Achim Druschky

Differentiation of Parkinson's disease and multiple system atrophy in early disease stages by means of I-123-MIBG-SPECT

BACKGROUND Differential diagnosis between idiopathic Parkinsons disease (PD) and multiple system atrophy (MSA) is often difficult in early disease stages. Since MSA is misdiagnosed as PD in more than 20% of the early stages, there is need for methods refining the differentiation of the two disease entities. In PD postganglionic involvement of the autonomic nervous system (ANS) predominates whereas in MSA the ANS is mainly affected in its preganglionic structures. The functional integrity of postganglionic cardiac sympathetic neurons can be investigated using I-123-metaiodobenzylguanidine-single photon emission computed tomography (MIBG-SPECT). OBJECTIVES We investigated whether I-123-MIBG-SPECT allows to differentiate between early stages of PD and MSA in patients not yet requiring L-dopa therapy. METHODS Thirty patients (10 PD and 20 MSA patients) underwent MIBG-SPECT and evaluation of heart rate variability (HRV). Patients on any medication interfering with MIBG-accumulation were excluded from the study. Cardiac perfusion was evaluated by myocardial scintigraphy. RESULTS The median cardiac MIBG uptake was significantly decreased in PD as well as MSA patients compared to controls (P<0.001). However, in the PD group MIBG uptake was significantly lower than in MSA (P=0.03). Even in PD patients without clinical signs of autonomic failure, MIBG uptake was significantly lower than in MSA patients (P=0.03). Analysis of heart rate parameters did not differentiate between PD and MSA patients. The median coefficient of variation was significantly smaller in PD and MSA patients compared to control subjects. CONCLUSIONS Our study shows that MIBG-SPECT identifies autonomic cardiac dysfunction in very early stages of both, PD and MSA. More importantly, the technique facilitates differentiation of MSA and PD in the early stages. The different pathology with prominent peripheral, postganglionic sympathetic dysfunction in PD and primarily central and preganglionic lesions in MSA accounts for a lower MIBG uptake in PD compared to MSA patients.

Herniated cervical intervertebral discs with radiculopathy : An outcome study of conservatively or surgically treated patients

To study the functional outcomes of patients with cervical herniated intervertebral discs with radiculopathy but without signs of cervical myelopathy using a retrospective cohort study design. The patients were retrospectively identified by chart reviews. Inclusion criteria were (a) cervical radiculopathy with defined neurological disturbances (sensory disorder, reflex abnormalities, and motor weakness); (b) a spinal computed tomograph scan or magnetic resonance image demonstrating neuroradiologic abnormalities (soft or hard disc); and (c) completion of conservative physical and pharmacological treatment. Of 119 consecutive patients who were treated at the Departments of Neurology and Neurosurgery, University of Erlangen-Nuremberg, between January 1, 1985, and December 31, 1995, 60 patients met the inclusion criteria and were prospectively assessed, with an average follow-up time of 5.5 years. The patients were interviewed with regard to their daily activities, ability to work, and the surgical treatment they had undergone. A complete neurological examination also was performed. In 88.3%, the onset of disease was acute and in 11.7% subacute or chronic. The most common signs and symptoms were brachialgia (98.3%), neck pain (93.3%), sensory disorders (88.3%), reflex abnormalities (61.7%), and motor weakness (51.7%). The neuroimaging procedures demonstrated a disc prolapse (soft disc) in approximately 90% and spondylotic osteophytes (hard disc) in approximately 10%. During an average follow-up time of 5.5 years (range, 4.6 months-10.6 years) 39 (65%) patients had been treated using only conservative methods (COG = conservatively treated group), and 21 (35%) patients had undergone surgery (ventral discectomy) (SUG = surgically treated group). Brachialgia was completely or essentially improved in 100% of the COG and 95.1% of the SUG. Sensory disorders remitted completely or markedly in 97% of the COG and 75% of the SUG. The reflex abnormalities normalized or improved in 59.2% of the COG and in 53.3% of the SUG. Motor weakness improved in 94.1% of the COG and in 50% of the SUG. Neck pain was difficult to treat. It improved in only 36.1% of the COG and in 20% of the SUG. Occupational capacity was lost in 10% of the COG and in 38.9% of the SUG. In a self-rating scale, 89.7% of patients in the COG did not feel disabled in their everyday activities, compared with 66.7% of the patients in the SUG. Patients with a herniated cervical intervertebral disc with radiculopathy can be treated conservatively with good results, although a residual intermittent neck pain syndrome often persists. The patients in the SUG, who initially showed more severe and long-lasting neurological disturbances, were improved at the time of examination, although with more marked residual disorders. Surgery is indicated only when appropriate conservative treatment for a reasonable time has failed.

Alteration of the somatosensory cortical map in peripheral mononeuropathy due to carpal tunnel syndrome.

Substantial plasticity of the mature mammalian somatosensory cortex was demonstrated after deprivation of sensory input produced by amputation or somatosensory deafferentation. Following transection of the median nerve, adult owl and squirrel monkeys exhibit extensive reorganization in the cortical representation of the hand in areas 3b and 1. In the present study we investigated the possible effect of incomplete median nerve damage on sensory cortex somatotopy in a patient with unilateral carpal tunnel syndrome. We assessed interhemispheric differences of the hand representation in SI by means of magnetic source imaging. Additional intersubject data comparison was performed for specific results on the basis of available normal data from the literature and from own investigations in five healthy volunteers. Our results demonstrated a decreased extension of the cortical zone representing the injured median nerve and suggested invasion of the deprived area by cortical sectors receiving inputs from the little finger (supplied by the ulnar nerve) and from the dorsum of the thumb (innervated by the radial nerve). The study indicates topographic rearrangement of the hand representational zone in the human primary somatosensory cortex in a case of chronic median nerve injury.

Outcome of epilepsy surgery correlates with sympathetic modulation and neuroimaging of the heart.

Temporal lobe epilepsy (TLE) is frequently associated with sympathetic over-activity. Single photon emission computed tomography (SPECT) with 123iodine-meta-iodobenzylguanidine (MIBG), a norepinephrine analogue, showed reduced tracer uptake in cardiac sympathetic nerve endings, indicating myocardial catecholamine disturbance. We investigated whether outcome of epilepsy surgery correlates with cardiac autonomic function in TLE patients. We studied 16 TLE patients before and after epilepsy surgery. We recorded heart rate (HR) and determined sympathetic and parasympathetic cardiac modulation as powers of low (LF, 0.04-0.15 Hz) and high frequency (HF, 0.15-0.5 Hz) heart rate oscillations. The LF/HF-ratio was calculated as index of sympathovagal balance. Cardiac MIBG uptake was assessed with MIBG-SPECT and compared to control data. After surgery, eight patients were seizure-free and eight had persistent seizures. Sympathetic LF-power and LF/HF-ratio were higher in patients who had persistent seizures than in patients who became seizure-free. After surgery, both parameters decreased in seizure-free patients but increased in patients with persistent seizures. MIBG uptake was lower in patients than controls and even lower in the patient subgroup who had persistent seizures. In this subgroup, MIBG uptake further decreased after surgery (P<0.05). Sympathetic cardiac modulation decreased in TLE patients after successful surgery, but further increased if seizures persisted. Reduction of cardiac MIBG uptake progressed after surgery in patients with persistent seizures. Interference of epileptogenic discharges with autonomic neuronal transmission might account for sympathetic cardiac over-stimulation and reduced MIBG uptake. Both findings are possible risk factors for sudden unexplained death and might be relevant for risk stratification in epilepsy patients.

Somatotopic Organization of the Ventral and Dorsal Finger Surface Representations in Human Primary Sensory Cortex Evaluated by Magnetoencephalography

Cortical reorganization of the subtly differentiated hand map after peripheral nerve injury might be better understood if there was a topographic conception of the homuncular representation of the dorsal finger surfaces in humans, in addition to the well-established sequential rostrocaudal array of the ventral finger aspects in cortical area 3b. In the present magnetoencephalographic study, tactile pneumatic stimulation was delivered to the fingertip and to the ventral and dorsal proximal phalanx of each digit of the dominant hand in 20 right-handed volunteers. Source localization of equivalent current dipoles underlying the recorded somatosensory evoked magnetic field was performed using a Cartesian coordinate system established by the anatomical landmarks nasion and preauricular points. Of the first major peak of each somatosensory evoked field, the region with the maximum field power (root-mean-square across channels) was selected for source reconstruction. Analysis of variance for repeated measures yielded significant results with respect to the arrangement of digits along the vertical coordinate axis, demonstrating a sequential array from the most inferiorly located D1 to the most superiorly located D5 for all different stimulus positions. This is the first study providing evidence for a sequential topographical arrangement of not only the ventral but also the dorsal surface representations of the individual digits in the human somatosensory cortex. The study contributes to a better understanding of the somatosensory hand representation in human primary cortex and provides useful information with regard to cortical plasticity studies in patients with peripheral nerve injuries at the upper extremity.

Disappearance of resting tremor after “stereotaxic” thalamic stroke

Both stereotaxic thalamotomy and deep brain stimulation have been shown to be effective treatment for drug-resistant resting tremor in selected patients.1 The preferred targets of surgical intervention are the thalamic nucleus ventralis intermedius (Vim) and an area a millimeter anterior to the nucleus ventrocaudalis (Vc), which have been associated with relief of tremor with contralateral paresthesia and hypesthesia the commonest side effects.2 We report a patient with Parkinson disease (PD) with disappearance of contralateral resting tremor after a pure sensory stroke involving the posterolateral part of the left thalamus. A 67-year-old man suddenly developed numbness in the right lower lip, the right part of the tongue, and the right hand. He had been followed by our department for PD for 7 years, and initially …

Severe neurological complications of ulcerative colitis

A 37 year old man presented with a 15 year history of ulcerative colitis. On examination he had weakness of the right arm, slurred speech and progressive confusion, followed by a rapid deterioration of consciousness and motor functions resulting in coma, tetraparesis and bilateral Babinski responses. Magnetic resonance imaging of the brain and spinal cord revealed multiple hyper- and hypointense white matter lesions. Clinical symptoms, history and neuroradiological findings led to the diagnosis of an ulcerative colitis-associated CNS disorder. An autoimmune vasculitic process may have played an important pathophysiological role, considering the vasculitic changes observed by skin biopsy as well as the rapid clinical improvement following immunosuppressive therapy with corticosteroids and azathioprine. During a follow up period of more than one year we observed continuous and complete recovery of neurologic symptoms.

An instructive false diagnosis: steroid-induced complete remission of a CNS tumor--probably lymphoma.

In recent years the incidence of primary cerebral lymphomas has increased. Diagnosis by imaging techniques (CCT, angiography MRT) and stereotactic biopsy are considered as reliable diagnostic tools. Therapeutically a combination of radio-, steroid- and chemotherapy is recommended. We report a case of space-occupying CNS lesion in which the radiopaque enhancing process completely disappeared after biopsy and steroid therapy. A year later the tumor recurred on the other side and again regressed after steroid therapy. The first biopsy showed signs of a papillar tumor, so a choroid plexus papilloma was suspected. On examination of the treatment history, however, this diagnosis had to be revised. A primary CNS lymphoma seems most probable. The phenomenon of a tumor remission under steroid administration and the problems related to the differential diagnosis are discussed.

Central Nervous System Involvement in Thrombotic Thrombocytopenic Purpura

Thrombotic thrombocytopenic purpura (TTP) is an uncommon multisystem disease characterized by microangiopathic hemolytic anemia, thrombocytopenic purpura, fluctuating neurologic dysfunctions, renal disease, and fever. Delayed diagnosis and treatment may lead to a high mortality rate that can be as great as 90%. We describe 7 patients in whom CNS involvement was the first clinical manifestation of TTP. Despite early diagnosis and treatment, 3 patients died because of multiple system organ failure. Four patients recovered completely. In patients with focal neurologic disorders in whom infectious CNS diseases were excluded TTP should be considered in the differential diagnosis.

Progression of optic neuritis to multiple sclerosis: an 8-year follow-up study

OBJECTIVE The relationship between acute monosymptomatic optic neuritis (AON) and subsequent multiple sclerosis (MS) is still doubtful. We investigated the risk of developing MS in patients from North Bavaria, who were suffering from AON. PATIENTS/METHODS Twenty-nine patients with clinical evidence of AON were included in the study. Initial evaluation included brain resonance imaging (MRI) and a clinical neurological examination. Follow-up examinations were performed after 72-108 months (mean: 96 months) in 26 patients (three patients were lost to follow-up) and consisted of a second complete neurological examination. Diagnosis of MS was established according to the criteria of Poser CM, Paty DW, Scheinberg L. New diagnostic criteria for multiple sclerosis: guidelines for research protocols. Ann Neurol 1983:13:227-231. RESULTS At follow-up, 14 of 26 patients (54%) had converted to clinically definite MS. Nine patients (64%) had developed MS within 2 years after the onset of AON. CONCLUSION We observed the development of MS in 54% of the 26 investigated AON patients. The exceptional feature of the present study was the relatively long follow-up period of 8 years.