior peri and paraventricular area and in the left paraventricular area and centrum semiovale. Simultaneous presence of cerebral infarction along with intraventricular hemorrhage in adult with bleeding-type Moyamoya disease is reported in literature, but it is a rare entity in a child.
Cerebral infarction; intraventricular hemorrhage; Moyamoya disease; pediatric
Prevention of rebleeding plays an important role in the treatment of hemorrhagic moyamoya disease, because rebleeding results in high mortality and morbidity. We discuss possible treatment for patients with moyamoya disease accompanied with distal choroidal artery aneurysms and review the literature to summarize clinical treatment and mechanisms. The cases of three male patients who suffered from intraventricular hemorrhage are presented. Computed tomography (CT) and digital subtractive angiography (DSA) revealed that bleeding was believed to be caused by ruptured aneurysms originating from distal choroidal artery aneurysms. Two patients successfully underwent superficial temporal artery (STA)-middle cerebral artery (MCA) bypass combined with encephalo-duro-myo-synangiosis (EDMS) and the obliteration of the aneurysm. The follow-up DSA or CT scan demonstrated that the aneurysms completely disappeared with the patency of the reconstructed artery. Neither of the patients experienced rebleeding during the follow-up period (up to 34 months). Given conservative treatment, the third patient experienced recurrent hemorrhages 4 months after the first ictus. This study describes treatment for moyamoya disease accompanied with distal choroidal artery aneurysms. Our experience suggests that cerebral revascularization combined with obliteration of the complicated distal aneurysm in the same session is a possible treatment.
Aneurysm; Intracranial hemorrhage; Revascularization; Moyamoya disease
The presentation of moyamoya disease (MMD) as an aneurysmal subarachnoid hemorrhage (SAH) is relatively frequent and in the absence of aneurysms is extremely rare.
A 53-year-old male patient suddenly developed severe headache associated with dysarthria and an altered state of consciousness. At the time of admission, he was found drowsy with global aphasia, stiff neck, right hemiparesis and right Babinski's sign. A non-contrast brain computed tomography was performed and a small bleeding in the subarachnoid space over the left frontal and parietal cortex was observed. Four-vessel cerebral angiography showed bilateral stenosis of the internal carotid arteries, with multiple tortuous vessels branching from the anterior and middle cerebral arteries. These abnormal vessels were anastomosing with branches from the posterior cerebral and middle meningeal arteries. With this information, a diagnosis of MMD was made. A three-dimensional reconstruction from digital angiography ruled out aneurysms or vascular malformations. After 4 weeks, another angiography was performed and remained the same as previous one.
Clinical and radiological characteristics of this case are consistent with previous reports, supporting the theory that non-aneurysmal SAH in MMD is caused by rupture of fragile moyamoya vessels.
Moyamoya; subarachnoid hemorrhage; vascular anastomosis
Moyamoya syndrome, a vasculopathy characterized by chronic progressive stenosis at the apices of the intracranial internal carotid arteries, is an increasingly recognized entity which is associated with cerebral ischemia. Diagnosis is made on the basis of clinical and radiographic findings, including a characteristic stenosis of the internal carotid arteries in conjunction with abundant collateral vessel development. Adult moyamoya patients often present with hemorrhage, leading to rapid diagnosis. In contrast, children usually present with transient ischemic attacks or strokes, which may prove more difficult to diagnose because of patient's inadequate verbal and other skills, leading to delayed recognition of the underlying moyamoya. The progression of disease can be slow, with rare, intermittent events, or it can be fulminant, with rapid neurologic decline. However, regardless of the course, it is apparent that moyamoya syndrome, both in terms of arteriopathy and clinical symptoms, inevitably progresses in untreated patients.
Surgery is generally recommended for the treatment of patients with recurrent or progressive cerebral ischemic events and associated reduced cerebral perfusion reserve. Many different operative techniques have been described, all with the main goal of preventing further ischemic injury by increasing collateral blood flow to hypoperfused areas of the cortex, using the external carotid circulation as a donor supply. This article discusses the various treatment approaches, with an emphasis on the use of pial synangiosis, a method of indirect revascularization. The use of pial synangiosis is a safe, effective, and durable method of cerebral revascularization in moyamoya syndrome and should be considered as a primary treatment for moyamoya, especially in the pediatric population.
Moyamoya; pial synangiosis; ischemia; stroke
We report the case of a 17-year-old Korean girl with systemic lupus erythematosus (SLE) who presented with sudden weakness of the right-sided extremities and dysarthria. Oral prednisolone was being taken to control SLE. Results of clinical and laboratory examinations did not show any evidence of antiphospholipid syndrome or thromboembolic disease nor SLE activity. Cerebral angiography showed stenosis of the left internal carotid artery and right anterior cerebral artery with accompanying collateral circulation (moyamoya vessels). After the patient underwent bypass surgery on the left side, she recovered from the neurological problems and did not experience any additional ischemic attack during the 14-month follow-up period. This case represents an unusual association between moyamoya syndrome and inactive SLE (inactive for a relatively long interval of 2 years) in a young girl.
Moyamoya disease; Systemic lupus erythematosus; Child
The brain MR images of 23 patients with angiographically proved moyamoya disease were reviewed to evaluate the capability of MR to demonstrate vascular and parenchymal abnormalities. All the MR images were obtained on a 2.0 T superconducting system and included T1-weighted sagittal and T2-weighted axial images without implementation of flow compensation (FC). The vascular abnormalities demonstrated on MR images were narrowing of the cavernous internal carotid artery (ICA) (73%), narrowing or occlusion of the supraclinoid ICA (87%) and proximal middle cerebral artery (MCA) (91%), and multiple collateral vessels in the basal ganglia and/or thalamus (96%). The parenchymal abnormalities included ischemic infarctions (74%), predominantly located in watershed areas, hemorrhagic infarctions (26%), intracerebral hematomas (13%), and intraventricular hemorrhage (13%). In conclusion, MR imaging was a useful diagnostic modality for detecting both vascular and parenchymal abnormalities associated with moyamoya disease. This may obviate the need for invasive angiography as far as the diagnosis is wanted at the non-quantitative level.
Whether unilateral moyamoya disease (MMD), confirmed by steno-occlusive lesion at the terminal portion of internal carotid artery with formation of moyamoya vessels unilaterally and normal or equivocal findings contralaterally, is an early form of definite (bilateral) MMD remains controversial. It is well-known that adult patients with MMD tend to suffer from cerebral hemorrhage, occasionally due to the rupture of aneurysm arising from moyamoya vessel.
A 61-year-old woman was diagnosed as unilateral MMD incidentally and followed by magnetic resonance imaging annually. Seven years after the diagnosis, cerebral aneurysm appeared on the moyamoya vessel. Before further examination, the aneurysm ruptured and resulted in massive cerebral hemorrhage.
Even in the unilateral MMD, cerebral hemorrhage may occur due to the rupture of cerebral aneurysm. Careful follow-up is recommended and early treatment is required once cerebral aneurysm is detected.
Cerebral aneurysm; Intracerebral hemorrhage; moyamoya disease; Unilateral
Moyamoya disease is a rare cerebrovascular disease characterized by stenosis or occlusion of the arteries around the circle of Willis with arterial collateral circulation. Patients with Moyamoya have significant risk for brain hemorrhage. Recognition of this disease in the patient with recurrent strokes requires a high degree of clinical suspicion.
A 57-year-old man with a past history of diabetes, hyperlipidemia and hypertension presented to the emergency department with right-sided weakness and aphasia. A head CT on admission without contrast showed a small left frontal gyrus stroke with no acute hemorrhage and he was managed medically. Laboratory testing on admission was remarkable for elevated hemoglobin A1c and LDL cholesterol. The patient's neurologic symptoms improved initially, however on Day 3 of hospitalization, the patient developed worsening of his symptoms. Physical examination was notable for a right-sided facial droop, hemiparesis in his right upper extremity, decreased strength in lower right extremity and mixed aphasia. Repeat head CT without contrast revealed a large left middle cerebral artery infarction and CTA of the neck showed multiple intracranial stenoses, specifically occlusion of the left M1 artery and moderate stenosis of the right M1 artery. Multiple collateral vessels reconstituting M2 segments were also noted, which were suspicious for Moyamoya disease. His proximal right upper extremity weakness improved mildly, but on Day 4 the patient again developed worsening right-sided weakness and a repeat head CT showed an evolving left middle cerebral artery infarction. Other stroke workup including transthoracic echocardiogram and carotid duplex ultrasound were unremarkable. He was medically managed with aspirin, atorvastatin, lisinopril, and insulin. He continued to receive speech, occupational, and physical therapy throughout his hospital stay and was transferred to an inpatient rehabilitation facility for further care after stabilization of his neurologic symptoms.
This case illustrates the clinical presentation of recurrent strokes, which is common in the context of Moyamoya disease. The diagnosis of Moyamoya disease is made with MRA or CTA which shows significant stenosis or occlusion of the cerebral arteries with a prominent collateral circulation. It is important to consider this disease in a patient with recurrent strokes because of the progressive nature of the disease and increased risk for cerebral hemorrhage.
Moyamoya disease is a disorder characterized by bilateral progressive steno-occlusion of the terminal internal carotid arteries with associated development of a fragile network of basal collateral vessels. It most commonly presents in children, but is also frequently seen in adults, especially in the third or fourth decade of life. Adults afflicted with this disease have very different clinical characteristics as compared with children. For example, adults more commonly present with hemorrhage than cerebral ischemia, while children present with cerebral ischemia nearly 75% of the time and very rarely present with hemorrhage. This significantly impacts treatment considerations for the adult-onset moyamoya patient, as cerebral revascularization, though well accepted in the context of cerebral ischemia, is relatively controversial for the prevention of rehemorrhage. The purpose of this article is to review the pertinent general features of moyamoya disease, examine the clinical characteristics associated with the adult-onset form of this disease, and provide a detailed discussion regarding the indications, operative techniques, and outcomes of direct and indirect revascularization surgical procedures.
Moyamoya disease; hemorrhage; ischemia; revascularization; adult
Moyamoya disease (MMD) is an uncommon cerebrovascular disorder characterized by progressive occlusion of the internal carotid artery causing cerebral ischemia and hemorrhage. Genetic factors in the etiology and pathogenesis of MMD are being increasingly recognized. Previous studies have shown that the RNF213 gene was related to MMD susceptibility in the Japanese population. However, there is no large scale study of the association between this gene and MMD in the Chinese Han population. Thus we designed this case-control study to validate the R4810K mutation and to define the further spectrum of RNF213 mutations in Han Chinese.
Genotyping of the R4810K mutation in the RNF213 gene was performed in 170 MMD cases and 507 controls from a Chinese Han population. The R4810K mutation was identified in 22 of 170 MMD cases (13%), including 21 heterozygotes and a single familial homozygote. Two of the 507 controls (0.4%) were heterozygous R4810K carriers. The R4810K mutation greatly increased the risk for MMD (OR = 36.7, 95% CI: 8.6∼156.6, P = 6.1 E-15). The allele frequency of R4810K was significantly different between patients with ischemia and hemorrhage (OR = 5.4, 95% CI: 1.8∼16.1, P = 0.001). Genomic sequencing covering RNF213 exon 40 to exon 68 also identified eight other non-R4810K variants; P4007R, Q4367L, A4399T, T4586P, L4631V, E4950D, A5021V and M5136I. Among them A4399T polymorphism was found in 28/170 cases (16.5%) and 45/507 controls (8.9%) and was associated with MMD (OR = 2.0, 95% CI: 1.2∼3.3, P = 0.004), especially with hemorrhage (OR = 2.8, 95% CI: 1.2∼6.5, P = 0.014).
RNF213 mutations are associated with MMD susceptibility in Han Chinese. The ischemic type MMD is particularly related to the R4810K mutation. However, A4399T is also a susceptible variant for MMD, primarily associated with hemorrhage. Identification of novel variants in the RNF213 gene further highlights the genetic heterogeneity of MMD.
Intraventricular hemorrhage long after successful encephaloduroarterio synangiosis (EDAS) is very rare. The effect of revascularization surgery for preventing hemorrhagic event of moyamoya disease remains controversial. We report a 17-year-old female with intracerebral hemorrhage and intraventricular hemorrahge 10 years after successful EDAS. Even though cerebral vessels angiography showed good collateral circulations without specific weak points, a cerebral hemorrhage could occur in patient with ischemic type of moyamoya disease long after successful indirect bypass operations. Good collateralization of cerebral angiography or magnetic resonance perfusion image after indirect bypass surgery would ensure against ischemic symptoms, not a hemorrhage. And, thus a life-time follow-up strategy might be necessary even if a good collateral circulation has been established.
Moyamoya disease; Intracranial hemorrhage; Perfusion; Ischemic attack
We report a rare case of Williams syndrome accompanying moyamoya disease in whom postoperative global cerebral infarction occurred unpredictably. Williams syndrome is an uncommon hereditary disorder associated with the connective tissue abnormalities and cardiovascular disease. To our knowledge, our case report is the second case of Williams syndrome accompanying moyamoya disease. A 9-year-old boy was presented with right hemiparesis after second operation for coarctation of aorta. He was diagnosed as having Williams syndrome at the age of 1 year. Brain MRI showed left cerebral cortical infarction, and angiography showed severe stenosis of bilateral internal carotid arteries and moyamoya vessels. To reduce the risk of furthermore cerebral infarction, we performed indirect anastomosis successfully. Postoperatively, the patient recovered well, but at postoperative third day, without any unusual predictive abnormal findings the patient's pupils were suddenly dilated. Brain CT showed the global cerebral infarction. Despite of vigorous treatment, the patient was not recovered and fell in brain death one week later. We suggest that in this kind of labile patient with Williams syndrome accompanying moyamoya disease, postoperative sedation should be done with more thorough strict patient monitoring than usual moyamoya patients. Also, we should decide the revascularization surgery more cautiously than usual moyamoya disease. The possibility of unpredictable postoperative ischemic complication should be kept in mind.
Moyamoya disease; Williams syndrome; Postoperative infarction; Ischemic complication
The incidence of symptomatic hyperperfusion syndrome after superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis for patients with moyamoya disease (MMD) approaches 30%. In most cases, hyperperfusion occurs in a localized area and disappears within 1-2 weeks.
A 59-year-old female diagnosed with asymptomatic MMD for 4 months became rapidly symptomatic with transient ischemic attacks (TIAs). After left STA-MCA anastomosis surgery, she developed symptomatic hyperperfusion, initially (1-2 weeks after surgery) manifesting with severe headache and lesions located in the left basal ganglia. She then developed (2-5 weeks after surgery) aphasia and right hemiparesis caused by new hyperperfusion lesions located in the left frontal area. At discharge (7 weeks after surgery), she recovered fully without any remaining neurologic deficit and no ischemic lesions.
This report details a rare case of a patient with MMD who presented with regionally progressive hyperperfusion lesions after STA-MCA anastomosis and symptoms that persisted for 5 weeks following surgery. Results from this case suggest that regional differences exist in the functional recovery of cerebrovascular reactivity (CVR) in a patient with rapidly progressive MMD.
Cerebral hyperperfusion; moyamoya disease; STA-MCA anastomosis
Moyamoya disease is a rare cerebral vasculopathy characterised by progressive narrowing of the major intracranial vessels and development of collateral vessels. Clinically, it presents with cerebral ischaemic or haemorrhagic events, with eventual severe morbidity and mortality. A 10-year-old girl presented with episodic vascular headache and transient left sided hemiparesis, which persisted for a few hours and was clinically labelled as sporadic hemiplegic migraine according to International Headache Society criteria. We investigated all possible causes of unusual headache. Cerebral digital subtraction angiogram was carried out and moyamoya disease was finally diagnosed.
Moyamoya disease is a cerebrovascular disorder of unknown cause, characterized by slowly progressive bilateral stenosis or occlusion of the internal carotid arteries and produces collateral vessels. Moyamoya syndrome has rarely been reported in association with Graves' disease, especially in children. Several reports suggest that a cerebral infarction might have occurred in patients with clinical and laboratory evidence of hyperthyroid function. We report a case of Moyamoya disease in a girl with Down syndrome and thyrotoxicosis, and we review the relevant literature. To our best knowledge, this is the first report of Moyamoya disease associated with thyrotoxicosis in a young person in Korea.
Moyamoya disease; thyrotoxicosis; Down syndrome
We sought to review the current literature with regards to future risks of hemorrhage following cerebral revascularization in Moyamoya disease (MMD).
We performed a comprehensive literature review using PubMed to inspect the available data on the risk of hemorrhage after revascularization in MMD.
In this review, we identify the risk factors associated with hemorrhage in MMD both before and after cerebral revascularization. We included proposed pathophysiology of the hemorrhagic risk, role of the type of bypass performed, treatment options, and future needs for investigation.
The published cases and series of MMD treatment do show a risk of hemorrhage after treatment with either direct or indirect bypass both in the immediate as well as long-term future. While there are no discernible patterns in the rate of these hemorrhages, there is Class III evidence for the predictive effect of multiple microbleeds on preoperative imaging. Also, whereas revascularization, both direct and indirect, has been shown to reduce ischemic complications from MMD, there is not an association with the risk of hemorrhage after the procedure. Further studies need to be performed to help evaluate what the risk factors are and how to counsel patients as to the long-term outlook of this disease process.
Angioarchitecture; cerebral hemorrhage; cerebral perfusion; moyamoya
A case of unilateral moyamoya disease is reported in an adult, associated with an aneurysm of the circle of Willis and a nonfunctional pituitary adenoma. A review of the literature is discussed. Young individuals presenting with signs of acute cerebrovascular changes of undetermined cause should be evaluated for moyamoya disease.
Hemorrhagic type of moyamoya disease (MMD) is extremely rare in children. Ischemia following hemorrhage is very rare in MMD. There are only 11 reports of mixed-type of MMD, with the patient having both hemorrhage and ischemia in the same hemisphere at the time of presentation, or at different time periods. The ischemia is usually secondary to a precipitating cause. However, there are no reports of a child presenting with both ischemia and hemorrhage in different hemispheres. We present a previously unreported phenomenon of MMD, presenting as hemorrhage and ischemia in opposite hemispheres and review the relevant literature.
Hemorrhage; ischemia; mixed type; moyamoya disease; pediatric
The authors present a rare case of adult moyamoya disease in which a patient experienced rapid progression of cerebral infarction after intraventricular hemorrhage (IVH). A healthy 39-year-old woman was admitted to our hospital with sudden headache, a decreased level of consciousness and mild tetraparesis. Initial magnetic resonance imaging revealed small cerebral infarction and IVH. Although the patient underwent conservative therapy including hypervolemia, hemodilution, keeping moderate hypertension and administration of a free radical scavenger, she showed a fulminant clinical course of cerebral infarction. The authors discuss the possible pathophysiology and suggest the treatment for such cases.
Moyamoya disease; Cerebral infarction; Intraventricular hemorrhage
Moyamoya disease (MMD) is a cerebrovascular disease characterized by progressive stenosis or occlusion of the terminal portion of internal carotid arteries and the formation of a vascular network at the base of the brain. The pathogenesis of MMD is still unclear.
We retrospectively analyzed clinical data for 65 consecutive patients with MMD in our institutions and evaluated the histopathological and immunohistochemical findings of intracranial vessels from 3 patients. The onset age distribution was found to have 1 peak at 40–49 year-old age group, no significant difference was observed in the female-to-male ratio (F/M = 1.2). Intracranial hemorrhage was the predominant disease type (75%). Positive family history was observed in 4.6% of patients. Histopathological findings were a narrowed lumen due to intimal fibrous thickening without significant inflammatory cell infiltration, and the internal elastic lamina was markedly tortuous and stratified. All 3 autopsy cases showed vacuolar degeneration in the cerebrovascular smooth muscle cells. Immunohistochemical study showed the migration of smooth muscle cells in the thickened intima, and aberrant expression of IgG and S100A4 protein in vascular smooth muscle cells. The Complement C3 immunoreactivity was negative.
This study indicated that aberrant expression of IgG and S100A4 protein in intracranial vascular wall of MMD patients, which suggested that immune-related factors may be involved in the functional and morphological changes of smooth muscle cells, and finally caused the thickened intima. A possible mechanism is that deposits of IgG in the damaged internal elastic lamina may underlie the disruption of internal elastic lamina, which facilitated S100A4 positive SMCs migrated into intima through broken portions of the internal elastic lamina, resulting in lumen stenosis or occlusion, leading to compensatory small vessels proliferation.