Bilateral Hypertrophic Olivary Degeneration after Pontine Hemorrhage: A Case Report

BACKGROUND

Hemorrhage lesions may lead to bilateral hypertrophic olivary degeneration (HOD) through interruption of the dentato-rubral-olivary pathway. The pathological features of HOD are unusual neuronal trans-synaptic degenerative changes.

CASE SUMMARY

A 56-year-old female was admitted to our hospital because her lower extremities and left upper ones were unable to move for 3 mo, and the swelling of her right lower extremities became worse 3 days ago. She had a hypertension history. Her characteristic clinical manifestations are palatal myoclonus and nystagmus. The patient’s magnetic resonance imaging (MRI) results showed that she had bilateral HOD after an acute pontine hemorrhage. She was given symptomatic and supportive treatment. The gabapentin, the memantine and the trihexyphenidyl were taken twice a day each. The rehabilitation and psychotherapy were implemented. After 3 months of treatment, her eye symptoms improved.

CONCLUSION

Bilateral HOD is a rare phenomenon after pontine hemorrhage. The key to diagnosis lies in the clinical manifestations and MRI results.

Right Tegmental Hemorrhage with Urinary Retention: A Case Report

The upper brainstem tegmentum is dense and complex, making it difficult to localize functions to specific subregions. In particular, the precise location and possible laterality of subregions supporting basic functions like consciousness and urinary continence remain unclear. Here, we describe a patient who presented with a right pontine tegmental syndrome caused by intraparenchymal hemorrhage. Despite hemorrhage extension into the fourth ventricle and expansion of both hemorrhage and edema into a large region of the caudal midbrain and right-sided pontine tegmentum, this patient did not lose consciousness. Instead, he developed new and total urinary retention, with residual bladder volumes of more than 1,000 mL. We conclude that injury to the right pontine tegmentum is sufficient to disrupt the micturition reflex pathway.

Effects of injuries to descending motor pathways on restoration of gait in patients with pontine hemorrhage

BACKGROUND AND PURPOSE

Gait disturbance due to injuries of the descending motor pathway, including corticospinal tract (CST), corticoreticular pathway (CRP), and medial and lateral vestibulospinal tracts (VSTs), are commonly encountered disabling sequelae of pontine hemorrhage. We investigated relations between changes in the CST, CRP, and medial and lateral VST and corresponding changes in gait function in patients with pontine hemorrhage.

METHOD

Nine consecutive stroke patients with pontine hemorrhage, and 6 age-matched normal subjects were recruited. Four patients were allocated to group A (can't walk independently) and 5 to group B (can walk independently). Diffusion tensor imaging (DTI) data were acquired twice at acute to subacute stage and chronic stage after stroke onset. Diffusion tensor tractography (DTT) was used to reconstruct CST, CRP, medial and lateral VST.

RESULT

The CRP shows a significantly different between groups A and B in both initial and follow up DTT (p > 0.05). In contrast, CST, medial VST and lateral VST did not show a significant difference (p > 0.05). Regarding DTI parameters of CRPs in group A, percentages of patients with fractional anisotropy (FA) and mean diffusivity (MD) values more than two standard deviation from normal were higher by follow up DTI than by initial DTI, however, the CRPs in group B only showed increased abnormal range of MD.

CONCLUSIONS

The CST does not play an essential role in recovery of independent walking and vestibulospinal tracts may not crucially affect recovery of independent walking in patients with pontine hemorrhage. In contrast, and intact CRP or changes of the CRP integrity appear to be related to the recovery of gait function.

Hypertrophic Olivary Degeneration and Holmes Tremor: Case Report and Review of the Literature

BACKGROUND

Hypertrophic olivary degeneration (HOD) is very rare type of degeneration that causes hypertrophy rather than atrophy. The classical presentation of HOD is palatal myoclonus. However, HOD may rarely present with Holmes tremor (HT). HT is unusual symptomatic tremor characterized by combination of rest and intention tremor. It has been reported in small case series, so far.

CASE DESCRIPTION

In this study, a man aged 62 years with HOD and HT spreading to the upper and lower extremities after pontine-midbrain hemorrhage due to cavernoma was presented.

CONCLUSIONS

Although pontine-midbrain hemorrhage may cause HT in the late period, HOD can be revealed on magnetic resonance imaging. Tract anatomy, especially the Guillain-Mollaret triangle, should be considered to explain the relationship between HT and HOD.

Pendular Oscillation and Ocular Bobbing After Pontine Hemorrhage

The pathophysiology of acute, vertical spontaneous eye movements following pontine hemorrhage is not well understood. Here, we present and discuss the video-oculography findings of a patient with acute pontine hemorrhage who developed vertical pendular oscillation and ocular bobbing while comatose. The amplitudes, peak velocities, frequency distribution, and phase planes (velocity versus position) of the eye movements were analyzed. The vertical pendular oscillation was rhythmic with a peak frequency of 1.7 Hz, but amplitudes (mean 1.9°, range 0.2-8.2°) and peak velocities (mean 20.6°/s; range 5.9-60.6°/sec) fluctuated. Overall, their peak velocities were asymmetric, faster with downward than upward. Higher peak velocities were seen with larger amplitudes (downward phase r = 0.95, p < 0.001; upward phase r = 0.91, p < 0.001) and with movements beginning at eye positions lower in the orbit (downward phase r = - 0.64, p < 0.001; upward phase r = - 0.86, p < 0.001). Interspersed were typical ocular bobbing waveforms with a fast (peak velocity 128.8°/s), large-amplitude (17.5°) downward movement, sometimes followed by a flat interphase interval (0.5 s) when the eye was nearly stationary, and then a slow return to mid-position with a decaying velocity waveform. To account for the presence and co-existence of pendular oscillations and bobbing, we present and discuss three hypothetical models, not necessarily mutually exclusive: (1) oscillations originating in the inferior olives due to disruption of the central tegmental tract(s); (2) unstable neural integrator function due to pontine cell group damage involving neurons involved in gaze-holding; (3) low-frequency saccadic intrusions following omnipause neuron damage.

A Case of Auditory Neuropathy Caused by Pontine Hemorrhage in an Adult

A pontine hemorrhage can evoke several neurological symptoms because the pons contains various nuclei and nerve fibers. Hearing loss can develop as a result of a pontine hemorrhage because there is an auditory conduction pathway in the cochlear nucleus of the pons. However, very few cases of hearing loss caused by pontine lesions have been reported, and there have been no reports of auditory neuropathy that developed following a pontine hemorrhage. Recently we had a patient who experienced a nontraumatic pontine hemorrhage who was diagnosed with auditory neuropathy. The 34-year-old male patient was admitted to the emergency department with sudden alteration of mental status. His brain computed tomographic imaging revealed a hemorrhage in the central pons. He complained of hearing difficulties after his mental status recovered through conservative treatment, but a pure-tone audiogram showed very mild hearing loss in both ears. Further hearing tests using otoacoustic emissions, which showed normal responses, and auditory brainstem responses, which showed no waveforms at maximum stimulus intensity, revealed that his hearing difficulties were caused by auditory neuropathy. This case implies that the threshold of sound detection can be preserved in patients with pontine hemorrhage who complain of hearing difficulties. Auditory neuropathy should be considered as a possible cause of hearing difficulties in these patients and appropriate hearing tests should be performed.

Dural arteriovenous fistula manifesting as pontine hemorrhage at the craniocervical junction

Craniocervical junction (CCJ) dural arteriovenous fistula (DAVF) manifesting as intracerebral hemorrhage is extremely rare. We report the first case of CCJ-DAVF manifesting as pontine hemorrhage. A 69-year-old male presented with a pontine hemorrhage manifesting as a sudden onset of right hemiparesis and dysarthria. Digital subtraction angiography revealed a CCJ-DAVF fed by the meningeal branches of the right vertebral artery. The patient underwent surgical ligation of the cerebral draining veins to prevent re-bleeding. The postoperative course was uneventful. The patient had no neurological deficit after 1 month rehabilitation.

Dural Arteriovenous Fistula of the Sinus of the Lesser Sphenoid Wing Presenting with Pontine Hemorrhage

BACKGROUND

Dural arteriovenous fistulas (DAVFs) of the sinus of the lesser sphenoid wing (SLSW) with leptomeningeal drainage are rare. We report a patient with a DAVF of the SLSW draining into the basal vein of Rosenthal (BVR) presenting with pontine hemorrhage.

CASE DESCRIPTION

A 71-year-old man presented with sudden right hemisensory disturbance of the arm and leg. Brain computed tomography scan showed left pontine hemorrhage, and cerebral angiography revealed a DAVF of the left SLSW. The fistula drained solely into the left BVR, which had an anastomosis to the left lateral mesencephalic vein, which had a varix invaginated into the left pons. The diagnosis was a DAVF of the left SLSW drained into the lateral mesencephalic vein via the bridging vein of the left SLSW, the deep middle cerebral vein, and the BVR, and a varix of the lateral mesencephalic vein caused pontine hemorrhage. The fistula was occluded by clipping through frontotemporal craniotomy. The postoperative course was uneventful, and postoperative cerebral angiography confirmed disappearance of the fistula.

CONCLUSIONS

A DAVF of the SLSW presenting with pontine hemorrhage is extremely rare, and DAVFs with deep leptomeningeal drainage should be included among a variety of etiologies of pontine hemorrhage.

Rehabilitation for a Patient with Hemiplegia, Ataxia, and Cognitive Dysfunction Caused by Pontine Hemorrhage

Patients with pontine hemorrhage usually experience severe disturbances of consciousness, pupillary abnormalities, quadriparesis, and respiratory failure. However, little is known regarding cognitive dysfunction in patients with pontine hemorrhage. We report the case of a rehabilitation patient presenting with hemiplegia, ataxia, and cognitive dysfunction caused by a pontine hemorrhage. A 55-year-old, right-handed male suffered sudden onset of vertigo, dysarthria, and hemiplegia on the right side. He was diagnosed with brain stem hemorrhage, and conservative treatment was administered. The vertigo improved, but dysarthria, ataxia, hemiplegia, and gait disorder persisted. He was disoriented with respect to time and place and showed a poor attention span, impaired executive function, and reduced volition. A computed tomography revealed hematomas across the pons on both sides, but no lesions were obvious in the cerebellum and cerebrum. Single-photon emission tomography showed decreased perfusion in the brain stem, bilateral basal ganglia, and frontal and parietal lobes in the left hemisphere. The patient received exercise therapy and cognitive rehabilitation, and home modifications were performed to allow him to continue living at home under the supervision of his family. His symptoms improved, along with enhanced regional cerebral blood flow to the frontal and temporal lobes. These findings suggest that the pontine hemorrhage caused diaschisis resulting in secondary reduction of activity in the cerebral hemisphere and the occurrence of cortical symptoms. Therefore, rehabilitation is necessary, along with active instructions for the family members of patients with severe neurological deficits.

Usefulness of the combined motor evoked and somatosensory evoked potentials for the predictive index of functional recovery after primary pontine hemorrhage

Objective

To investigate the predictive index of functional recovery after primary pontine hemorrhage (PPH) using the combined motor evoked potential (MEP) and somatosensory evoked potential (SEP) in comparison to the hematoma volume and transverse diameter measured with computerized tomography.

Methods

Patients (n=14) with PPH were divided into good- and poor-outcome groups according to the modified Rankin Score (mRS). We evaluated clinical manifestations, radiological characteristics, and the combined MEP and SEP responses. The summed MEP and SEP (EP sum) was compared to the hematoma volume and transverse diameter predictive index of global disability, gait ability, and trunk stability in sitting posture.

Results

All measures of functional status and radiological parameters of the good-outcome group were significantly better than those of the poor-outcome group. The EP sum showed the highest value for the mRS and functional ambulatory category, and transverse diameter showed the highest value for "sitting-unsupported" of Berg Balance Scale.

Conclusion

The combined MEP and SEP is a reliable and useful tool for functional recovery after PPH.

Hypertensive brain stem encephalopathy with pontine hemorrhage: A case report

Hypertensive brain stem encephalopathy (HBE) is a rare, under diagnosed subtype of hypertensive encephalopathy (HE) which is usually reversible, but with a potentially fatal outcome if hypertension is not managed promptly. To the best of our knowledge, only one case of HE with brain stem hemorrhage has been reported. We report a case of HBE with pontine hemorrhage in a 36-year-old male patient. The patient developed severe arterial hypertension associated with initial computed tomography showing the left basilar part of pons hemorrhage, fluid-attenuated inversion-recovery showing hyperintense signals in the pons and bilateral periventricular, anterior part of bilateral centrum ovale. The characteristic clinical findings were walking difficulty, right leg weakness, and mild headache with nausea which corresponded to the lesions of MR imagings. The lesions improved gradually with improvements in hypertension, which suggested that edema could be the principal cause of the unusual hyperintensity on magnetic resonance images.