Marco Giraudo

Occipital neuralgia as isolated symptom of an upper cervical cavernous angioma

Sirs: Occipital neuralgia (ON) (Arnold’s neuralgia) is characterized by jabbing pain attacks in the territory of occipital nerves associated to hypesthesia/dysesthesia in the same area [1, 2]. Pain frequently radiates to the frontal region and may be associated with tenderness over the affected nerve at the superior nucal line. ON can be caused by trauma, injury, inflammation, or compression of the greater occipital nerve somewhere along its course from the C2 dorsal root to the peripheral territory. A 59-year-old woman was referred to us in May 1999 because of a five-year history of pain involving the right occipito-parietal scalp, often radiating to frontal and retroauricular regions. The pain was sharp and burning with paroxysms triggered by pressure at the emergence of the greater occipital nerve and hyperalgesia for brush, touch and pinprick stimuli in the right occipital as well as in the auricular and retroauricular region. Skin rubbing at those levels caused paroxysmal attacks (for example when she held the telephone receiver over the right ear or put the right side of her head on a cushion). She complained of almost continuous uncomfortable paresthesias in the occipito-nucal area. Head and neck trauma were not reported. No clinical or laboratory evidence of rheumatologic disorders were present. Neurologic examination revealed only a slight hyperreflexia in the right limbs, without other signs of myelopathy. MRI showed a right intramedullary multilobated lesion at C1-C2 level (Figs. 1, 2) with a mild contrast enhancement. The lesion was slightly hyperdense on CT. Angiography of vertebral, common carotid and cervical branches from the subclavian arteries was normal . Therefore a diagnosis of intramedullary cavernous angioma was hypothesized. Amitryptiline and carbamazepine but not NSAIDs and greater occipital nerve anesthetic blockade were useful in reducing the pain. No change was evident on MRI performed 6 months later and the clinical picture was unchanged at the last visit in July 2001. The present case broadens the spectrum of causes of ON and suggests that spinal cord imaging may be useful also without clinical evidence of myelopathy. Indeed, in our patient ON was the unique symptom of an intramedullary cavernous angioma. About 5–10 % of central nervous system cavernous angiomas arise within the spinal cord and the cervical level is the most frequent after the thoracic [3]. They usually cause a progressive myelopathy through gradual enlargement and repeated microhemorrhages [3]. In ON pain and sensory symptoms involve the distribution of the branches derived from C2 spinal nerve. Just immediately after the origin the C2 spinal nerve gives rise to a ventral and a dorsal ramus. The greater occipital nerve raises from the dorsal ramus, enters the scalp through the trapezius aponeurosis at the superior nucal line and innervates the skin of the occipital area up to the coronal suture [1–5]. The lesser occipital nerve emerges from the C2 ventral ramus and supplies the scalp over the mastoid and the posterior surface of the ear. The C2 spinal nerve has several peculiarities [5]. It does not pass through an intervertebral foramen and therefore is relatively LETTER TO THE EDITORS

Restricted Dissociated Sensory Loss in a Patient With a Lateral Medullary Syndrome: A Clinical-MRI Study

Background Various sensory syndromes in lateral medullary infarctions are described. A small variation in the location of a lesion may lead to very different clinical features, owing to the complex anatomy of the medulla oblongata. MRI may identify the location and extent of the ischemic lesions, allowing a clear clinical-anatomical correlation. Case Description We describe a man with an ischemic lesion in the right portion of the lower medulla that presented a contralateral impairment of spinothalamic sensory modalities and an ipsilateral impairment of lemniscal modalities with a restricted distribution (left forearm and hand, right hand and fingers, respectively). The restricted and dissociated sensory abnormalities represent the only permanent neurological consequence of that lesion. Conclusions The atypical sensory syndrome may be explained by the involvement of the medial portion of spinothalamic tract and the lateral portion of archiform fibers at the level of the lemniscal decussation.

Palatal myoclonus in a patient with a lateral thalamic infarction

Palatal myoclonus (PM) is characterized by rhythmic involuntary jerking movement of the soft palate and the pharyngopalatine arch, often involving the diaphragm and laryngeal muscles.1 The two distinct clinical entities, symptomatic PM and essential PM, arise from different pathophysiologic mechanisms.2 Symptomatic PM is usually associated with lesions located in the myoclonic triangle (the Guillain–Mollaret triangle). It consists of the red nucleus, inferior olive, contralateral cerebellar dentate nucleus, and the connecting pathways, namely the central tegmental tract, the inferior cerebellar peduncle, and superior cerebellar peduncle.3 Symptomatic PM may be isolated or more rarely associated with movements of the extremities such as tremor, choreoathetosis, and myoclonus.4,5 A 64-year-old man was referred for acute onset of motor impairment of the right arm. On admission neurologic examination revealed clumsiness of the right arm and right dysmetria on finger-to-nose test. On the fifth day the patient developed myoclonic movements …

Internal carotid artery dissection after mandibular third molar extraction

Sirs: Cervicocephalic arterial dissection (CAD) is an important cause of cerebrovascular accidents in young and middle-aged patients [1]. CAD may be caused by major non-penetrating trauma of the cervical carotid and vertebral arteries; it more frequently occurs spontaneously or in association with trivial trauma causing hyperextension or rotation of the neck [1–4] . The activities include practicing yoga, sport activity, violent coughing and vomiting, sneezing, vigorous noseblowing, sexual activity, chiropractic manipulations, anaesthesia administration, car pushing, neck-turning while leading a parade, rhythmical flexion and extension of the neck to music, prolonged telephone usage with flexion in the neck and childbirth [1–4]. We describe a patient with a left parietal infarction caused by extracranial carotid artery dissection occurred after a removal of the left mandibular third molar. A 47-year-old woman had a sudden onset of a right visual field defect and slight sensorimotor impairment involving her right arm. For two weeks she had been affected by a periodontal infection, unsuccessfully treated with antibiotics. Six days before the stroke onset she underwent a difficult left lower third molar extraction. No direct trauma related to the dentist’s instruments was reported. After surgery the dental pain spread to the entire head on the left side. Neurological examination on admission revealed a right homonymous hemianopia and a mild sensory impairment in the right hand. Brain MRI revealed a parieto-occipital infarction in the territory of a parietal branch of the middle cerebral artery and an intramural haemorrhage in the intrapetrous portion of the left internal carotid artery (Fig. 1A). Duplex ultrasonography of the carotid arteries was normal. Conventional angiography revealed an irregular stenosis of the left internal carotid artery extending from the carotid bulb to the base of the skull (Fig. 1B); the contralateral carotid artery was normal, while both the vertebral arteries appeared tortuous. Conventional vascular risk factors as well as clinical conditions predisposing to arterial dissection were absent. In particular, features of type IV Ehlers-Danlos syndrome, Marfan’s syndrome, pseudoxanthoma elasticum, osteogenesis imperfecta type I and systemic lupus erythematosus were absent. A wide variety of physical stresses causing CAD has been described [1–4] but until now no case has been reported as a result of dental extraction. Hyperextension of the neck associated with sudden neck movement due to a difficult third molar extraction is the proposed mechanism causing the carotid dissection in our patient. Cervical extension and sudden neck movement may compress the cervical carotid artery against the transverse processes or the bony mass of the upper cervical vertebrae [4]. During dental extraction the opening of the mouth reduces the distance between mandibular angle and upper cervical vertebrae thus favouring the compression of the cervical carotid artery. The mechanical stretching of the soft neck tissue may cause the rupture of the intima and media tunica with LETTER TO THE EDITORS

Emotional facial paresis in a patient with a lateral medullary infarction.

Emotional facial paresis (EFP) is characterized by a weakness of inferior facial muscles evident during emotionally evoked movements but not during voluntary contraction. EFP is described in patients with lesions of the supplementary motor area, basal ganglia, temporal lobes, frontal white matter, anterolateral thalamus, anterior limb of the internal capsula, and brainstem tegmentum.1,2⇓ Voluntary facial paresis (VFP) is caused by lesions of the motor cortex or descending pyramidal tract at the level of the corona radiata, posterior limb of the internal capsula, ventral mesencephalon, and ventral pons.1 We describe a patient with EFP due to a small lesion in the upper medulla oblongata. A 60-year-old man presented with sudden onset of vertigo, dizziness, dysphagia, hoarseness, and facial paresis. He had hypercholesterolemia and a family history of stroke. Admission neurologic examination found mild gait ataxia, left Horner’s syndrome, hiccups, and hypesthesia for tactile and thermic sensation involving arm and trunk on …

Restricted pain and thermal sensory loss in a patient with pontine lacunar infarction : a clinical MRI study

Pure sensory syndrome (PSS) is characterized by hemisensory symptoms without other major neurological signs. It was initially attributed to thalamic lacunar infarction, but several reports have shown the PSS can be due to small infarcts involving the posterior part of the internal capsula, the cerebral cortex and the brainstem. Paramedian and lateral pontine infarctions are associated respectively with lemniscal and spinothalmic (ST) sensory impairment. We describe a patient with an isolated impairment of the ST modalities caused by a segmental paramedian pontine infarction.

Transient compulsive hyperphagia in a patient with a thalamic infarct.

Eating disorders are associated with various psychiatric and neurological diseases. Pathological eating behaviour ranges from reduced to excessive appetite, dysregulation of hunger and satiation signals, and odd food preferences. Hyperphagia and anorexia are reported in lesions (mostly tumours) involving the ventromedial hypothalamus.1 Moreover, eating disorders also occur in temporal lobe tumours, temporal lobe epilepsy, and advanced states of degenerative disease with neuronal loss in the medial temporal lobe. Hyperorality is part of the Kluver-Bucy syndrome which occurs in patients with bilateral mesial temporal lesions.1 We report a patient in whom compulsive hyperphagia was associated with a medial thalamic ischaemic stroke. A 52 year old man complained of diplopia, dizziness, vertigo, decrease of consciousness, memory impairment, and hyperphagia. These symptoms occurred abruptly while he was painting the gate in his garden. The diplopia and vertigo disappeared in about 15 minutes, while hyperphagia and memory impairment lasted for about 24 hours and completely disappeared the following day on awakening. Instead, amnesia concerning the event is still present. The decrease of consciousness consisted of slight hypersomnolence (the patient could easily be awakened by auditory and verbal stimulation) and was present only at the onset, while memory impairment was noted only later. The patient’s wife reported that he …

Asymptomatic white matter ischemic lesions in a patient with pseudoxanthoma elasticum

Sirs: Pseudoxanthoma elasticum (PXE) is an inherited connective tissue disorder, characterized by cutaneous, ophthalmological, cardiac and diffuse vascular abnormalities due to progressive calcification of abnormal elastic fibers in the dermis, in Bruch’s membrane in the eye and within the arterial wall [1]. The vascular complications may be due either to a primary cerebral vessel disorder or indirectly to the hypertension that frequently occurs in patients with PXE [1, 4]. We describe a patient with PXE in whom multiple silent white matter ischemic lesions occurred in the absence of hypertension. A 44-year-old woman complained of a progressive visual loss in her left eye. Ophthalmological examination and retinal angiography (Fig. 1A) disclosed chorioretinal scarring, macular degeneration in the left eye and angioid streaks in both eyes that were treated with laser photocoagulation. Brain MRI revealed multiple white matter abnormalities involving the cerebral hemispheres (Fig. 1B and C): the ischemic lesions were located at subcortical level and spared basal ganglia, brainstem and cerebellum. Admission neurological examination was normal. Multiple sclerosis and lacunar infarctions due to a small vessel disease were hypothesized. Conventional vascular risk factors such as hypertension, cigarette smoking, diabetes, hypercholesterolemia were absent. Routine blood tests including immunologic, coagulative parameter and homocisteinemia were normal. The cerebrospinal fluid examination was normal including oligoclonal bands. Somatosensory and brainstem auditory evoked potentials were normal while visual evoked potentials were modified only in the peripheral pattern. Electrocardiogram, transthoracic and transesophageal echocardiography were normal. Dermatological examination revealed the presence of 1–3 mm yellowish papules coalescing in a reticular and linear pattern, associated with teleangiectasia on a soft, lax and wrinkled skin, resembling “plucked chicken skin” (Fig. 1D). These lesions involved the neck and, to a lesser degree, the flexor surface of the elbow. The association of angioid streaks in the retina and typical skin lesion suggested the diagnosis of PXE. Histopathological examination of a biopsy sample from the skin of the neck showed irregular clumped fibers, degenerated elastic fibers associated with calcium deposits in the reticular dermis, confirming the clinical diagnosis of PXE (Fig. 1E and F). The haplotype and mutational analysis of the ABCC6 gene using DNA sample of the patient’s serum identified two different nucleotide substitutions: one at exon 24 (c.3421 C > T) and the other at exon 28 (c.3940 C > T). Antiplatelet drugs were avoided because of the increased risk of hemorrhagic complications. PXE is a rare disorder with a prevalence ranging from 1 in 100,000 to 160,000. The inheritance is usually autosomal recessive but may be autosomal dominant or sporadic [1]. Recently, the ATPbinding cassette subfamily C member 6 (ABCC6) gene, in the chromosome 16p13.1, has been demonstrated to be responsible for PXE [6]. The most typical clinical manifestations are cutaneous lesions occurring in the second or third decade of life, consisting of small yellowish papules coalescing into plaques with a plucked chicken skin or cobblestone appearance in flexural regions, most commonly over the neck and the axillae [1, 2]. The involved skin may result in redundant skin folds and the eruption may progress to involve most of the body surface. Ocular findings include angioid streaks in the retina, result of cracks or ruptures in Bruch’s membrane (which has been weakened by disruption of elastic fibers), retinal hemorrhage and detachment, chorioretinal scarring, pigmentary deposits and macular degeneration.A hemorrhagic diathesis, mainly in the gastrointestinal tract is not uncommon [1, 2].Abnormalities in the elastic tissue of the endocardium can produce thickened mitral valves, mitral annulus calcification, mitral stenosis, mitral valve prolapse, calcification of the endocardium and a restrictive cardiomyopathy [1]. Common vascular complications of PXE are premature arteriopathy with stenosis, aneurismal dilatation and calcification involving medium-sized peripheral arteries [1, 2]. Premature ischemic heart disease, intermittent claudication, abdominal angina and cerebrovascular disease are common features [1]. Cerebral ischemic events usually occur in the fifth or sixth decade. Moreover hypertension is LETTER TO THE EDITORS