Freehand two-step CT-guided brain tumor biopsy: a fast and effective interventional procedure in selected patients

Feasibility of freehand CT and 3-T MR guided brain aspiration biopsies with 18/20-gauge coaxial needles

BACKGROUND AND PURPOSE

An accurate histopathological examination with minimal neuronal damage is essential for optimizing treatment strategies of central nervous system lesions. We investigated the feasibility and safety of CT and 3-tesla (3 T) MR-guided freehand brain aspiration biopsies with 18/20-gauge coaxial needles in performing a single imaging unit.

MATERIALS AND METHODS

We reviewed CT and 3 T-MR guided freehand aspiration biopsies with 18/20-gauge coaxial needles of 33 patients (11-female and 22-male, mean and median ages: 53 years, min-max 21-79 years) in our tertiary hospital within an 8-year-period were included in this retrospective study. Lesion sizes, diagnostic yield, morbidity, and mortality rates of these biopsies without a scalp incision, surgical burr-hole, or stereotactic-instrumentation/neuro-navigation guidance were assessed. All biopsies were performed with local anesthesia and sedation within a single imaging unit of our radiology department. All free-hand biopsies were done as in-patient procedures and the patients were closely observed after the biopsies.

RESULTS

The mean diameter of the lesions was 27 mm (median 25; range 15-46 mm). The diagnostic yield of all free-hand brain biopsies was 88% [one inconclusive result (90%) for 3 T-MR; three inconclusive results (87%) for CT]. There was no major hemorrhage or hematoma, no clinical deterioration, or no infection in our patients on early- and late-phase examinations. Postprocedural minor hemorrhage with a ≤ 2 cm diameter was observed in two patients. The morbidity rate of the study population is 6%. There was no procedure-related infection or mortality in the post-procedural 3 weeks.

CONCLUSIONS

Freehand CT or 3 T-MR guided aspiration biopsy was a safe and feasible method for pathological diagnosis of intracranial lesions. Biopsy workflow was simplified with this technique. It could be considered a valuable alternative for stereotaxic biopsies, especially for centers that do not have stereotaxic equipment or experience.

The diagnostic quality of needle brain biopsy specimens obtained with different sampling methods - Experimental study

The aim is to examine whether brain tissue samples obtained through needle biopsy are better for histopathological evaluation when obtained with defined vacuum pressure, a novel needle rotation method, and using different needle type - Laitinen or Nashold. Moreover the paper aims to answer the question: Does vacuum and mechanical injury resulting from different sampling methods damage the tissue specimen challenging the diagnosis?. Eight hundred biopsy specimens from fresh swine brains were obtained using Nashold and Laitinen brain biopsy needles through inner cannula cutting or needle rotation sampling at vacuum pressure, from 0 to 0.06 MPa. The specimen weight and tissue quality for microscopic assessment were evaluated using the Mair score. Rising aspiration pressure increased the biopsy sample weight. Needle rotation delivered larger biopsy samples than the standard method. Laitinen provided larger samples than the Nashold needle, with the same sampling method or vacuum pressure. A higher histopathological diagnostic quality of tissue was obtained with the Laitinen needle than with Nashold, with higher vacuum pressure than lower pressure and finally with needle rotation than the standard method. No tissue damage caused by higher suction pressure or method of tissue separation was documented. Brain tissue samples obtained through needle biopsy are better for histopathological evaluation when obtained with higher vacuum pressure, a novel needle rotation method and with Laitinen needle. Higher suction pressure and sampling methods did not cause tissue damage.