Lymph node metastases from head and neck squamous cell carcinoma: MR imaging with ultrasmall superparamagnetic iron oxide particles (Sinerem MR) -- results of a phase-III multicenter clinical trial

The aim of this study was to compare the clinical usefulness of ultrasmall superparamagnetic iron oxide (USPIO) MR contrast media (Sinerem, Guerbet Laboratories, Aulnay-sous-Bois, France) with precontrast MRI in the diagnosis of metastatic lymph nodes in patients with head and neck squamous cell carcinoma, using histology as gold standard. Eighty-one previously untreated patients were enrolled in a multicenter phase-III clinical trial. All patients had a noncontrast MR, a Sinerem MR, and surgery within a period of 15 days. The MR exams were analyzed both on site and by two independent radiologists (centralized readers). Correlation between histology and imaging was done per lymph node groups, and per individual lymph nodes when the short axis was > or = 10 mm. For individual lymph nodes, Sinerem MR showed a high sensitivity (> or = 88%) and specificity (> or = 77%). For lymph node groups, the sensitivity was > or = 59% and specificity > or = 81%. False-positive results were partially due to inflammatory nodes; false-negative results from the presence of undetected micrometastases. Errors of interpretation were also related to motion and/or susceptibility artifacts and problems of zone assignment. Sinerem MR had a negative predictive value (NPV) > or = 90% and a positive predictive value (PPV) > or = 51%. The specificity and PPV of Sinerem MR were better than those of precontrast MR. Precontrast MR showed an unexpectedly high sensitivity and NPV which were not increased with Sinerem MR. The potential contribution of Sinerem MR still remains limited by technical problems regarding motion and susceptibility artifacts and spatial resolution. It is also noteworthy that logistical problems, which could reduce the practical value of Sinerem MR, will be minimized in the future since Sinerem MR alone performed as good as the combination of precontrast and Sinerem MR.

Benign paroxysmal positional vertigo of the horizontal canal

OBJECTIVES

To review the clinical features, electronystagmography findings, the possible mechanism, and a possible therapeutic approach to benign paroxysmal positional vertigo (BPPV).

METHODS

Sixty-three cases of BPPV of the horizontal canal type have been reviewed. It is characterised by horizontal nystagmus and an intense vertigo, provoked by rotation of the head in a supine patient. The horizontal nystagmus beats towards the ground on both sides, becomes more pronounced when lying on the pathological side, and then the nystagmus often changes direction.

RESULTS

Forty-eight patients underwent electronystagmography. On the pathological side, the first phase nystagmus had a mean latency of three seconds and a mean duration of 31.6 seconds. Nystagmus inversion occurred in 36 patients after a nystagmus free interval. The mean second phase nystagmus duration lasted 33.4 seconds. On the healthy side, the nystagmus had a mean latency of 3.4 seconds and a mean duration of 39.5 seconds. Fatigue was seen in six patients. Simultaneous involvement of the posterior canal was present in 16 patients. A liberatory manoeuvre was successful in six patients.

CONCLUSIONS

The liberatory manoeuvre should be tried in patients with horizontal canal vertigo. It should not be performed in patients with severe cervical arthrosis, vertebrobasilar insufficiency, or when the patient has neck pain during the manoeuvre.

Lingual thyroid imaging

Lingual thyroid is the most frequent benign mass found at the junction of the anterior two-thirds and posterior one-third of the tongue. MR has become the best non-invasive technique to make the diagnosis because it allows multiplanar imaging and provides the best soft tissue definition. Aberrant primitive vascular supply is often present and therefore angiography remains necessary because precise knowledge of the vascular supply is mandatory prior to embolisation, ligation, or operation.