Innervation of the sternocleidomastoid and trapezius muscles by the accessory nucleus.

Images moving over the retina at velocities as low as a few degrees per second, in movements as head turning, can degrade visual acuity. Visual acuity requires that even minute motion of the head be compensated for, primarily via optokinetic and vestibular reflexes. Whereas we have a good understanding of some the neuronal networks involved in these reflexes, other components of this network, such as the innervation of the paired muscles that turn and tilt the head, are not as well understood. The involvement of the sternomastoid, cleidomastoid, or trapezius muscles with lesions of the cervicomedullary junction is often not in conformity with the prevailing neuroanatomic descriptions of their innervation by the accessory nuclei. We discuss evidence that: 1) the XI nucleus has a rostral and a caudal portion; 2) analogous to the VII nerve, the rostral portion receives projections from both cerebral hemispheres, whereas the caudal portion is innervated preferentially by the contralateral hemisphere; 3) the caudal XI nucleus innervates the ipsilateral cleidomastoid and trapezius with a predominantly crossed corticonuclear innervation; and 4) The rostral XI nucleus innervates both sternomastoids. Each rostral portion receives projections from both cerebral hemispheres. These anatomic features explain the seemingly discrepant findings in patients with cervicomedullary lesions.

Seizures, lateral decubitus, aspiration, and shoulder dislocation: Time to change the guidelines?

The recommendation to position a patient having a seizure on a lateral decubitus is aimed at minimizing the risk of aspiration. The authors reviewed the database of the Epilepsy Foundation Clinic of South Florida for patients with epilepsy treated for pneumonia between May 1999 and May 2000 and patients admitted to two university telemetry units who had dislocation of the shoulder during an epileptic seizure. Over 2 months, 2 of 733 adults with intractable seizures had aspiration pneumonia after a generalized tonic clonic seizure (GTCS). Although no study has specifically addressed the problem of aspiration pneumonia in adults with GTCS, our findings suggest this problem is not common. From the two epilepsy centers, 5 of 806 patients dislocated a shoulder during a seizure. Video recordings showed that these patients were positioned in a lateral decubitus by staff while still having the convulsion. The dislocated shoulder in all cases was on the lower side. The risk of shoulder dislocation in a convulsing patient positioned in a lateral decubitus is less than 1%. Nevertheless, dislocations can result in disabling recurrences and are easily preventable. Because aspiration is more likely in the postictal rather than ictal phase of a GTCS, when oral secretions are not usually increased and there is cessation of respiratory movements, lateral decubitus should only be implemented after cessation of the convulsion, In inpatients (such as those on telemetry), secretions may be better managed by bedside aspiration of the oral cavity.

Increased seizures after discontinuing carbamazepine: results from the gabapentin monotherapy trial.

Studies in patients with epilepsy undergoing telemetry evaluation for surgery have suggested that discontinuation of carbamazepine (CBZ) is associated with increased seizures. The period of observation in that setting, however, was limited to a few days. The authors reviewed the occurrence of seizures in patients with epilepsy who had all their antiepileptic medications discontinued during an 8-week period, converted to gabapentin monotherapy, and observed for 26 weeks as part of the gabapentin trial #945-082. Two hundred and seventy-five patients were enrolled. Kaplan-Meier estimates of time to exit for all patients showed that 18% of patients previously treated with CBZ completed the study as compared with 30% of the patients receiving other antiepileptic medications. Increase in the frequency of seizures was maximal in the 2 weeks following CBZ discontinuation. Seizures increased both in frequency and severity but no new seizure types were observed. The findings in this study show that removal of CBZ is associated with increased frequency of seizures in patients with a previous history of epilepsy with incompletely controlled seizures. The period of maximal increase was the first 2 weeks after CBZ discontinuation.

Persisting aphasia as the sole manifestation of partial status epilepticus.

OBJECTIVES: Persisting aphasia presenting as an isolated inability to vocalize is an uncommon presentation of simple partial status epilepticus and only eight such cases have been reported over the past 40 years. METHODS: We studied a patient with a 5-year history of recurrent episodes of inability to talk, without any other motor or cognitive impairments. Episodes lasted as long as 24 h, interictal EEGs were normal and she was diagnosed as a conversion disorder. RESULTS: EEG recordings during one of the episodes showed continuous discharges in the right frontal and parasagital areas demonstrating the ictal nature of the deficits. During the episode the patient had no deficits of strength, or in her ability to perform skilled movements to command, imitation or manipulation of objects. Comprehension of complex verbal commands was preserved and she would make attempts to articulate words and correctly answered questions with head nodding or monosyllables, yes or no. She could hum but had no other vocalizations. CONCLUSIONS: This is the first case of aphasic status epilepticus secondary to epileptogenic discharges of the right hemisphere. The case is also unique for the isolated involvement of production of language during the seizure.

Nonepileptic seizures in pregnancy.

The authors report five patients with recurrent psychogenic seizures (PS) during pregnancy, with multiple emergency room visits and continued intake of antiepileptic drugs obtained from various sources, despite awareness of the psychogenic nature of their attacks and the risks of antiepileptic drug use in pregnancy. These patients demonstrate that preexisting PS may persist during pregnancy, and there will be patients who continue to take antiepileptic drugs despite awareness of the risks inherent to these treatments. New-onset or persisting PS with pregnancy can be indicative of serious emotional conflicts, and the child should be considered at risk.

Fosphenytoin and phenytoin in patients with status epilepticus: improved tolerability versus increased costs.

Tonic-clonic status epilepticus (TCSE) is the most common neurological emergency and affects approximately 60000 patients each year in the US. The risk of complications increases substantially as TCSE lasts longer than 60 minutes. Ideally, drugs used to treat this condition should be well tolerated when administered as rapid intravenous infusions and should not interfere with patients' state of consciousness or cardiovascular and respiratory functions. Because of its efficacy, absence of sedation or respiratory suppression, intravenous phenytoin has largely replaced phenobarbital (phenobarbitone) as the second agent of choice (following the administration of a benzodiazepine) in the treatment of TCSE. While the efficacy of phenytoin in the treatment of acute seizures and TCSE is well established, the parenteral formulation of phenytoin has several inherent shortcomings which compromise its tolerability and limit the rate of administration. Intravenous phenytoin has been associated with fatal haemodynamic complications and serious reactions at the injection site including skin necrosis and amputation of extremities. Fosphenytoin, a phenytoin prodrug, has the same pharmacological properties as phenytoin but none of the injection site and cardiac rhythm complications of intravenous infusions of phenytoin. While fosphenytoin costs more than intravenous phenytoin, treating the acute and chronic complications of TCSE itself, and the complications of intravenous phenytoin can also be costly. All other factors being equal, there is no doubt that fosphenytoin is better tolerated and can be delivered faster than intravenous phenytoin; 2 measures that clearly improve outcome in patients with TCSE. The tolerability of intramuscular fosphenytoin also extends its use to clinical situations where prompt administration of a nondepressing anticonvulsant is indicated but secure intravenous access and cardiac monitoring are not available, such as treatment of seizures by rescue squads in the field and serial seizures in the institutionalised, elderly and other patients with intractable epilepsy.

Lidocaine and seizures.

Lidocaine has a concentration-dependent effect on seizures. At lower concentrations it has anticonvulsant properties, whereas concentrations above 15 microg/mL frequently result in seizures in laboratory animals and man. Seizures induced by lidocaine in experimental conditions invariably start in the amygdala. Despite the clear focal onset in these experimental models, the seizures emerging in patients given intravenous (i.v.) lidocaine are almost invariably generalized and without any clear signs of focality. Given the prevalence of partial seizures and the frequent use of lidocaine, a higher incidence of partial seizures would be expected with its use. Yet this is clearly not the case. These facts suggest that a history of partial seizures is not a major risk factor for the precipitation of partial seizures in patients treated with intravenous lidocaine.

Changing presentation of seizures with aging: clinical and etiological factors.

BACKGROUND: The historically higher incidence of seizures in children has changed, the elderly now have a higher incidence than any age-group, 2-3 times of that found in children. Classical teachings on etiologies, clinical presentation and progression of seizures are based on observations of a younger population and need to be revised in view of features unique to this age-group. The findings of two large VA cooperative studies show that even in sophisticated medical environments, up to 30% of patients 60 years and older with recurrent partial seizures go undiagnosed for more than 1 year of seizure onset. OBJECTIVE: (a) To characterize the manifestations of auras, seizures and postictal states in the elderly and the relevance of various etiologies to these presentations. (b) To identify and discuss factors that contribute to the difficulties in the diagnosis of seizures in this population. METHODS: A review of our experience in treating a large population of elderly patients in a university epilepsy center and a review of the literature relating to the problem. CONCLUSIONS: Seizures in the elderly are both overdiagnosed and underdiagnosed: either situation can have serious adverse consequences. Diversity of etiologies and atypical presentations make recognition of seizures difficult. Histories are frequently inadequate: complaints of multiple physical symptoms confuse the picture, unwillingness of elderly patients to admit to problems they believe are physiological in nature by the fear others may think they are 'losing their mind' and high staff turnover result in erratic identification of problems. The significant morbidity and mortality associated with poorly controlled seizures in this population are in large part preventable since excellent response to treatment can be achieved in more than 80% of individuals. The correct diagnosis of seizures is more likely if both physician and patients are familiar with the nuances of epilepsy in the elderly.

Restraining patients and shoulder dislocations during seizures.

We describe 3 patients whose shoulders dislocated as the movements of the arm were restricted during a generalized tonic clonic seizure over an 18-month period. The first patient had both shoulders dislocated when observers sat on his arms during the convulsion. The second patient had a convulsion while in a forced lateral decubitus position and dislocated the shoulder on that side. The third patient dislocated the shoulder and fractured the acromion as she was held by her arms in a chair during a convulsion. Despite the large number of patients with refractory epilepsy under our care, no cases of spontaneous shoulder dislocation occurred during that period of time.

Convulsive syncope following placement of sphenoidal electrodes.

Two cases of convulsive syncope following the insertion of sphenoidal electrodes are reported. The episodes occurred shortly after an uneventful insertion of the needle. Both patients exhibited behavioral arrest with loss of muscle tone, followed by flexor posturing, jerking of the extremities, then followed by what appeared to be a panic attack. Episodes were clinically distinct from the patients' typical spells and were initially interpreted as representing psychogenic events. EEGs during the episodes showed diffuse slowing followed by generalized suppression of rhythms. Simultaneous EKG showed bradycardia followed by brief asystole and then resumption of normal heart rhythms in both cases. Vagally mediated cardioinhibitory reactions induced by fear, pain and possibly stimulation of branches of the trigeminal nerve in the face represent an uncommon but potentially serious complication of placement of sphenoidal electrodes.

Skin eruption with gabapentin in a patient with repeated AED-induced Stevens-Johnson's syndrome.

Skin eruptions have been reported with the use of all antiepileptic drugs and there is a significant risk of cross-reactivity between these agents in causing serious eruptions such as Stevens-Johnson's syndrome. Gabepentin is usually considered a safe agent for patients with a previous history of drug allergies and there have been no cases of skin eruption reported to the gabapentin post marketing surveillance. We report a patient who had severe Stevens-Johnson's syndrome induced by phenytoin and later by carbamazepine. Subsequent use of gabapentin also resulted in a skin eruption which was limited to the lower extremities but without systemic or mucosal involvement. This case suggests that patients with a strong history of drug-induced idiosyncratic reactions may experience such reactions to gabapentin as well.

Progressive scoliosis in early, non-progressive CNS injuries: role of axial muscles.

Forty-three patients with progressive neurological deficits involving axial musculature, starting 3-6 years after non-progressive brain injuries insults are described. Losses of function followed period of several years of stable motor deficits. Subsequent losses were stereotypic, with loss of ambulation and scoliosis, followed by loss of word articulation, malalignment of the mandible and ultimately neurogenic impairment of swallowing. Physical therapy, serial castings and spinal instrumentation palliated specific musculoskeletal problems but did not alter the relentless loss of various functions. The balanced action of paired axial muscles (i.e. spine, proximal muscle groups of the lower extremities, oropharynx, mastication) is regulated by the brainstem with modulation by the cerebral hemispheres. The clinical evolution in these patients suggest that, in the absence of normal input from the cerebral hemispheres, some patients have a progressive loss of these brainstem mechanisms. The most resistant functions (last ones to be lost), seem to be the ones phylogenetically most relevant for survival, such as suction and swallowing.

Sternomastoid function during hemispheric suppression by amytal: insights into the inputs to the spinal accessory nerve nucleus.

The debate as to whether the sternomastoids receive ipsilateral, contralateral, or bilateral cortical innervation is based largely on the observation of stroke patients and, to a lesser extent, on animal experimentation. The variability of vascular lesions, the lack of pathology correlation in the early reports, and the differences in posture between humans and laboratory animals contributed to the controversy. We studied the function of the sternomastoid (SM) muscles during transient, complete left hemiplegia in 18 right-handed patients undergoing a Wada test. After injection in the right internal carotid artery (ICA), 14 patients were able to lift and turn their heads both to the right and to the left on command. Ten of the 14 patients who were able to follow commands after the injection had weakness of the right sternomastoid compared with the left. Our findings demonstrate that the left hemisphere can activate both the right and the left sternomastoid muscles during suppression of the right hemisphere. The sternomastoids receive bilateral hemispheric innervation and the maximal input comes from the ipsilateral hemisphere.

Seizures in the de-institutionalized patients with early brain injuries.

The number of individuals with early brain injury and multiple disabilities discharged from institutions had increased steadily over the past 10 years. The most frequently encountered problems by patients with early brain injury and epilepsy placed in the community were reviewed. Unavailability of specialized services, inadequate reimbursement, high turnover and lack of knowledge by caregivers, lack of understanding/acceptance of the concepts of seizure intractability and pseudoseizures, unrealistic expectations by overseeing agencies and/or family, and side effects of antiepileptic medications were the most common seizure-related problems afflicting these patients. Everything else being equal, good exchange of information between the various caregivers and continued education of caregivers, both time consuming endeavors, are the crucial factors for the successful management of seizures in this population.