Recovery from primary pontine hemorrhage

Tegmental Pontine Hemorrhages: Clinical Features and Prognostic Factors

We report six patients with partial, predominantly paramedian, tegmental pontine hemorrhages. Constant clinical manifestations consisted of: ipsilateral miosis, horizontal gaze paresis, lower motor neuron facial paresis, contralateral hemisensory loss and mild and transitory hemiparesis, dysarthria and mild or no compromise of consciousness. Five out of six were hypertensive. All patients survived with mild sequelae, oculomotor disturbances being the most persistent deficit. We found in our patients that a transverse diameter of less than 17 mm, unilaterality of the injury and absence of coma were the major indicators of a favorable outcome.

Evaluation of the hematoma consequences, neurobehavioral profiles, and histopathology in a rat model of pontine hemorrhage

OBJECT

Primary pontine hemorrhage (PPH) represents approximately 7% of all intracerebral hemorrhages (ICHs) and is a clinical condition of which little is known. The aim of this study was to characterize the early brain injury, neurobehavioral outcome, and long-term histopathology in a novel preclinical rat model of PPH.

METHODS

The authors stereotactically infused collagenase (Type VII) into the ventral pontine tegmentum of the rats, in accordance with the most commonly affected clinical region. Measures of cerebrovascular permeability (brain water content, hemoglobin assay, Evans blue, collagen Type IV, ZO-1, and MMP-2 and MMP-9) and neurological deficit were quantified at 24 hours postinfusion (Experiment 1). Functional outcome was measured over a 30-day period using a vertebrobasilar scale (the modified Voetsch score), open field, wire suspension, beam balance, and inclined-plane tests (Experiment 2). Neurocognitive ability was determined at Week 3 using the rotarod (motor learning), T-maze (working memory), and water maze (spatial learning and memory) (Experiment 3), followed by histopathological analysis 1 week later (Experiment 4).

RESULTS

Stereotactic collagenase infusion caused dose-dependent elevations in hematoma volume, brain edema, neurological deficit, and blood-brain barrier rupture, while physiological variables remained stable. Functional outcomes mostly normalized by Week 3, whereas neurocognitive deficits paralleled the cystic cavitary lesion at 30 days. Obstructive hydrocephalus did not develop despite a clinically relevant 30-day mortality rate (approximately 54%).

CONCLUSIONS

These results suggest that the model can mimic several translational aspects of pontine hemorrhage in humans and can be used in the evaluation of potential preclinical therapeutic interventions.

Benign brainstem hemorrhage

Most patients with brainstem hemorrhage have a poor prognosis. There are occasional reports of a favorable outcome with hematomas restricted to the mid-brain region. We report two patients with hematomas within the lower brainstem (pons and medulla) who made a good recovery. Diagnosis was unsuspected until the cranial CT scan was done. Angiography was normal in both cases. Recovery was excellent in one and fair in the second patient. Patients with medullary hemorrhage are at risk for aspiration and may suddenly develop respiratory arrest and therefore should be carefully observed. Our review of the literature suggests that with some small brain-stem hemorrhages recovery is good to excellent and recurrences are rare.

Surgical management of brain stem vascular malformations

Vascular malformations of the brain stem are a histologically heterogenous collection of lesions which most often present with sudden and progressive neurologic deficit related to haemorrhage. Since 1987 the authors have treated eleven cases of brain stem vascular malformation. Seven of the patients were treated with complete surgical extirpation of the haematoma and malformation because of progressive neurologic deficit. Four additional patients made a full neurologic recovery and are being carefully observed for signs suggestive of the need for surgical treatment. Complete surgical excision of brain stem vascular malformations is mandatory for patients with progressive neurologic deficit related to recurrent haemorrhage.

[Primary hematoma of the brain stem: considerations apropos of a case]

The case of a 48 year-old woman presenting with a primary pontine hematoma is reported. The clinical evolution simulated a brain stem tumor and the diagnosis of hematoma was not established before the operation. The preoperative neurological deficit improved except for a facial nerve palsy. These hematomas are thought to be due to rupture of "cryptic" arteriovenous malformations and should be differentiated from those secondary to systemic hypertension. The diagnosis of brain stem hematomas should be considered in any case of brain stem lesion, especially in young and normotensive patients.

Primary pontine hemorrhage: clinico-computed tomographic correlations

A series of 10 patients with primary pontine hemorrhage with CT confirmation is reported. All patients were hypertensive. Seven patients had classical pontine hematoma syndrome characterized by decreasing levels of consciousness, quadriparesis, and eventual demise. The three other patients had atypical or partial clinical features of pontine hemorrhage and good prognosis. The pontine hemorrhage can be divided into 4 groups from the viewpoint of location of the hematomas. There are bilateral tegmentobasis (massive) type, hemipontine type, localized tegmentum type, and localized basis type. There was no evidence of ventricular extension in all 10 cases. All patients suffering the massive type had classical pontine hematoma syndrome and fatal outcome, the other three remaining types had atypical or partial clinical features for pontine hemorrhage and survived. It is concluded that CT is highly reliable method for the diagnosis and location of primary pontine hemorrhage.

Brainstem haematomas: review of the literature and presentation of five new cases

Fifty-one cases of brainstem haematoma that have undergone neurosurgical intervention since Finkelnburg's first exploration in 1905, are presented, together with five new cases. The location, incidence, aetiological and pathological factors, as well as clinical syndromes are reviewed. Diagnostic criteria are presented. The distinction between brainstem "haematoma" and "haemorrhage" is stressed. A retrospective comparison of 56 surgically treated cases and 31 conservatively managed cases is made, as is an analysis of the natural history of the disease process. Based on currently available data, the conclusion is drawn that patients with brainstem haematomas fare quite well after surgical therapy.

Lateral pontine hemorrhage: reappraisal of benign cases

We reviewed 6 computed tomography-documented cases of primary lateral pontine hemorrhage that occurred in our two institutions over a 2-year period. All patients survived the acute stroke, with excellent functional recovery in 4. The level of consciousness of the patient and the size of the hemorrhage had no consistent bearing on outcome. Both of these features have been considered important prognostic indicators in patients with pontine hemorrhage, but in our series benign outcomes were not restricted only to patients who were alert or had small hemorrhages; on the other hand, severe disability was noticed in 1 patient with a small hematoma strategically located in the pontine tegmentum. Our observations suggest that, although some patients with lateral pontine hemorrhage have a good prognosis, there is no single determinant that predicts outcome in a given patient.

Acute direct and indirect lesions of the brain stem--CT findings and their clinical evaluation

Since the introduction of computer tomography (CT) (Ambrose 1973, Hounsfield 1973) it has become an essential instrument in the diagnosis of acute intracranial lesions. The precise analysis of the CT and in particular the evaluation of the basal cisterns, yields results which are already wellknown, basically, from post-mortem investigations and clinical findings. However, while these were retrospective analyses and results, serial CT examinations which are free of risk for the patient and can be used in correlation with the clinical neurological findings, allow important assertions intra vitam, as well as a definitely better assessment of the prognosis. In addition to acute supratentorial lesions, acute and subacute infratentorial lesions are analysed and their clinical significance described. In this way, for the first time, the dynamics of the mechanical factors in raised intracranial pressure can be analysed. Important conclusions are drawn for the clinical management of the patients, and even some new indications for operation. Analysis of the acute hyperdense brain stem lesions--pathognomonic for haemorrhages--allows for the first time the diagnosis and continuous observation of traumatic and secondary haemorrhages caused by raised pressure, as well as spontaneous ones. As regards the mortality and morbidity, the results in this large series of traumatic and secondary haemorrhages are in striking contrast to previous analyses based on post mortem findings. Acute hypodense brain stem lesions are not amenable to any definite pathogenetic classification--softening, inflammatory lesions, tumours and oedema must all be considered. With acute lesions we are only dealing with infarcts, which are only incompletely assessable in the computer tomogram, and their diagnosis must still depend on the clinical findings. Secondary ischaemic lesions in acute raised intracranial pressure are identifiable in over 18% as infarcts which involve the entire territory of an artery. These additional space-occupying lesions are only survived by 11% of the patients. Hence the correlation which has been established between the basal cisterns and intracranial pressure is of great clinical significance. From our own research group several reports on different aspects of raised intracranial pressure and lesions of the brain stem have appeared since 1979. Similar analyses of partial aspects of the basal cisterns, have been published only recently, and came essentially to the same conclusions.

Brainstem haematoma due to presumed cryptic telangiectasia

Three patients with primary brainstem haematoma are reported. The clinical presentation suggested an initial diagnosis of pontine tumour in two and demyelination in one patient. The subacute course is characteristic of brainstem haematoma due to presumed cryptic telangiectasia, the abnormal vessels being destroyed by the haemorrhage. These findings emphasise the importance of considering haematoma due to cryptic telangiectasia in the differential diagnosis of subacute brainstem lesions.

Normal mental state despite bilateral pontine tegmental hemorrhage

Alertness was preserved in a 47-year-old hypertensive man who acutely develop headache, cranial nerve abnormalities, weakness and dysmetria. Computerized tomography revealed a bilateral pontine tegmental hemorrhage. This is the first well-documented case of bilateral pontine tegmental hemorrhage with a completely normal mental status.

Surgical treatment of cryptic AVM's and associated hematoma in the brain stem and spinal cord

Most surgically treated cases of brain-stem hematomas have been attributed to rupture of cryptic arteriovenous malformations (AVM's); however, very few cases have been histologically proven. Similarly, there are very few reports of surgically treated spontaneous hematomyelia, in which the hemorrhage has been histologically confirmed as being due to a purely intramedullary AVM. The authors report three cases with surgically treated, histologically confirmed AVM's, of which two were in the brain stem and the third was in the spinal cord. In all these cases, abnormal vascular tissue in the wall of the hematoma cavity was recognized at operation and excised.

Primary pontine haemorrhage: clinical and computed tomographic correlations

The clinical and computerised tomographic findings in 40 patients with primary pontine haemorrhage were reviewed. Twenty-nine patients were hypertensive. Four patients had angiographic or necropsy evidence of vascular malformations. In 33 cases, there was rapid deterioration to maximal neurological deficit; whereas in seven cases, there was sudden onset but subsequent progression to maximal deficit 24 hours to 5 days following the initial ictus. Seven patients had clinical features considered atypical for pontine haemorrhage. Five patients survived and four of these were capable of performing activities of daily living within 3 months of the haemorrhage. In all cases CT showed a hyperdense non-enhancing brain stem haematoma. There was evidence of ventricular extension in 27 cases. There was CT evidence of subarachnoid blood in only two patients who also had vascular malformations. In 26 cases, there was CT evidence that the haematoma extended to the midbrain and in four cases to the thalamic region. In six cases CT was repeated 6 to 21 days after the initial scan and it showed resolution of the haematoma in size and density; none of the haematomas showed post-contrast enhancement on initial or follow-up CT.

Brain-stem haematoma with complete recovery

A case of CT-diagnosed brain-stem haematoma associated with signs of dorsal medullary involvement is reported. The patient recovered completely within 1 month.

Pontine haemorrhage: a clinical analysis of 26 cases

Correlation with the size of the haematoma, neurological findings and prognosis was studied in 26 cases of hypertensive pontine haemorrhage, using CT. A good prognosis was found with no or mild disturbance of consciousness, normal pupils, and transverse diameter of the haematoma 20 mm or less. Most of the patients with poor prognosis became comatose within two hours of onset. Their pupils were dilated bilaterally, pin-point or anisocoric and the transverse diameter of the haematoma was over 20 mm.

Successful stereotaxic evacuation of an acute pontomedullary hematoma. Case report

A healthy young woman developed a rapidly progressive pontomedullary lesion 24 hours after delivery of her first child. The lesion was shown on computerized tomography (CT) to be a primary hematoma. Stereotaxic aspiration was carried out, and the patient recovered. Angiography and CT scanning demonstrated a vascular lesion compatible with an arteriovenous malformation.

Prognostic evaluation of brainstem hematomas: the role of CT scan and brainstem auditory evoked potentials

6 cases of brainstem hematoma were studied utilizing CT scan and brainstem auditory evoked potential (BAEP) recordings. CT scan did not contribute to an early discrimination between primary and secondary hematomas. Size of the hematoma and the presence of blood in the CSF did not represent evident signs in differentiating benign from unfavourable brainstem hematomas or hemorrhages. BAEP recordings showed the presence of electrophysiological anomalies at the level of the lesion, demonstrating that bleeding as well as tumor in the brainstem can provoke a focal damage.

Pain and hyperpathia in pontine haemorrhage

A 56-year-old man had acute onset of left sided weakness, spontaneous pain and hyperpathia in the left limbs. CT demonstrated a small pontine haemorrhage, in the floor of the fourth ventricle.

Clinicopathological study of pontine hemorrhage

This report concerns a clinico-pathological study of 60 patients afflicted with primary pontine hemorrhage. The illness was fatal in 43, 17 patients survived. Ophthalmic signs, autonomic disturbances and transient visual hallucination were observed and discussed. A ruptured microaneurysm within the border of a pontine hematoma was detected in this study, and in the first report of such a finding.

Pontine hematomas

Pontine hematomas are very rare lesions that in the past were found at postmortem examination rather than diagnosed from the clinical presentation. The advent of computed tomography allowed more frequent identification of those lesions which has shown a more favorable prognosis than formerly thought. Three patients suffering from intrapontine hematomas, revealed by computed tomography, are discussed. The etiopathogenesis, location, and clinical features of this lesion are discussed in an attempt to establish general criteria from adequate management. All 3 patients (2 treated conservatively and 1 by surgical evacuation) had a successful outcome. Repeat CT scans gave evidence of resolution of this lesion in all patients.

Recovery following brainstem hemorrhage

Two patients made virtually complete recoveries following hemorrhage within the brainstem. Progressive clinical deterioration in each case was managed surgically by evacuation of the hemorrhagic lesion in 1 case and treatment of secondary hydrocephalus in both. Computerized tomographic scanning proved essential for nonsurgical diagnosis and later management.

Benign brainstem hematoma

Brainstem hematoma is generally considered a very rare condition with a grave prognosis. This report presents two patients with extensive brainstem hematomas who both recovered without major sequele. A brainstem hematoma is often impossible to differentiate from an infarction despite angiographic and cerebrospinal fluid examinations, but is readily disclosed by computerized tomography. It is suggested that the seriousness of the prognosis in brainstem hematoma may earlier have been exaggerated as there may have been a tendency to classify cases exhibiting a good recovery as infarcts, while the diagnosis hematoma was reserved for cases verified at autopsy.