multiple simultaneous intracerebral hemorrhages ( msih ) is rare phenomenon , accounting for ~3% of all intracranial hemorrhage events ( 1 ) . msih remains intriguing regarding the causes and mmd can be caused by a variety of factors , including hypertension , cerebral vasculitis , sympathetic nerve stimulants , drugs that affect blood coagulation , brain tumors , cerebral amyloidosis , venous sinus thrombosis and coagulation disorders , in addition to other unexplained factors ( 2,3 ) . the treatment for msih mainly consists of releasing the intracranial pressure caused by the hematoma , identifying the cause of the original hemorrhage and then providing surgical treatment ( 4 ) . although there are numerous studies describing msih in the literature , msih of moyamoya disease ( mmd ) is rare . kikuta et al ( 5 ) in 2008 reported a series of multiple intracerebral hemorrhages of mmd , but these hemorrhages were limited to multiple trace bleeding . however , to the best of our knowledge , no case of severe msih caused by mmd has been reported to date . mmd is an uncommon disease characterized by progressive occlusion of the terminal portion of the internal carotid artery and its main branches within the circle of willis . this occlusion results in the formation of a fine vascular network at the base of the brain . these mmd vessles are fragile and easy to rupture ( 6 ) ; therefore , msih in mmd is possible . intracranial hemorrhage in mmd is not easy to treat ( 7 ) , so msih would be more difficult to treat . the present study reports a rare case of severe msih caused by mmd , which was treated with hematoma evacuation and decompressive craniectomy , resulting in good recovery . in addition to the case report , the mechanism of mmd - induced msih is also discussed . written informed consent was obtained from the patient . a 40-year - old female patient with no history of hypertension and diabetes mellitus was admitted the first hospital of jilin university ( changchun , china ) in june 2015 due to presentation of sudden severe headache and vomiting followed by gradual coma for 2 h. physical examinations revealed stable vital signs with a blood pressure of 140/90 mmhg , and the neurological examination showed minor coma ( glasgow coma scale score , 11 ) ( 8) , right hemiplegia , degree 3 muscle strength , positive babinski sign , and stiffness in the neck with kernig 's sign ( 9 ) . cranial computed tomography ( ct ) revealed multiple irregular high density zones in the left basal ganglia , posterior temporal lobe and frontal lobe , with mild peripheral edema . the left ventricle showed deformation under compression , with the midline shifted to the right ( fig . cranial ct angiography ( cta ) subsequent to admission demonstrated that the normal vascular morphology in the area of the bilateral middle cerebral artery was disrupted , with visible hematomas in the maximum intensity projection axis ( fig . 2 ) . based on the symptoms and the radiographic examination findings , a clear diagnosis of mmd and intracerebral msih was established . an emergency hematoma evacuation and decompressive craniectomy was scheduled . to further clarify the circumstances of the intracranial arteries , preoperative digital subtraction angiography ( dsa ) was performed under general anesthesia in the catheterization room . the dsa results showed occlusions at the ends of the bilateral carotid arteries , which were replaced with 3 ) . with the exception of these smoke - like blood vessels , no aneurysms or vascular malformations were observed in the areas of the left middle cerebral artery or anterior artery areas ( fig . hematoma evacuation and decompressive craniectomy were performed under general anesthesia in order to remove the majority of the hematoma in the left basal ganglia and posterior temporal lobe ; however , the hemorrhage in the left frontal lobe was not treated as it was risky and unnecessary . following hematoma evacuation , the temporal muscle was attached to the brain surface for fusion . a postoperative ct scan revealed that the majority of the intracranial hematoma was removed and that the ventricular size had returned to normal , with the midline in the center ( fig . 4 ) . postoperative nutritional support , including nutrison fibre ( 80 ml / h intranasally ; nutrica pharmaceutical co. , ltd . , wuxi , china ) and trimebutine maleate ( 400 mg once every three days ; tanabe pharmaceutical co. , ltd . , tianjin , china ) , and symptomatic treatment were provided for 1 week , and the patient gradually regained consciousness , with motor aphasia , low pressure in the left decompression window , right hemiplegia and degree 3 muscle strength . over the 3-month follow - up period the patient was aphasic , with degree 4 muscle strength in her right limb , and essentially self - sufficient in her daily life . in june 2016 , the patient 's symptoms persisted but no hemorrhage had reoccurred , and the patient 's quality of life was good . intracerebral hematoma commonly occurs at a single site , although multiple hemorrhages at different sites with long intervals may also occur . by contrast , the incidence of msih is very rare . in 2010 , stemer et al ( 10 ) conducted a study including 522 cases of spontaneous intracerebral hemorrhage , of which 29 were msih patients , yielding an incidence rate for msih of 5.6% . msih is defined , based on imaging examination , as multiple hemorrhages or hemorrhages at different sites occurring within 24 h , including secondary hemorrhages with clear causes and an unexplained primary hemorrhage ( 10 ) . the incidence of simple primary msih was estimated to be between 0.75 and 3.0% , which is lower compared with the overall incidence of msih ( 10 ) . however , the study by stemer and colleagues did not include mmd cases , possibly due to the majority of mmd - induced msih cases not being clearly identified and classified as primary msih . indeed , only a limited number of mmd - induced multiple intracerebral hemorrhage cases were available in the literature . in 2014 , laiwattana et al ( 3 ) reviewed the msih literature published during the 60-year period between 1953 and 2013 , and their results were consistent with the msih incidence rate reported by stemer et al ( 10 ) . in addition , the authors reviewed the literature in order to analyze the causes of secondary msih , although mmd was not considered as a cause of secondary msih in their review ( 3 ) . in the present study , a case of msih caused by mmd was described , aiming to bring clinical attention to the fact that mmd can lead to msih , thereby enriching the available clinical data of msih . in addition to unexplained primary factors , numerous secondary factors can cause msih , including arterial diseases , venous drainage obstruction , parenchymal diseases ( such as brain tumors and cavernous hemangioma ) , drug use and hematologic diseases ( 4,11,12 ) . however , the most common causes are arterial diseases , such as hypertension , atherosclerosis , vasculitis and cerebral amyloidosis . in 2005 , yen et al ( 13 ) reported 1,306 cases of hypertensive intracerebral hemorrhage , including 10 cases of msih , with an incidence rate of ~0.8% . for instance , in the study by mccormick and rosenfield ( 2 ) published in 1973 , 2 cases of msih were clearly caused by vasculitis among 144 cases of cerebral hemorrhage ( 2 ) . in addition , cerebral amyloidosis may cause msih ; for example , in 1984 , gilles et al ( 14 ) reported 11 cases of msih that were directly caused by cerebral amyloidosis . msih caused by arterial disease most likely occurs due to multiple ruptures in the diseased vessels , induced by hypertension from the original arterial disease . alternatively , ruptures and hemorrhages in a diseased cerebral vessel may lead to a transient increase in blood pressure , thereby inducing hemorrhages at other sites in the brain , resulting in msih ( 15,16 ) . mmd is an arterial brain disease that is characterized by occlusions at the end of the intracranial and carotid arteries . normal blood vessels disappear and are replaced by  smoke - like blood vessel hyperplasia , mainly from expanded and distorted lenticulostriate and thalamoperforate arteries ( 17 ) . in these abnormal small arteries , internal elastic layer fracture , medial fibrosis and local expansion to form small aneurysms may occur ( 18,19 ) . theoretically , these small diseased arteries are able to cause msih through hypertension , or through hemorrhage at one site that can lead to a transient increase in blood pressure and induce hemorrhages at other sites . however , msih caused by mmd has been rarely reported , and the few published studies were limited to multiple trace bleeding ( 20 ) . for instance , the study of kikuta et al ( 5 ) in 2008 investigated 50 cases of mmd using 3 t magnetic resonance imaging ( mri ) , and identified 11 cases of multiple trace bleeding , which were caused due to small diseased arteries . by contrast , mmd - induced msih has not been previously described , and was first reported in the present study . the cranial ct performed in the present study demonstrated no intracranial malacia , which may occasionally form subsequent to hemorrhage . one of the pathological changes caused by mmd is that certain small arteries become fragible , which manifests as internal elastic layer fracture and medial fibrosis . the rupturing and hemorrhaging of a diseased cerebral vessel may lead to a secondary transient increase in blood pressure , thereby inducing hemorrhages at other sites in the brain and resulting in msih . following msih , the underlying cause must be identified in order to develop an effective treatment plan . the causes of msih include arterial diseases , clogging of venous drainage , parenchymal diseases , drug use and hematologic diseases ( 3 ) . therefore , specific examinations can be performed , including the following : cta , mra or dsa to examine the arteries ; ctv , mrv , or dsa to examine the intracranial veins ; ct and mri for brain parenchymal lesions ; and routine blood tests for determination of platelet count , platelet function , coagulation function and blood cell sedimentation rate , in order to identify hematologic diseases ( 4 ) . in addition , the medical history of the patient , including hypertension , diabetes and drug use involving sympathetic stimulants and anticoagulants , is also important . however , mmd diagnoses are primarily dependent on imaging studies . for patients with acute cerebral hemorrhage , cta is a rapid and effective method to correctly diagnose mmd ( 21,22 ) , although examination by dsa may provide more accurate results . the case reported in the present study was accurately diagnosed as mmd and msih by cta following the onset , while laboratory tests ruled out hematologic diseases . however , treatment differs from that for single intracranial hemorrhage , primarily because multiple hemorrhages can be scattered , and not all multiple hemorrhages can be removed at the same time . for instance , in the current study , only the hematomas in the left basal ganglia and the posterior temporal lobe were removed , while the hemorrhage in the frontal lobe was not treated as it was risky and unnecessary , although simultaneous decompressive craniectomy was performed . the efficacy of msih treatment was not better over that for a single hemorrhage ( 23 ) . the study by laiwattana et al ( 3 ) reported that the prognosis for msih was poor , particularly for cases involving the bilateral thalamus . the case reported in the current study involved only the hemisphere on the left side of the meninges . compared with msih cases involving both hemispheres , therefore , considering the present report of mmd - induced msih , we suggest that the possibility of mmd should be considered when an msih case is identified . in clinical practice , mmd can be accurately diagnosed using cta and may lead to pathological changes in small arteries , causing them to become fragible . rupture and hemorrhage occurring at one site may induce a transient increase in blood pressure , causing the rupture of small arteries at other sites , and thus leading to msih . subsequent to ruling out disorders of the blood and blood coagulation , hematoma evacuation and decompression should be performed in selective cases , which can lead to good prognosis . in conclusion , msih caused by mmd is extremely rare ; microbleedings are typical of msih , and severe msih rarely occurs . the cause of severe msih may be a result of transient hypertension following a hemorrhage , and the hypertension can result in simultaneous hemorrhages in other locations . in the present study , the treatment of msih was difficult , primarily because hemotomas were scattered and damaged numerous functional regions of the brain .
multiple simultaneous intracerebral hemorrhages ( msih ) caused by moyamoya disease ( mmd ) is extremely rare . to date , the clinical manifestations , imaging characteristics and mechanism of mmd - induced msih have not yet been elucidated . in order to improve the understanding on such cases , the present study described a rare case of msih caused by mmd . a 40-year - old female patient with no history of hypertension or diabetes mellitus experienced a sudden headache followed by coma . 
 cranial computed tomography ( ct ) examination revealed msih in the left frontal area , temporal lobe and basal ganglia . 
 ct angiography and digital subtraction angiography examinations revealed typical characteristics of mmd . 
 subsequent to excluding disorders of the blood system and blood coagulation , we concluded that the present case of msih was caused by mmd . 
 hematoma evacuation and decompressive craniectomy were performed with satisfactory results . 
 in addition , after reviewing previous msih cases in the literature , potential mechanisms of mmd - mediated msih were considered . in conclusion 
 , mmd should be considered as a possible cause of msih during diagnosis and treatment . 
 mmd can lead to pathological changes in the fragility of small arteries ; therefore , rupture and hemorrhage at one site may induce a transient increase in blood pressure , causing the rupture of small arteries at other sites , and thus leading to msih . 
 hematoma evacuation and decompression should be conducted in selective cases of mmd - induced msih in order to achieve a good prognosis .