Secondary amyloidosis as a life-ending event in multifocal motor neuropathy

Multifocal motor neuropathy (MMN) is a disorder of peripheral nerve often associated with a high monosialoganglioside (GM1) antibody and multifocal conduction block. It has a chronic, indolent course with involvement of predominantly peripheral motor nerves, usually in an asymmetric fashion. There have been few reported cases of progression to frank quadriplegia. Secondary amyloidosis refers to the deposition of amyloid in various tissues due to an underlying chronic inflammatory state. We report the first case, to our knowledge, of a patient with MMN associated with high titer of GM1 antibody who developed acute paraplegia with both cranial nerve and worsening sensory involvement associated with multiorgan compromise due to a secondary amyloidosis involving the myocardium.

Drop metastasis from sinonasal undifferentiated carcinoma: clinical implications

STUDY DESIGN

The first reported case of multiple intradural, extramedullary spinal metastasis from sinonasal undifferentiated carcinoma is presented.

OBJECTIVES

To elucidate the mechanisms by which metastatic disease invades the spinal axis, and to discuss the possibility of spinal drop metastasis from head and neck tumors that invade the dura.

SUMMARY OF BACKGROUND DATA

Sinonasal undifferentiated carcinoma is a rare yet aggressive neoplasm of the upper airways and anterior skull base. This neoplasm is known to invade the cranial vault and brain locally. However, it has not previously been reported to seed the cerebrospinal fluid or result in drop metastasis. Such drop metastasis may result in significant neurologic deficit if not diagnosed and treated in a timely manner.

METHODS

This report is based on a single patient treated by a multidisciplinary team from the departments of neurosurgery, otolaryngology, and radiation oncology at the University of Southern California School of Medicine.

RESULTS

This patient initially underwent resection and local radiation therapy for sinonasal undifferentiated carcinoma of the anterior skull base. At the time of surgery, the tumor was noted to violate the dura and arachnoid along the subfrontal plane. At 11/2 years after the initial treatment, a bandlike distribution developed at T2 as well as paresthesias and numbness below that level. Imaging of the spine showed an intradural, extramedullary tumor at T2 consistent with a schwannoma or meningioma. The patient underwent a laminectomy and tumor resection, which showed poorly differentiated sinonasal carcinoma. Local radiation therapy was administered, and the patient experienced complete recovery of neurologic function. Bilateral leg pain and weakness developed 14 months later. Magnetic resonance imaging of the spine showed a new intradural, extramedullary lesion at T12, remote from the first lesion. This second metastasis was managed with surgical resection and adjuvant radiation therapy.

CONCLUSIONS

This is the first reported case of a sinonasal carcinoma leading to intradural extramedullary metastasis. The primary tumor likely seeded the cerebrospinal fluid, thus resulting in drop metastasis. Patients with sinonasal undifferentiated carcinoma that invades the dura should be monitored closely for evidence of metastasis before symptoms develop.

A study of vestibular schwannomas using positron emission tomography and monoclonal antibody Ki-67

OBJECTIVE

This study aimed to evaluate the role of positron emission tomography (PET) as an in vivo determinant of tumor aggressiveness and growth.

STUDY DESIGN

The study design was a prospective pilot study.

SETTING

Positron emission tomography was performed at the Clarke Institute of Psychiatry. All patients were treated at the Sunnybrook Health Science Centre. Both institutions are affiliated with the University of Toronto, Toronto, Canada.

PATIENTS

The study consisted of five consecutive patients with vestibular schwannomas with tumor size of 1 cm or larger within the cerebellopontine angle. One was a recurrent tumor and four were primary tumors.

INTERVENTIONS

Preoperative PET studies were conducted using 18-fluorodeoxyglucose (FDG) as a radionuclide tracer to measure glucose metabolism within tumors. Tumors were processed and immunostained against Ki-67 nuclear antigen; their proliferative potentials were quantified based on immunoreactivity of tumor cells.

MAIN OUTCOME MEASURES

Tumor metabolic activity on PET was compared with that of contralateral cerebellum to arrive at an FDG index. This number was compared with clinical parameters and Ki-67 reactivity.

RESULTS

On PET, all tumors showed less metabolic activity than the cerebellum. The FDG uptake varied greatly between tumors independent of clinical parameters. All the tumors had a low proliferative index (<5%) with immunohistochemistry; there were quite a bit of intralesional variations in proliferative activities.

CONCLUSION

Large tumor size and recurrent disease did not correlate well with increased FDG uptake on PET. Similarly, they did not show increased cellular activities as expressed by Ki-67 immunostaining.

The role of endoscopic stapling diverticulotomy in recurrent pharyngeal pouch

Endoscopic stapling diverticulotomy is an increasingly popular treatment option for pharyngeal pouch. It has been our treatment of choice for the condition for over three years. Of the over 50 cases treated using the technique, three were performed for recurrent pouches--two following previous endoscopic stapling diverticulotomy and one following previous external excision. We describe these three cases to highlight the advantages and effectiveness of the technique in recurrence cases.

Sjogren's cerebritis complicated by subarachnoid hemorrhage and bilateral superior cerebellar artery occlusion: case report

We report a case of chronic Sjogren's cerebritis complicated by bilateral superior cerebellar artery occlusion and diffuse subarachnoid hemorrhage. Although primary Sjogren's syndrome with chronic leptomeningeal involvement has been well documented and a spectrum of central nervous system disease previously outlined, no case of intracranial subarachnoid hemorrhage with major intracranial vessel occlusion has been reported.

Hypothalamic chordoma. Case report

The case is reported of a 51-year-old woman found to have a hypothalamic mass with the histological features typical of chordoma. This represents the first description of a chordoma arising within the brain.

The management of neonatal rhinitis

Life-threatening upper airway obstruction secondary to neonatal rhinitis is a rare and poorly understood condition. Despite potential lethal effects, there has been no basic scientific research investigating the nature of this curious condition. This paper retrospectively reviews 8 patients suffering from neonatal rhinitis. Both the medical and surgical management of neonatal rhinitis and possible aetiological factors involved are discussed. Increasing clinical awareness of this condition may, therefore, serve as inspiration for future research of both an epidemiological and basic scientific nature.

Atropine infusions near the sexually dimorphic area of the gerbil hypothalamus facilitate hormonal induction of scent marking

The sexually dimorphic area (SDA) of the gerbil hypothalamus contains cells in which acetylcholinesterase activity is stimulated by testosterone. These cells are probably cholinoceptive. Because cholinoceptive cells and the SDA are both implicated in hormonal control of gerbil scent marking, marking was studied in castrated males given a low dose of testosterone systemically, and atropine, a cholinergic antagonist, near the SDA. Controls received saline near the SDA or atropine in the thalamus. Subjects were also tested for male sexual behavior, since it is also affected by the SDA. Infusing 25-35 micrograms atropine methyl nitrate near the SDA twice a week facilitated marking but did not affect mating. Experimental males marked more, whereas controls marked less, while receiving infusions, than they did before castration. The two control groups did not differ from each other. After infusions stopped, marking by experimental males decreased, though residual effects were detected in one test setting. The data suggest that a cholinoceptive system in or near the SDA participates in hormonal control of gerbil scent marking.

Autoradiographic localization of estrogen and androgen receptors in the sexually dimorphic area and other regions of the gerbil brain

Autoradiography was used to localize sex hormone-accumulating cells in the gerbil brain. Some areas had a high density of both androgen and estrogen receptors. These areas included the lateral septum, the bed nucleus of the stria terminalis, the medial and cortical amygdaloid nuclei, the medial preoptic area (MPOA), the arcuate nucleus, the ventromedial hypothalamus, and the periventricular central gray. This distribution of hormone receptors agrees closely with that seen in other mammals. In contrast to what has been reported for other species, the distribution of estradiol-accumulating cells in the gerbil MPOA is different in males and females. Estradiol uptake in the posterior MPOA followed the morphology of a sexually dimorphic area (SDA) and was therefore sexually dimorphic. Moreover, the percentage of SDA cells that accumulated estradiol appeared to be higher in males than in females. The pattern of androgen accumulation also followed the morphology of the SDA but differed from the pattern of estrogen accumulation in one way. The uptake of 5 alpha-dihydrotestosterone in the SDA pars compacta (pc), a component of the SDA, was much greater than in the rest of the SDA. This was not true for estradiol. Since most females lack the SDApc, androgen uptake in the gerbil SDA may also be sexually dimorphic. Androgen uptake was more widespread than estrogen uptake in the brainstem. Brainstem nuclei that accumulated 5 alpha-dihydrotestosterone included the locus ceruleus, the dorsal raphe, the hypoglossal nucleus, the area postrema, the nucleus of the solitary tract, and the dorsal nucleus of the vagus.

Lesions of the sexually dimorphic area disrupt mating and marking in male gerbils

At the border between the medial preoptic area (MPOA) and the anterior hypothalamus (AH), gerbils have a sexually dimorphic area (SDA) that accumulates and responds to gonadal steroids. To assess the role of the SDA in the hormonal control of two sexually dimorphic behaviors, masculine sexual behavior and ventral scent marking, we studied changes in these behaviors in male gerbils after lesioning the lateral SDA or the entire SDA. Lateral SDA lesions disrupt openfield scent marking, at least temporarily, and produce long-lasting deficits in, but do not abolish, mating behavior. Lesioning both the medial and the lateral SDA produces more profound deficits in mating and marking. Similar lesions anterior or posterior to the SDA also impair these behaviors, but their effects are less severe. Thus the SDA is more important than other parts of the MPOA-AH in the control of mating and marking in male gerbils.

Adult testosterone levels influence the morphology of a sexually dimorphic area in the Mongolian gerbil brain

This research shows that the medial preoptic area-anterior hypothalamus (MPOA-AH) of the gerbil contains a sexually dimorphic area (SDA) whose morphology is influenced by adult gonadal steroids. The characteristics of the SDA were studied initially in gonadally intact males and females and later in males and females that had been gonadectomized or gonadectomized and given testosterone. Coronal sections through the MPOA-AH were stained with thionin to visualize the SDA. In male gerbils, the SDA is a darkly staining, hook-shaped structure on either side of the third ventricle, above the suprachiasmatic nuclei and below the anterior commissure. Within the male SDA lies a small, dense cluster of cells, the SDA pars compacta (SDApc). In female gerbils, the SDA is more ovoid and diffuse and the SDApc is absent. Camera lucida tracings and planimeter measurements of the SDA showed that the total volume of the SDA is similar in the two sexes, but the proportion of the SDA that stains darkly and/or stands out clearly from the surround (dark volume) is larger in males. Gonadectomy decreases both total and dark volume of the SDA in both sexes and decreases the volume of the SDApc in males. Testosterone treatment prevents these changes. This is the first report of changes in the gross morphology of the mammalian brain after steroid hormone manipulations in adulthood. The changes in the SDA may be related to testosterone activation of scent marking behavior.

Acetylcholinesterase activity in the sexually dimorphic area of the gerbil brain: sex differences and influences of adult gonadal steroids

The morphology of the medial preoptic area-anterior hypothalamus (MPOA-AH) of gerbils is sexually dimorphic and influenced by adult gonadal hormones. This research shows that the distribution of (MPOA-AH) cells that synthesize acetylcholinesterase (AChE) and the activity of AChE within the MPOA-AH are also sexually dimorphic and hormone sensitive. Adult male and female gerbils were gonadectomized, gonadectomized and implanted subcutaneously with testosterone (T), or sham operated 4-8 weeks before sacrifice. Coronal sections through the sexually dimorphic area (SDA) of the MPOA-AH were stained for AChE. Planimeter measurements of camera lucida drawings showed that the total volume of the SDA is similar in the two sexes, but the proportion of the SDA that stains darkly and/or stands out clearly from the surround (dark volume) is larger in males. Optical density readings also indicated that AChE staining is darker in the male SDA. Gonadectomy decreases staining intensity in both sexes and reduces total SDA volume. Dark volume decreases more than 50%. Testosterone treatment reverses all effects of gonadectomy, although hormonal influences are smaller in females than in males. There were no sex differences or hormonal influences on AChE staining lateral to the SDA. The pars compacta of the male SDA was essentially devoid of AChE, indicating that this cell group is distinct from the rest of the SDA. It also shrinks after castration unless the males receive T. Histochemical changes in the SDA may be related to hormonal control of scent marking, a form of communication in this species.