1/8. Visual recovery after a year of craniopharyngioma-related amaurosis: report of a nine-year-old child and a review of pathophysiologic mechanisms.BACKGROUND: The probability of visual recovery in tumor-related optic neuropathy usually correlates with the severity and duration of optic pathway compromise. Recovery of visual acuity to normal levels is unexpected after profound loss of vision extending for a period of weeks and months. methods: A 9-year-old girl who had neurosurgical resection of a craniopharyngioma compressing the optic chiasm and optic tract was followed up serially with neuroimaging and clinical examinations over a 6-year period. RESULTS: Within 3 months of the diagnosis of craniopharyngioma, the girl's vision was reduced to no-light-perception blindness when she viewed with the more involved eye. The blindness correlated with an amaurotic (i.e., >3.6 log unit) relative afferent pupillary defect and an absence of any response when tested with visual field perimetry. After more than a year of total blindness and cessation of all neurosurgical and radiation therapy, visual acuity recovered to a normal level (20/25), the afferent pupillary defect improved, and sensitivity in a portion of the temporal hemivisual field was restored. In the follow-up that has extended for 5 years from the time of recovery, stability of the restored vision has been documented. CONCLUSION: Children who have tumor-related loss of vision due to damage to the anterior visual pathways may be capable of recovery after intervals of blindness that would be considered irreversible in adults. The mechanism of the recovery in our patient may have been decompression-related restoration of axoplasmic flow, followed by gradual remyelination of visual fibers, which allowed reorganization of connections to the lateral geniculate nucleus to optimize synaptic transmission.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
2/8. The diagnostic dilemma of incidentalomas. Working through uncertainty.The clinical evaluation of incidentally found nodules in the adrenal, thyroid, and pituitary glands is a challenge for physicians, regardless of their level of expertise. Choosing the most direct and cost-effective diagnostic approach and deciding when to treat or not to treat are common dilemmas in clinical practice. This article outlines one diagnostic approach using medical decision-making techniques such as heuristic thinking, critical appraisal of the literature, treatment threshold probability assessment, Bayes' theorem, and discriminant properties of diagnostic tests. These skills are usually discussed in postgraduate training curricula. Nevertheless, they often seem foreign to many clinicians. Evidence suggests that training in these techniques can improve clinical decision making. Use of the skills outlined herein provides a framework to work through the diagnostic uncertainty common in the evaluation of incidentalomas. This approach does not provide perfect answers, as noted in examplar 3 in which two experts argued about the actual pretest probability and treatment thresholds for pituitary incidentalomas. Even if there were no such disagreement, each patient presents unique issues, and there will always be some uncertainty. Nevertheless, this approach provides a starting point from which critical decisions can be made for individual patients.- - - - - - - - - - ranking = 2keywords = probability (Clic here for more details about this article) |
3/8. Corticotropin- and thyrotropin-secreting pituitary microadenomas: detection by dynamic magnetic resonance imaging.Hormone-secreting pituitary microadenomas are often not visible on magnetic resonance imaging (MRI). diagnosis requires confirmatory endocrine test results and often an invasive procedure, inferior petrosal sinus sampling (IPSS). Improved pituitary imaging may eliminate the need for IPSS in some patients, as shown in the 2 women in this report. The first patient with hirsutism, weight gain, and hypertension had intermittent elevations of urinary free cortisol, abnormal results on a low-dose dexamethasone suppression test, and positive results on a dexamethasone-suppressed ovine corticotropin-releasing hormone test (corticotropin, increase of 122%; cortisol, increase of 118%). gadolinium-enhanced MRI showed no focal lesion, but dynamic MRI (sequential images beginning immediately after contrast injection) revealed a right-sided 5-mm microadenoma, confirmed by transsphenoidal surgery. The second patient had a goiter, anxiety, increased free thyroxine and triiodothyronine levels, and a normal thyrotropin value with no response to thyrotropin-releasing hormone. magnetic resonance imaging showed no lesion, but dynamic MRI detected an 8-mm microadenoma. Although about 8% to 10% of healthy persons have incidental pituitary lesions that are 3 mm or larger on MRI, identification of a distinct lesion and positive results on a dexamethasone-suppressed ovine corticotropin-releasing hormone test should decrease the probability of a false-positive result on an imaging study. We recommend that dynamic MRI be performed in any patient with a suspected microadenoma, before IPSS is performed.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
4/8. recurrence of sellar and suprasellar tumors in children treated with hGH--relation to immunohistochemical study on GH receptor.PURPOSE: GH replacement therapy is required in the majority of children with GH deficiency after treatment of sellar and suprasellar tumors. Owing to the high cell proliferative ability of human GH (hGH), its influence on tumor recurrence has been debated. We retrospectively studied the immunohistochemical expression of the GH receptor in various tumor tissues, in order to investigate the relation between tumor recurrence and hGH replacement. methods: GH replacement therapy was performed in 25 patients (8 boys and 17 girls) after the treatment. Tumor recurrence was noted in 4 patients (craniopharyngioma: 2 patients, pilocytic astrocytoma and germinoma: 1 each). Immunohistochemical study of GH receptor in tumor tissue was carried out in those recurrent and recurrence-free cases, by using MAb 263 as a primary antibody. RESULTS: Two patients with recurrent craniopharyngioma were positive for MAb 263, but 1 recurrence-free patient was negative. patients with pilocytic astrocytoma (recurrent and recurrence-free: 1 each) were all positive. Five patients with germinoma (1 with recurrence and 4 without recurrence) were all negative. CONCLUSION: In the patients with craniopharyngioma treated with GH, a positive immunohistochemical expression of GH receptor in tumor tissue may indicate a high probability of recurrence. In our cases, GH receptor was positive in astrocytomas and negative in germinomas, with or without recurrence. It is therefore speculated that each brain tumor may have its specificity in GH receptor expression.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
5/8. acromegaly and pheochromocytoma: report of a rare coexistence.OBJECTIVE: To describe a patient with the rare coexistence of acromegaly and pheochromocytoma. methods: We report a case of a 57-year-old woman, who was initially examined because of polyarthritis, she was also diagnosed with type 2 diabetes mellitus and hypertension at age 56 years. Her history, clinical findings, laboratory results, and management are summarized, and etiologic hypotheses are discussed. RESULTS: The patient had recurrent headaches and reported an increasing size of her shoes and gloves during the previous 4 years. Enlargement of her hands and feet and a bilateral temporal field defect were noted on examination. Laboratory studies revealed high levels of insulin-like growth factor i (IGF-I) and growth hormone (GH). magnetic resonance imaging (MRI) showed a 3-cm sellar mass with impingement on the optic chiasm. The plasma level of growth hormone-releasing hormone (GHRH) was normal. She underwent transsphenoidal adenomectomy. Histologic examination confirmed a pituitary adenoma, immunoreactive for GH. Postoperatively, her headaches and arthritic pain diminished, and her levels of IGF-I and GH normalized; however, labile hypertension persisted. The urinary metanephrines and plasma catecholamines were increased. A 3-cm left adrenal mass, seen on abdominal MRI, was removed laparoscopically, after which urinary metanephrines normalized and both the diabetes and the hypertension resolved. Histopathologic analysis confirmed the diagnosis of pheochromocytoma. Immunohistochemical staining was negative for GHRH. CONCLUSION: The finding of a pheochromocytoma and acromegaly could be a fortuitous coexistence of two separate endocrine tumors; however, the probability of such an event is extremely low. A cause-and-effect relationship has been suggested because of previous reports of GHRH production by pheochromocytomas. Some investigators have also suggested that this coexistence might be a multiple endocrine neoplasia variant. Our patient had no evidence of GHRH production, nor did we document any familial autosomal dominant transmission pattern.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
6/8. Clinical features associated with lesions other than pituitary adenoma in patients with an optic chiasmal syndrome.PURPOSE: Pituitary adenomas are the most common cause of an optic chiasmal syndrome, and treatment of these lesions is considerably different from the treatment of most of the other lesions in this region. Although the diagnosis of a pituitary adenoma is usually inferred from the results of neuroimaging, lesions other than pituitary adenomas can have an appearance that suggests an adenoma. The objective of our study was to determine whether there are clinical findings that suggest a lesion producing a chiasmal syndrome is something other than a pituitary adenoma. DESIGN: Retrospective, case-controlled, analysis of medical record data. methods: The records of the Neuro-ophthalmology Unit of the Wilmer eye Institute were searched for patients with a chiasmal syndrome who had been evaluated before treatment and for whom pathologic or laboratory confirmation of the etiology was available. Presenting clinical features of these patients were recorded, and analyses with both a single variable and multiple variables were performed to determine whether there were any features that could identify with a high degree of probability the etiology of the lesion producing the syndrome. RESULTS: The search revealed 149 patients who met the inclusion criteria, including 90 patients with pituitary adenomas and 59 patients with other lesions. Variables that were highly suggestive of an etiology other than pituitary adenoma included symptomatic visual loss, younger age, unilateral optic disk pallor, a relative afferent pupillary defect, and an absolute or a complete visual field defect or one was greater inferiorly than superiorly. CONCLUSION: Although no single clinical feature can be used to determine the specific nature of a lesion that produces an optic chiasmal syndrome, certain features are highly suggestive of an etiology other than pituitary adenoma. When these features are present, the likelihood that a suprasellar lesion is a pituitary adenoma is much lower, regardless of the appearance on neuroimaging.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
7/8. cerebrospinal fluid rhinorrhea: a complication of therapy for invasive prolactinomas.The majority of invasive prolactinomas can be predicted with a high probability if the preoperative prolactin level is above 2000 ng/ml. As these tumors cannot be extirpated radically, adjunctive radiation therapy is used to improve the results of treatment. On the basis of reports that bromocriptine induces tumor shrinkage and has an antimitotic effect, we combined adjunctive irradiation with bromocriptine therapy in 14 patients who had particularly extensive invasion. Two of these patients developed cerebrospinal fluid rhinorrhea 3 and 5 months, respectively, after the completion of radiation therapy. In both patients, the fistula was localized in the sellar region and was closed successfully. Rapid tumor shrinkage caused by irradiation combined with bromocriptine therapy may be a factor causing this complication; postoperative rhinorrhea is otherwise extremely rare in our surgical series. We also observed a third patient who did not have an operation, but who developed rhinorrhea after a course of irradiation and bromocriptine treatment. The periods of rhinorrhea coincided with periods of bromocriptine treatment.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |
8/8. Symptomatic Chiari-I malformation in a patient with acromegaly.We describe, for the first time, a patient with both symptomatic acromegaly and Chiari-I malformation. These conditions could coexist by chance alone, but the probability of both presenting simultaneously in a previously healthy man seem quite remote. Alternatively, acromegaly through associated bony and soft tissue enlargement could lead to the development of symptoms from Chiari-I malformation in this patient.- - - - - - - - - - ranking = 1keywords = probability (Clic here for more details about this article) |