Anatomo-functional study of the temporo-parieto-occipital region: dissection, tractographic and brain mapping evidence from a neurosurgical perspective.

The temporo-parieto-occipital (TPO) junction is a complex brain territory heavily involved in several high-level neurological functions, such as language, visuo-spatial recognition, writing, reading, symbol processing, calculation, self-processing, working memory, musical memory, and face and object recognition. Recent studies indicate that this area is covered by a thick network of white matter (WM) connections, which provide efficient and multimodal integration of information between both local and distant cortical nodes. It is important for neurosurgeons to have good knowledge of the three-dimensional subcortical organisation of this highly connected region to minimise post-operative permanent deficits. The aim of this dissection study was to highlight the subcortical functional anatomy from a topographical surgical perspective. Eight human hemispheres (four left, four right) obtained from four human cadavers were dissected according to Klingler's technique. Proceeding latero-medially, the authors describe the anatomical courses of and the relationships between the main pathways crossing the TPO. The results obtained from dissection were first integrated with diffusion tensor imaging reconstructions and subsequently with functional data obtained from three surgical cases, all resection of infiltrating glial tumours using direct electrical mapping in awake patients. The subcortical limits for performing safe lesionectomies within the TPO region are as follows: within the parietal region, the anterior horizontal part of the superior longitudinal fasciculus and, more deeply, the arcuate fasciculus; dorsally, the vertical projective thalamo-cortical fibres. For lesions located within the temporal and occipital lobes, the resection should be tailored according to the orientation of the horizontal associative pathways (the inferior fronto-occipital fascicle, inferior longitudinal fascicle and optic radiation). The relationships between the WM tracts and the ventricle system were also examined. These results indicate that a detailed anatomo-functional awareness of the WM architecture within the TPO area is mandatory when approaching intrinsic brain lesions to optimise surgical results and to minimise post-operative morbidity.

[Porocarcinoma of the parotid area. Report of a case]. / Porocarcinoma della regione parotidea. Descrizione di un caso.

The Authors describe the case of a 55 years old man, affected by ipercolesterolemy, ipertension and glaucoma, observed because of an important left parotid and laterocervical erythema with a small brown area measuring less than 1 cm inside. In the last two years the patient underwent resection of two basaliomas and of a porocarcinoma, with infiltration of margins, in the same region. Clinical and instrumental findings indicated the presence of reactive parotid's nodes; no evident lesions appeared at the examination of the ENT regions. The Authors describe and support their therapeutic approach.

Impairment of GABA release in the hippocampus at the time of the first spontaneous seizure in the pilocarpine model of temporal lobe epilepsy.

The alterations in GABA release have not yet been systematically measured along the natural course of temporal lobe epilepsy. In this work, we analyzed GABA extracellular concentrations (using in vivo microdialysis under basal and high K(+)-evoked conditions) and loss of two GABA interneuron populations (parvalbumin and somatostatin neurons) in the ventral hippocampus at different time-points after pilocarpine-induced status epilepticus in the rat, i.e. during development and progression of epilepsy. We found that (i) during the latent period between the epileptogenic insult, status epilepticus, and the first spontaneous seizure, basal GABA outflow was reduced to about one third of control values while the number of parvalbumin-positive cells was reduced by about 50% and that of somatostatin-positive cells by about 25%; nonetheless, high K(+) stimulation increased extracellular GABA in a proportionally greater manner during latency than under control conditions; (ii) at the time of the first spontaneous seizure (i.e., when the diagnosis of epilepsy is made in humans) this increased responsiveness to stimulation disappeared, i.e. there was no longer any compensation for GABA cell loss; (iii) thereafter, this dysfunction remained constant until a late phase of the disease. These data suggest that a GABAergic hyper-responsiveness can compensate for GABA cell loss and protect from occurrence of seizures during latency, whereas impaired extracellular GABA levels can favor the occurrence of spontaneous recurrent seizures and the maintenance of an epileptic state.

Technical, Anatomical, and Functional Study after Removal of a Symptomatic Cavernous Angioma Located in Deep Wernicke's Territories with Cortico-Subcortical Awake Mapping.

Introduction. The subcortical region underneath Wernicke's area (WA) is a critical crossing of the eloquent language pathways involved in all semantic, phonological, syntactic, and working memory elaboration. We report the resection of a CA located underneath the dominant WA discussing the functional and anatomical evidence provided by fMRI, dissections with Klingler's technique, and intraoperative mapping during awake surgery. Case Report. A 64-year-old right-handed female affected by daily complex focal seizures underwent f-MRI, showing language activations in the middle and inferior temporal gyri and an unusual free entry zone in the "classical" WA. The cortical intraoperative mapping partially confirmed the f-MRI results, and we approached the lesion directly through WA. Subcortical DES allowed the identification of the eloquent language pathways and the radical resection of the perilesional gliotic rim. The patient did not report deficits and she is seizures and drug free after 1-year surgery. Discussion. Cortical DES demonstrated the variability of the eloquent areas within the cortex of the dominant temporal lobe. The subcortical DES confirmed the crucial role in language elaboration and the anatomical course of the bundles underneath WA. Conclusions. Awake surgery with DES represents a reliable and dynamic technique also for safer and functional-customized resection of CAs.

Parotid localized Castleman's disease and HHV-8 infection: a case report.

Castleman's disease (CD) is an unusual massive proliferation of lymphoid tissue distinct in two clinical forms, localized and multicentric. The multicentric form has been related to human herpesvirus 8 (HHV-8), especially in HIV-infected patients, whereas the localized form of CD is still unrelated to viral pathogens. We report a case of a HIV-negative 16-year-old male referred to our hospital with a 12-month history of a painless swelling in his right parotid region. A parotidectomy was performed, and histological analysis evidenced a localized CD. The search for HHV-8 revealed an active virus infection. The patient was commenced on corticosteroid therapy and a follow-up was performed every 6 months. The patient was commenced on corticosteroid therapy and there has been no recurrence after 24 months. The authors report a case of localized parotid CD in a patient with evidence of an active HHV-8 infection. The results of this study does for the first time suggest an association between HHV-8 and localized CD in HIV-negative subjects.

Prognostic evaluation in supracricoid partial laryngectomy with cricohyoidopexy.

Identification of prognostic factors related to supracricoid partial laryngectomy may optimise indications for this surgical technique. We analysed several clinical and histopathological variables in a series of 81 patients treated with SPL at our department. Attention was focused on neoplastic spread of the anterior commissure, thyroid cartilage and prelaryngeal soft tissue of the neck. Statistical analysis (Kaplan-Meier method and Cox regression test) showed a significant decrease in survival for prelaryngeal soft tissue invasion. Due to the fact that the survival rate is not modified by the anterior commissure and thyroid cartilage infiltration, the prognostic value of prelaryngeal invasion is extremely relevant. Therefore, we suggest the oncological value of SPL even in cases of invasion of the anterior commissure or thyroid cartilage, but not beyond the outer perichondrium.

Papilloma and polyoma DNA tumor virus sequences in female genital tumors.

Human papillomaviruses (HPVs) and BKV, JCV, and SV40 polyomaviruses (PYVs) are oncogenic viruses associated with different human tumors. Our aim was to determine if PYV and HPV sequences could be detected in human genital tumors. HPV types 6b, 11, 16, and 18 and PYV were investigated in 22 genital tumor samples and the corresponding adjacent normal tissues, by PCR and filter hybridization. HPV and PYV sequences were also searched in six sperm fluid and four peripheral blood cell (PBC) samples. HPV-16 sequences were revealed in 7 of 14 cervical tumors and 1 of 1 vaginal adenocarcinoma, whereas 1 of 14 cervical carcinoma tested positive for HPV-18. Interestingly, each normal cervical tissue surrounding the neoplasm obtained from the same patient was positive for HPV type-16 and -18 with the same prevalence detected in tumors. BKV sequences were found in 9 of 14 cervical tumors, 1 of 7 vulvar tumors, and 1 of 1 adenocarcinoma, but also in normal tissues from cervix (13 of 14), vulva (6 of 7), sperm fluid (5 of 6) and PBC (3 of 4) samples. SV40 sequences were detected in 1 of 14 normal cervical tissue, 2 of 6 sperm fluids and 1 of 4 PBCs. None of the samples were JCV positive. To our knowledge, this is the first investigation reporting on the simultaneous association of both HPV and PYV with human genital tumors. These results suggest that PYV, together with HPV, may be involved as a cofactor in the onset/progression of human genital tumors, and raise the possibility that PYV act synergistically with HPV to enhance their pathogenicity in vivo. In addition, HPV and PYV may complement each other in infecting human genital tissues.

Simian virus 40 sequences and expression of the viral large T antigen oncoprotein in human pleomorphic adenomas of parotid glands.

Simian virus 40 (SV40) sequences of the early region coding for the large T antigen (Tag) oncoprotein were investigated in DNA samples from human pleomorphic adenoma (PA) of parotid glands. Specific SV40 sequences were detected, by PCR and filter hybridization with an internal oligoprobe, in 28 of 45 (62%) human PA specimens. None of the DNA samples from 11 normal salivary gland tissues was SV40-positive. DNA sequence analysis, carried out in all PCR amplified products from SV40-positive PA specimens, confirmed the SV40 specificity and indicated that PCR products had a sequence not distinguishable from SV40 DNA wild-type strain 776. SV40 Tag expression was revealed by immunohistochemistry with the specific monoclonal antibody Pab 101 in PA thin sections with a highly sensitive technical approach which retrieved the nuclear viral oncoprotein in 26 out of 28 (93%) samples previously found SV40-positive by PCR. Detection of SV40 sequences and Tag expression in human PA suggests that this oncogenic virus may play a role as a cofactor in the onset and/or progression of this benign neoplasm, or that SV40 DNA could replicate and express the Tag in PA cells.